Get 20M+ Full-Text Papers For Less Than $1.50/day. Subscribe now for You or Your Team.

Learn More →

Evidence forChlamydia trachomatisas a Human Papillomavirus Cofactor in the Etiology of Invasive Cervical Cancer in Brazil and the Philippines

Evidence forChlamydia trachomatisas a Human Papillomavirus Cofactor in the Etiology of Invasive... Downloaded from https://academic.oup.com/jid/article/185/3/324/895185 by DeepDyve user on 15 July 2021 Evidence for Chlamydia trachomatis as a Human Papillomavirus Cofactor in the Etiology of Invasive Cervical Cancer in Brazil and the Philippines 1 1 1,2 Jennifer S. Smith, Nubia Mun ˜ oz, Rolando Herrero, International Agency for Research on Cancer, Lyon, France; 3 4 1 ´ ´ Proyecto Epidemiologico Guanacaste, San Jose,Costa Rica; Jose Eluf-Neto, Corazon Ngelangel, Silvia Franceschi, 3 4 ˜ ˜ 5 6,a Universidade de Sao Paulo, Sao Paulo, Brazil; Philippine General F. Xavier Bosch, JanM.M.Walboomers, Hospital, University of the Philippines, Manila; Institu Catala and Rosanna W. Peeling 6 d’Oncologia, Barcelona, Spain; Free University Hospital, Amsterdam, The Netherlands; National Laboratory for Sexually Transmitted Diseases, Health Canada, Winnipeg, Canada Chlamydia trachomatis infection was examined as a cause of invasive cervical cancer (ICC) among women with human papillomavirus (HPV) infection. In total, 499 women with incident ICC (ICC patients) and 539 control patients from Sa ˜ o Paulo, Brazil, and Manila, the Philippines, were included. C. trachomatis antibodies were detected by microimmunofluorescence assay. Presence of HPV DNA in cervical specimens was determined by a polymerase chain reaction– based assay. C. trachomatis seropositivity was associated with sexual behavior but not with HPV infection. C. trachomatis increased the risk of squamous cervical cancer among HPV-positive women (odds ratio, 2.1; 95% confidence interval, 1.1 – 4.0). Results were similar in both countries. There was a suggestion of increasing squamous cancer risk with increasing C. trachomatis anti- body titers. This large study examined C. trachomatis and cervical cancer, taking into account the central role of HPV infection. C. trachomatis infection was found to be a possible cofactor of HPV in the etiology of squamous cervical cancer, and its effect may be mediated by chronic inflammation. Extensive data show that human papillomavirus (HPV) is the atypia [2] and cervical neoplasia [3]. Genital C. trachomatis in- central cause of cervical cancer, and high-risk HPV types are as- fections may result in chronic cervicitis, pelvic inflammatory dis- sociated with a greater disease risk [1]. Only a small proportion ease, and endometritis, whereas ocular C. trachomatis infections of women infected with HPV infection progress to invasive cer- may cause trachoma and may result in blindness in some cases. vical cancer (ICC). Thus, the development of ICC depends on Interest in genital C. trachomatis infection as a potential etio- other cofactors acting in conjunction with HPV, such as other logic factor for ICC has been related to its asymptomatic nature, sexually transmitted infections (STIs), smoking, hormones, nu- persistence if left untreated, and induction of metaplasia [4] and tritional deficiencies, or host- genetic/immunologic responses. chronic inflammation [5]. Clinical observations in the 1970s indicated that genital infec- Two epidemiologic studies examined C. trachomatis in the tion with Chlamydia trachomatis was associated with cervical etiology of ICC and in the context of HPV by using sensitive poly- merase chain reaction (PCR)– based assays for HPV DNA detec- tion [6, 7]. In a study of cervical neoplasia [6], C. trachomatis Received 10 August 2001; revised 9 October 2001; electronically published seropositivity was a significant risk factor for carcinoma in situ 17 January 2002. Presented in part: 18th International Papillomavirus Conference, Bar- in Spain and Colombia after adjusting for HPV DNA. How- celona, 23– 28 July 2000 (abstract 71). ever, when combined country analyses were restricted to HPV Informed consent was obtained from all study participants. The study DNA– positive case and control patients, C. trachomatis anti- was approved by the International Agency for Research on Cancer ethics committee and by local ethics committees in Brazil and the Philippines. bodies were not significantly associated with either in situ carci- Financial support: Conselho Nacional de Desenvolvimento Cientifico e noma or ICC. Some misclassification of HPV DNA resulting Tecnologico– Brazil (JEN-204453/88.7) and Fundac ¸a ˜odeAmparo a from the use of a first-generation PCR– based assay could not Pesquisa do Estado de Sa ˜o Paulo (90/2319-9); Rockefeller Foundation (PS 9824); European Community (CI 1-0371-F[CD]), Preventiefonds be ruled out. Another study reported no association between C. (28-1502.1); The Netherlands; World Health Organization, Division of trachomatis antibodies and cervical neoplasia after adjusting for Human Reproduction (98101). HPV DNA among women in Honduras [7]. Results restricted to Deceased. Reprints or correspondence: Dr. J. S. Smith, International Agency for HPV DNA– positive participants were not presented, although Research on Cancer, 150 Cours Albert Thomas, F-69372 Lyon Ce ´dex 08, an ELISA known to have C. trachomatis/C. pneumoniae cross- France (smith@iarc.fr). reactivity was used. To further examine the role of C. trachomatis The Journal of Infectious Diseases 2002;185:324–31 infection as a cofactor of HPV in the etiology of ICC, we present q 2002 by the Infectious Diseases Society of America. All rights reserved. results from 2 International Agency for Research on Cancer 0022-1899/2002/18503-0007$02.00 Downloaded from https://academic.oup.com/jid/article/185/3/324/895185 by DeepDyve user on 15 July 2021 JID 2002;185 (1 February) C. trachomatis, HPV, and ICC 325 at270 C without additives. Histologic slides for cancer diagnosis (IARC) ICC case-control studies conducted in Sa ˜o Paulo, Brazil, were reviewed by an expert pathologist. The stage of disease was and Manila, the Philippines. coded according to International Federation of Gynecology and Obstetrics standards. Cervical exfoliated cells were collected, by sampling the ectocervix with 2 wooden spatulas and the endocervix Methods with 2 cytobrushes, and were placed in tubes with PBS, centrifuged, This analysis is based on 2 cervical cancer case-control studies of and stored at270 C until shipment to a central laboratory for HPV 499 women with incident ICC (ICC patients) and 539 control pa- DNA testing. tients in Sa ˜o Paulo and Manila, selected as described elsewhere Laboratory procedures. Serum IgG antibody responses to C. [8, 9]. Both studies were part of an IARC multicenter case-control trachomatis were determined by a microimmunofluorescence (MIF) study and used similar protocols and questionnaires for recruitment assay, which, at present, is considered to be the most accurate sero- and data collection. logic method [10]. The antigen panel consists of purified elementary All women with ICC were newly diagnosed and had received bodies of C. trachomatis (serovar A and 3 pooled serovar groups of no previous treatment, and their ICC was histologically confirmed. BDE, CJHI, and FGK) and C. pneumoniae [11]. C. pneumoniae was Hospital-based control patients were selected and were frequency included in the antigen panel to monitor cross-reactive antibody re- age-matched to the case patients by quinquennium of age. Women sponses and to test for specificity of the C. trachomatis findings. were not eligible to participate as control patients if they had received Clinically, C. trachomatis serovars D– K are primarily associated any previous cervical cancer treatment or if they had diseases pos- with genital chlamydial infections, whereas serovars A– C are as- sibly sharing risk factors with cervical cancer (e.g., cardiovascular sociated with both hyperendemic trachoma and genital infection. or cerebrovascular disease, chronic bronchitis, emphysema, or neo- Serologic testing was done without knowledge of case-control status. plasia of the breast, reproductive or respiratory organs, anus, oral All serum samples were screened for C. trachomatis at 1 : 8 cavity, esophagus, bladder, or liver). dilution and were titered to end point. With the exceptions mentioned In Brazil, 199 ICC patients (96.6% of eligible subjects) were re- below, an IgG titer>1:8against anyof the C. trachomatis serovar cruited from 5 public hospitals and 2 cancer hospitals in Sa ˜oPaulo groups was considered to be evidence of past infection with C. tra- between June 1990 and June 1991. As hospital-based controls, 225 chomatis. An IgG titer>1 : 16 against C. pneumoniae was considered women (94.5% of those eligible) were interviewed and were selected to be evidence of past C. pneumoniae infection. Serum samples that from the 5 public hospitals. In total, 150 women with ICC (75.4% had identical titers for all C. trachomatis and C. pneumoniae species of participants; 137 with squamous and 13 with adenocarcinoma/ were also tested with C. psittaci (avian strain 6BC) to determine the adenosquamous cancer) and 173 control patients (76.9%) with chla- presence of broad Chlamydia species cross-reactivity. Serum sam- mydia serology and HPV DNA results were included in this analysis. ples with identical titers for all chlamydial species (C. trachomatis, The main diagnostic categories of Brazilian control patients were C. pneumoniae, and C. psittaci) were considered to be cross-reactive diseases of the circulatory system (21.8%), infectious and parasitic and were excluded from analyses: 7 Brazilian women (5 ICC patients diseases (12.9%), diseases of the digestive tract (12.3%), neoplasms and 2 control patients) and 4 Philippine women (2 ICC patients and 2 (9.5%), and diseases of the nervous system (8.9%). control patients) in this category were excluded. Serum samples from In the Philippines, 387 ICC patients (100% of those eligible) and 9 ICC patients and 9 control patients who were seropositive for sero- 387 control patients (98.7% of those eligible) were identified among var A and negative for all other C. trachomatis serovars were con- patients at the Philippine General Hospital in Manila between April sideredtohaveevidenceofpast C. trachomatis ocular trachoma 1991 and April 1993. A total of 349 women with ICC (90.2% of infections and were excluded from analyses. participants: 318 with squamous and 31 with adenocarcinoma/ A blinded reproducibility study was conducted by retesting a ran- adenosquamous cancer) and 366 (94.6%) control patients with chla- dom sample of 10% of the serum specimens (n ¼ 105) twice by MIF. mydia serology and HPV DNA results were included in this analy- C. trachomatis serovars A, BDE, CJHI, and FGK and C. pneumoniae sis. The main diagnostic categories of control patients from the Phi- had the following percentages of agreement: 83.9%, 87.5%, 84.8%, lippines were urinary tract infections (19.5%), benign disorders of 83.9%, and 87.5%, respectively. The k agreement for C. trachomatis the genital tract (14.3%), menstrual disorders (11.1%), and diseases positivity for the 2 repeat tests was 0.75 overall: 0.65 for case patients of the circulatory system (7.9%). Fifty-five healthy women (14.9%) and0.80for control patients. The k agreement for C. pneumoniae accompanying outpatients, with similar sociodemographic and be- positivity was 0.6 for the 2 repeat tests overall: 0.56 for case and havioral characteristics as the hospital-based control patients, 0.65 for control patients. were included as control subjects. Screening for HPV DNA was done by a PCR assay based on GP5/ Specially trained interviewers administered a standardized ques- + + 6/TS-PCR and G5 /6 primers, as described elsewhere [8, 9]. In brief, tionnaire on sociodemographic characteristics, sexual behavior, and amplification of a fragment of the b-globin gene served as an internal reproductive and contraceptive history. Participating women were control for sufficiency of each specimen for amplification. Speci- asked to provide 10 mL of blood for serologic testing of C. trachoma- mens were labeled “HPV X” for HPV-positive specimens when a tis and herpes simplex virus (HSV)-2. Blood specimens were pro- specific HPV type could not be determined. GP5/6/TS-PCR primers cessed by centrifugation at the site of collection. The separated detect sequenced HPV types 6, 11, 16, 18, 31, and 33, and unse- serum samples were placed in tubes, frozen at220 C, and shipped + + quenced HPV types at subpicogram levels. G5 /6 primers detect to Lyon, France, for storage. For HPV DNA detection, cervical exfo- liated cells from all subjects and cervical biopsy specimens from over 30 different HPV types including types 6, 11, 16, 18, 26, 31, patients were obtained. Cervical biopsy specimens were kept frozen 33– 35, 39, 40, 42– 45, 51, 52, 54, 56– 59, 61, 66, 68, 70, 72, 73, Downloaded from https://academic.oup.com/jid/article/185/3/324/895185 by DeepDyve user on 15 July 2021 326 Smith et al. JID 2002;185 (1 February) IS39, MM4, MM7, CP 6108, CP 8304, and W13b [9]. All case and Results control patient specimens labeled as HPV X were retested with + + G5 /6 primers. HPV types considered as high risk included HPV In total, we studied 455 ICC patients with squamous ICC, 16, 18, 26, 31, 33, 35, 39, 45, 51 – 53, 56, 58, 59, 66, 68, 73, IS39, 44 with adenocarcinoma/adenosquamous ICC, and 539 age- and W13b. To further investigate HPV positivity among subjects, matched control patients from Brazil and the Philippines (table we retested all HPV-negative biopsy specimens and a sample of 1). C. trachomatis seroprevalence was significantly higher among + + negative cell pellets from control patients with GP5 /6 or E7 HPV all squamous ICC patients (47.7%) than among control patients + + PCR primers [12]. With these additional G5 /6 andE7results, (22.1%; P< .0001) but was not significantly higher among adeno- HPV DNA prevalence among squamous ICC patients increased in carcinoma/adenosquamous ICC patients (29.6%) than among both Brazil (from 88.7% to 92.7%) and in the Philippines (from control patients (22.1%; P ¼ :3). The difference in seropreva- 93.8% to 95.3%). We took special precautions to minimize contami- lence between squamous ICC patients and control patients nation, as described elsewhere in detail [12]. To control for any increased with increasing C. trachomatis antibody titer. Among potential effect of HSV-2, HSV-2 antibodies were detected by use control patients, C. trachomatis seroprevalence was similar in of the Gull HSV-2 gG ELISA with Western blot confirmation of all Brazil (20.2%) and the Philippines (23.0%). C. pneumoniae sero- positive, equivocal, and borderline negative ELISA results, as de- scribed elsewhere [13]. positivity did not significantly differ between ICC patients and Because this case-control study was designed to investigate C. control patients but was lower among control participants in trachomatis as an HPV cofactor, only participants having both Brazil (68.2%) than in the Philippines (82.8%; P , :001). HPV valid C. trachomatis serology and HPV DNA results could be in- DNA positivity was significantly higher among all ICC patients cluded in this analysis. The main reason for exclusion was unavail- (93.8%) than among control patients (11.3%; P , :001). ability of HPV results due to b-globin negativity. Participating and The prevalence of C. trachomatis antibodies did not differ sig- nonparticipating women had similar sociodemographic and sexual nificantly by clinical cancer stage in either Brazil or the Philip- behavior characteristics (data not shown). pines (data not shown) or for ICC patients from the 2 countries Statistical analyses. Odds ratios (ORs) and 95% confidence in- combined (combined countries): stage I, 40.2% (n ¼ 87); stage tervals (CIs) were estimated by multiple logistic regression [14]. ORs II, 47.8% (n ¼ 180); stage III, 47.5% (n ¼ 200); and stage IV, for the association were adjusted for 4 age groups (,40, 40 – 49, 50.0% (n ¼ 4; P trend = .3). 50– 59, and>60 years), country of residence, and other confounding Table 2 shows that C. trachomatis seropositivity was signifi- factors as stated. Missing values were excluded from statistical analy- cantly associated with sexual behavioral factors among control ses. Trend tests for categorized data were conducted by assigning sequential scores to the ordered categories. patients in the age-adjusted analyses. In the multivariate model, Table 1. Seroprevalence of Chlamydia antibodies and presence of human papillomavirus (HPV) DNA among invasive cervical cancer patients and control patients, by country and overall. Brazil The Philippines Overall SQ AD All control SQ AD All control SQ AD Control Variable patients patients patients patients patients patients patients patients patients No. of women with results 137 13 173 318 31 366 455 44 539 Mean age, years 52.9 47.8 52.5 47.2 48.5 46.5 48.9 48.3 48.4 C. trachomatis seropositive 38.0 30.8 20.2 51.9 29.0 23.0 47.7 29.6 22.1 Titer 8 16.1 15.4 13.3 11.0 9.7 9.0 12.5 11.4 10.4 32 12.4 15.4 4.1 25.8 9.7 10.9 21.8 11.4 8.7 128 9.5 0.0 2.9 15.1 9.7 3.0 13.4 6.8 3.0 C. trachomatis serovar A 34.3 30.8 17.9 46.9 25.8 20.2 43.1 27.3 19.5 BED 36.5 30.8 20.2 51.3 29.0 22.7 46.8 30.0 21.9 CHIJ 30.7 30.8 14.5 46.2 19.4 19.4 41.5 22.7 17.8 FGK 26.3 23.1 13.9 44.7 22.6 17.8 39.1 22.7 16.5 C. pneumoniae seropositive 74.5 76.9 68.2 76.7 90.3 82.8 76.0 86.4 78.1 HPV DNA Positive 92.7 76.9 16.2 95.3 90.3 9.0 94.5 86.4 11.3 High risk 91.3 100.0 60.7 93.4 92.9 63.6 92.8 94.7 62.3 NOTE. AD, adenocarcinoma/adenosquamous carcinoma; SQ, squamous carcinoma. Serovar positivity not mutually exclusive. Percentage of high-risk HPV types among HPV-positive participants. Downloaded from https://academic.oup.com/jid/article/185/3/324/895185 by DeepDyve user on 15 July 2021 Table 2. Prevalence of Chlamydia trachomatis and C. pneumoniae seropositivity by selected risk factors and associated odds ratios (ORs) among control women from Brazil and the Philippines. No. of C. trachomatis No. of C. pneumoniae a b a b Risk factor women seropositive OR (95% CI) OR (95% CI) women seropositive OR (95% CI) OR Age, years ,40 123 30.1 1 1 123 71.5 1 1 40 – 49 155 19.4 0.6 (0.3–1.0) 0.4 (0.2–0.8) 155 80.0 1.9 (1.0–3.3) 1.8 (1.0–3.3) 50 –59 158 18.4 0.5 (0.3–0.9) 0.5 (0.3–0.9) 158 83.5 2.3 (1.3–4.1) 2.2 (1.2–4.2) >60 103 22.3 0.7 (0.4–1.3) 0.7 (0.3–1.4) 103 74.8 1.6 (0.9–3.0) 1.5 (0.8–3.0) P trend = .2 P trend = .3 P trend = .1 P trend = .2 Country Brazil 173 20.2 1 1 173 68.2 1 1 The Philippines 366 23.0 1.1 (0.7–1.8) 2.2 (1.2–3.9) 366 82.8 2.4 (1.6–3.7) 2.2 (1.4–3.6) Age at first sexual intercourse, years >21 286 18.2 1 1 286 78.0 1 1 17–20 190 24.2 1.4 (0.9–2.2) 1.1 (0.7–1.8) 190 78.4 1.1 (0.7–1.8) 1.2 (0.7–2.0) ,17 63 33.3 2.5 (1.3–4.6) 1.7 (0.8–3.5) 63 77.8 1.2 (0.6–2.4) 1.4 (0.7–3.1) P trend = .02 P trend = .4 P trend = .5 P trend = .4 Total lifetime sex partners 1 447 19.7 1 1 447 79.9 1 1 >2 92 33.7 2.4 (1.4–4.1) 1.6 (0.9–2.9) 92 69.6 0.7 (0.4–1.3) 0.7 (0.4–1.2) Woman reported husband had other sex partners Never 356 14.6 1 1 356 77.3 1 1 Ever/uncertain 183 36.6 3.6 (2.3–5.5) 3.2 (2.1–5.1) 183 79.8 1.3 (0.8–2.0) 1.4 (0.9–2.3) Parity 0 –1 62 21.0 1 1 62 77.4 1 1 2– 4 249 20.9 1.1 (0.5–2.2) 1.2 (0.6–2.5) 249 76.3 0.9 (0.4–1.7) 0.8 (0.4–1.6) >5 228 23.7 1.6 (0.8–3.2) 1.4 (0.6–3.0) 228 80.3 1.0 (0.5–2.0) 0.9 (0.4–1.8) P trend = .3 P trend = .4 P trend = .7 P trend = .7 Herpes simplex virus Seronegative 433 18.7 1 1 433 79.9 1 1 Seropositive 106 35.9 3.3 (1.9–5.6) 2.1 (1.1–3.8) 106 70.8 0.9 (0.5–1.4) 0.8 (0.5–1.5) NOTE. CI, confidence interval. Adjusted by age and country of residence. Adjusted by age, country of residence, and all other factors in the table. Downloaded from https://academic.oup.com/jid/article/185/3/324/895185 by DeepDyve user on 15 July 2021 328 Smith et al. JID 2002;185 (1 February) Table 3. Odds ratios (ORs) of human papillomavirus (HPV) DNA ticipants, C. trachomatis– seropositive women had a 2-fold in- positivity among control women by Chlamydia trachomatis and C. creased risk of squamous ICC (OR, 2.1; 95% CI, 1.1– 4.0). Re- pneumoniae seropositivity in Brazil and the Philippines combined. sults were similar in both countries. Elevated C. trachomatis HPV-positive/ antibody titers were associated with an increased risk of squa- HPV-negative mous cervical cancer, with a significant trend (P trend = .01). Parameter control women OR (95% CI) Further analyses controlling for age at first intercourse, number C. trachomatis IgG seronegative 45/375 1 of sex partners, parity, cytologic screening, smoking, or oral C. trachomatis IgG seropositive 16/103 1.4 (0.7–2.7) contraceptive use did not significantly affect risk estimates Seropositive titer + + (data not shown). After excluding the additional GP5 6 or 8 7/49 1.2 (0.5–2.9) 32 8/39 1.6 (0.7–3.7) E7 HPV PCR results for all HPV-negative biopsy specimens 128 1/15 P for trend = .2 and a sample of negative cell pellets from control patients, re- C. pneumoniae calculated ORs for association between C. trachomatis and ICC Seronegative 15/103 1 were not significantly different from those presented in table 4 Seropositive 46/375 1.0 (0.5–2.0) (data not shown). The presence of C. trachomatis antibodies NOTE. CI, confidence interval. was associated with an increased (2-fold) risk for squamous OR adjusted for age, country of residence, herpes simplex virus (HSV)–2 seropositivity, and husband’s no. of sex partners during marital relationship. cancer among women with high-risk HPV DNA in the com- OR adjusted for age, country of residence, HSV-2 seropositivity, hus- bined country analysis (OR, 2.4; 95% CI, 1.1– 5.4; data not band’s no. of sex partners during marital relationship, and C. trachomatis shown). The effect of C. trachomatis among HPV-negative par- seropositivity. ticipants (OR, 3.4; 95% CI, 1.4– 8.3), based on 25 HPV-nega- tive women, was consistent with that among HPV-positive participants (data not shown). C. trachomatis was positively associated with a woman’s report C. pneumoniae infection was not associated with squamous or of her husband’s sexual behavior and HSV-2 seropositivity. adenosquamous ICC in either Brazil or the Philippines (data not Women,40 years old had higher C. trachomatis seropositivity shown) or in the combined analysis of both countries. The associ- than older control patients. After controlling for sexual behavior, Filipino control participants were more likely than Brazilian control participants to be C. trachomatis seropositive. Elevated C. trachomatis antibody titers (.128) among control patients Table 4. Odds ratios (ORs) of invasive squamous cervical cancer were clearly associated with sexual behavioral factors (data not among human papillomavirus (HPV) DNA–positive study partici- shown). C. trachomatis seropositivity did not significantly differ pants, by Chlamydia trachomatis and C. pneumoniae seropositivity. by any specific diagnostic category among control participants HPV-positive patients/ (data not shown). C. pneumoniae seropositivity was not associ- HPV-positive Parameter control women OR (95% CI) ated with sexual behavior among control patients. To determine whether past C. trachomatis infection may in- C. trachomatis IgG crease the risk of being a carrier of HPV infection, we examined Brazil Seronegative 78/22 1 associations between C. trachomatis antibodies and HPV DNA Seropositive 49/6 2.5 (0.9–6.9) among control patients (table 3). Results were similar in Brazil The Philippines and the Philippines (data not shown). Neither C. trachomatis a Seronegative 147/23 1 seropositivity (OR, 1.4; 95% CI, 0.7– 2.7) nor high C. trachoma- Seropositive 156/10 1.6 (0.7–3.7) Both countries combined tis antibody titers (OR, 1.6; 95% CI, 0.7– 3.7) were significantly Seronegative 225/45 1 associated with HPV DNA detection. C. pneumoniae seroposi- Seropositive 205/16 2.1 (1.1–4.0) tivity was not associated with HPV DNA positivity among con- Seropositive titer trol patients. 8 56/7 1.4 (0.6–3.3) In relation to cervical cancer, C. trachomatis seropositivity 32 94/8 2.7 (1.2–5.9) 128 55/1 P for trend = .01 was significantly associated with squamous ICC after adjusting C. pneumoniae, both for age, HPV DNA positivity, HSV-2 seropositivity, the report- countries combined ed sexual behavior of a woman’s husband (for the combined c Seronegative 102/15 1 countries, OR, 2.5; 95% CI, 1.5– 4.1), and elevated (.32) C. Seropositive 328/46 1.2 (0.6–2.3) trachomatis antibody titers (OR, 3.9; 95% CI, 2.1– 7.3; data not NOTE. CI, confidence interval. shown). OR adjusted for age, herpes simplex virus (HSV)–2 seropositivity, and husband’s no. of sex partners during marital relationship. To more effectively control for the strong effect of HPV, analy- Combined country analyses were adjusted for country of residence. ses were restricted to squamous ICC patients and control patients OR adjusted for age, HSV-2 seropositivity, husband’s sex partners during with HPV DNA (table 4). Among all HPV DNA– positive par- marital relationship, and C. trachomatis seropositivity. Downloaded from https://academic.oup.com/jid/article/185/3/324/895185 by DeepDyve user on 15 July 2021 JID 2002;185 (1 February) C. trachomatis, HPV, and ICC 329 ations between C. trachomatis and squamous cervical cancer Our data did not show a significant association between were similar for C. pneumoniae– seropositive and – seronegative C. trachomatis seropositivity and HPV DNA positivity, which women (data not shown). may be due to the different nature of these 2 markers. Whereas On the basis of data from 44 ICC patients, C. trachomatis sero- HPV DNA indicates both current or persistent HPV infection, positivity was not associated with adenocarcinoma/adenosqua- C. trachomatis seropositivity represents a more cumulative mea- mous ICC risk in Brazil or the Philippines (data not shown) or in sure of exposure to C. trachomatis infection. the combined country analysis (OR, 0.8; 95% CI, 0.3– 2.2) The use of species-specific MIF serologic testing allows the among HPV DNA– positive participants after controlling for ascertainment of past C. trachomatis infection while differentiat- age, HSV-2 seropositivity, and a woman’s reported history of ing C. pneumoniae antibodies from C. trachomatis serovar group- her husband’s sexual behavior. ings [11]. Unlike C. pneumoniae, C. trachomatis antibodies were Analyses were conducted for each C. trachomatis serovar significantly associated with sexual behavior and with squamous group (A, BED, CHIJ, and FGK). The association between C. ICC. Results from our blinded reproducibility test showed a high trachomatis and squamous or adenocarcinoma/adenosquamous agreement between seropositivity to the different C. trachomatis ICC was similar in all serovar groups (data not shown). serovars (.83%) and “substantial” k agreement for C. trachoma- tis positivity [24] for both case and control participants. C. tracho- matis IgG antibodies may persist for years among women with Discussion acute infections [25], and antibody persistence and elevated titers We believe that our study is the largest of C. trachomatis, HPV, are considered to be related to longer, more severe, and recurrent and ICC to date that takes into account the strong effect of HPV chlamydial infections [26]. Reliable data on the natural history and type-specific C. trachomatis serology results. These data and long-term persistence of C. trachomatis antibodies are, how- indicate a moderate, but significant, association between C. ever, lacking, although the disappearance of IgG C. trachomatis trachomatis infection and ICC in the presence of HPV DNA. serum antibodies is considered to be rare in women [10, 27]. C. trachomatis seropositivity was consistently associated with Among the potential limitations of our study is the use of hos- an increased risk (2-fold)ofsquamousICC amongHPV pital-based control patients. This could have led to biased results DNA– positive participants, after adjusting for confounding if C. trachomatis seroprevalence among the control patients was factors. A pattern of increasing squamous ICC risk with increas- not representative of the population source for the ICC patients. ing C. trachomatis titers was observed, which suggests a dose- Control participants in these studies, however, had a wide range response effect. C. trachomatis was not clearly associated with of diagnostic categories and were recruited in tertiary public hos- adenocarcinoma/adenosquamous carcinoma, although this ob- pitals with wide reference populations. C. trachomatis seroposi- servation was based on a small number of cases. tivity did not differ significantly by any major diagnostic category The positive associations of squamous ICC and C. trachomatis among control patients. Although the case-control design did infection in this study (OR, 2.1) are consistent with results from not elucidate the temporal association between C. trachomatis case-control studies of ICC that have used less sensitive methods seropositivity and ICC, all ICC patients in our study were newly than PCR for HPV detection, namely, Southern blotting (OR, 4.8) diagnosed and had not received previous cervical cancer treat- ment and the frequency of C. trachomatis seropositivity did not [15] and HPV serology (OR, 1.7– 2.2) [16, 17]. Nested case- vary by the clinical stage of ICC, thus reducing the likelihood control studies have primarily found significant positive associ- ations between C. trachomatis serum antibodies and ICC (OR, that our findings may be attributed to the development of C. 1.5– 2.5) [18– 20], although one smaller study found a nonsignifi- trachomatis antibodies following the onset of invasive disease. cant 3-fold increase in ICC risk (OR, 3.0; 95% CI, 0.7– 13.4) The power of our analyses examining C. trachomatis as an [21]. However, residual confounding due to HPV in these studies HPV cofactor in the etiology of cervical cancer is also limited cannot be excluded, because less sensitive HPV serologic assays because of the small number of HPV-positive control patients. were used to assess HPV status [22]. Persistent HPV DNA infections have been associated with an Due to the notable association between HPV and ICC, a prereq- increased risk of cervical neoplasia, particularly among women uisite to evaluating an HPV cofactor is to accurately assess HPV with high-risk HPV types [28]. In this study, a cross-sectional infection. The PCR-based assay used is one of the most accurate measurement of HPV DNA was taken among case and control methods to assess cervical HPV infection [23]. Given the notably patients. The extent to which this HPV DNA measurement among high prevalence of HPV DNA in cervical cancer worldwide control patients .45 years old represents a persistent HPV in- (99%) [12], we concentrated on analyses restricted to HPV fection merits further investigation. However, C. trachomatis DNA– positive women to reduce the likelihood of residual HPV antibodies were associated with an increased squamous cancer confounding, so as to assess C. trachomatis as an HPV cofactor. risk when analyses were restricted to women who had more However, an association between C. trachomatis antibodies and persistent, high-risk DNA types. squamous ICC also emerged among HPV DNA– negative case The increasing risk of squamous cervical cancer with in- and control patients. creasing C. trachomatis antibody titers gives further support to Downloaded from https://academic.oup.com/jid/article/185/3/324/895185 by DeepDyve user on 15 July 2021 330 Smith et al. JID 2002;185 (1 February) the results found. High antibody titers may be a marker of per- parasitic infections causing chronic inflammation have also sistent C. trachomatis infection, since women with long-term been implicated in human cancer, such as Helicobacter pylori complications of chlamydial infection, such as pelvic inflam- with stomach cancer and Schistosoma haematobium with blad- matory disease or tubal infertility, have significantly higher der cancer. levels of MIF antibody than women with cervical chlamydial Our results, based on a large number of newly diagnosed ICC infection [29]. patients, consistently indicate a potential etiologic role for C. No specific C. trachomatis serovar group (A, BDE, CJHI, or trachomatis infection as an HPV cofactor in the development of FGK) was associated with a higher squamous cell cancer risk. squamous ICC. Further epidemiologic studies are needed to clar- The microbial risk factor associated with squamous cancer risk ify the role of C. trachomatis in the etiology of cervical cancer. may not be serovar specific. Alternatively, the statistical power Additional prospective data are needed on the induction of inflam- to detect meaningful differences between the associations of mation by C. trachomatis andother STIs andonthe effect of different C. trachomatis serovar groups and ICC by use of sero- their relative timing, in conjunction with HPV infection, on the logic testing may be limited because of common subspecies risk of cervical neoplasia, in addition to the effect of the treat- cross-reactivity and because women may have been infected ment of C. trachomatis infection on the progression of cervical with multiple serovars. The main shortcoming of this study is neoplasia. that, by use of BDE, CJHI, and FGK serovar group data in the MIF assay, it was not possible to distinguish clearly between Acknowledgments exposure to C. trachomatis genital infections and hyperendemic ocular trachoma infections. Notwithstanding, it is difficult to be- We are indebted to the study participants and the gynecologists, lieve that our results can be attributed to an effect of trachoma in- pathologists, and oncologists who facilitated the identification of fection, because both studies were conducted in urban centers specimens and to the field work supervisors. We thank Keerti V. Shah for critical review of this manuscript, Liz Dillon for sero- without a history of hyperendemic trachoma, and high C. tracho- logic testing of chlamydial antibodies by MIF, Chris Meijer and matis antibody titers were significantly associated with sexual Adriaan van den Brule for assisting with HPV DNA testing, behavior. Furthermore, when analyses were stratified by factors Rhoda Ashley for conducting HSV-2 serologic testing, Mercedes potentially associated with trachoma infection (i.e., place of resi- Santamaria for review of histologic slides, and Fabrice Odefrey dence or educational status), similar associations were found be- specimen handling. tween C. trachomatis antibodies and ICC, which indicates that the associations found are not likely to be an effect of trachoma infection. References In this study of 44 patients with ICC, adenocarcinoma/adeno- 1. International Agency for Research on Cancer (IARC) Working Group on squamous carcinoma patients did not have a significantly higher the Evaluation of Carcinogenic Risks to Humans. Human papilloma- prevalence of C. trachomatis antibodies than control patients. viruses (IARC monographs on the evaluation of carcinogenic risks to Koskela et al. [19] found similar results among 32 adenocar- humans, vol 64). Lyon, France: IARC, 1995:409. 2. Puolakkainen M, Ukkonen P, Saikku P. The seroepidemiology of chlamy- cinoma patients, which were contrary to expectations because diae in Finland over the period 1971 to 1987. Epidemiol Infect 1989; of the tropism of C. trachomatis for endocervical cells. These 102:287– 95. results require confirmation with a larger sample size. 3. Schachter J, Hill EC, King EB, Coleman VR, Jones P, Meyer KF. Chlamydial In terms of biologic plausibility, genital C. trachomatis in- infection in women with cervical dysplasia. Am J Obstet Gynecol 1975; fections are clinically characterized by cervical atypia and in- 123:753– 7. 4. Kiviat N, Paavonen J, Wolner-Hanssen P, et al. Histologic manifestations flammation, as determined by cytologic, histopathologic, and of chlamydial cervicitis. In: Oriel D, Ridgway G, Schachter J, Taylor- colposcopic examinations [30, 31]. C. trachomatis infections Robinson D, Ward M, eds. Chlamydial infections: proceedings of the may induce immature metaplasia [5], and both HPV and C. 6th International Symposium on Human Chlamydial Infections. Cam- trachomatis may infect metaplastic tissue of the squamocolum- bridge, UK: Cambridge University Press, 1986:209– 12. nar junction, where cervical neoplasia arise [32]. The chronicity 5. Beatty WL, Morrison RP, Byrne GI. Persistent chlamydiae: from cell cul- ture to a paradigm for chlamydial pathogenesis. Microb Rev 1994;58: of C. trachomatis infectioninconjunctionwithHPV maybea 686– 99. more pertinent factor mediating ICC risk. 6. de Sanjose ´ S, Mun ˜ oz N, Bosch FX, et al. Sexually transmitted agents and Although a carcinogenic interaction between C. trachomatis cervical neoplasia in Colombia and Spain. Int J Cancer 1994;56: and HPV has not been directly demonstrated, in vitro data show 358– 63. that C. trachomatis may inhibit cell apoptosis [33], a contribu- 7. Ferrera A, Baay MF, Herbrink P, Figueroa M, Velema JP, Melchers WJ. A sero-epidemiological study of the relationship between sexually tory element for carcinogenesis. Alternatively, inflammatory transmitted agents and cervical cancer in Honduras. Int J Cancer 1997; cytokine responses during a chlamydial infection may produce 73:781– 5. reactive oxygen species that might cause DNA damage or modi- 8. Eluf-Neto J, Booth M, Mun ˜ oz N, Bosch FX, Meijer CJ, Walboomers JM. fication, providing a mechanistic link between chronic inflam- Human papillomavirus and invasive cervical cancer in Brazil. Br J mation and malignant transformation [34]. Other bacterial or Cancer 1994; 69:114– 9. Downloaded from https://academic.oup.com/jid/article/185/3/324/895185 by DeepDyve user on 15 July 2021 JID 2002;185 (1 February) C. trachomatis, HPV, and ICC 331 9. Ngelangel C, Mun ˜ oz N, Bosch FX, et al. Causes of cervical cancer in 23. Schiffman MH. Validation of hybridization assays: correlation of filter in the Philippines: a case-control study. J Natl Cancer Inst 1998;90: situ, dot blot and PCR with Southern blot. Lyon, France: International 43– 9. Agency for Research on Cancer (science publication) 1992; 169– 79. 10. Lacey CJ. Assessment of exposure to sexually transmitted agents other 24. Landis JR, Koch GG. The measurement of observer agreement for cate- than human papillomavirus. Lyon, France: International Agency for gorical data. Biometrics 1977; 33:159– 74. Research on Cancer (science publication), 1992:93– 105. 25. Puolakkainen M, Vesterinen E, Purola E, Saikku P, Paavonen J. Per- 11. Wang SP, Grayston JT. Microimmunofluorescence antibody responses in sistence of chlamydial antibodies after pelvic inflammatory disease. Chlamydia trachomatis infection: a review. In: Mardh PA, Holmes J Clin Microbiol 1986; 23:924– 8. KK, Oriel JD, et al., eds. Chlamydial infections. Amsterdam: Elsevier 26. Patnode D, Wang SP, Grayston JT. Persistence of Chlamydia pneumo- Biomedical Press, 1982:301– 16. niae, strain TWAR micro-immunofluorescent antibody. In: Bowie 12. Walboomers JM, Jacobs MV, Manos MM, et al. Human papillomavirus is WR, ed. Chlamydial infections. Cambridge, UK: Cambridge University a necessary cause of invasive cervical cancer worldwide. J Pathol 1999; Press, 1990:406– 10. 189:12– 9. 27. Schachter J. Human Chlamydia psittaci infection. In: Oriel D, Ridgway G, 13. Smith JS, Herrero R, Mun ˜ oz N, et al. Prevalence and risk factors for Schachter J, Taylor-Robinson D, Ward M, eds. Chlamydial infections: herpes simplex virus type 2 infection among middle-aged women in proceedings of the 6th International Symposium on Human Chlamydial Brazil and the Philippines. Sex Transm Dis 2001; 28:187– 94. Infections. Cambridge, UK: Cambridge University Press, 1986:311– 20. 14. Hosmer D, Lemeshow S. Applied logistic regression. New York: John 28. Remmink AJ, Walboomers JM, Helmerhorst TJ, et al. The presence of Wiley & Sons, 1989. persistent high-risk HPV genotypes in dysplastic cervical lesions is 15. Schmauz R, Okong P, de Villiers EM, et al. Multiple infections in cases associated with progressive disease: natural history up to 36 months. of cervical cancer from a high-incidence area in tropical Africa. Int J Int J Cancer 1995; 61:306– 11. Cancer 1989; 43:805– 9. 29. Stamm WE. Chlamydia trachomatis infections of the adult. In: Holmes 16. Dillner J, Lenner P, Lehtinen M, et al. A population-based seroepidemio- KK, Mardh PA, Sparling PF, et al., eds. Sexually transmitted diseases. logical study of cervical cancer. Cancer Res 1994; 54:134– 41. New York: McGraw-Hill, 1998:407– 18. 17. Jha PK, Beral V, Peto J, et al. Antibodies to human papillomavirus and to 30. Cevenini R, Costa S, Rumpianesi F, et al. Cytological and histopathologi- other genital infectious agents and invasive cervical cancer risk. Lancet cal abnormalities of the cervix in genital Chlamydia trachomatis infec- 1993; 341:1116– 8. tions. Br J Vener Dis 1981; 57:334– 7. 18. Hakama M, Lehtinen M, Knekt P, et al. Serum antibodies and subsequent 31. Paavonen J, Stevens CE, Wolner-Hanssen P, et al. Colposcopic manifes- cervical neoplasms: a prospective study with 12 years of follow-up. Am tations of cervical and vaginal infections. Obstet Gynecol Surv 1988; J Epidemiol 1993; 137:166– 70. 43:373– 81. 19. Koskela P, Anttila T, Bjorge T, et al. Chlamydia trachomatis infection as 32. Moscicki AB, Burt VG, Kanowitz S, Darragh T, Shiboski S. The signifi- a risk factor for invasive cervical cancer. Int J Cancer 2000; 85:35– 9. cance of squamous metaplasia in the development of low grade squa- 20. Anttila T, Saikku P, Koskela P, et al. Serotypes of Chlamydia trachomatis mous intraepithelial lesions in young women. Cancer 1999; 85:1139– 44. and risk for development of cervical squamous cell carcinoma. JAMA 33. Fan T, Lu H, Hu H, et al. Inhibition of apoptosis in chlamydia-infected 2001; 285:47– 51. cells: blockade of mitochondrial cytochrome c release and caspase acti- 21. Lehtinen M, Dillner J, Knekt P, et al. Serologically diagnosed infection with vation. J Exp Med 1998; 187:487– 96. human papillomavirus type 16 and risk for subsequent development of 34. Jaiswal M, LaRusso NF, Burgart LJ, Gores GJ. Inflammatory cytokines cervical carcinoma: nested case-control study. BMJ 1996; 312:537– 9. induce DNA damage and inhibit DNA repair in cholangiocarcinoma 22. Gravitt PE, Castle PE. Chlamydia trachomatis and cervical squamous cell cells by a nitric oxide– dependent mechanism. Cancer Res 2000;60: carcinoma. JAMA 2001; 285:1703– 4. 184– 90. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png The Journal of Infectious Diseases Unpaywall

Evidence forChlamydia trachomatisas a Human Papillomavirus Cofactor in the Etiology of Invasive Cervical Cancer in Brazil and the Philippines

Loading next page...
 
/lp/unpaywall/evidence-forchlamydia-trachomatisas-a-human-papillomavirus-cofactor-in-bhX7dgU05k

References (32)

Publisher
Unpaywall
ISSN
0022-1899
DOI
10.1086/338569
Publisher site
See Article on Publisher Site

Abstract

Downloaded from https://academic.oup.com/jid/article/185/3/324/895185 by DeepDyve user on 15 July 2021 Evidence for Chlamydia trachomatis as a Human Papillomavirus Cofactor in the Etiology of Invasive Cervical Cancer in Brazil and the Philippines 1 1 1,2 Jennifer S. Smith, Nubia Mun ˜ oz, Rolando Herrero, International Agency for Research on Cancer, Lyon, France; 3 4 1 ´ ´ Proyecto Epidemiologico Guanacaste, San Jose,Costa Rica; Jose Eluf-Neto, Corazon Ngelangel, Silvia Franceschi, 3 4 ˜ ˜ 5 6,a Universidade de Sao Paulo, Sao Paulo, Brazil; Philippine General F. Xavier Bosch, JanM.M.Walboomers, Hospital, University of the Philippines, Manila; Institu Catala and Rosanna W. Peeling 6 d’Oncologia, Barcelona, Spain; Free University Hospital, Amsterdam, The Netherlands; National Laboratory for Sexually Transmitted Diseases, Health Canada, Winnipeg, Canada Chlamydia trachomatis infection was examined as a cause of invasive cervical cancer (ICC) among women with human papillomavirus (HPV) infection. In total, 499 women with incident ICC (ICC patients) and 539 control patients from Sa ˜ o Paulo, Brazil, and Manila, the Philippines, were included. C. trachomatis antibodies were detected by microimmunofluorescence assay. Presence of HPV DNA in cervical specimens was determined by a polymerase chain reaction– based assay. C. trachomatis seropositivity was associated with sexual behavior but not with HPV infection. C. trachomatis increased the risk of squamous cervical cancer among HPV-positive women (odds ratio, 2.1; 95% confidence interval, 1.1 – 4.0). Results were similar in both countries. There was a suggestion of increasing squamous cancer risk with increasing C. trachomatis anti- body titers. This large study examined C. trachomatis and cervical cancer, taking into account the central role of HPV infection. C. trachomatis infection was found to be a possible cofactor of HPV in the etiology of squamous cervical cancer, and its effect may be mediated by chronic inflammation. Extensive data show that human papillomavirus (HPV) is the atypia [2] and cervical neoplasia [3]. Genital C. trachomatis in- central cause of cervical cancer, and high-risk HPV types are as- fections may result in chronic cervicitis, pelvic inflammatory dis- sociated with a greater disease risk [1]. Only a small proportion ease, and endometritis, whereas ocular C. trachomatis infections of women infected with HPV infection progress to invasive cer- may cause trachoma and may result in blindness in some cases. vical cancer (ICC). Thus, the development of ICC depends on Interest in genital C. trachomatis infection as a potential etio- other cofactors acting in conjunction with HPV, such as other logic factor for ICC has been related to its asymptomatic nature, sexually transmitted infections (STIs), smoking, hormones, nu- persistence if left untreated, and induction of metaplasia [4] and tritional deficiencies, or host- genetic/immunologic responses. chronic inflammation [5]. Clinical observations in the 1970s indicated that genital infec- Two epidemiologic studies examined C. trachomatis in the tion with Chlamydia trachomatis was associated with cervical etiology of ICC and in the context of HPV by using sensitive poly- merase chain reaction (PCR)– based assays for HPV DNA detec- tion [6, 7]. In a study of cervical neoplasia [6], C. trachomatis Received 10 August 2001; revised 9 October 2001; electronically published seropositivity was a significant risk factor for carcinoma in situ 17 January 2002. Presented in part: 18th International Papillomavirus Conference, Bar- in Spain and Colombia after adjusting for HPV DNA. How- celona, 23– 28 July 2000 (abstract 71). ever, when combined country analyses were restricted to HPV Informed consent was obtained from all study participants. The study DNA– positive case and control patients, C. trachomatis anti- was approved by the International Agency for Research on Cancer ethics committee and by local ethics committees in Brazil and the Philippines. bodies were not significantly associated with either in situ carci- Financial support: Conselho Nacional de Desenvolvimento Cientifico e noma or ICC. Some misclassification of HPV DNA resulting Tecnologico– Brazil (JEN-204453/88.7) and Fundac ¸a ˜odeAmparo a from the use of a first-generation PCR– based assay could not Pesquisa do Estado de Sa ˜o Paulo (90/2319-9); Rockefeller Foundation (PS 9824); European Community (CI 1-0371-F[CD]), Preventiefonds be ruled out. Another study reported no association between C. (28-1502.1); The Netherlands; World Health Organization, Division of trachomatis antibodies and cervical neoplasia after adjusting for Human Reproduction (98101). HPV DNA among women in Honduras [7]. Results restricted to Deceased. Reprints or correspondence: Dr. J. S. Smith, International Agency for HPV DNA– positive participants were not presented, although Research on Cancer, 150 Cours Albert Thomas, F-69372 Lyon Ce ´dex 08, an ELISA known to have C. trachomatis/C. pneumoniae cross- France (smith@iarc.fr). reactivity was used. To further examine the role of C. trachomatis The Journal of Infectious Diseases 2002;185:324–31 infection as a cofactor of HPV in the etiology of ICC, we present q 2002 by the Infectious Diseases Society of America. All rights reserved. results from 2 International Agency for Research on Cancer 0022-1899/2002/18503-0007$02.00 Downloaded from https://academic.oup.com/jid/article/185/3/324/895185 by DeepDyve user on 15 July 2021 JID 2002;185 (1 February) C. trachomatis, HPV, and ICC 325 at270 C without additives. Histologic slides for cancer diagnosis (IARC) ICC case-control studies conducted in Sa ˜o Paulo, Brazil, were reviewed by an expert pathologist. The stage of disease was and Manila, the Philippines. coded according to International Federation of Gynecology and Obstetrics standards. Cervical exfoliated cells were collected, by sampling the ectocervix with 2 wooden spatulas and the endocervix Methods with 2 cytobrushes, and were placed in tubes with PBS, centrifuged, This analysis is based on 2 cervical cancer case-control studies of and stored at270 C until shipment to a central laboratory for HPV 499 women with incident ICC (ICC patients) and 539 control pa- DNA testing. tients in Sa ˜o Paulo and Manila, selected as described elsewhere Laboratory procedures. Serum IgG antibody responses to C. [8, 9]. Both studies were part of an IARC multicenter case-control trachomatis were determined by a microimmunofluorescence (MIF) study and used similar protocols and questionnaires for recruitment assay, which, at present, is considered to be the most accurate sero- and data collection. logic method [10]. The antigen panel consists of purified elementary All women with ICC were newly diagnosed and had received bodies of C. trachomatis (serovar A and 3 pooled serovar groups of no previous treatment, and their ICC was histologically confirmed. BDE, CJHI, and FGK) and C. pneumoniae [11]. C. pneumoniae was Hospital-based control patients were selected and were frequency included in the antigen panel to monitor cross-reactive antibody re- age-matched to the case patients by quinquennium of age. Women sponses and to test for specificity of the C. trachomatis findings. were not eligible to participate as control patients if they had received Clinically, C. trachomatis serovars D– K are primarily associated any previous cervical cancer treatment or if they had diseases pos- with genital chlamydial infections, whereas serovars A– C are as- sibly sharing risk factors with cervical cancer (e.g., cardiovascular sociated with both hyperendemic trachoma and genital infection. or cerebrovascular disease, chronic bronchitis, emphysema, or neo- Serologic testing was done without knowledge of case-control status. plasia of the breast, reproductive or respiratory organs, anus, oral All serum samples were screened for C. trachomatis at 1 : 8 cavity, esophagus, bladder, or liver). dilution and were titered to end point. With the exceptions mentioned In Brazil, 199 ICC patients (96.6% of eligible subjects) were re- below, an IgG titer>1:8against anyof the C. trachomatis serovar cruited from 5 public hospitals and 2 cancer hospitals in Sa ˜oPaulo groups was considered to be evidence of past infection with C. tra- between June 1990 and June 1991. As hospital-based controls, 225 chomatis. An IgG titer>1 : 16 against C. pneumoniae was considered women (94.5% of those eligible) were interviewed and were selected to be evidence of past C. pneumoniae infection. Serum samples that from the 5 public hospitals. In total, 150 women with ICC (75.4% had identical titers for all C. trachomatis and C. pneumoniae species of participants; 137 with squamous and 13 with adenocarcinoma/ were also tested with C. psittaci (avian strain 6BC) to determine the adenosquamous cancer) and 173 control patients (76.9%) with chla- presence of broad Chlamydia species cross-reactivity. Serum sam- mydia serology and HPV DNA results were included in this analysis. ples with identical titers for all chlamydial species (C. trachomatis, The main diagnostic categories of Brazilian control patients were C. pneumoniae, and C. psittaci) were considered to be cross-reactive diseases of the circulatory system (21.8%), infectious and parasitic and were excluded from analyses: 7 Brazilian women (5 ICC patients diseases (12.9%), diseases of the digestive tract (12.3%), neoplasms and 2 control patients) and 4 Philippine women (2 ICC patients and 2 (9.5%), and diseases of the nervous system (8.9%). control patients) in this category were excluded. Serum samples from In the Philippines, 387 ICC patients (100% of those eligible) and 9 ICC patients and 9 control patients who were seropositive for sero- 387 control patients (98.7% of those eligible) were identified among var A and negative for all other C. trachomatis serovars were con- patients at the Philippine General Hospital in Manila between April sideredtohaveevidenceofpast C. trachomatis ocular trachoma 1991 and April 1993. A total of 349 women with ICC (90.2% of infections and were excluded from analyses. participants: 318 with squamous and 31 with adenocarcinoma/ A blinded reproducibility study was conducted by retesting a ran- adenosquamous cancer) and 366 (94.6%) control patients with chla- dom sample of 10% of the serum specimens (n ¼ 105) twice by MIF. mydia serology and HPV DNA results were included in this analy- C. trachomatis serovars A, BDE, CJHI, and FGK and C. pneumoniae sis. The main diagnostic categories of control patients from the Phi- had the following percentages of agreement: 83.9%, 87.5%, 84.8%, lippines were urinary tract infections (19.5%), benign disorders of 83.9%, and 87.5%, respectively. The k agreement for C. trachomatis the genital tract (14.3%), menstrual disorders (11.1%), and diseases positivity for the 2 repeat tests was 0.75 overall: 0.65 for case patients of the circulatory system (7.9%). Fifty-five healthy women (14.9%) and0.80for control patients. The k agreement for C. pneumoniae accompanying outpatients, with similar sociodemographic and be- positivity was 0.6 for the 2 repeat tests overall: 0.56 for case and havioral characteristics as the hospital-based control patients, 0.65 for control patients. were included as control subjects. Screening for HPV DNA was done by a PCR assay based on GP5/ Specially trained interviewers administered a standardized ques- + + 6/TS-PCR and G5 /6 primers, as described elsewhere [8, 9]. In brief, tionnaire on sociodemographic characteristics, sexual behavior, and amplification of a fragment of the b-globin gene served as an internal reproductive and contraceptive history. Participating women were control for sufficiency of each specimen for amplification. Speci- asked to provide 10 mL of blood for serologic testing of C. trachoma- mens were labeled “HPV X” for HPV-positive specimens when a tis and herpes simplex virus (HSV)-2. Blood specimens were pro- specific HPV type could not be determined. GP5/6/TS-PCR primers cessed by centrifugation at the site of collection. The separated detect sequenced HPV types 6, 11, 16, 18, 31, and 33, and unse- serum samples were placed in tubes, frozen at220 C, and shipped + + quenced HPV types at subpicogram levels. G5 /6 primers detect to Lyon, France, for storage. For HPV DNA detection, cervical exfo- liated cells from all subjects and cervical biopsy specimens from over 30 different HPV types including types 6, 11, 16, 18, 26, 31, patients were obtained. Cervical biopsy specimens were kept frozen 33– 35, 39, 40, 42– 45, 51, 52, 54, 56– 59, 61, 66, 68, 70, 72, 73, Downloaded from https://academic.oup.com/jid/article/185/3/324/895185 by DeepDyve user on 15 July 2021 326 Smith et al. JID 2002;185 (1 February) IS39, MM4, MM7, CP 6108, CP 8304, and W13b [9]. All case and Results control patient specimens labeled as HPV X were retested with + + G5 /6 primers. HPV types considered as high risk included HPV In total, we studied 455 ICC patients with squamous ICC, 16, 18, 26, 31, 33, 35, 39, 45, 51 – 53, 56, 58, 59, 66, 68, 73, IS39, 44 with adenocarcinoma/adenosquamous ICC, and 539 age- and W13b. To further investigate HPV positivity among subjects, matched control patients from Brazil and the Philippines (table we retested all HPV-negative biopsy specimens and a sample of 1). C. trachomatis seroprevalence was significantly higher among + + negative cell pellets from control patients with GP5 /6 or E7 HPV all squamous ICC patients (47.7%) than among control patients + + PCR primers [12]. With these additional G5 /6 andE7results, (22.1%; P< .0001) but was not significantly higher among adeno- HPV DNA prevalence among squamous ICC patients increased in carcinoma/adenosquamous ICC patients (29.6%) than among both Brazil (from 88.7% to 92.7%) and in the Philippines (from control patients (22.1%; P ¼ :3). The difference in seropreva- 93.8% to 95.3%). We took special precautions to minimize contami- lence between squamous ICC patients and control patients nation, as described elsewhere in detail [12]. To control for any increased with increasing C. trachomatis antibody titer. Among potential effect of HSV-2, HSV-2 antibodies were detected by use control patients, C. trachomatis seroprevalence was similar in of the Gull HSV-2 gG ELISA with Western blot confirmation of all Brazil (20.2%) and the Philippines (23.0%). C. pneumoniae sero- positive, equivocal, and borderline negative ELISA results, as de- scribed elsewhere [13]. positivity did not significantly differ between ICC patients and Because this case-control study was designed to investigate C. control patients but was lower among control participants in trachomatis as an HPV cofactor, only participants having both Brazil (68.2%) than in the Philippines (82.8%; P , :001). HPV valid C. trachomatis serology and HPV DNA results could be in- DNA positivity was significantly higher among all ICC patients cluded in this analysis. The main reason for exclusion was unavail- (93.8%) than among control patients (11.3%; P , :001). ability of HPV results due to b-globin negativity. Participating and The prevalence of C. trachomatis antibodies did not differ sig- nonparticipating women had similar sociodemographic and sexual nificantly by clinical cancer stage in either Brazil or the Philip- behavior characteristics (data not shown). pines (data not shown) or for ICC patients from the 2 countries Statistical analyses. Odds ratios (ORs) and 95% confidence in- combined (combined countries): stage I, 40.2% (n ¼ 87); stage tervals (CIs) were estimated by multiple logistic regression [14]. ORs II, 47.8% (n ¼ 180); stage III, 47.5% (n ¼ 200); and stage IV, for the association were adjusted for 4 age groups (,40, 40 – 49, 50.0% (n ¼ 4; P trend = .3). 50– 59, and>60 years), country of residence, and other confounding Table 2 shows that C. trachomatis seropositivity was signifi- factors as stated. Missing values were excluded from statistical analy- cantly associated with sexual behavioral factors among control ses. Trend tests for categorized data were conducted by assigning sequential scores to the ordered categories. patients in the age-adjusted analyses. In the multivariate model, Table 1. Seroprevalence of Chlamydia antibodies and presence of human papillomavirus (HPV) DNA among invasive cervical cancer patients and control patients, by country and overall. Brazil The Philippines Overall SQ AD All control SQ AD All control SQ AD Control Variable patients patients patients patients patients patients patients patients patients No. of women with results 137 13 173 318 31 366 455 44 539 Mean age, years 52.9 47.8 52.5 47.2 48.5 46.5 48.9 48.3 48.4 C. trachomatis seropositive 38.0 30.8 20.2 51.9 29.0 23.0 47.7 29.6 22.1 Titer 8 16.1 15.4 13.3 11.0 9.7 9.0 12.5 11.4 10.4 32 12.4 15.4 4.1 25.8 9.7 10.9 21.8 11.4 8.7 128 9.5 0.0 2.9 15.1 9.7 3.0 13.4 6.8 3.0 C. trachomatis serovar A 34.3 30.8 17.9 46.9 25.8 20.2 43.1 27.3 19.5 BED 36.5 30.8 20.2 51.3 29.0 22.7 46.8 30.0 21.9 CHIJ 30.7 30.8 14.5 46.2 19.4 19.4 41.5 22.7 17.8 FGK 26.3 23.1 13.9 44.7 22.6 17.8 39.1 22.7 16.5 C. pneumoniae seropositive 74.5 76.9 68.2 76.7 90.3 82.8 76.0 86.4 78.1 HPV DNA Positive 92.7 76.9 16.2 95.3 90.3 9.0 94.5 86.4 11.3 High risk 91.3 100.0 60.7 93.4 92.9 63.6 92.8 94.7 62.3 NOTE. AD, adenocarcinoma/adenosquamous carcinoma; SQ, squamous carcinoma. Serovar positivity not mutually exclusive. Percentage of high-risk HPV types among HPV-positive participants. Downloaded from https://academic.oup.com/jid/article/185/3/324/895185 by DeepDyve user on 15 July 2021 Table 2. Prevalence of Chlamydia trachomatis and C. pneumoniae seropositivity by selected risk factors and associated odds ratios (ORs) among control women from Brazil and the Philippines. No. of C. trachomatis No. of C. pneumoniae a b a b Risk factor women seropositive OR (95% CI) OR (95% CI) women seropositive OR (95% CI) OR Age, years ,40 123 30.1 1 1 123 71.5 1 1 40 – 49 155 19.4 0.6 (0.3–1.0) 0.4 (0.2–0.8) 155 80.0 1.9 (1.0–3.3) 1.8 (1.0–3.3) 50 –59 158 18.4 0.5 (0.3–0.9) 0.5 (0.3–0.9) 158 83.5 2.3 (1.3–4.1) 2.2 (1.2–4.2) >60 103 22.3 0.7 (0.4–1.3) 0.7 (0.3–1.4) 103 74.8 1.6 (0.9–3.0) 1.5 (0.8–3.0) P trend = .2 P trend = .3 P trend = .1 P trend = .2 Country Brazil 173 20.2 1 1 173 68.2 1 1 The Philippines 366 23.0 1.1 (0.7–1.8) 2.2 (1.2–3.9) 366 82.8 2.4 (1.6–3.7) 2.2 (1.4–3.6) Age at first sexual intercourse, years >21 286 18.2 1 1 286 78.0 1 1 17–20 190 24.2 1.4 (0.9–2.2) 1.1 (0.7–1.8) 190 78.4 1.1 (0.7–1.8) 1.2 (0.7–2.0) ,17 63 33.3 2.5 (1.3–4.6) 1.7 (0.8–3.5) 63 77.8 1.2 (0.6–2.4) 1.4 (0.7–3.1) P trend = .02 P trend = .4 P trend = .5 P trend = .4 Total lifetime sex partners 1 447 19.7 1 1 447 79.9 1 1 >2 92 33.7 2.4 (1.4–4.1) 1.6 (0.9–2.9) 92 69.6 0.7 (0.4–1.3) 0.7 (0.4–1.2) Woman reported husband had other sex partners Never 356 14.6 1 1 356 77.3 1 1 Ever/uncertain 183 36.6 3.6 (2.3–5.5) 3.2 (2.1–5.1) 183 79.8 1.3 (0.8–2.0) 1.4 (0.9–2.3) Parity 0 –1 62 21.0 1 1 62 77.4 1 1 2– 4 249 20.9 1.1 (0.5–2.2) 1.2 (0.6–2.5) 249 76.3 0.9 (0.4–1.7) 0.8 (0.4–1.6) >5 228 23.7 1.6 (0.8–3.2) 1.4 (0.6–3.0) 228 80.3 1.0 (0.5–2.0) 0.9 (0.4–1.8) P trend = .3 P trend = .4 P trend = .7 P trend = .7 Herpes simplex virus Seronegative 433 18.7 1 1 433 79.9 1 1 Seropositive 106 35.9 3.3 (1.9–5.6) 2.1 (1.1–3.8) 106 70.8 0.9 (0.5–1.4) 0.8 (0.5–1.5) NOTE. CI, confidence interval. Adjusted by age and country of residence. Adjusted by age, country of residence, and all other factors in the table. Downloaded from https://academic.oup.com/jid/article/185/3/324/895185 by DeepDyve user on 15 July 2021 328 Smith et al. JID 2002;185 (1 February) Table 3. Odds ratios (ORs) of human papillomavirus (HPV) DNA ticipants, C. trachomatis– seropositive women had a 2-fold in- positivity among control women by Chlamydia trachomatis and C. creased risk of squamous ICC (OR, 2.1; 95% CI, 1.1– 4.0). Re- pneumoniae seropositivity in Brazil and the Philippines combined. sults were similar in both countries. Elevated C. trachomatis HPV-positive/ antibody titers were associated with an increased risk of squa- HPV-negative mous cervical cancer, with a significant trend (P trend = .01). Parameter control women OR (95% CI) Further analyses controlling for age at first intercourse, number C. trachomatis IgG seronegative 45/375 1 of sex partners, parity, cytologic screening, smoking, or oral C. trachomatis IgG seropositive 16/103 1.4 (0.7–2.7) contraceptive use did not significantly affect risk estimates Seropositive titer + + (data not shown). After excluding the additional GP5 6 or 8 7/49 1.2 (0.5–2.9) 32 8/39 1.6 (0.7–3.7) E7 HPV PCR results for all HPV-negative biopsy specimens 128 1/15 P for trend = .2 and a sample of negative cell pellets from control patients, re- C. pneumoniae calculated ORs for association between C. trachomatis and ICC Seronegative 15/103 1 were not significantly different from those presented in table 4 Seropositive 46/375 1.0 (0.5–2.0) (data not shown). The presence of C. trachomatis antibodies NOTE. CI, confidence interval. was associated with an increased (2-fold) risk for squamous OR adjusted for age, country of residence, herpes simplex virus (HSV)–2 seropositivity, and husband’s no. of sex partners during marital relationship. cancer among women with high-risk HPV DNA in the com- OR adjusted for age, country of residence, HSV-2 seropositivity, hus- bined country analysis (OR, 2.4; 95% CI, 1.1– 5.4; data not band’s no. of sex partners during marital relationship, and C. trachomatis shown). The effect of C. trachomatis among HPV-negative par- seropositivity. ticipants (OR, 3.4; 95% CI, 1.4– 8.3), based on 25 HPV-nega- tive women, was consistent with that among HPV-positive participants (data not shown). C. trachomatis was positively associated with a woman’s report C. pneumoniae infection was not associated with squamous or of her husband’s sexual behavior and HSV-2 seropositivity. adenosquamous ICC in either Brazil or the Philippines (data not Women,40 years old had higher C. trachomatis seropositivity shown) or in the combined analysis of both countries. The associ- than older control patients. After controlling for sexual behavior, Filipino control participants were more likely than Brazilian control participants to be C. trachomatis seropositive. Elevated C. trachomatis antibody titers (.128) among control patients Table 4. Odds ratios (ORs) of invasive squamous cervical cancer were clearly associated with sexual behavioral factors (data not among human papillomavirus (HPV) DNA–positive study partici- shown). C. trachomatis seropositivity did not significantly differ pants, by Chlamydia trachomatis and C. pneumoniae seropositivity. by any specific diagnostic category among control participants HPV-positive patients/ (data not shown). C. pneumoniae seropositivity was not associ- HPV-positive Parameter control women OR (95% CI) ated with sexual behavior among control patients. To determine whether past C. trachomatis infection may in- C. trachomatis IgG crease the risk of being a carrier of HPV infection, we examined Brazil Seronegative 78/22 1 associations between C. trachomatis antibodies and HPV DNA Seropositive 49/6 2.5 (0.9–6.9) among control patients (table 3). Results were similar in Brazil The Philippines and the Philippines (data not shown). Neither C. trachomatis a Seronegative 147/23 1 seropositivity (OR, 1.4; 95% CI, 0.7– 2.7) nor high C. trachoma- Seropositive 156/10 1.6 (0.7–3.7) Both countries combined tis antibody titers (OR, 1.6; 95% CI, 0.7– 3.7) were significantly Seronegative 225/45 1 associated with HPV DNA detection. C. pneumoniae seroposi- Seropositive 205/16 2.1 (1.1–4.0) tivity was not associated with HPV DNA positivity among con- Seropositive titer trol patients. 8 56/7 1.4 (0.6–3.3) In relation to cervical cancer, C. trachomatis seropositivity 32 94/8 2.7 (1.2–5.9) 128 55/1 P for trend = .01 was significantly associated with squamous ICC after adjusting C. pneumoniae, both for age, HPV DNA positivity, HSV-2 seropositivity, the report- countries combined ed sexual behavior of a woman’s husband (for the combined c Seronegative 102/15 1 countries, OR, 2.5; 95% CI, 1.5– 4.1), and elevated (.32) C. Seropositive 328/46 1.2 (0.6–2.3) trachomatis antibody titers (OR, 3.9; 95% CI, 2.1– 7.3; data not NOTE. CI, confidence interval. shown). OR adjusted for age, herpes simplex virus (HSV)–2 seropositivity, and husband’s no. of sex partners during marital relationship. To more effectively control for the strong effect of HPV, analy- Combined country analyses were adjusted for country of residence. ses were restricted to squamous ICC patients and control patients OR adjusted for age, HSV-2 seropositivity, husband’s sex partners during with HPV DNA (table 4). Among all HPV DNA– positive par- marital relationship, and C. trachomatis seropositivity. Downloaded from https://academic.oup.com/jid/article/185/3/324/895185 by DeepDyve user on 15 July 2021 JID 2002;185 (1 February) C. trachomatis, HPV, and ICC 329 ations between C. trachomatis and squamous cervical cancer Our data did not show a significant association between were similar for C. pneumoniae– seropositive and – seronegative C. trachomatis seropositivity and HPV DNA positivity, which women (data not shown). may be due to the different nature of these 2 markers. Whereas On the basis of data from 44 ICC patients, C. trachomatis sero- HPV DNA indicates both current or persistent HPV infection, positivity was not associated with adenocarcinoma/adenosqua- C. trachomatis seropositivity represents a more cumulative mea- mous ICC risk in Brazil or the Philippines (data not shown) or in sure of exposure to C. trachomatis infection. the combined country analysis (OR, 0.8; 95% CI, 0.3– 2.2) The use of species-specific MIF serologic testing allows the among HPV DNA– positive participants after controlling for ascertainment of past C. trachomatis infection while differentiat- age, HSV-2 seropositivity, and a woman’s reported history of ing C. pneumoniae antibodies from C. trachomatis serovar group- her husband’s sexual behavior. ings [11]. Unlike C. pneumoniae, C. trachomatis antibodies were Analyses were conducted for each C. trachomatis serovar significantly associated with sexual behavior and with squamous group (A, BED, CHIJ, and FGK). The association between C. ICC. Results from our blinded reproducibility test showed a high trachomatis and squamous or adenocarcinoma/adenosquamous agreement between seropositivity to the different C. trachomatis ICC was similar in all serovar groups (data not shown). serovars (.83%) and “substantial” k agreement for C. trachoma- tis positivity [24] for both case and control participants. C. tracho- matis IgG antibodies may persist for years among women with Discussion acute infections [25], and antibody persistence and elevated titers We believe that our study is the largest of C. trachomatis, HPV, are considered to be related to longer, more severe, and recurrent and ICC to date that takes into account the strong effect of HPV chlamydial infections [26]. Reliable data on the natural history and type-specific C. trachomatis serology results. These data and long-term persistence of C. trachomatis antibodies are, how- indicate a moderate, but significant, association between C. ever, lacking, although the disappearance of IgG C. trachomatis trachomatis infection and ICC in the presence of HPV DNA. serum antibodies is considered to be rare in women [10, 27]. C. trachomatis seropositivity was consistently associated with Among the potential limitations of our study is the use of hos- an increased risk (2-fold)ofsquamousICC amongHPV pital-based control patients. This could have led to biased results DNA– positive participants, after adjusting for confounding if C. trachomatis seroprevalence among the control patients was factors. A pattern of increasing squamous ICC risk with increas- not representative of the population source for the ICC patients. ing C. trachomatis titers was observed, which suggests a dose- Control participants in these studies, however, had a wide range response effect. C. trachomatis was not clearly associated with of diagnostic categories and were recruited in tertiary public hos- adenocarcinoma/adenosquamous carcinoma, although this ob- pitals with wide reference populations. C. trachomatis seroposi- servation was based on a small number of cases. tivity did not differ significantly by any major diagnostic category The positive associations of squamous ICC and C. trachomatis among control patients. Although the case-control design did infection in this study (OR, 2.1) are consistent with results from not elucidate the temporal association between C. trachomatis case-control studies of ICC that have used less sensitive methods seropositivity and ICC, all ICC patients in our study were newly than PCR for HPV detection, namely, Southern blotting (OR, 4.8) diagnosed and had not received previous cervical cancer treat- ment and the frequency of C. trachomatis seropositivity did not [15] and HPV serology (OR, 1.7– 2.2) [16, 17]. Nested case- vary by the clinical stage of ICC, thus reducing the likelihood control studies have primarily found significant positive associ- ations between C. trachomatis serum antibodies and ICC (OR, that our findings may be attributed to the development of C. 1.5– 2.5) [18– 20], although one smaller study found a nonsignifi- trachomatis antibodies following the onset of invasive disease. cant 3-fold increase in ICC risk (OR, 3.0; 95% CI, 0.7– 13.4) The power of our analyses examining C. trachomatis as an [21]. However, residual confounding due to HPV in these studies HPV cofactor in the etiology of cervical cancer is also limited cannot be excluded, because less sensitive HPV serologic assays because of the small number of HPV-positive control patients. were used to assess HPV status [22]. Persistent HPV DNA infections have been associated with an Due to the notable association between HPV and ICC, a prereq- increased risk of cervical neoplasia, particularly among women uisite to evaluating an HPV cofactor is to accurately assess HPV with high-risk HPV types [28]. In this study, a cross-sectional infection. The PCR-based assay used is one of the most accurate measurement of HPV DNA was taken among case and control methods to assess cervical HPV infection [23]. Given the notably patients. The extent to which this HPV DNA measurement among high prevalence of HPV DNA in cervical cancer worldwide control patients .45 years old represents a persistent HPV in- (99%) [12], we concentrated on analyses restricted to HPV fection merits further investigation. However, C. trachomatis DNA– positive women to reduce the likelihood of residual HPV antibodies were associated with an increased squamous cancer confounding, so as to assess C. trachomatis as an HPV cofactor. risk when analyses were restricted to women who had more However, an association between C. trachomatis antibodies and persistent, high-risk DNA types. squamous ICC also emerged among HPV DNA– negative case The increasing risk of squamous cervical cancer with in- and control patients. creasing C. trachomatis antibody titers gives further support to Downloaded from https://academic.oup.com/jid/article/185/3/324/895185 by DeepDyve user on 15 July 2021 330 Smith et al. JID 2002;185 (1 February) the results found. High antibody titers may be a marker of per- parasitic infections causing chronic inflammation have also sistent C. trachomatis infection, since women with long-term been implicated in human cancer, such as Helicobacter pylori complications of chlamydial infection, such as pelvic inflam- with stomach cancer and Schistosoma haematobium with blad- matory disease or tubal infertility, have significantly higher der cancer. levels of MIF antibody than women with cervical chlamydial Our results, based on a large number of newly diagnosed ICC infection [29]. patients, consistently indicate a potential etiologic role for C. No specific C. trachomatis serovar group (A, BDE, CJHI, or trachomatis infection as an HPV cofactor in the development of FGK) was associated with a higher squamous cell cancer risk. squamous ICC. Further epidemiologic studies are needed to clar- The microbial risk factor associated with squamous cancer risk ify the role of C. trachomatis in the etiology of cervical cancer. may not be serovar specific. Alternatively, the statistical power Additional prospective data are needed on the induction of inflam- to detect meaningful differences between the associations of mation by C. trachomatis andother STIs andonthe effect of different C. trachomatis serovar groups and ICC by use of sero- their relative timing, in conjunction with HPV infection, on the logic testing may be limited because of common subspecies risk of cervical neoplasia, in addition to the effect of the treat- cross-reactivity and because women may have been infected ment of C. trachomatis infection on the progression of cervical with multiple serovars. The main shortcoming of this study is neoplasia. that, by use of BDE, CJHI, and FGK serovar group data in the MIF assay, it was not possible to distinguish clearly between Acknowledgments exposure to C. trachomatis genital infections and hyperendemic ocular trachoma infections. Notwithstanding, it is difficult to be- We are indebted to the study participants and the gynecologists, lieve that our results can be attributed to an effect of trachoma in- pathologists, and oncologists who facilitated the identification of fection, because both studies were conducted in urban centers specimens and to the field work supervisors. We thank Keerti V. Shah for critical review of this manuscript, Liz Dillon for sero- without a history of hyperendemic trachoma, and high C. tracho- logic testing of chlamydial antibodies by MIF, Chris Meijer and matis antibody titers were significantly associated with sexual Adriaan van den Brule for assisting with HPV DNA testing, behavior. Furthermore, when analyses were stratified by factors Rhoda Ashley for conducting HSV-2 serologic testing, Mercedes potentially associated with trachoma infection (i.e., place of resi- Santamaria for review of histologic slides, and Fabrice Odefrey dence or educational status), similar associations were found be- specimen handling. tween C. trachomatis antibodies and ICC, which indicates that the associations found are not likely to be an effect of trachoma infection. References In this study of 44 patients with ICC, adenocarcinoma/adeno- 1. International Agency for Research on Cancer (IARC) Working Group on squamous carcinoma patients did not have a significantly higher the Evaluation of Carcinogenic Risks to Humans. Human papilloma- prevalence of C. trachomatis antibodies than control patients. viruses (IARC monographs on the evaluation of carcinogenic risks to Koskela et al. [19] found similar results among 32 adenocar- humans, vol 64). Lyon, France: IARC, 1995:409. 2. Puolakkainen M, Ukkonen P, Saikku P. The seroepidemiology of chlamy- cinoma patients, which were contrary to expectations because diae in Finland over the period 1971 to 1987. Epidemiol Infect 1989; of the tropism of C. trachomatis for endocervical cells. These 102:287– 95. results require confirmation with a larger sample size. 3. Schachter J, Hill EC, King EB, Coleman VR, Jones P, Meyer KF. Chlamydial In terms of biologic plausibility, genital C. trachomatis in- infection in women with cervical dysplasia. Am J Obstet Gynecol 1975; fections are clinically characterized by cervical atypia and in- 123:753– 7. 4. Kiviat N, Paavonen J, Wolner-Hanssen P, et al. Histologic manifestations flammation, as determined by cytologic, histopathologic, and of chlamydial cervicitis. In: Oriel D, Ridgway G, Schachter J, Taylor- colposcopic examinations [30, 31]. C. trachomatis infections Robinson D, Ward M, eds. Chlamydial infections: proceedings of the may induce immature metaplasia [5], and both HPV and C. 6th International Symposium on Human Chlamydial Infections. Cam- trachomatis may infect metaplastic tissue of the squamocolum- bridge, UK: Cambridge University Press, 1986:209– 12. nar junction, where cervical neoplasia arise [32]. The chronicity 5. Beatty WL, Morrison RP, Byrne GI. Persistent chlamydiae: from cell cul- ture to a paradigm for chlamydial pathogenesis. Microb Rev 1994;58: of C. trachomatis infectioninconjunctionwithHPV maybea 686– 99. more pertinent factor mediating ICC risk. 6. de Sanjose ´ S, Mun ˜ oz N, Bosch FX, et al. Sexually transmitted agents and Although a carcinogenic interaction between C. trachomatis cervical neoplasia in Colombia and Spain. Int J Cancer 1994;56: and HPV has not been directly demonstrated, in vitro data show 358– 63. that C. trachomatis may inhibit cell apoptosis [33], a contribu- 7. Ferrera A, Baay MF, Herbrink P, Figueroa M, Velema JP, Melchers WJ. A sero-epidemiological study of the relationship between sexually tory element for carcinogenesis. Alternatively, inflammatory transmitted agents and cervical cancer in Honduras. Int J Cancer 1997; cytokine responses during a chlamydial infection may produce 73:781– 5. reactive oxygen species that might cause DNA damage or modi- 8. Eluf-Neto J, Booth M, Mun ˜ oz N, Bosch FX, Meijer CJ, Walboomers JM. fication, providing a mechanistic link between chronic inflam- Human papillomavirus and invasive cervical cancer in Brazil. Br J mation and malignant transformation [34]. Other bacterial or Cancer 1994; 69:114– 9. Downloaded from https://academic.oup.com/jid/article/185/3/324/895185 by DeepDyve user on 15 July 2021 JID 2002;185 (1 February) C. trachomatis, HPV, and ICC 331 9. Ngelangel C, Mun ˜ oz N, Bosch FX, et al. Causes of cervical cancer in 23. Schiffman MH. Validation of hybridization assays: correlation of filter in the Philippines: a case-control study. J Natl Cancer Inst 1998;90: situ, dot blot and PCR with Southern blot. Lyon, France: International 43– 9. Agency for Research on Cancer (science publication) 1992; 169– 79. 10. Lacey CJ. Assessment of exposure to sexually transmitted agents other 24. Landis JR, Koch GG. The measurement of observer agreement for cate- than human papillomavirus. Lyon, France: International Agency for gorical data. Biometrics 1977; 33:159– 74. Research on Cancer (science publication), 1992:93– 105. 25. Puolakkainen M, Vesterinen E, Purola E, Saikku P, Paavonen J. Per- 11. Wang SP, Grayston JT. Microimmunofluorescence antibody responses in sistence of chlamydial antibodies after pelvic inflammatory disease. Chlamydia trachomatis infection: a review. In: Mardh PA, Holmes J Clin Microbiol 1986; 23:924– 8. KK, Oriel JD, et al., eds. Chlamydial infections. Amsterdam: Elsevier 26. Patnode D, Wang SP, Grayston JT. Persistence of Chlamydia pneumo- Biomedical Press, 1982:301– 16. niae, strain TWAR micro-immunofluorescent antibody. In: Bowie 12. Walboomers JM, Jacobs MV, Manos MM, et al. Human papillomavirus is WR, ed. Chlamydial infections. Cambridge, UK: Cambridge University a necessary cause of invasive cervical cancer worldwide. J Pathol 1999; Press, 1990:406– 10. 189:12– 9. 27. Schachter J. Human Chlamydia psittaci infection. In: Oriel D, Ridgway G, 13. Smith JS, Herrero R, Mun ˜ oz N, et al. Prevalence and risk factors for Schachter J, Taylor-Robinson D, Ward M, eds. Chlamydial infections: herpes simplex virus type 2 infection among middle-aged women in proceedings of the 6th International Symposium on Human Chlamydial Brazil and the Philippines. Sex Transm Dis 2001; 28:187– 94. Infections. Cambridge, UK: Cambridge University Press, 1986:311– 20. 14. Hosmer D, Lemeshow S. Applied logistic regression. New York: John 28. Remmink AJ, Walboomers JM, Helmerhorst TJ, et al. The presence of Wiley & Sons, 1989. persistent high-risk HPV genotypes in dysplastic cervical lesions is 15. Schmauz R, Okong P, de Villiers EM, et al. Multiple infections in cases associated with progressive disease: natural history up to 36 months. of cervical cancer from a high-incidence area in tropical Africa. Int J Int J Cancer 1995; 61:306– 11. Cancer 1989; 43:805– 9. 29. Stamm WE. Chlamydia trachomatis infections of the adult. In: Holmes 16. Dillner J, Lenner P, Lehtinen M, et al. A population-based seroepidemio- KK, Mardh PA, Sparling PF, et al., eds. Sexually transmitted diseases. logical study of cervical cancer. Cancer Res 1994; 54:134– 41. New York: McGraw-Hill, 1998:407– 18. 17. Jha PK, Beral V, Peto J, et al. Antibodies to human papillomavirus and to 30. Cevenini R, Costa S, Rumpianesi F, et al. Cytological and histopathologi- other genital infectious agents and invasive cervical cancer risk. Lancet cal abnormalities of the cervix in genital Chlamydia trachomatis infec- 1993; 341:1116– 8. tions. Br J Vener Dis 1981; 57:334– 7. 18. Hakama M, Lehtinen M, Knekt P, et al. Serum antibodies and subsequent 31. Paavonen J, Stevens CE, Wolner-Hanssen P, et al. Colposcopic manifes- cervical neoplasms: a prospective study with 12 years of follow-up. Am tations of cervical and vaginal infections. Obstet Gynecol Surv 1988; J Epidemiol 1993; 137:166– 70. 43:373– 81. 19. Koskela P, Anttila T, Bjorge T, et al. Chlamydia trachomatis infection as 32. Moscicki AB, Burt VG, Kanowitz S, Darragh T, Shiboski S. The signifi- a risk factor for invasive cervical cancer. Int J Cancer 2000; 85:35– 9. cance of squamous metaplasia in the development of low grade squa- 20. Anttila T, Saikku P, Koskela P, et al. Serotypes of Chlamydia trachomatis mous intraepithelial lesions in young women. Cancer 1999; 85:1139– 44. and risk for development of cervical squamous cell carcinoma. JAMA 33. Fan T, Lu H, Hu H, et al. Inhibition of apoptosis in chlamydia-infected 2001; 285:47– 51. cells: blockade of mitochondrial cytochrome c release and caspase acti- 21. Lehtinen M, Dillner J, Knekt P, et al. Serologically diagnosed infection with vation. J Exp Med 1998; 187:487– 96. human papillomavirus type 16 and risk for subsequent development of 34. Jaiswal M, LaRusso NF, Burgart LJ, Gores GJ. Inflammatory cytokines cervical carcinoma: nested case-control study. BMJ 1996; 312:537– 9. induce DNA damage and inhibit DNA repair in cholangiocarcinoma 22. Gravitt PE, Castle PE. Chlamydia trachomatis and cervical squamous cell cells by a nitric oxide– dependent mechanism. Cancer Res 2000;60: carcinoma. JAMA 2001; 285:1703– 4. 184– 90.

Journal

The Journal of Infectious DiseasesUnpaywall

Published: Feb 1, 2002

There are no references for this article.