Hydroxychloroquine suppresses lung tumorigenesis via inducing FoxO3a nuclear translocation through STAT3 inactivation

• Published in: Life sciences (1973) 2020-04, Vol.246, p.117366-13, Article 117366
• Main Authors: Lyu, Xin, Zeng, Lizhong, Zhang, Hua, Ke, Yue, Liu, Xuan, Zhao, Nannan, Yuan, Jingyan, Chen, Guoan, Yang, Shuanying
• Format: Article
• Language: English
• Subjects: A549 Cells; Ablation; Active Transport, Cell Nucleus - drug effects; Adenocarcinoma; Adenocarcinoma - drug therapy; Adenocarcinoma - metabolism; Animals; Anticancer properties; Antineoplastic Agents - therapeutic use; Antitumor activity; Apoptosis; Apoptosis - drug effects; Biocompatibility; Bioinformatic analysis; Cancer; Cell cycle; Cell Cycle - drug effects; Cell Line, Tumor; Cyclin-dependent kinase 2; Cyclin-dependent kinase 4; Cyclin-dependent kinase inhibitor p27; Cytotoxicity; Deactivation; Female; Forkhead Box Protein O3 - metabolism; Forkhead protein; FOXO3 protein; FoxO3a; Gene expression; Gene Expression Regulation, Neoplastic - drug effects; Humans; Hydroxychloroquine; Hydroxychloroquine - therapeutic use; Immunoblotting; Immunohistochemistry; In vivo methods and tests; Inactivation; Kinases; Localization; Lung adenocarcinoma; Lung Neoplasms - drug therapy; Lung Neoplasms - metabolism; Lungs; Mice, Nude; Molecular modelling; Neoplasm Transplantation; Nuclear transport; p27Kip1; Phosphorylation; Signal transduction; siRNA; STAT3; Stat3 protein; STAT3 Transcription Factor - metabolism; Toxicity; Translocation; Tumorigenesis
• ISSN: 0024-3205; 1879-0631
• DOI: 10.1016/j.lfs.2020.117366

Hydroxychloroquine exhibits synergistic anticancer properties as an adjuvant. However, the role and molecular mechanisms underlying of HCQ as monotherapy for lung adenocarcinoma (LUAD) have yet to be elucidated. We assessed the antitumor effects of HCQ in LUAD cells through a series of in vitro and in vivo assays. GEO database and R packages were used to predict molecular mechanisms of HCQ in the treatment of lung adenocarcinoma, followed by verification of gene expression and subcellular localization via immunoblotting, immunofluorescent and immunohistochemistry assays. We showed the phenotypic effects that HCQ inhibited cell growth, induced apoptosis and cell cycle arrest at G1/S transition in A549 and PC-9 cells, which was associated with inhibition of CDK2, CDK4, CyclinD1 and CyclinE, but up-regulation of p21 and p27Kip1. Bioinformatic analysis predicted that 63 targets related to HCQ and LUAD were mainly enriched in JAK-STAT and FoxO pathways. Then, we observed that HCQ decreased the phosphorylation of STAT3, but increased the expression of FoxO3a and its accumulation in the nucleus. The specific STAT3 inhibitor cryptotanshinon augmented the HCQ-induced upregulation and nuclear translocation of FoxO3a. In addition, HCQ increased the expression of p27Kip1, which was impaired by FoxO3a blockade with siRNA. Finally, ablation of p27Kip1 expression abrogated the cytotoxicity of HCQ. More importantly, similar results were further confirmed in vivo. Taken together, this study suggests that STAT3/FoxO3a/p27Kip1 signaling pathway is involved in the anticancer effects of HCQ, and provides preliminary evidence for therapeutic prospects of HCQ alone in LUAD. [Display omitted] •HCQ inhibits cell proliferation and induces cell cycle arrest at G1/S transition in LUAD.•JAK-STAT and FoxO3a pathways are related to HCQ and LUAD by bioinformatic analysis.•HCQ impairs lung tumorigenesis dependent of STAT3/FoxO3a/p27Kip1 signaling.•HCQ alone for LUAD exhibits anticancer activity in vivo without obvious toxicity.