Zhuang Zehang, Huang Jing, Wang Weiwang, Wang Cheng, Yu Pei, Hu Jing, Liu Haichao, Yin Hanqi, Hou Jinsong, Liu Xiqiang
Department of Oral and Maxillofacial Surgery, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China.
Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, China.
Front Oncol. 2021 Feb 25;10:624752. doi: 10.3389/fonc.2020.624752. eCollection 2020.
Recently long non-coding RNAs (lncRNAs) have emerged as novel gene regulators involved in tumorigenic processes, including oral squamous cell carcinoma (OSCC). Here, we identified a differentiation-related lncRNA, terminal differentiation-induced non-coding RNA (TINCR). However, its biological function and clinicopathological significance in OSCC still remain unclear.
The lncRNA expression profiles in OSCC tissues and paired adjacent non-tumor tissues (NATs) from 10 patients were detected by lncRNA microarrays. Weighted gene co-expression network analysis (WGCNA) and gene ontology (GO) enrichment were performed to identify the most significant module and module functional annotation, respectively. Potential differentiation-related lncRNAs were screened by differential expression analysis. TINCR was further confirmed in OSCC cell lines and tissues of another patient cohort by using qRT-PCR. The correlation between the TINCR expression level and clinicopathological characteristics was analyzed. The effects of TINCR on cell differentiation, migration and invasion were assessed by knockdown or knock-in and .
WGCNA and GO enrichment analysis showed that one co-expression network was significantly enriched for epithelial cell differentiation, among which, TINCR was significantly downregulated. qRT-PCR analyses validated down-regulation of TINCR in tumor tissues compared with paired NATs, and its expression was closely correlated with pathological differentiation and lymph node metastasis in patients with OSCC. Patients with lower TINCR expression levels had worse survival. Cell function experiments showed that TINCR played a crucial role in epithelial differentiation. Both TINCR and epithelial differentiation-associated genes, including IVL and KRT4, were significantly upregulated during OSCC cell calcium-induced differentiation but were reduced when cell dedifferentiation occurred in tumor spheres. Overexpression of TINCR dramatically suppressed cell dedifferentiation, migration and invasion , while knockdown of TINCR had the opposite effects. Upregulation of TINCR significantly elevated the expression of terminal differentiation genes and repressed tumor growth . Moreover, TINCR significantly suppressed the activation of JAK2/STAT3 signaling in OSCC cells.
Our study suggests that TINCR functions as a tumor suppressor by inducing cell differentiation through modulating JAK2/STAT3 signaling in OSCC. TINCR may serve as a prognostic biomarker and therapeutic target for OSCC.
近年来，长链非编码RNA（lncRNAs）已成为参与肿瘤发生过程的新型基因调节因子，包括口腔鳞状细胞癌（OSCC）。在此，我们鉴定出一种与分化相关的lncRNA，即终末分化诱导非编码RNA（TINCR）。然而，其在OSCC中的生物学功能和临床病理意义仍不清楚。
通过lncRNA芯片检测10例患者OSCC组织及配对的相邻非肿瘤组织（NATs）中的lncRNA表达谱。分别进行加权基因共表达网络分析（WGCNA）和基因本体（GO）富集分析，以确定最显著的模块和模块功能注释。通过差异表达分析筛选潜在的与分化相关的lncRNAs。使用qRT-PCR在另一患者队列的OSCC细胞系和组织中进一步验证TINCR。分析TINCR表达水平与临床病理特征之间的相关性。通过敲低或敲入评估TINCR对细胞分化、迁移和侵袭的影响。
WGCNA和GO富集分析表明，一个共表达网络在上皮细胞分化方面显著富集，其中TINCR显著下调。qRT-PCR分析证实，与配对的NATs相比，肿瘤组织中TINCR表达下调，且其表达与OSCC患者的病理分化和淋巴结转移密切相关。TINCR表达水平较低的患者生存率较差。细胞功能实验表明，TINCR在上皮分化中起关键作用。在OSCC细胞钙诱导分化过程中，TINCR和包括IVL和KRT4在内的上皮分化相关基因均显著上调，但在肿瘤球中细胞去分化时则降低。TINCR的过表达显著抑制细胞去分化、迁移和侵袭，而敲低TINCR则产生相反的效果。TINCR的上调显著提高终末分化基因的表达并抑制肿瘤生长。此外，TINCR显著抑制OSCC细胞中JAK2/STAT3信号通路的激活。
我们的研究表明，TINCR在OSCC中通过调节JAK2/STAT3信号通路诱导细胞分化，从而发挥肿瘤抑制作用。TINCR可能作为OSCC的预后生物标志物和治疗靶点。
