癌症干细胞
同源盒蛋白纳米
癌变
癌症研究
生物
干细胞
脱氮酶
癌细胞
流式细胞术
基因敲除
细胞生物学
化学
分子生物学
癌症
泛素
细胞凋亡
诱导多能干细胞
胚胎干细胞
生物化学
遗传学
基因
作者
Juhong Wang,Fei Shao,Yannan Yang,Wei Wang,Xueying Yang,Renda Li,Hong Cheng,Sijin Sun,Xiaoli Feng,Yibo Gao,Jie He,Zhimin Lu
摘要
Maintenance of cancer stem-like cell (CSC) stemness supported by aberrantly regulated cancer cell metabolism is critical for CSC self-renewal and tumor progression. As a key glycolytic enzyme, hexokinase 2 (HK2) plays an instrumental role in aerobic glycolysis and tumor progression. However, whether HK2 directly contribute to CSC stemness maintenance in small cell lung cancer (SCLC) is largely unclear. In this study, we aimed to investgate whether HK2 independent of its glycolytic activity is directly involved in stemness maintenance of CSC in SCLC.Immunoblotting analyses were conducted to determine the expression of HK2 in SCLC CSCs and their differentiated counterparts. CSC-like properties and tumorigenesis of SCLC cells with or without HK2 depletion or overexpression were examined by sphere formation assay and xenograft mouse model. Immunoprecipitation and mass spectrometry analyses were performed to identify the binding proteins of CD133. The expression levels of CD133-associated and CSC-relevant proteins were evaluated by immunoblotting, immunoprecipitation, immunofluorescence, and immunohistochemistry assay. RNA expression levels of Nanog, POU5F1, Lin28, HK2, Prominin-1 were analyzed through quantitative reverse transcription PCR. Polyubiquitination of CD133 was examined by in vitro or in vivo ubiquitination assay. CD133+ cells were sorted by flow cytometry using an anti-CD133 antibody.We demonstrated that HK2 expression was much higher in CSCs of SCLC than in their differentiated counterparts. HK2 depletion inhibited CSC stemness and promoted CSC differentiation. Mechanistically, non-mitochondrial HK2 directly interacted with CD133 and enhanced CD133 expression without affecting CD133 mRNA levels. The interaction of HK2 and CD133 promoted the binding of the deubiquitinase ubiquitin-specific protease 11 (USP11) to CD133, thereby inhibiting CD133 polyubiquitylation and degradation. HK2-mediated upregulation of CD133 expression enhanced the expression of cell renewal regulators, SCLC cell stemness, and tumor growth in mice. In addition, HK2 expression was positively correlated with CD133 expression in human SCLC specimens, and their expression levels were associated with poor prognosis of SCLC patients.These results revealed a critical non-metabolic function of HK2 in promotion of cancer cell stemness. Our findings provided new insights into the multifaceted roles of HK2 in tumor development.
科研通智能强力驱动
Strongly Powered by AbleSci AI