Figure 5

Oxaliplatin-treated tumors exhibited changes consistent with epithelial-mesenchymal transition (EMT). Immunohistochemistry revealed typical membranous E-cadherin expression in the cell-cell contacts of untreated tumors. In contrast, oxaliplatin-treated tumors showed an overall reduction of E-cadherin expression, especially at the invasive front where the expression of E-cadherin was faint or even undetectable. Instead, N-cadherin was significantly upregulated in oxaliplatin-treated tumors. N-cadherin-positive tumor cells were concentrated in areas of tumor-stroma interaction and were scattered in the stroma. Increased expression of vimentin and Snail were also detected in the invasive front of oxaliplatin-treated tumors.