In parallel with these functional studies, we analyzed by RT-qPCR the expression level of genes involved in (i) epithelial functions, including antimicrobial defense (Reg3g, Il22, Ang4), differentiation (Lgr5, Math1, Hes1, Spdef, Alpi), and permeability (Cldn1, Occldn, Zo1), and (ii) in mucosal inflammation (Il1b, Tnfa, Il6) and immune balance (Rorc, Foxp3, Il17, Ifng, Tgfb, Ccl20) in different regions of the GI tract (jejunum, ileum, and proximal colon) 14 or 19 days after tumor implantation. Here, CLDN1 is linked to neoplasm.