Delicaflavone reverses cisplatin resistance via endoplasmic reticulum stress signaling pathway in non-small cell lung cancer cells

Abstract

Background: The incidence and mortality of lung cancer continue to increase around the world; in 2018, new lung cancer cases accounted for 11.6% of all cancer cases, and lung cancer deaths accounted for 18.4% of cancer deaths. Cisplatin (DDP) is a first-line chemotherapy drug for lung cancer; however, DDP resistance can lead to a poor prognosis in patients with lung cancer. Therefore, reversing DDP resistance is a treatment goal. Materials and Methods: Cell counting kit-8 (CCK8) assays, wound healing analyses, Transwell assays, in vitro tumor xenografts, and flow cytometry were used to detect the proliferation, migration, invasion, and apoptosis of multidrug resistant A549/DDP and PC9/ DDP cells, respectively. Western blot was performed to detect protein levels of cleaved caspase-3, CHOP, and GRP78. Results: Delicaflavone inhibited DDP resistance of lung cancer cells and decreased proliferation in a dose-and time-dependent manner. It also decreased migration and invasion and enhanced apoptosis. Western blots showed that delicaflavone overcame DDP resistance by increasing the expression of GRP78 and CHOP and the apoptosis-related protein cleaved caspase-3. Conclusion: Delicaflavone can reverse DDP resistance in A549/DDP and PC9/DDP cells by inhibiting cell proliferation and migration and enhancing apoptosis and cleaved caspase-3 levels by increasing the expression of CHOP and GRP78 protein via the endoplasmic reticular stress pathway. It could be a useful therapeutic adjunct to treat DDP-resistant lung cancer.