Comparative E-cadherin and syndecan-1 protein expression in human and canine oral squamous cell carcinoma.

Oral squamous cell carcinoma (OSCC) is a prevalent form of oral cancer in humans and dogs. The altered expression of cell adhesion molecules, including E-cadherin (CDH1) and syndecan-1 (SDC1), is involved in cancer progression. This study aimed to investigate the protein expression of CDH1 and SDC1 in early and late clinical stages of human and canine OSCC (hOSCC and cOSCC, respectively), using immunohistochemistry. Formalin-fixed and paraffin embedded tissue blocks were obtained from 21 hOSCC, 8 human normal gingiva, 26 cOSCC, and 13 canine normal gingiva. Clinical stages and histological subtypes of samples were evaluated. The results indicated that both human and canine OSCC exhibited reduced levels of CDH1 and SDC1 expression at the cell membrane regardless of clinical stage or histological subtype. Additionally, decreased levels of total SDC1 expression were observed in hOSCC compared with normal controls. In conclusion, this study demonstrates a similarity in the immunohistochemical expression of CDH1 and SDC1 between humans and dogs with OSCC, lending support to the potential use of dogs as a model for studying human head and neck squamous cell carcinoma.