The Influence Of Bmi-1on The Epithelial-mesenchymal Transition In Non-small Cell Lung Cancer

Objective To detecte the expression of Bmi-1mRNA and protein, E-Cadherin and Vimentin protein in non-small cell lung cancer tissues and adjacent normal tissues,to explore the relationship between Bmi-1and the epithelial-mesenchymal transition in non-small cell lung cancer and clinicopathological characteristics, and to provide the theoretical foundation for decreasing of the NSCLC metastasis and the discovery of new biological therapeutic targets.Methods①The expression of Bmi-1, E-Cadherin and Vimentin proteins were detected in50cases of NSCLC tissues and30cases of adjacent tissues by PV-9000immunohistochemical method.②The expression of Bmi-1mRNA was detected in30cases of NSCLC tissues and18cases of adjacent tissues by RT-PCR method.Results①Results of Immunohistochemistry:The expression of Bmi-1and Vimentin protein in the NSCLC tissues was higher than that in the adjacent tissues (P<0.05) while the expression of E-Cadherin protein was obviously lower than that in the adjacent tissues(P<0.05). The expressive intensity of Bmi-1, E-Cadherin and Vimentin protein between the two kind tissues had statistic significance (Z=-4.092、-4.413、-2.965,P<0.05)。The expression of Bmi-1protein related to the lymph node metastasis and TNM staging (P<0.05), and had no relation to the patients’ gender, age, tumor size, differentiation and tumor types (P>0.05). Both the expression of E-Cadherin and Vimentin protein were related to the tumor differentiation, TNM staging and the lymph node metastasis (P<0.05), but unrelated to the patients’ gender, age, tumor size and types (P>0.05). Moreover, according to the results of correlation analysis, there was a negative correlation between the expression of the Bmi-1and E-Cadherin protein in the50cases of NSCLC tissues (r=-0.416, P<0.05), and a positive correlation between the Bmi-1and Vimentin protein (r=0.356, P<0.05).②Result of RT-PCR:The positive rate of the Bmi-1mRNA expression was higher in NSCLC tissues than the adjacent tissues.(P<0.01), and the correlation analysis showed that the positive rate of the Bmi-1mRNA was positively correlated with the Bmi-1protein in the NSCLC tissues (P<0.05)Conclusions:①The expression of E-Cadherin protein is downregulated and the expression of Vimentin protein is upregulated in the NSCLC tissues, which may suggest that the epithelia-mesenchymal transition happens.②The expression of Bmi-1protein in the NSCLC tissues increases with both TMN staging and lymph node metastasis may show that Bmi-1protein may be correlated with the tumor progress and metastasis. ③In the NSCLC tissues, the expression of Bmi-1protein is negatively correlated with the E-Cadherin protein but positively correlated with the Vimentin protein. It may suggest that the Bmi-1protein promotes the epithelial-mesenchymal transition in the NSCLC, and then promotes the tumor invasion and metastasis.④Positive correlation is found between the positive rate of Bmi-1gene and protein in the NSCLC, which may show that Bmi-lmay influence the EMT at the gene level.