IMMUNOHISTOCHEMICAL STUDY OF CLAUDIN-17 EXPRESSION IN CANINE MAMMARY GLAND TUMORS

Abstract

Mammary tumors are an important health problem infemale dogs, which constitute the most<br><br>common neoplasm in this population.Tight junctions are the apical cell-cell adhesion that regulate<br><br>paracellularpermeability and are critical for epithelial cell polarity. Studies show thatclaudin family<br><br>of proteins is integral component of tight junction. Loss ofcell-cell adhesion is central to the cellular<br><br>transformation, invasion andacquisition of metastatic potential. In this study we purpose to<br><br>investigate theexpression of Claudin-17 in canine mammary tumors using<br><br>immunohistochemistry. 20 samples of canine mammary gland tumors included in this study,<br><br>whichhad been confirmed histopathologically. Mouse brain and canine normal mammarygland<br><br>tissues were used as positive and negative controls, respectively.Immunohistochemistry was done on<br><br>formalin-fixed, paraffin-embdded sampleswith Avidin-Biotin Complex method (ABC) in which<br><br>Horse Radish Peroxidase(HRP) and DAB used for developing positive signals. Images analyzed<br><br>by\\\\\\"Image J\\\\\\" software, v1.43 (U.S.National Institutesof Health,Bethesda, MD, U.S.A.)<br><br>Immunohistochemistry results revealed that 15 (75%) oftumor samples showed weak<br><br>immunoreactivity and 5 (25%) moderateimmunoreactivity for Claudin-17. These results indicate<br><br>that Claduin-17expression could decrease in canine mammary gland tumors in comparison tonormal<br><br>canine mammary tissue. To our knowledge this is the first studyregarding Claudin-17 expression in<br><br>canine mammary gland tumors.