Objective: To investigate the expression of B cell lymphoma-2 (Bcl-2) in lung cancer cells and the effect of the miR-1/Bcl-2 axis on the chemosensitivity of lung cancer. Materials and Methods: Real-time quantitative PCR and western blotting were used to detect the expression of Bcl-2 in human embryonic lung fibroblasts and lung cancer cells. The effects of siRNA directed against Bcl-2, in lung cancer tissue samples was detected by immunohistochemistry; these results were used to develop prognostic models. Bioinformatic analyses, dual luciferase reporter gene technology, and western blotting technology were used to explore the targeted regulation of miR-1 on bcl-2. The effect of miR-1 on the chemosensitivity of lung cancer cells was measured using the MTT assay. Results: Compared with human embryonic lung fibroblasts, Bcl-2 was highly expressed in the lung cancer cells, especially in H460 cells. After silencing Bcl-2 with siRNA, the sensitivity of the cells to cisplatin (CDDP) increased. Immunohistochemical results and prognostic analysis revealed that high Bcl-2 expression in lung cancer tissues was negatively correlated with prognosis of lung cancer patients; A dual luciferase reporter assay combined with western blotting confirmed that miR-1 can bind to the Bcl-23' UTR region and regulate its expression. Overexpression of miR-1 in lung cancer cells (H460 and A549) increased the sensitivity of these cells to CDDP. Conclusion: Bcl-2 is upregulated in lung cancer cells, which is negatively correlated with the patient prognosis. miR-1 affects the chemosensitivity of lung cancer cells by targeting Bcl-2. These data should provide a theoretical basis for refining the molecular mechanisms of chemoresistance in lung cancer.
Keywords: Bcl-2; chemosensitivity; lung cancer; miR-1; prognosis.