肝癌是世界范围内常见的恶性肿瘤之一,在我国每年大约有25万人死于肝癌,位居恶性肿瘤死亡率的第二位,是严重威胁人们健康乃至生命的恶性疾病。目前对肝癌的治疗主要有手术、放疗、化疗及生物治疗等,总体治疗效果不佳。其中,肝细胞癌(hepatocellutar carcinoma,HCC)是最为常见的肝脏原发性恶性病变,其死亡率呈逐渐增长趋势。HCC每年造成全球约100万患者死亡,属癌症中的第三杀手,引起全球学者的广泛关注。
门静脉癌栓(pVTT)是肝细胞癌的主要并发症,并与较差生存期相关。已知长链非编码RNA(lncRNA)有助于HCC的转移,但是,lncRNAs是否以及如何影响pVTT的发展,仍不明确。
近期,来自上海第二军医大学的研究人员,在国际知名学术期刊《Clinical Cancer Research》发表题为“ICAM-1-related non-coding RNA in cancer stem cells maintains ICAM-1 expression in Hepatocellular Carcinoma”的学术成果。这项研究确定了一个新的lncRNA——ICR,可特异性地调节ICAM-1 +肝癌细胞的肿瘤干细胞特性,并有助于门静脉癌栓的发展。因此,ICR可能是肝癌治疗的一个有用的新靶点。延伸阅读:中国学者解析肝癌中的lncRNA。
本文通讯作者是第二军医大学长海医院临床实验中心主任、博士生导师刘善荣教授,其曾在美国伊利诺伊大学从事博士后研究,先兼任长海医院转化医学中心细胞发育与重编程实验室主任。2007年入选“上海市浦江人才A类支持计划”; 2009年遴选为上海市“东方学者”特聘教授; 2010年入选国家教育部“跨世纪优秀人才支持计划”。长期从事肿瘤转移与非编码RNA相关的研究,研究成果多次发表在Gastroenterol、Hepatology、Cancer Res、Chin J Cancer、J Hepatol等著名学术期刊。
在目前的这项研究中,研究人员在HCC的ICAM-1+肿瘤干细胞(CSCs)中确定了一个新的高度表达的lncRNA(ICAM-1-related,ICR)。这个lncRNA调节着CSC的性能,并有助于pVTT的发展。
Magna Nuclear RIp™Kit — 非编码RNA(lncRNA、enhancer RNA 、miRNA等)与蛋白相互作用创新技术
研究人员使用基因芯片和生物信息学分析,来鉴定差异表达的lncRNA。用实时pCR和蛋白印迹法来检测细胞系和肿瘤中的基因表达。研究人员进行了Sphere formation实验,以在体外调查肿瘤细胞的干细胞特性。研究人员开展了回顾性和前瞻性研究,来探讨ICR表达与临床预后之间的关系。
结果表明,与相应的原发性肿瘤相比,pVTT表达不同lncRNAs和mRNA,包括上调的lncRNA ICR和ICAM-1。ICR可调节ICAM-1的表达——通过增加它在RNA双链形成时的mRNA稳定性,从而调节ICAM-1 +肝癌细胞的CSC特性。ICAM-1 +肝癌细胞中的ICR转录,是由Nanog调控的,ICR的原位抑制,可在体内显著降低ICAM-1表达及肿瘤中的ICAM-1 +肝癌细胞。
此外,肿瘤中升高的ICR和ICAM-1表达,与pVTT的发展和不良的临床疗效相关。总而言之,这项研究表明,ICR可特异性地调节ICAM-1 +肝癌细胞的CSC特性,并有助于门静脉癌栓的发展。因此,ICR可能是肝癌治疗的一个有用的新靶点。
(生物通:王英)
生物通推荐原文摘要:
ICAM-1-related non-coding RNA in cancer stem cells maintains ICAM-1 expression in Hepatocellular Carcinoma
Abstract
purpose:portal vein tumor thrombus (pVTT) is a major complication of hepatocellular carcinoma (HCC) and is associated with poor survival. Long non-coding RNAs (lncRNAs) contribute to HCC metastasis, but whether and how lncRNAs affects pVTT development remains unclear. In the present study, a novel highly expressed lncRNA (ICAM-1-related, ICR) was identified in ICAM-1+ cancer stem cells (CSCs) in HCC. This lncRNA regulated CSC properties and contributed to pVTT development. Experimental Design:We used microarray and bioinformatics analyses to identify differentially expressed lncRNAs. Real-time pCR and western blotting were used to assess gene expression in cell lines and tumors. Sphere formation assays were performed to investigate stem cell properties of tumor cells in vitro. Retrospective and prospective studies were employed to investigate the relationship between ICR expression and clinical outcomes. Results:Compared with the corresponding primary tumors, pVTT expressed different lncRNAs and mRNAs, including the up-regulated lncRNA ICR and ICAM-1. ICR regulated ICAM-1 expression by increasing the stability of its mRNA through RNA duplex formation, which modulated the CSC properties of ICAM-1+ HCC cells. ICR transcription in ICAM-1+ HCC cells was regulated by Nanog and inhibition of ICR in situ significantly reduced ICAM-1 expression and ICAM-1+ HCC cells in tumors in vivo. Moreover, elevated ICR and ICAM-1 expression in tumors was correlated with pVTT development and poor clinical outcomes. Conclusions:Our study demonstrates that ICR specifically regulates CSC properties of ICAM-1+ HCC cells and that ICR contributes to pVTT development. Therefore, ICR may be a promising target for HCC therapy.