[Correlation between T lymphoma invasion and metastasis 1 expression and epithelial-mesenchymal transition in human colorectal carcinomas].

Objective To investigate the relationship between T lymphoma invasion and metastasis 1 (Tiam1) and epithelial-mesenchymal transition (EMT) in human colorectal carcinomas. Method Tiam1, E-cadherin, CK, and vimentin expressions in normal colorectal epithelium, colorectal carcinomas (CRC) and CRC with lymphatic metastasis were determined by immunohistochemistry using a two-step method. Results Tiam1 expression was significantly higher in CRC than in normal colorectal epithelium (P0.01) in close correlation to the degree of tumor differentiation (P0.05). Higher Tiam1 expression was detected in CRC with lymphatic metastasis than in primary CRC (P0.05). The expressions of E-cadherin and CK in CRC tissues were significantly lowered in comparison with those in normal colorectal epithelium (P0.01), showing a correlation to tumor differentiation (P0.01) but not to lymphatic metastasis. Vimentin was significantly overexpressed in CRC (P0.01) and correlated to tumor differentiation (P0.01) but not to lymphatic metastasis. Tiam1 expression was inversely correlated to E-cadherin and CK, but positively to vimentin. Conclusion Tiam1 is related to the metastasis of colorectal carcinoma, and may induce EMT to promote CRC metastasis.