Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong, China.
Department of Liver Surgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China.
Nat Commun. 2018 Dec 6;9(1):5214. doi: 10.1038/s41467-018-07402-8.
Obesity increases the risk of hepatocellular carcinoma (HCC) especially in men, but the molecular mechanism remains obscure. Here, we show that an androgen receptor (AR)-driven oncogene, cell cycle-related kinase (CCRK), collaborates with obesity-induced pro-inflammatory signaling to promote non-alcoholic steatohepatitis (NASH)-related hepatocarcinogenesis. Lentivirus-mediated Ccrk ablation in liver of male mice fed with high-fat high-carbohydrate diet abrogates not only obesity-associated lipid accumulation, glucose intolerance and insulin resistance, but also HCC development. Mechanistically, CCRK fuels a feedforward loop by inducing STAT3-AR promoter co-occupancy and transcriptional up-regulation, which in turn activates mTORC1/4E-BP1/S6K/SREBP1 cascades via GSK3β phosphorylation. Moreover, hepatic CCRK induction in transgenic mice stimulates mTORC1-dependent Gcsf expression to enhance polymorphonuclear myeloid-derived suppressor cell recruitment and tumorigenicity. Finally, the STAT3-AR-CCRK-mTORC1 pathway components are concordantly over-expressed in human NASH-associated HCCs. These findings unveil the dual roles of an inflammatory-CCRK circuitry in driving metabolic and immunosuppressive reprogramming through mTORC1 activation, thereby establishing a pro-tumorigenic microenvironment for HCC development.
肥胖增加了肝细胞癌(HCC)的风险,尤其是在男性中,但分子机制尚不清楚。在这里,我们表明雄激素受体(AR)驱动的癌基因细胞周期相关激酶(CCRK)与肥胖引起的促炎信号协同作用,促进非酒精性脂肪性肝炎(NASH)相关的肝癌发生。用高脂肪高碳水化合物饮食喂养的雄性小鼠肝脏中通过慢病毒介导的 Ccrk 基因敲除不仅消除了与肥胖相关的脂质积累、葡萄糖不耐受和胰岛素抵抗,还消除了 HCC 的发展。在机制上,CCRK 通过诱导 STAT3-AR 启动子共占据和转录上调来提供正反馈回路,这反过来又通过 GSK3β 磷酸化激活 mTORC1/4E-BP1/S6K/SREBP1 级联反应。此外,转基因小鼠肝脏中 CCRK 的诱导刺激 mTORC1 依赖性 Gcsf 表达,以增强多形核髓样来源的抑制性细胞的募集和致瘤性。最后,在人类 NASH 相关 HCC 中共同过度表达了 STAT3-AR-CCRK-mTORC1 通路成分。这些发现揭示了炎症-CCRK 通路在通过 mTORC1 激活驱动代谢和免疫抑制重编程中的双重作用,从而为 HCC 的发展建立了促肿瘤微环境。