| Abstract:Objective:To investigate the relationships between the expressions of TGF-β1, E-cadherin and Vimentin in colorectal adenocarcinoma and the clinicopathological data, the effort of TGF-(31 induced epithelial mesenchymal transition in colon carcinoma cells HCT116 and the efforts of PI3K/Akt pathway during TGF-β1 induced epithelial mesenchymal transformation in colon carcinoma cells HCT116, the purpose of this study is providing a possible mechanism of the invasion and metastasis in colorectal adenocancinoma and a theoretical basis for clinical treatment of colorectal adenocarcinoma. Methods: 1.Expressions of TGF-β1, E-cadherin and Vimen-tin protein were detected in 52 cases of surgically resected colorectal adenocarcinoma specimens by the method of immunohistochemistry, which including colorectal adenocarcinoma tissues and its adjacent mucosa.2.colon carcinoma cells HCT116 cells were treated with TGF-β1, TGF-β1 combined LY294002, and those treated with PBS served as controls. (1) The morphological changes of colon carcinoma cells HCT116 were observed with inversphase microscope. (2) The changes of p-Akt protein of colon cancer cells HCT116 were observed by using immunocytochemistry. (3) The changes of E-cadherin and Vimentin of colon carcinoma cells HCT116 were observed by using RT-PCR and immunocyto-chemistry. Results:1.The positive rate of TGF-β1 protein expression was higher significantly in colorectal adenocarcinoma (73.08%) than that in its adjacent mucosa tissues (32.69%,P=0.00).2.The positive rate of E-cadherin protein expression was lower in colorectal adenocarcinoma (48.08%) than that in its adjacent mucosa tissues (76.92%, P=0.00), and the positive rate of Vimentin protein expression in colorectal adenocarcinoma (23.08%) was higher significantly than that in its adjacent mucosa tissues (0.00%, P=0.00). 3.There were negative correlation between the positive rate of TGF-β1 protein expression and that of E-cadherin protein expression in colorectal adenocarcinoma (Tb=-0.55, P=0.00), and positive correlation between the positive rate of TGF-β1 protein expression and that of Vimentin protein expression in colorectal adenocarcinoma (Tb=0.33, P=0.02), and negative correlation between the positive rate of E-cadherin protein expression and that of Vimentin protein expression in colorectal adenocarcinoma (Tb=-033, P=0.02).4.colon carcinoma cells HCT116 treated with PBS showed the paving stones shaped, and colon carcinoma cells HCT116 treated with TGF-β1 (lOng/ml) for 48 hours lost the original arrange, widened the cell gap, appeared the spindle change and increased cell heteromorphism.5. After treation with TGF-β1 (10ng/ml) for 48 hours, the result showed that the positive rate of E-cadherin protein expression (39.00%) was lower significantly than that in control group (57.10%, P<0.05), and the positive rate of Vimentin protein expression (52.80%) was higher significantly than that in control group (42.0%, P<0.05) by using immunocytochemistry. the results showed that expression of E-cadherin mRNA in TGF-β1 group (1.51±0.06) was obviosuly lower than that in control group (1.63±0.05, P<0.05), and expression of Vimentin mRNA in TGF-β1 group (3.04±0.11) was obviously higher than that in control group (1.66±0.09, P<0.05) by using RT-PCR.6.After treation with TGF-β1(10ng/ml) combined LY294002 for 48 hours, the result shows that the positive rate of E-cadherin protein expression (56.30%) was higher signficantly than that in TGF-β1 group (39.00%, P<0.05), and the positive rate of Vimentin protein expression (42.60%) was lower significantly than that in TGF-β1 group (52.80%, P<0.05) by using immunocytochemistry. the results showed that expression of E-cadherin mRNA in TGF-β1+LY294002 group (2.03±0.10) was obviously higher than that in TGF-β1 group (1.51±0.06,P<0.05), and expression of Vimentin mRNA in TGF-β1+LY294002 group (1.62±0.15) was obviously lower than that in TGF-(31 group (3.04±0.11, P<0.05) by using RT-PCR. Comclusions:1.There may be epithelial mesenchymal transition in which TGF-β1 may be involved and play an important role in carcinogenesis and development of colorectal adenocarcinoma.2.TGF-β1 can induce epithelial mesenchymal transition in colon carcinoma cells HCT116 throught a series of down stream signaling pathways.3.PI3K/Akt pathway may be an important part of the process that TGF-β1 induce epithelial mesenchymal transition in colon carcinoma cells HCT116, and specific blocking its path way can reverse TGF-β1 induced epithelial mesenchymal transition in colon carcinoma cells HCT116.4. Blocking PI3K/Akt signaling pathway may become the target for the drug treatment of colorectal adenocarcinoma, and provide a possible theoretical basis and a new way of thinking for the treatment of colorectal adenocarcinoma. |
