Department of Hepatobiliary and Pancreatic Surgery, Henan Provincial People's Hospital, Zhengzhou, China.
J Cell Physiol. 2020 Oct;235(10):6990-7002. doi: 10.1002/jcp.29595. Epub 2020 Jan 29.
Terminal differentiation induced ncRNA (TINCR), a newly identified lncRNA, has been found to be associated with different human cancers including hepatocellular carcinoma (HCC). However, little is known regarding the pathological mechanisms of TINCR in HCC progression. In this study, we confirmed that TINCR expression was upregulated in HCC tumors and cell lines, and high TINCR expression was associated with larger tumor size, advanced tumor node metastasis stage, and poor prognosis. Functionally, knockdown of TINCR facilitated apoptosis and suppressed viability, colony formation and invasion in Huh7 and Hep3B cells. Mechanically, TINCR functioned as competing endogenous RNA (ceRNA) to regulate DEAD-box helicase 5 (DDX5) expression through sponging miR-218-5p. Moreover, the miR-218-5p expression was downregulated and DDX5 expression was upregulated in HCC tumors. The silencing of miR-218-5p or ectopic expression of DDX5 abated the tumor-suppressive effect of TINCR knockdown in vitro. Furthermore, si-TINCR-induced inactivation of AKT signaling was rescued by suppression of miR-218-5p or overexpression of DDX5. Also, the silencing of TINCR resulted in tumor growth inhibition in vivo. In summary, knockdown of TINCR suppressed HCC progression presumably by inactivation of AKT signaling through targeting the miR-218-5p/DDX5 axis, suggesting a novel TINCR/miR-218-5p/DDX5 pathway and therapy target for HCC.
终端分化诱导非编码 RNA(TINCR)是一种新鉴定的 lncRNA,已被发现与包括肝细胞癌(HCC)在内的不同人类癌症有关。然而,关于 TINCR 在 HCC 进展中的病理机制知之甚少。在这项研究中,我们证实 TINCR 在 HCC 肿瘤和细胞系中表达上调,并且高 TINCR 表达与更大的肿瘤大小、更晚期的肿瘤淋巴结转移分期和不良预后相关。功能上,敲低 TINCR 促进了 Huh7 和 Hep3B 细胞的凋亡,并抑制了其活力、集落形成和侵袭能力。机制上,TINCR 通过海绵 miR-218-5p 作为竞争性内源 RNA(ceRNA)来调节 DEAD-box 螺旋酶 5(DDX5)的表达。此外,miR-218-5p 在 HCC 肿瘤中表达下调,DDX5 表达上调。在体外,沉默 miR-218-5p 或过表达 DDX5 减弱了 TINCR 敲低的肿瘤抑制作用。此外,si-TINCR 诱导的 AKT 信号失活可通过抑制 miR-218-5p 或过表达 DDX5 得到挽救。同样,TINCR 的沉默导致体内肿瘤生长抑制。总之,敲低 TINCR 通过靶向 miR-218-5p/DDX5 轴抑制 AKT 信号失活,可能抑制 HCC 进展,提示 HCC 中存在新的 TINCR/miR-218-5p/DDX5 通路和治疗靶点。