[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.
Methods: 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 (P<0.01) in close correlation to the degree of tumor differentiation (P<0.05). Higher Tiam1 expression was detected in CRC with lymphatic metastasis than in primary CRC (P<0.05). The expressions of E-cadherin and CK in CRC tissues were significantly lowered in comparison with those in normal colorectal epithelium (P<0.01), showing a correlation to tumor differentiation (P<0.01) but not to lymphatic metastasis. Vimentin was significantly overexpressed in CRC (P<0.01) and correlated to tumor differentiation (P<0.01) 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.