Second Department of Hepatobiliary Surgery, Zhujiang Hospital, State Key Laboratory of Organ Failure Research, Co-Innovation Center for Organ Failure Research, Southern Medical University, Guangzhou, China.
Department of Geriatrics, The Affiliated Hospital of Qingdao University, Qingdao, China.
Int J Biol Sci. 2019 Jun 4;15(8):1664-1675. doi: 10.7150/ijbs.35216. eCollection 2019.
Liver CSCs are a rare subpopulation of heterogenous liver cancer cells with self-renewal and differentiation properties, which has emerged as a promising therapeutic target. Compelling data shows that NK cells selectively eliminate human cancer derived CSCs like colorectal carcinoma, melanoma, and glioblastoma. But the effect of NK cells on liver CSCs still remains unknown. To study the cytotoxic effect of NK cells on liver CSCs and the mechanism, we performed cytotoxicity assay, ELISA assays, CRISPRi, qRT-PCR, immunoblotting, RNA immunoprecipitation, and luciferase reporter using two types of CSCs reprogrammed from HCC. CSCs derived from liver cancer were susceptible to NK cell mediated cytotoxicity. The susceptibility of liver CSCs to NK cell-mediated cytotoxicity declined significantly after silencing CD44 by CRISPRi-mediated gene knockdown. CD44 3' UTR functioned as a ceRNA to regulate the expression of ULBP2 mainly by competing miR-34a. CD44 3' UTR functioned as a ceRNA to enhance NK sensitivity of liver cancer stem cell by regulating ULBP2 expression.
肝肿瘤干细胞（Liver CSCs）是一种具有自我更新和分化特性的稀有异质性肝癌细胞亚群，已成为有前途的治疗靶点。有强有力的数据表明，NK 细胞选择性地消除了源自结直肠癌、黑色素瘤和神经胶质瘤等人类癌症的 CSCs。但 NK 细胞对肝 CSCs 的影响仍不清楚。为了研究 NK 细胞对肝 CSCs 的细胞毒性作用及其机制，我们使用两种从 HCC 重编程的 CSCs 进行了细胞毒性测定、ELISA 检测、CRISPRi、qRT-PCR、免疫印迹、RNA 免疫沉淀和荧光素酶报告检测。来源于肝癌的 CSCs 易受 NK 细胞介导的细胞毒性作用影响。经 CRISPRi 介导的基因敲低沉默 CD44 后，肝 CSCs 对 NK 细胞介导的细胞毒性的敏感性显著下降。CD44 的 3'UTR 作为 ceRNA，主要通过竞争 miR-34a 来调节 ULBP2 的表达。CD44 的 3'UTR 通过调节 ULBP2 的表达来增强肝癌干细胞对 NK 细胞的敏感性。
