Curcumin suppresses tumor growth of gemcitabine-resistant non-small cell lung cancer by regulating lncRNA-MEG3 and PTEN signaling.

Abstract

Lung cancer is one of the most aggressive malignancies and the efficacy of chemotherapy or concurrent chemoradiation is limited in clinical application. Curcumin has been reported to block cancer development by modulating multiple signaling pathways. However, whether curcumin can inhibit gemcitabine-resistant non-small cell lung cancer through regulation of lncRNA and the involved molecular mechanisms are rarely reported. MTT assay, clonogenic assay, apoptosis assay, qRT-PCR, Western blotting, immunohistochemistry, xenograft experiment were carried out in the present study. The results showed that curcumin suppressed gemcitabine-resistant non-small cell lung cancer cell proliferation and induced apoptosis. Curcumin upregulated the expression of lncRNA-MEG3 and PTEN, and MEG3 overexpression could increase the level of PTEN expression, while MEG3 knockdown decreased the level of PTEN expression in gemcitabine-resistant non-small cell lung cancer cells. Curcumin treatment failed to inhibit the proliferation and induce apoptosis in MEG3 knockdown or PTEN knockdown cells. These findings show the antitumor activity of curcumin for potential clinical application in gemcitabine-resistant non-small cell lung cancer treatment.