[Expression of long-chain non-coding RNA LINC00152 in laryngeal squamous cell carcinoma and its clinical significance]

Long non-coding RNA LINC00152 in cancer: Roles, mechanisms, and chemotherapy and radiotherapy resistance

Long non-coding RNA LINC00152 (cytoskeleton regulator, or LINC00152) is an 828-bp lncRNA located on chromosome 2p11.2. LINC00152 was originally discovered during research on hepatocarcinogenesis and has since been regarded as a crucial oncogene that regulates gene expression in many cancer types. LINC00152 is aberrantly expressed in various cancers, including gastric, breast, ovarian, colorectal, hepatocellular, and lung cancer, and glioma. Several studies have indicated that LINC00152 is correlated with cell proliferation, apoptosis, migration, invasion, cell cycle, epithelial-mesenchymal transition (EMT), chemotherapy and radiotherapy resistance, and tumor growth and metastasis. High LINC00152 expression in most tumors is significantly associated with poor patient prognosis. Mechanistic analysis has demonstrated that LINC00152 can serve as a competing endogenous RNA (ceRNA) by sponging miRNA, regulating the abundance of the protein encoded by a particular gene, or modulating gene expression at the epigenetic level. LINC00152 can serve as a diagnostic or prognostic biomarker, as well as a therapeutic target for most cancer types. In the present review, we discuss the roles and mechanisms of LINC00152 in human cancer, focusing on its functions in chemotherapy and radiotherapy resistance.

The emerging role of super enhancer-derived noncoding RNAs in human cancer

Super enhancers (SEs) are large clusters of adjacent enhancers that drive the expression of genes which regulate cellular identity; SE regions can be enriched with a high density of transcription factors, co-factors, and enhancer-associated epigenetic modifications. Through enhanced activation of their target genes, SEs play an important role in various diseases and conditions, including cancer. Recent studies have shown that SEs not only activate the transcriptional expression of coding genes to directly regulate biological functions, but also drive the transcriptional expression of non-coding RNAs (ncRNAs) to indirectly regulate biological functions. SE-derived ncRNAs play critical roles in tumorigenesis, including malignant proliferation, metastasis, drug resistance, and inflammatory response. Moreover, the abnormal expression of SE-derived ncRNAs is closely related to the clinical and pathological characterization of tumors. In this review, we summarize the functions and roles of SE-derived ncRNAs in tumorigenesis and discuss their prospective applications in tumor therapy. A deeper understanding of the potential mechanism underlying the action of SE-derived ncRNAs in tumorigenesis may provide new strategies for the early diagnosis of tumors and targeted therapy.

Long Non-Coding RNA NRAD1 and LINC00152 are Highly Expressed and Associated with Prognosis in Patients with Hepatocellular Carcinoma

Background

Hepatocellular carcinoma (HCC) is prevalent throughout the world. The aim of this study is to explore new long non-coding RNAs (lncRNAs) associated with hepatocellular carcinoma and detect their expression levels in hepatocellular carcinoma cell lines and tissues. These results will provide new clues on further function and biomarker studies of HCC-related lncRNAs.

Patients and Methods

All patients were diagnosed as HCC between 30th, March, 2015 and 30th, July, 2018. LncRNA human gene expression microarray was applied to the profiling of lncRNAs in four cancerous tissues and the paired paracancerous tissues.

Results

We retrospectively reviewed 63 patients with primary HCC who underwent a curative liver resection at the Department of Hepatology, Qingdao Sixth People’s Hospital. The expression level of lncRNA NRAD1 and LINC00152 was detected by real-time PCR. Prognostic factors were evaluated using Kaplan–Meier curves and Cox proportional hazards models. By microarray profiling of lncRNAs, 256 lncRNAs were found to be differentially expressed, including 162 upregulated and 94 downregulated (P<0.05, fold change>2). Two candidate lncRNAs were determined as the targets in this study, which were NRAD1 (upregulated by 6.35 fold), LINC00152 (upregulated by 4.53 fold). NRAD1 and LINC00152 were downregulated in the normal liver cell lines Chang liver, HL7702, THLE-2, THLE-3, FL62891 and AML12, which were significantly lower than HCC cell lines SMMC-7721, Hep3B, HuH7, MHCC-97H, HCC-LM and SK-Hep-1 (P<0.05). Overexpression of lncRNA NRAD1 and LINC00152 was associated with decreasing OS rates, respectively (P=0.0263 and P=0.0285). Meanwhile, overexpression of NRAD1 and LINC00152 was associated with decreasing PFS rates, respectively (P=0.0174 and P=0.0041). After adjusting for competing risk factors, we identified that microvascular invasion (P=0.014), tumor size (P=0.026), lncRNA NRAD1 (P=0.001) and LINC00152P9 (P=0.036) expression levels were independent prognostic factors associated with prognosis of patients with HCC.

Conclusion

We found lncRNA NRAD1 and LINC00152 expressed significantly higher in HCC tissues compared with non-tumorous tissues. Overexpression of lncRNA NRAD1 and LINC00152 were independent risk factors associated with the prognosis of patients with HCC.

LncRNA LINC00152 Promotes Laryngeal Cancer Progression by Sponging MiR-613

Background

Long noncoding RNA (lncRNA) LINC00152 (CYTOR) has been reported to be upregulated and to serve as a diagnostic biomarker in multiple types of cancers, including laryngeal squamous cell cancer (LSCC). However, the functional role and molecular mechanisms of LINC00152 in LSCC progression need to be further investigated.

Methods

LINC00152 levels in LSCC and adjacent normal tissues were measured by quantitative real-time polymerase chain reaction (qRT-PCR). Gene knockdown of LINC00152 was achieved in LSCC cells by use of small interfering RNA (siRNA). Cell proliferation, apoptosis, migration and invasion were examined by a series of methods. The micoRNA (miRNA) interaction with LINC00152 was screened by starBase v2.0 and confirmed by luciferase reporter activity.

Results

LINC00152 levels in LSCC tissues were significantly higher than those in adjacent normal tissue, and patients with lymph node metastasis or an advanced clinical stage displayed higher LINC00152 expression. Moreover, siRNA-mediated LINC00152 knockdown significantly inhibited the proliferation, migration and invasion of LSCC cells and induced apoptosis in those cells. Mechanistically, LINC00152 functioned as a competing endogenous RNA (ceRNA) sponging miR-613. The inhibitory effect of LINC00152 knockdown on malignant behavior was abrogated by inhibiting miR-613.

Conclusion

LINC00152 exerts an oncogenic effect on the tumorigenesis of LSCC by sponging miR-613 and may serve as a potential target for treating LSCC.