ABSTRACT
@#[Abstract] Objective: To investigate the effect of RG108 on the proliferation and apoptosis of human non-small cell lung cancer (NSCLC) cell lines (A549, H1299) and explore its molecular mechanism. Methods: A549 and H1299 cells were cultured in vitro and treated with different concentrations of RG108. The cell proliferation, cell cycle and apoptosis were detected by MTT assay and Flow cytometry, respectively. qPCR and Western blotting (WB) were used to detect the TFPI-2 mRNA and protein expressions as well as the expression of TMPRSS4 in cells. Meanwhile, the methylation status and degree of TFPI-2 promoter in cells were detected with Methylation-specific PCR (MSP) and colorimetry. Finally, siRNA-TFPI-2 and pcDNA3.0-TMPRSS4 plasmids were used to silence TFPI-2 or overexpress TMPRSS4, and then the changes in cell proliferation and apoptosis were detected. Results: After treatment with RG108, the proliferation rate of A549 and H1299 cells were significantly decreased (all P<0.05), while the apoptosis rate were significantly increased(P<0.05), the cell cycle were arrested in G1/S phase (P<0.05), and the intracellular mRNA and protein expressions of TFPI-2 were significantly increased (P<0.01 or P<0.05). Meanwhile, the methylase degree in TFPI-2 promoter region and the expression of TMPRSS4 in cells were all significanly decreased ( all P<0.05). After TFPI-2 silence, the proliferation levels of A549 and H1299 cells were significantly increased(all P<0.05); however, the apoptosis rate of A549 and H1299 cells were significantly reduced after transfection with pcDNA3.0-TMPRSS4(all P<0.05). Conclusion: RG108 can inhibit proliferation of A549 and H1299 cells and promote apoptosis by inhibiting the methylation of TFPI-2 and negatively regulates the expression of TMPRSS4.