MicroRNA-185-5p modulates chemosensitivity of human non-small cell lung cancer to cisplatin via targeting ABCC1.

OBJECTIVE: MicroRNA-185-5p (miR-185-5p) dysregulation is found in various human cancers. Our purpose is to investigate the association of miR-185-5p expression with the sensitivity of non-small cell lung cancer (NSCLC) to cisplatin.

MATERIALS AND METHODS: Real-time PCR or Western blot assay was performed to detect the expression of mature miR-185-5p and ATP-binding cassette, subfamily C, member 1 (ABCC1) protein. Cell lines with abnormal expression of miR-185-5p were generated using miR-185-5p inhibitor and mimics. The viabilities of treated cells were analyzed using MTT assay. Cell apoptosis was evaluated by TUNEL assay. Apoptosis-related protein expressions were tested by Western blot. Dual-luciferase assay was applied to assess the target gene of miRNA.

RESULTS: The expression level of miR-185-5p in A549 cell line was significantly higher than that in A549/DDP cell line (p < 0.05). Transfection of miR-185-5p mimics increased the sensitivity of A549 cells to cisplatin and the expression of an apoptosis-related factor, and restrained cell proliferation. MiR-185-5p inhibitor promoted cisplatin resistance and cell growth in A549 cells, and declined apoptosis-related factor levels. ABCC1 was verified as the target gene of miR-185-5p. MiR-185-5p exhibited negative correlation with ABCC1 in A549/DDP cells.

CONCLUSIONS: The results of the present study demonstrated that inhibition of miR-185-5p was involved in chemo-resistance of NSCLC cells to cisplatin via down-regulating ABCC1.