WT1 Promotes Cell Proliferation In Non-small Cell Lung Cancer Cell Lines Through Up-regulating Cyclin D1 In Vitro And In Vivo

Objective: To investigate the expression of WT1(Wilms’ tumor gene 1) in NSCLC(non-small cell lung cancer) tissues and the corresponding para-cancerous tissues, and to explore the relationship between WT1 expression and the proliferation of NSCLC cells in vitro. Methods: The expression levels of WT1 in 79 NSCLC tissues and the corresponding para-cancerous tissues were detected by IHC(immunohistochemistry) and RT-PCR(real-time fluorescence quantitative-PCR). Recombination plasmids of p LV-GFP-WT1 and pLL3.7-WT1-shRNA were constructed and transfected into NSCLC cells(A549/H1299/H1650) by Lentivirus production. The expression level of WT1 protein in NSCLC cells after transfection with pLV-GFP-WT1 and p LL3.7-WT1-shRNA were detected by Western blotting, and the proliferation of NSCLC was detected in vitro and vivo. The cell-cycle of NSCLC cells was detected by flow cytometric analysis. Results: The expression level of WT1 in NSCLC tissues was higher than that in the corresponding para-cancerous tissues(P < 0.01). Recombination plasmids of p LV-GFP-WT1 and pLL3.7-WT1-shRNA were successfully constructed and transfected into NSCLC cells. After transfection, the expression level of WT1 protein was overexpressed by p LV-GFP-WT1 and knocked down by p LL3.7-WT1-shRNA. Overexpressing WT1 could enhance the proliferation of NSCLC while down-regulating WT1 would do the contrary. WT1 accelerates S-phase entry of cell cycle by up-regulating Cyclin D1 protein expression. Conclusion: The expression level of WT1 in NSCLC tissues is higher than that in the corresponding para-cancerous tissues. WT1 can promote the proliferation of NSCLC cells by up-regulating Cyclin D1 protein expression. It is suggested that WT1 may act as an oncogene in NSCLC.