miR-143/145 Cluster Regulate Multi-drug Resistance of Small Cell Lung Cancer

Objective  To explore the role of miR-143/145 cluster in regulating multi-drug resistance of small cell lung cancer(SCLC).

Methods We firstly detected the differential expression of miR-143/145 cluster in both the drug-sensitive cell line H69 and drug-resistant cell line H69AR by real-time PCR (RT-PCR). Then we transfected the cells with mimics or antagomir to increase or decrease the expression of miR-143/145 cluster. Then the sensitivities of the cells to chemotherapy drugs such as ADM, DDP, VP-16 were detected by CCK8 assay. The apoptosis rate and cell cycle were determined by flow cytometry.

Results The expression of miR-143/145 cluster was significantly higher in H69AR cells than that in H69 cells. miR-143/145 mimics could increase the expression of miR-143/145 and G2/M phase arrest, reduce cell apoptosis, and increase the expression of anti apoptotic BCL2, causing chemotherapeutic drug resistance of H69 cells; while the effect of miR-143/145 antagomir was contrary.

Conclusion miR-143/145 cluster may be associated with chemotherapy resistance of small cell lung cancer by reducing cells apoptosis.