Atractylenolide I Enhances Cisplatin Sensitivity in Renal Cell Carcinoma through Activation of FOXO1/ATG5 Pathway-Regulated Autophagy Hyperactivation

Abstract

Background: A previous study found that Kidney and Spleen Supplement Formula could induce apoptosis in renal cell cancer cells by enhancing autophagy. Atractylenolide I (AT-I), as one of the main active ingredients of Kidney and Spleen Supplement Formula, is believed to have anticancer and chemotherapy-enhancing effects. We mainly focused on the role and mechanism of AT-I in cisplatin chemotherapy of renal cell carcinoma. Methods: Renal cell carcinoma cells were treated with different concentrations of AT-I or cisplatin, and the effects of cell viability and proliferation were determined using Cell Counting Kit-8 and 5-ethynyl-2′-deoxyuridine (EdU) staining assays. Forkhead box-1 (FOXO1) mRNA levels were detected using quantitative real-time polymerase chain reaction, and autophagy-associated proteins were determined using Western bolt. Results: AT-I concentration-dependently decreased cell viability and proliferation and enhanced the inhibitory effect of cisplatin on cell growth in renal cell carcinoma cells (p < 0.05). AT-I upregulated light chain 3 (LC3) II/LC3 I, Beclin 1, FOXO1, and autophagy-related gene 5 (ATG5) expression and decreased P62 protein levels (p < 0.05). Overexpression of FOXO1 enhanced the inhibitory effect of cisplatin on cell viability and proliferation, while FOXO1 silencing reversed the chemosensitizing effect of AT-I (p < 0.05). Moreover, AT-I promotion of ATG5, Beclin 1, LC3 II/LC3 I, and attenuation of P62 were also partially subverted by FOXO1 silencing (p < 0.01). Conclusion: AT-I enhances cisplatin sensitivity in renal cell carcinoma cells through activation of FOXO1-ATG5 pathway-mediated excessive autophagy.