Get 20M+ Full-Text Papers For Less Than $1.50/day. Start a 14-Day Trial for You or Your Team.

Learn More →

Relationship between Major Histocompatibility Complex Class I Expression and Prognosis in Canine Mammary Gland Tumors

Relationship between Major Histocompatibility Complex Class I Expression and Prognosis in Canine... NOTE Pathology Relationship between Major Histocompatibility Complex Class I Expression and Prognosis in Canine Mammary Gland Tumors 1) 2) 1) 1) 1) 1) Toshiyuki TANAKA , Terumasa SHIMADA , Hideo AKIYOSHI , Junichiro SHIMIZU , Cao ZHENG , Li YIJYUN , 1) 1) 3) 4) 1) Keiichiro MIE , Akiyoshi HAYASHI , Mitsuru KUWAMURA , Fumio HOSHI and Fumihito OHASHI * 1) Laboratory of Veterinary Surgery, Department of Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1–58 Rinku-Oraikita, Izumisano, Osaka 598–8531, Japan 2) Veterinary Medical Center, Department of Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1–58 Rinku-Oraikita, Izumisano, Osaka 598–8531, Japan 3) Laboratory of Veterinary Pathology, Department of Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1–58 Rinku-Oraikita, Izumisano, Osaka 598–8531, Japan 4) Department of Small Animal Internal Medicine, School of Veterinary Medicine, Kitasato University, 23–35–1 Higashi, Towada, Aomori 034–8628, Japan (Received 13 February 2013/Accepted 17 May 2013/Published online in J-STAGE 31 May 2013) AbSTRACT . The aim of this study was to evaluate MHC class I expression and prognosis using tumor tissues surgically removed from 9 dogs with mammary gland carcinomas and from 13 dogs with complex carcinomas. We assessed MHC class I expression and its correlation with tumor size, B2M expression, infiltration of lymphocytes, histological grade and prognosis. Hematoxylin and eosin-stained sections were histologically graded using the Elston and Ellis grading method. MHC class I expression on tumor cells was evaluated using the avidin- biotin peroxidase complex method. Loss of MHC class I expression from canine mammary gland carcinomas was significantly correlated with poor prognosis (P<0.05). Loss of MHC class I expression showed no association with poor prognosis in canine mammary gland complex carcinomas, because the data were not balanced. Only 1 of 13 (7.6%) canine mammary gland complex carcinomas showed loss of MHC class I expression. All 13 of these dogs showed good prognosis. Thus, the low frequency of MHC class I expression loss from canine mammary gland complex carcinomas may be associated with good prognosis. Taken together, these results suggest that loss of MHC class I expression may be associated with poor prognosis in canine mammary gland carcinomas. KEY WORDS: beta2-microglobulin, canine, mammary gland carcinoma, MHC class I. doi: 10.1292/jvms.13-0080; J. Vet. Med. Sci. 75(10): 1393–1398, 2013 Major histocompatibility complex (MHC) class I antigens different growth patterns and biological behavior, depending are composed of both variable chain MHC class I proteins on whether the tumors are simple or complex carcinomas [9, and beta2-microglobulin (b2M) [18], an invariant chain 11]. Analysis of potentially important prognostic factors in essential for the structural stability and optimal function of canine mammary gland tumors has been the focus of many these proteins [16]. In humans, MHC class I antigens are studies. Prognostic factors in dogs with these tumors include expressed on the surface of most nucleated cells [12]. Loss tumor size, histological type, evidence of metastasis at the or downregulation of MHC class I expression has been re- time of diagnosis, clinical stage and histological grade [3, ported in many types of cancer, including breast cancer [1, 8, 17]. Although canine and human mammary gland tumors 2, 18]. The frequency of MHC class I expression loss and/or have similar features, including histological appearance and downregulation in breast cancer ranges from 37 to 88% [1, biological behavior [20], no study to date has evaluated the 18]. This loss or downregulation of MHC class I expression relationship between loss or downregulation of MHC class has been associated with disease progression and/or poor I expression and prognosis in dogs with these tumors. This clinical outcome [2]. Cells with loss of these antigen proteins study therefore assessed MHC class I expression and its from the cell surface may escape recognition by CD8 T correlations with B2M expression, tumor size, infiltration of lymphocytes [18]. Loss of MHC class I expression in breast lymphocytes, histological grade and prognosis in dogs with cancer is caused by loss of b2M expression and/or function mammary gland carcinoma and complex carcinomas. [4]. In dogs, mammary gland tumors are the second most This observational study involved 22 female dogs with commonly occurring neoplasms [13]. These tumors show mammary gland tumors, including 9 with mammary gland carcinomas and 13 with mammary gland complex carcino- mas, admitted to the Veterinary Clinical Center of Osaka *Corresponden Ce ot : Ohashi , F., Laboratory of Veterinary Sur- Prefecture University from June 2009 to October 2010. gery, Department of Graduate School of Life and Environmental Histopathological findings were used to classify the tumors Sciences, Osaka Prefecture University, 1–58 Rinku-Oraikita, according to the criteria of a recently validated system [10]. Izumisano-shi, Osaka 598–8531, Japan. Median dog age was 12 years (range 8 to 14 years). None of e-mail: ohashi@vet.osakafu-u.ac.jp the dogs had metastases. Clinical data collected for all dogs ©2013 The Japanese Society of Veterinary Science included age at diagnosis, tumor size, treatment, relapse and 1394 T. TANAKA ET AL. Fig. 1. Representative images of canine mammary gland carcinomas and complex carcinomas of histological grades 1–3. (a) Grade 1, well-differentiated tumor; (b) Grade 2, moderately differentiated tumor; (c) Grade 3, poorly differentiated tumor. Scale bar: 100 µm. survival. Dogs were followed-up for at least 2 years after at room temperature for 30 min, washed, incubated with surgical excision of the mammary gland tumors with assess- streptavidin conjugated to horseradish peroxidase (HRP) at ment of no relapse or survival, rather than the disease-free room temperature for 30 min, washed in PbS for 5 min and interval. Since different types of treatment and deaths due to developed for 5 min using a 3,3’-diaminobenzidine chromo- unrelated causes or euthanasia were considered confound- gen (DAb) H O solution. Color development was stopped 2 2 ers of survival time as an end point [6], dogs that died from by diluting in distilled deionized H O, and the sections were unrelated causes or were euthanized were excluded. All dogs counterstained with hematoxylin. Normal mammary gland or were treated by surgery only. Tumor tissue was removed and non-tumor lymph nodes of canine tissue were used as posi- subjected to histopathological and immunohistochemical tive controls. MHC class I expression score was measured analysis. The study protocol was approved by the animal as described previously [18]. MHC class I-expressing tumor ethics review committee of Osaka Prefecture University. cells were analyzed in 20 different fields of each tumor, and Hematoxylin and eosin (HE)-stained sections were histo- the values reported represent the means of the area calcu- logically graded using the Elston and Ellis grading method as lated. MHC class I expression was regarded as negative, described previously [8, 19]. Grading was based on (1) gland if immunoreactivity was observed in <10% of tumor cells. tubules and acini formation, (2) pleomorphism of tumor cell MHC class I expression was regarded as positive, if >10% of nuclei and (3) mitotic counts with each feature scored from tumor cells were stained (Fig. 2). 1 to 3 points. Tumors with 3–5, 6–7 and 8–9 points were b2M expression on tumor cells was assessed similarly us- considered as having histological grades 1 (well differenti- ing rabbit anti-dog b2M serum (10 µ g/ml; diluted 1:500), the ated), 2 (moderately differentiated) and 3 (poorly differenti- kind gift of Dr F. Hoshi (Kitasato University School of Vet- ated), respectively (Fig. 1). Infiltration of lymphocytes was erinary Medicine, Towada, Japan) [14, 15] and a commercial evaluated using HE-stained sections semiquantitatively with streptavidin-biotin kit (LSAb+ Kit/HRP; Dako). To assay − indicating no infiltration and + indicating mild, moderate B2M expression, formalin-fixed paraffin-embedded sections or diffuse infiltration. of surgical specimens were deparaffinized and boiled for 15 MHC class I expression on tumor cells was assayed us- min in a microwave oven for antigen retrieval. The sections ing mouse anti-dog MHC class I monoclonal antibody were incubated with 3% H O at room temperature for 10 2 2 (VMRD, Inc., Pullman, WA, U.S.A., diluted 1:200) and a min, washed with PbS for 5 min and incubated with 5% commercial streptavidin-biotin kit (LSAb+ Kit/HRP; Dako skimmed milk in PbS at room temperature for 60 min. The North America, Inc., Carpinteria, CA, U.S.A.). Briefly, sec- sections were subsequently incubated with optimally diluted tions, 1 cm in diameter, were embedded in optimal cutting rabbit anti-dog b2M serum at room temperature for 30 min, temperature (OCT) embedding medium (Tissue Mount; washed, incubated with biotinylated anti-mouse IgG (Dako) Chiba Medical Co., Ltd., Saitama, Japan), frozen in liquid at room temperature for 15 min and again washed. The sec- nitrogen and stored at −80°C until use. Cryostat sections tions were incubated with streptavidin conjugated to HRP were cut, air dried at room temperature, fixed in acetone at room temperature for 15 min, washed in PbS for 5 min, for 10 min at room temperature and washed with 0.01 M developed for 3 min in DAb H O and counterstained with 2 2 phosphate-buffered saline (PbS; pH 7.4) for 5 min. The sec- hematoxylin. Normal mammary gland or non-tumor lymph tions were incubated with 3% H O at room temperature for nodes of dogs were used as positive controls. b2M expres- 2 2 3 min, washed with PbS for 5 min and incubated with 1.5% sion score was measured as above (Fig. 2). skimmed milk in PbS at room temperature for 60 min. After All statistical analyses were performed using R software washing, these sections were incubated with optimally di- (version 2.12.1). Continuous variables were assessed using luted monoclonal antibodies for 30 min at room temperature Fisher’s exact test with statistical significance set at P <0.05. and washed; isotypic IgG was used as a negative control. To To assist in determining between-group differences, effect detect MHC class I-positive cells, the sections were subse- size statistics were calculated for each dependent variable. quently incubated with biotinylated anti-mouse IgG (Dako) An effect size (Cramer’s coefficient of association) of 0.5 MHC CLASS I AND PROGNOSIS IN CANINE MGT 1395 Fig. 2. Representative images of (a) negative score for MHC class I expression on mammary gland carcinoma, (b) positive score for MHC class I expression on mammary gland carcinoma, (c) negative score for b2M expression on mammary gland carcinoma and (d) positive score for b2M expression on mammary gland carcinoma. Scale bar: 100 µm. was defined as a meaningful between-group difference. the effect size statistic was large (0.63), suggesting that loss MHC class I expression score was categorized as negative or of MHC class I expression was significantly associated with positive; tumor size was classified as >3 cm or <3 cm; B2M loss of b2M expression (Table 1). Of the 5 tumors positive expression was classified as negative or positive; infiltration for MHC class I expression, 3 (60%) were positive, and of lymphocytes was classified as negative or positive; his- 2 (40%) were negative for infiltration of lymphocytes. Of tological grade was classified as 1, 2 or 3; and disease-free the 4 dogs with negative scores for MHC class I expres- interval was classified as >24 months or <24 months. sion, 0 (0%) and 4 (100%) were positive and negative for In 9 dogs with mammary gland carcinomas, the histologi- infiltration of lymphocytes, respectively. Fisher’s exact test cal grade was 1 in 1 dogs (11%), 2 in 3 dogs (33%) and 3 in revealed no significant association between MHC class I and 5 dogs (56%). Immunohistochemical analysis of MHC class infiltration of lymphocytes (Table 1). However, the effect I expression in mammary gland carcinomas showed that 5 size statistic was large (0.63), suggesting that loss of MHC dogs had a positive score and 4 dogs had a negative score. class I expression was significantly associated with infiltra- Regarding MHC class I expression, immunoreactivity was tion of lymphocytes (Table 1). Of the 5 tumors positive for observed in the membrane and cytoplasm. Tumors from MHC class I expression, 1 (20%), 3 (60%) and 1 (20%) were 4 of the 9 dogs (44.4%) had lost MHC class I expression of histological grades 1, 2 and 3, respectively, whereas the (Table 1). Of the 5 dogs with positive scores for MHC class tumors of all 4 dogs negative for MHC class I expression I expression, 4 (80%) had tumors >3 cm in size, and 1 (20%) were of histological grade 3. Fisher’s exact test showed that had a tumor <3 cm in size. Of the 4 dogs with negative MHC class I expression was not significantly associated scores for MHC class I expression, 3 (75%) and 1 (25%) with histological grade (Table 1). However, the effect size had tumors >3 cm and <3 cm in size, respectively. Fisher’s statistic was large (0.8), suggesting that loss of MHC class exact test showed no significant association between MHC I expression was associated with higher histological grade class I expression and tumor size (Table 1). Of the 5 tumors (Table 1). Staining intensity had no association with histo- positive for MHC class I expression, 3 (60%) were positive, logical grade. All 5 dogs positive for MHC class I expression and 2 (40%) were negative for b2M expression. Regarding survived without relapse or shortened survival for 2 years b2M expression, immunoreactivity was observed in the after surgical treatment. In contrast, all 4 dogs negative for membrane and cytoplasm. All 4 tumors negative for MHC MHC class I expression relapsed or died during the 2 years class I expression were also negative for b2M expression. after surgical treatment (median survival, 3.5 months; range, Fisher’s exact test revealed no significant association be- 1 to 6). Fisher’s exact test showed a significant relationship tween MHC class I and b2M expression (Table 1). However, between loss of MHC class I expression and shorter event- 1396 T. TANAKA ET AL. Table 1. MHC class I expression, tumor size, B2M expression, infiltration of lymphocytes, histological grade and event-free intervals in dogs with mammary gland and mammary gland complex carcinomas MHC class I expression MHC class I expression in mammary gland carcinoma in mammary gland complex carcinoma Positive Negative P Positive Negative P n (%) n (%) Effect size n (%) n (%) Effect size Tumor size >3 cm 4 (80) 3 (75) 0.72 6 (50) 1 (100) 1 <3 cm 1 (20) 1 (25) 0.05 6 (50) 0 (0) 0.26 b2M expression Positive 3 (60) 0 (0) 0.12 11 (92) 1 (100) 1 Negative 2 (40) 4 (100) 0.63 1 (8) 0 (0) 0.08 Infiltration of lymphocytes Positive 3 (60) 0 (0) 0.12 10 (83) 0 (0) 0.23 Negative 2 (40) 4 (100) 0.63 2 (17) 1 (100) 0.53 Histological grade 1 1 (20) 0 (0) 0.09 6 (50) 1 (100) 1 2 3 (60) 0 (0) 0.8 4 (33) 0 (0) 0.26 3 1 (20) 4 (100) 2 (17) 0 (0) Event-free interval >24 months 5 (100) 0 (0) 0.008 12 (100) 1 (100) 1 <24 months 0 (0) 4 (100) 1 0 (0) 0 (0) - P was calculated using Fisher’s exact test with statistical significance set at P<0.05. An effect size of 0.5 was identified as a meaningful difference between groups. free interval (Table 1, P<0.05). effect size statistic was large (0.53), suggesting that loss of In the 13 dogs with mammary gland complex carcinomas, MHC class I expression was significantly associated with in- the histological grades was 1 in 7 dogs (54%), 2 in 4 dogs filtration of lymphocytes (Table 1). Of the 12 tumors positive (31%) and 3 in 2 dogs (15%). Immunohistochemical analy- for MHC class I expression, 6 (50%), 4 (33%) and 2 (17%) sis of the 13 mammary gland complex carcinomas showed were of histological grades 1, 2 and 3, respectively. The tu- that 12 (92.4%) were positive and 1 (7.6%) was negative for mor negative for MHC class I expression was of histological MHC class I expression. Regarding MHC class I expression, grade 1. Fisher’s exact test and the small effect size statistic immunoreactivity of luminal epithelial cells was observed (0.26) indicated no significant association between MHC in the membrane and cytoplasm. Immunoreactivity of myo- class I expression and histological grade (Table 1). Staining epithelial cells was the same as that of luminal epithelial intensity had no association with histological grade. All 12 cells. Of the 12 tumors positive for MHC class I expression, dogs with tumors positive for MHC class I expression and 6 (50%) each had tumors >3 cm and <3 cm in size, although the 1 dog with a tumor negative for MHC class I expression the tumor negative for MHC class I expression was >3 cm in survived without relapse for 2 years after surgical treat- size. Fisher’s exact test showed that the association between ment. Fisher’s exact test showed no significant association MHC class I expression and tumor size was not statistically between loss of MHC class I expression and the event-free significant (Table 1). Immunohistochemical analysis of the interval (Table 1). 12 tumors positive for MHC class I expression showed that Previously reported prognostic factors in dogs with mam- 11 (92%) were positive for b2M expression and 1 (8%) was mary gland tumors included tumor size, histological type, negative. Regarding b2M expression, immunoreactivity of evidence of metastasis at the time of diagnosis, clinical stage luminal epithelial cells was observed in the membrane and and histological grading using the Elston and Ellis grading cytoplasm. Immunoreactivity of myoepithelial cells was the method [3, 8, 17]. This study showed that loss of MHC class same as that of luminal epithelial cells. The tumor negative I expression from canine mammary gland carcinomas was for MHC class I expression was positive for b2M expression. associated with loss of b2M expression and prognosis. In Fisher’s exact test and the small effect size statistic (0.08) human cancers, abnormalities in MHC class I expression indicated that MHC class I expression and b2M expression can be caused by alterations in the MHC class I processing were not significantly associated (Table 1). Of the 12 tumors machinery, including TAP1, TAP2, tapasin, LMP2, LMP7 positive for MHC class I expression, 10 (83%) were positive, and b2M [2]. In human breast cancer, loss of MHC class and 2 (17%) were negative for infiltration of lymphocytes. I expression is caused by loss of b2M expression and/or The 1 dog with negative scores for MHC class I expression function [4]. Tumor cells that do not express MHC class I was negative for infiltration of lymphocytes. Fisher’s exact proteins on their surfaces can escape recognition by CD8 test revealed no significant association between MHC class T lymphocytes [18]. Thus, loss or downregulation of MHC I and infiltration of lymphocytes (Table 1). However, the class I expression has been associated with disease progres- MHC CLASS I AND PROGNOSIS IN CANINE MGT 1397 sion and/or poor clinical outcome [2]. Our study showed that REFERENCES positive expression of MHC class I and infiltration of lym- phocytes in canine mammary gland carcinoma and complex 1. Aptsiauri, N., Cabrera, T., Garcia-Lora, A., Lopez-Nevot, M. A., carcinoma were correlated. Moreover, infiltration by CD8 Ruiz-Cabello, F. and Garrido, F. 2007. MHC class I antigens and T-cells in canine mammary gland carcinoma has been found immune surveillance in transformed cells. Int. Rev. Cytol. 256: 139–189. [Medline] [CrossRef] to be a marker of good prognosis [5]. Therefore, in dogs with 2. Chang, C. C., Campoli, M. and Ferrone, S. 2003. HLA class mammary gland carcinoma, loss of MHC class I expression I defects in malignant lesions: what have we learned? Keio J. may correlate with poor prognosis. Loss of MHC class I Med. 52: 220–229. [Medline] [CrossRef] expression was observed in canine mammary gland carcino- 3. Chang, S. C., Chang, C. C., Chang, T. J. and Wong, M. L. 2005. mas of histological grade 3. Histological grading is related to Prognostic factors associated with survival two years after prognosis, being worse in dogs with grade 3 (poorly differ- surgery in dogs with malignant mammary tumors: 79 cases entiated) than in those with grade 1 (well differentiated) and (1998–2002). J. Am. Vet. Med. Assoc. 227: 1625–1629. [Med- 2 (moderately differentiated) mammary gland carcinomas line] [CrossRef] [8]. MHC class I expression may be lost in poorly differenti- 4. Chen, H. L., Gabrilovich, D., Virmani, A., Ratnani, I., Girgis, ated mammary gland carcinomas. Therefore, MHC class I K. R., Nadaf-Rahrov, S., Fernandez-Viña, M. and Carbone, D. P. 1996. Structural and functional analysis of β2 microglobulin expression loss may be correlated with poor prognosis. abnormalities in human lung and breast cancer. Int. J. Cancer In this study, dogs with mammary gland complex carci- 67: 756–763. [Medline] noma had a good prognosis. However, only 1 of these 13 5. Estrela-Lima, A., Araújo, M. S., Costa-Neto, J. M., Teixeira-Car- dogs showed loss of MHC class I expression. because of this valho, A., barrouin-Melo, S. M., Cardoso, S. V., Martins-Filho, imbalance, loss of MHC class I expression from these tumors O. A., Serakides, R. and Cassali, G. D. 2010. Immunophenotypic was not associated with loss of b2M expression, histological features of tumor infiltrating lymphocytes from mammary car - grade or prognosis. Tumors in 12 of the 13 dogs with mam- cinomas in female dogs associated with prognostic factors and mary gland complex carcinoma (12/13) showed expression survival rates. BMC Cancer 10: 256. [Medline] [CrossRef] of MHC class I, and all of these dogs had a good prognosis. 6. Gilbertson, S. R., Kurzman, I. D., Zachrau, R. E., Hurvitz, A. I. Thus, the prognosis of dogs with mammary gland tumors and black, M. M. 1983. Canine mammary epithelial neoplasms: biologic implications of morphologic characteristics assessed in is associated with both histological grade and tumor type. 232 dogs. Vet. Pathol. 20: 127–142. [Medline] Dogs with carcinomas had a poorer prognosis (death rate 7. Hsieh, C. H., Hsu, Y. J., Chang, C. C., Liu, H. C., Chuang, K. L., 67.3%) than dogs with complex carcinomas (death rate 0%) Chuang, C. K., Pang, S. T., Hasumi, K., Ferrone, S. and Liao, S. [8]. The low frequency of loss of MHC class I expression in K. 2009. Total HLA class I loss in a sarcomatoid renal carcinoma dogs with mammary gland complex carcinoma may be asso- cell line caused by the coexistence of distinct mutations in the ciated with the absence of relapse or prolonged survival after two encoding beta2-microglobulin genes. Cancer Immunol. Im- surgical treatment. This study had some limitations, includ- munother. 58: 395–408. [Medline] [CrossRef] ing the small study sample and the imbalanced data in dogs 8. Karayannopoulou, M., Kaldrymidou, E., Constantinidis, T. C. with mammary gland complex carcinoma. Further work is and Dessiris, A. 2005. Histological grading and prognosis in needed to evaluate the association between loss of MHC dogs with mammary carcinomas: application of a human grading method. J. Comp. Pathol. 133: 246–252. [Medline] [CrossRef] class I expression and loss of b2M expression, histological 9. Misdorp, W. and Hart, A. A. 1976. Prognostic factors in canine grade, infiltration of CD8 T lymphocytes and prognosis in a mammary cancer. J. Natl. Cancer Inst. 56: 779–786. [Medline] larger and better balanced population of dogs with mammary 10. Misdorp, W., Else, R. W., Hellmén, E. and Lipscomb, T. P. 1999. gland complex carcinomas. Histological classification of mammary tumors of the dog and Canine mammary gland tumors >3 cm in size have been the cat. pp. 11–29. In: Armed Forces Institute of Pathology associated with poor prognosis [17]. In this study, loss of and the American Registry of Pathology and the World Health MHC class I expression was not associated with tumor size Organization Collaborating Center for Worldwide Reference on in dogs with mammary gland and complex carcinomas. In Comparative Oncology, vol. 7, Washington, D.C. humans, loss of MHC class I expression from tumor cells 11. Misdorp, W., Cotchin, E., Hampe, J. F., Jabara, A. G. and Von occurs when the primary tumor penetrates the basal mem- Sandersleben, J. 1973. Canine malignant mammary tumors. 3. Special types of carcinomas, malignant mixed tumors. Vet. branes, invading surrounding tissues and/or starts to metas- Pathol. 10: 241–256. [Medline] [CrossRef] tasize to regional lymph nodes or distant organs [7]. None 12. Morrison, L. A., Lukacher, A. E., braciale, V. L., Fan, D. P. and of the dogs in our study showed any evidence of metastasis. braciale, T. J. 1986. Differences in antigen presentation to MHC Therefore, loss of MHC class I expression may be indepen- class I- and class II-restricted influenza virus-specific cytolytic T dent of tumor size. lymphocyte clones. J. Exp. Med. 163: 903–921. [CrossRef] This study is limited by the small sample size. In future 13. Moulton, J. E. 1990. Tumor of the mammary gland. pp. 518–552. studies, a larger number of mammary gland tumors should In: Tumors in Domestic Animals. 3rd ed. (Moulton, J. E. ed.), be evaluated with regard to loss of MHC class I expression Univ. California Press, berkeley. as an independent prognostic factor by multivariate analysis, 14. Nakajima, Y., Hoshi, F., Higuchi, S. and Kawamura, S. 1999. and the mechanism of MHC class I expression loss should The complete amino acid sequence of dog beta2-microglobulin. J. Vet. Med. Sci. 61: 517–521. [Medline] [CrossRef] also be explored. In conclusion, our findings suggested that 15. Nakajima, Y., Hoshi, F., Higuchi, S. and Kawamura, S. 2001. loss of MHC class I expression may be a factor associated Determination of canine beta2-microgloblin in plasma and urine with poor prognosis in dogs with mammary gland carcinoma. 1398 T. TANAKA ET AL. by enzyme-linked immunosorbent assay. J. Vet. Med. Sci. 63: E., Serrano, A. and Morell, M. 2003. Major histocompatibility 343–345. [Medline] [CrossRef] complex status in breast carcinogenesis and relationship to apop- 16. Pedersen, L. O., Hansen, A. S., Olsen, A. C., Gerwien, J., Nissen, tosis. Hum. Pathol. 34: 1283–1289. [Medline] [CrossRef] M. H. and buus, S. 1994. The interaction between beta 2-mi- 19. Saleh, F. and Abdeen, S. 2007. Pathobiological features of breast croglobulin (beta 2m) and purified class-I major histocompat- tumours in the State of Kuwait: a comprehensive analysis. J. ibility (MHC) antigen. Scand. J. Immunol. 39: 64–72. [Medline] Carcinog. 6: 12. [Medline] [CrossRef] [CrossRef] 20. Uva, P., Aurisicchio, L., Watters, J., Loboda, A., Kulkarni, A., 17. Philibert, J. C., Snyder, P. W., Glickman, N., Glickman, L. T., Castle, J., Palombo, F., Viti, V., Mesiti, G., Zappulli, V., Mar- Knapp, D. W. and Waters, D. J. 2003. Influence of host factors conato, L., Abramo, F., Ciliberto, G., Lahm, A., La Monica, on survival in dogs with malignant mammary gland tumors. J. N. and de Rinaldis, E. 2009. Comparative expression pathway Vet. Intern. Med. 17: 102–106. [Medline] [CrossRef] analysis of human and canine mammary tumors. BMC Genomics 18. Redondo, M., Garcia, J., Villar, E., Rodrigo, I., Perea-Milla, 10: 135. [Medline] [CrossRef] http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Journal of Veterinary Medical Science Pubmed Central

Relationship between Major Histocompatibility Complex Class I Expression and Prognosis in Canine Mammary Gland Tumors

Loading next page...
 
/lp/pubmed-central/relationship-between-major-histocompatibility-complex-class-i-EQZ0uMETOc

References (23)

Publisher
Pubmed Central
Copyright
©2013 The Japanese Society of Veterinary Science
ISSN
0916-7250
eISSN
1347-7439
DOI
10.1292/jvms.13-0080
Publisher site
See Article on Publisher Site

Abstract

NOTE Pathology Relationship between Major Histocompatibility Complex Class I Expression and Prognosis in Canine Mammary Gland Tumors 1) 2) 1) 1) 1) 1) Toshiyuki TANAKA , Terumasa SHIMADA , Hideo AKIYOSHI , Junichiro SHIMIZU , Cao ZHENG , Li YIJYUN , 1) 1) 3) 4) 1) Keiichiro MIE , Akiyoshi HAYASHI , Mitsuru KUWAMURA , Fumio HOSHI and Fumihito OHASHI * 1) Laboratory of Veterinary Surgery, Department of Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1–58 Rinku-Oraikita, Izumisano, Osaka 598–8531, Japan 2) Veterinary Medical Center, Department of Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1–58 Rinku-Oraikita, Izumisano, Osaka 598–8531, Japan 3) Laboratory of Veterinary Pathology, Department of Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1–58 Rinku-Oraikita, Izumisano, Osaka 598–8531, Japan 4) Department of Small Animal Internal Medicine, School of Veterinary Medicine, Kitasato University, 23–35–1 Higashi, Towada, Aomori 034–8628, Japan (Received 13 February 2013/Accepted 17 May 2013/Published online in J-STAGE 31 May 2013) AbSTRACT . The aim of this study was to evaluate MHC class I expression and prognosis using tumor tissues surgically removed from 9 dogs with mammary gland carcinomas and from 13 dogs with complex carcinomas. We assessed MHC class I expression and its correlation with tumor size, B2M expression, infiltration of lymphocytes, histological grade and prognosis. Hematoxylin and eosin-stained sections were histologically graded using the Elston and Ellis grading method. MHC class I expression on tumor cells was evaluated using the avidin- biotin peroxidase complex method. Loss of MHC class I expression from canine mammary gland carcinomas was significantly correlated with poor prognosis (P<0.05). Loss of MHC class I expression showed no association with poor prognosis in canine mammary gland complex carcinomas, because the data were not balanced. Only 1 of 13 (7.6%) canine mammary gland complex carcinomas showed loss of MHC class I expression. All 13 of these dogs showed good prognosis. Thus, the low frequency of MHC class I expression loss from canine mammary gland complex carcinomas may be associated with good prognosis. Taken together, these results suggest that loss of MHC class I expression may be associated with poor prognosis in canine mammary gland carcinomas. KEY WORDS: beta2-microglobulin, canine, mammary gland carcinoma, MHC class I. doi: 10.1292/jvms.13-0080; J. Vet. Med. Sci. 75(10): 1393–1398, 2013 Major histocompatibility complex (MHC) class I antigens different growth patterns and biological behavior, depending are composed of both variable chain MHC class I proteins on whether the tumors are simple or complex carcinomas [9, and beta2-microglobulin (b2M) [18], an invariant chain 11]. Analysis of potentially important prognostic factors in essential for the structural stability and optimal function of canine mammary gland tumors has been the focus of many these proteins [16]. In humans, MHC class I antigens are studies. Prognostic factors in dogs with these tumors include expressed on the surface of most nucleated cells [12]. Loss tumor size, histological type, evidence of metastasis at the or downregulation of MHC class I expression has been re- time of diagnosis, clinical stage and histological grade [3, ported in many types of cancer, including breast cancer [1, 8, 17]. Although canine and human mammary gland tumors 2, 18]. The frequency of MHC class I expression loss and/or have similar features, including histological appearance and downregulation in breast cancer ranges from 37 to 88% [1, biological behavior [20], no study to date has evaluated the 18]. This loss or downregulation of MHC class I expression relationship between loss or downregulation of MHC class has been associated with disease progression and/or poor I expression and prognosis in dogs with these tumors. This clinical outcome [2]. Cells with loss of these antigen proteins study therefore assessed MHC class I expression and its from the cell surface may escape recognition by CD8 T correlations with B2M expression, tumor size, infiltration of lymphocytes [18]. Loss of MHC class I expression in breast lymphocytes, histological grade and prognosis in dogs with cancer is caused by loss of b2M expression and/or function mammary gland carcinoma and complex carcinomas. [4]. In dogs, mammary gland tumors are the second most This observational study involved 22 female dogs with commonly occurring neoplasms [13]. These tumors show mammary gland tumors, including 9 with mammary gland carcinomas and 13 with mammary gland complex carcino- mas, admitted to the Veterinary Clinical Center of Osaka *Corresponden Ce ot : Ohashi , F., Laboratory of Veterinary Sur- Prefecture University from June 2009 to October 2010. gery, Department of Graduate School of Life and Environmental Histopathological findings were used to classify the tumors Sciences, Osaka Prefecture University, 1–58 Rinku-Oraikita, according to the criteria of a recently validated system [10]. Izumisano-shi, Osaka 598–8531, Japan. Median dog age was 12 years (range 8 to 14 years). None of e-mail: ohashi@vet.osakafu-u.ac.jp the dogs had metastases. Clinical data collected for all dogs ©2013 The Japanese Society of Veterinary Science included age at diagnosis, tumor size, treatment, relapse and 1394 T. TANAKA ET AL. Fig. 1. Representative images of canine mammary gland carcinomas and complex carcinomas of histological grades 1–3. (a) Grade 1, well-differentiated tumor; (b) Grade 2, moderately differentiated tumor; (c) Grade 3, poorly differentiated tumor. Scale bar: 100 µm. survival. Dogs were followed-up for at least 2 years after at room temperature for 30 min, washed, incubated with surgical excision of the mammary gland tumors with assess- streptavidin conjugated to horseradish peroxidase (HRP) at ment of no relapse or survival, rather than the disease-free room temperature for 30 min, washed in PbS for 5 min and interval. Since different types of treatment and deaths due to developed for 5 min using a 3,3’-diaminobenzidine chromo- unrelated causes or euthanasia were considered confound- gen (DAb) H O solution. Color development was stopped 2 2 ers of survival time as an end point [6], dogs that died from by diluting in distilled deionized H O, and the sections were unrelated causes or were euthanized were excluded. All dogs counterstained with hematoxylin. Normal mammary gland or were treated by surgery only. Tumor tissue was removed and non-tumor lymph nodes of canine tissue were used as posi- subjected to histopathological and immunohistochemical tive controls. MHC class I expression score was measured analysis. The study protocol was approved by the animal as described previously [18]. MHC class I-expressing tumor ethics review committee of Osaka Prefecture University. cells were analyzed in 20 different fields of each tumor, and Hematoxylin and eosin (HE)-stained sections were histo- the values reported represent the means of the area calcu- logically graded using the Elston and Ellis grading method as lated. MHC class I expression was regarded as negative, described previously [8, 19]. Grading was based on (1) gland if immunoreactivity was observed in <10% of tumor cells. tubules and acini formation, (2) pleomorphism of tumor cell MHC class I expression was regarded as positive, if >10% of nuclei and (3) mitotic counts with each feature scored from tumor cells were stained (Fig. 2). 1 to 3 points. Tumors with 3–5, 6–7 and 8–9 points were b2M expression on tumor cells was assessed similarly us- considered as having histological grades 1 (well differenti- ing rabbit anti-dog b2M serum (10 µ g/ml; diluted 1:500), the ated), 2 (moderately differentiated) and 3 (poorly differenti- kind gift of Dr F. Hoshi (Kitasato University School of Vet- ated), respectively (Fig. 1). Infiltration of lymphocytes was erinary Medicine, Towada, Japan) [14, 15] and a commercial evaluated using HE-stained sections semiquantitatively with streptavidin-biotin kit (LSAb+ Kit/HRP; Dako). To assay − indicating no infiltration and + indicating mild, moderate B2M expression, formalin-fixed paraffin-embedded sections or diffuse infiltration. of surgical specimens were deparaffinized and boiled for 15 MHC class I expression on tumor cells was assayed us- min in a microwave oven for antigen retrieval. The sections ing mouse anti-dog MHC class I monoclonal antibody were incubated with 3% H O at room temperature for 10 2 2 (VMRD, Inc., Pullman, WA, U.S.A., diluted 1:200) and a min, washed with PbS for 5 min and incubated with 5% commercial streptavidin-biotin kit (LSAb+ Kit/HRP; Dako skimmed milk in PbS at room temperature for 60 min. The North America, Inc., Carpinteria, CA, U.S.A.). Briefly, sec- sections were subsequently incubated with optimally diluted tions, 1 cm in diameter, were embedded in optimal cutting rabbit anti-dog b2M serum at room temperature for 30 min, temperature (OCT) embedding medium (Tissue Mount; washed, incubated with biotinylated anti-mouse IgG (Dako) Chiba Medical Co., Ltd., Saitama, Japan), frozen in liquid at room temperature for 15 min and again washed. The sec- nitrogen and stored at −80°C until use. Cryostat sections tions were incubated with streptavidin conjugated to HRP were cut, air dried at room temperature, fixed in acetone at room temperature for 15 min, washed in PbS for 5 min, for 10 min at room temperature and washed with 0.01 M developed for 3 min in DAb H O and counterstained with 2 2 phosphate-buffered saline (PbS; pH 7.4) for 5 min. The sec- hematoxylin. Normal mammary gland or non-tumor lymph tions were incubated with 3% H O at room temperature for nodes of dogs were used as positive controls. b2M expres- 2 2 3 min, washed with PbS for 5 min and incubated with 1.5% sion score was measured as above (Fig. 2). skimmed milk in PbS at room temperature for 60 min. After All statistical analyses were performed using R software washing, these sections were incubated with optimally di- (version 2.12.1). Continuous variables were assessed using luted monoclonal antibodies for 30 min at room temperature Fisher’s exact test with statistical significance set at P <0.05. and washed; isotypic IgG was used as a negative control. To To assist in determining between-group differences, effect detect MHC class I-positive cells, the sections were subse- size statistics were calculated for each dependent variable. quently incubated with biotinylated anti-mouse IgG (Dako) An effect size (Cramer’s coefficient of association) of 0.5 MHC CLASS I AND PROGNOSIS IN CANINE MGT 1395 Fig. 2. Representative images of (a) negative score for MHC class I expression on mammary gland carcinoma, (b) positive score for MHC class I expression on mammary gland carcinoma, (c) negative score for b2M expression on mammary gland carcinoma and (d) positive score for b2M expression on mammary gland carcinoma. Scale bar: 100 µm. was defined as a meaningful between-group difference. the effect size statistic was large (0.63), suggesting that loss MHC class I expression score was categorized as negative or of MHC class I expression was significantly associated with positive; tumor size was classified as >3 cm or <3 cm; B2M loss of b2M expression (Table 1). Of the 5 tumors positive expression was classified as negative or positive; infiltration for MHC class I expression, 3 (60%) were positive, and of lymphocytes was classified as negative or positive; his- 2 (40%) were negative for infiltration of lymphocytes. Of tological grade was classified as 1, 2 or 3; and disease-free the 4 dogs with negative scores for MHC class I expres- interval was classified as >24 months or <24 months. sion, 0 (0%) and 4 (100%) were positive and negative for In 9 dogs with mammary gland carcinomas, the histologi- infiltration of lymphocytes, respectively. Fisher’s exact test cal grade was 1 in 1 dogs (11%), 2 in 3 dogs (33%) and 3 in revealed no significant association between MHC class I and 5 dogs (56%). Immunohistochemical analysis of MHC class infiltration of lymphocytes (Table 1). However, the effect I expression in mammary gland carcinomas showed that 5 size statistic was large (0.63), suggesting that loss of MHC dogs had a positive score and 4 dogs had a negative score. class I expression was significantly associated with infiltra- Regarding MHC class I expression, immunoreactivity was tion of lymphocytes (Table 1). Of the 5 tumors positive for observed in the membrane and cytoplasm. Tumors from MHC class I expression, 1 (20%), 3 (60%) and 1 (20%) were 4 of the 9 dogs (44.4%) had lost MHC class I expression of histological grades 1, 2 and 3, respectively, whereas the (Table 1). Of the 5 dogs with positive scores for MHC class tumors of all 4 dogs negative for MHC class I expression I expression, 4 (80%) had tumors >3 cm in size, and 1 (20%) were of histological grade 3. Fisher’s exact test showed that had a tumor <3 cm in size. Of the 4 dogs with negative MHC class I expression was not significantly associated scores for MHC class I expression, 3 (75%) and 1 (25%) with histological grade (Table 1). However, the effect size had tumors >3 cm and <3 cm in size, respectively. Fisher’s statistic was large (0.8), suggesting that loss of MHC class exact test showed no significant association between MHC I expression was associated with higher histological grade class I expression and tumor size (Table 1). Of the 5 tumors (Table 1). Staining intensity had no association with histo- positive for MHC class I expression, 3 (60%) were positive, logical grade. All 5 dogs positive for MHC class I expression and 2 (40%) were negative for b2M expression. Regarding survived without relapse or shortened survival for 2 years b2M expression, immunoreactivity was observed in the after surgical treatment. In contrast, all 4 dogs negative for membrane and cytoplasm. All 4 tumors negative for MHC MHC class I expression relapsed or died during the 2 years class I expression were also negative for b2M expression. after surgical treatment (median survival, 3.5 months; range, Fisher’s exact test revealed no significant association be- 1 to 6). Fisher’s exact test showed a significant relationship tween MHC class I and b2M expression (Table 1). However, between loss of MHC class I expression and shorter event- 1396 T. TANAKA ET AL. Table 1. MHC class I expression, tumor size, B2M expression, infiltration of lymphocytes, histological grade and event-free intervals in dogs with mammary gland and mammary gland complex carcinomas MHC class I expression MHC class I expression in mammary gland carcinoma in mammary gland complex carcinoma Positive Negative P Positive Negative P n (%) n (%) Effect size n (%) n (%) Effect size Tumor size >3 cm 4 (80) 3 (75) 0.72 6 (50) 1 (100) 1 <3 cm 1 (20) 1 (25) 0.05 6 (50) 0 (0) 0.26 b2M expression Positive 3 (60) 0 (0) 0.12 11 (92) 1 (100) 1 Negative 2 (40) 4 (100) 0.63 1 (8) 0 (0) 0.08 Infiltration of lymphocytes Positive 3 (60) 0 (0) 0.12 10 (83) 0 (0) 0.23 Negative 2 (40) 4 (100) 0.63 2 (17) 1 (100) 0.53 Histological grade 1 1 (20) 0 (0) 0.09 6 (50) 1 (100) 1 2 3 (60) 0 (0) 0.8 4 (33) 0 (0) 0.26 3 1 (20) 4 (100) 2 (17) 0 (0) Event-free interval >24 months 5 (100) 0 (0) 0.008 12 (100) 1 (100) 1 <24 months 0 (0) 4 (100) 1 0 (0) 0 (0) - P was calculated using Fisher’s exact test with statistical significance set at P<0.05. An effect size of 0.5 was identified as a meaningful difference between groups. free interval (Table 1, P<0.05). effect size statistic was large (0.53), suggesting that loss of In the 13 dogs with mammary gland complex carcinomas, MHC class I expression was significantly associated with in- the histological grades was 1 in 7 dogs (54%), 2 in 4 dogs filtration of lymphocytes (Table 1). Of the 12 tumors positive (31%) and 3 in 2 dogs (15%). Immunohistochemical analy- for MHC class I expression, 6 (50%), 4 (33%) and 2 (17%) sis of the 13 mammary gland complex carcinomas showed were of histological grades 1, 2 and 3, respectively. The tu- that 12 (92.4%) were positive and 1 (7.6%) was negative for mor negative for MHC class I expression was of histological MHC class I expression. Regarding MHC class I expression, grade 1. Fisher’s exact test and the small effect size statistic immunoreactivity of luminal epithelial cells was observed (0.26) indicated no significant association between MHC in the membrane and cytoplasm. Immunoreactivity of myo- class I expression and histological grade (Table 1). Staining epithelial cells was the same as that of luminal epithelial intensity had no association with histological grade. All 12 cells. Of the 12 tumors positive for MHC class I expression, dogs with tumors positive for MHC class I expression and 6 (50%) each had tumors >3 cm and <3 cm in size, although the 1 dog with a tumor negative for MHC class I expression the tumor negative for MHC class I expression was >3 cm in survived without relapse for 2 years after surgical treat- size. Fisher’s exact test showed that the association between ment. Fisher’s exact test showed no significant association MHC class I expression and tumor size was not statistically between loss of MHC class I expression and the event-free significant (Table 1). Immunohistochemical analysis of the interval (Table 1). 12 tumors positive for MHC class I expression showed that Previously reported prognostic factors in dogs with mam- 11 (92%) were positive for b2M expression and 1 (8%) was mary gland tumors included tumor size, histological type, negative. Regarding b2M expression, immunoreactivity of evidence of metastasis at the time of diagnosis, clinical stage luminal epithelial cells was observed in the membrane and and histological grading using the Elston and Ellis grading cytoplasm. Immunoreactivity of myoepithelial cells was the method [3, 8, 17]. This study showed that loss of MHC class same as that of luminal epithelial cells. The tumor negative I expression from canine mammary gland carcinomas was for MHC class I expression was positive for b2M expression. associated with loss of b2M expression and prognosis. In Fisher’s exact test and the small effect size statistic (0.08) human cancers, abnormalities in MHC class I expression indicated that MHC class I expression and b2M expression can be caused by alterations in the MHC class I processing were not significantly associated (Table 1). Of the 12 tumors machinery, including TAP1, TAP2, tapasin, LMP2, LMP7 positive for MHC class I expression, 10 (83%) were positive, and b2M [2]. In human breast cancer, loss of MHC class and 2 (17%) were negative for infiltration of lymphocytes. I expression is caused by loss of b2M expression and/or The 1 dog with negative scores for MHC class I expression function [4]. Tumor cells that do not express MHC class I was negative for infiltration of lymphocytes. Fisher’s exact proteins on their surfaces can escape recognition by CD8 test revealed no significant association between MHC class T lymphocytes [18]. Thus, loss or downregulation of MHC I and infiltration of lymphocytes (Table 1). However, the class I expression has been associated with disease progres- MHC CLASS I AND PROGNOSIS IN CANINE MGT 1397 sion and/or poor clinical outcome [2]. Our study showed that REFERENCES positive expression of MHC class I and infiltration of lym- phocytes in canine mammary gland carcinoma and complex 1. Aptsiauri, N., Cabrera, T., Garcia-Lora, A., Lopez-Nevot, M. A., carcinoma were correlated. Moreover, infiltration by CD8 Ruiz-Cabello, F. and Garrido, F. 2007. MHC class I antigens and T-cells in canine mammary gland carcinoma has been found immune surveillance in transformed cells. Int. Rev. Cytol. 256: 139–189. [Medline] [CrossRef] to be a marker of good prognosis [5]. Therefore, in dogs with 2. Chang, C. C., Campoli, M. and Ferrone, S. 2003. HLA class mammary gland carcinoma, loss of MHC class I expression I defects in malignant lesions: what have we learned? Keio J. may correlate with poor prognosis. Loss of MHC class I Med. 52: 220–229. [Medline] [CrossRef] expression was observed in canine mammary gland carcino- 3. Chang, S. C., Chang, C. C., Chang, T. J. and Wong, M. L. 2005. mas of histological grade 3. Histological grading is related to Prognostic factors associated with survival two years after prognosis, being worse in dogs with grade 3 (poorly differ- surgery in dogs with malignant mammary tumors: 79 cases entiated) than in those with grade 1 (well differentiated) and (1998–2002). J. Am. Vet. Med. Assoc. 227: 1625–1629. [Med- 2 (moderately differentiated) mammary gland carcinomas line] [CrossRef] [8]. MHC class I expression may be lost in poorly differenti- 4. Chen, H. L., Gabrilovich, D., Virmani, A., Ratnani, I., Girgis, ated mammary gland carcinomas. Therefore, MHC class I K. R., Nadaf-Rahrov, S., Fernandez-Viña, M. and Carbone, D. P. 1996. Structural and functional analysis of β2 microglobulin expression loss may be correlated with poor prognosis. abnormalities in human lung and breast cancer. Int. J. Cancer In this study, dogs with mammary gland complex carci- 67: 756–763. [Medline] noma had a good prognosis. However, only 1 of these 13 5. Estrela-Lima, A., Araújo, M. S., Costa-Neto, J. M., Teixeira-Car- dogs showed loss of MHC class I expression. because of this valho, A., barrouin-Melo, S. M., Cardoso, S. V., Martins-Filho, imbalance, loss of MHC class I expression from these tumors O. A., Serakides, R. and Cassali, G. D. 2010. Immunophenotypic was not associated with loss of b2M expression, histological features of tumor infiltrating lymphocytes from mammary car - grade or prognosis. Tumors in 12 of the 13 dogs with mam- cinomas in female dogs associated with prognostic factors and mary gland complex carcinoma (12/13) showed expression survival rates. BMC Cancer 10: 256. [Medline] [CrossRef] of MHC class I, and all of these dogs had a good prognosis. 6. Gilbertson, S. R., Kurzman, I. D., Zachrau, R. E., Hurvitz, A. I. Thus, the prognosis of dogs with mammary gland tumors and black, M. M. 1983. Canine mammary epithelial neoplasms: biologic implications of morphologic characteristics assessed in is associated with both histological grade and tumor type. 232 dogs. Vet. Pathol. 20: 127–142. [Medline] Dogs with carcinomas had a poorer prognosis (death rate 7. Hsieh, C. H., Hsu, Y. J., Chang, C. C., Liu, H. C., Chuang, K. L., 67.3%) than dogs with complex carcinomas (death rate 0%) Chuang, C. K., Pang, S. T., Hasumi, K., Ferrone, S. and Liao, S. [8]. The low frequency of loss of MHC class I expression in K. 2009. Total HLA class I loss in a sarcomatoid renal carcinoma dogs with mammary gland complex carcinoma may be asso- cell line caused by the coexistence of distinct mutations in the ciated with the absence of relapse or prolonged survival after two encoding beta2-microglobulin genes. Cancer Immunol. Im- surgical treatment. This study had some limitations, includ- munother. 58: 395–408. [Medline] [CrossRef] ing the small study sample and the imbalanced data in dogs 8. Karayannopoulou, M., Kaldrymidou, E., Constantinidis, T. C. with mammary gland complex carcinoma. Further work is and Dessiris, A. 2005. Histological grading and prognosis in needed to evaluate the association between loss of MHC dogs with mammary carcinomas: application of a human grading method. J. Comp. Pathol. 133: 246–252. [Medline] [CrossRef] class I expression and loss of b2M expression, histological 9. Misdorp, W. and Hart, A. A. 1976. Prognostic factors in canine grade, infiltration of CD8 T lymphocytes and prognosis in a mammary cancer. J. Natl. Cancer Inst. 56: 779–786. [Medline] larger and better balanced population of dogs with mammary 10. Misdorp, W., Else, R. W., Hellmén, E. and Lipscomb, T. P. 1999. gland complex carcinomas. Histological classification of mammary tumors of the dog and Canine mammary gland tumors >3 cm in size have been the cat. pp. 11–29. In: Armed Forces Institute of Pathology associated with poor prognosis [17]. In this study, loss of and the American Registry of Pathology and the World Health MHC class I expression was not associated with tumor size Organization Collaborating Center for Worldwide Reference on in dogs with mammary gland and complex carcinomas. In Comparative Oncology, vol. 7, Washington, D.C. humans, loss of MHC class I expression from tumor cells 11. Misdorp, W., Cotchin, E., Hampe, J. F., Jabara, A. G. and Von occurs when the primary tumor penetrates the basal mem- Sandersleben, J. 1973. Canine malignant mammary tumors. 3. Special types of carcinomas, malignant mixed tumors. Vet. branes, invading surrounding tissues and/or starts to metas- Pathol. 10: 241–256. [Medline] [CrossRef] tasize to regional lymph nodes or distant organs [7]. None 12. Morrison, L. A., Lukacher, A. E., braciale, V. L., Fan, D. P. and of the dogs in our study showed any evidence of metastasis. braciale, T. J. 1986. Differences in antigen presentation to MHC Therefore, loss of MHC class I expression may be indepen- class I- and class II-restricted influenza virus-specific cytolytic T dent of tumor size. lymphocyte clones. J. Exp. Med. 163: 903–921. [CrossRef] This study is limited by the small sample size. In future 13. Moulton, J. E. 1990. Tumor of the mammary gland. pp. 518–552. studies, a larger number of mammary gland tumors should In: Tumors in Domestic Animals. 3rd ed. (Moulton, J. E. ed.), be evaluated with regard to loss of MHC class I expression Univ. California Press, berkeley. as an independent prognostic factor by multivariate analysis, 14. Nakajima, Y., Hoshi, F., Higuchi, S. and Kawamura, S. 1999. and the mechanism of MHC class I expression loss should The complete amino acid sequence of dog beta2-microglobulin. J. Vet. Med. Sci. 61: 517–521. [Medline] [CrossRef] also be explored. In conclusion, our findings suggested that 15. Nakajima, Y., Hoshi, F., Higuchi, S. and Kawamura, S. 2001. loss of MHC class I expression may be a factor associated Determination of canine beta2-microgloblin in plasma and urine with poor prognosis in dogs with mammary gland carcinoma. 1398 T. TANAKA ET AL. by enzyme-linked immunosorbent assay. J. Vet. Med. Sci. 63: E., Serrano, A. and Morell, M. 2003. Major histocompatibility 343–345. [Medline] [CrossRef] complex status in breast carcinogenesis and relationship to apop- 16. Pedersen, L. O., Hansen, A. S., Olsen, A. C., Gerwien, J., Nissen, tosis. Hum. Pathol. 34: 1283–1289. [Medline] [CrossRef] M. H. and buus, S. 1994. The interaction between beta 2-mi- 19. Saleh, F. and Abdeen, S. 2007. Pathobiological features of breast croglobulin (beta 2m) and purified class-I major histocompat- tumours in the State of Kuwait: a comprehensive analysis. J. ibility (MHC) antigen. Scand. J. Immunol. 39: 64–72. [Medline] Carcinog. 6: 12. [Medline] [CrossRef] [CrossRef] 20. Uva, P., Aurisicchio, L., Watters, J., Loboda, A., Kulkarni, A., 17. Philibert, J. C., Snyder, P. W., Glickman, N., Glickman, L. T., Castle, J., Palombo, F., Viti, V., Mesiti, G., Zappulli, V., Mar- Knapp, D. W. and Waters, D. J. 2003. Influence of host factors conato, L., Abramo, F., Ciliberto, G., Lahm, A., La Monica, on survival in dogs with malignant mammary gland tumors. J. N. and de Rinaldis, E. 2009. Comparative expression pathway Vet. Intern. Med. 17: 102–106. [Medline] [CrossRef] analysis of human and canine mammary tumors. BMC Genomics 18. Redondo, M., Garcia, J., Villar, E., Rodrigo, I., Perea-Milla, 10: 135. [Medline] [CrossRef]

Journal

Journal of Veterinary Medical SciencePubmed Central

Published: May 31, 2013

There are no references for this article.