Original Article p63 and E-cadherin Expression in Canine Oral Squamous Cell Carcinoma

The expression of p63 and E-cadherin was studied in 22 oral squamous cell carcinomas in the dog according to immunohisto-chemical techniques. The association between these markers and clinicopathologic parameters was assessed. All tumor cells stud-ied showed enhanced p63 expression. Regarding E-cadherin expression, 17 of 22 cases (77.3%) showed decreased immunoreactivity, and in 13 of 22 cases (59.1%), its expression was cytoplasmic. Neither p63 nor E-cadherin expression patterns were associated with tumor size, bone invasion, or lymph node metastasis. p63 score was related to proliferating cell nuclear antigen proliferative index (P .020). A statistically significant correlation between the expression patterns of these 2 markers was noted (P .026). Furthermore, they were related with tumor grade. An atypical p63 labeling and a cytoplasmic E-cadherin staining were statistically related with a higher tumor grade (P .022 and P .017, respectively). These findings suggest that changes in p63 and E-cadherin expression are frequent events in oral squamous cell carcinoma in dogs. Keywords p63, E-cadherin, oral squamous cell carcinoma, dog Squamous cell carcinoma (SCC) is the second-most frequent oral cancer in dogs23 and one of the most common head and neck neoplasias in humans.2,42 In spite of its low metastati