The Novel Long Noncoding RNA TUSC7 Inhibits Proliferation by Sponging MiR-211 in Colorectal Cancer

Abstract

Background/Aims: The novel long noncoding RNA (lncRNA) tumor suppressor candidate 7 (TUSC7) has been reported as a potential tumor suppressor, while the functional role of TUSC7 is still unknown in colorectal cancer (CRC). Here, we characterized TUSC7 expression profile in CRC patients and investigated its biological function and potential molecular mechanism. Methods: RNA isolation, qRT-PCR, cell counter kit-8 assay, cell cycle assay, EdU assay, and western blot were performed. Statistical analyses were performed using SPSS 18.0 software and p value < 0.05 was considered as statistically significant. Results: In a cohort of CRC patients, we found TUSC7 was significantly downregulated in CRC tissues compared with adjacent non-tumor tissues (P < 0.01). Patients with high expression of TUSC7 had better survival than those with low expression of TUSC7 (HR = 0.342, 95% CI: 0.120-0.972, P = 0.044). Cell count kit 8 and EdU assays showed that ectopic expression of TUSC7 in HCT116 and SW480 cells significantly inhibited cell proliferation rate. After silence of TUSC7 with small interfering RNA, cell proliferation rate increased. Flow cytometry analyses revealed cycles were arrested at G1 phase after TUSC7 overexpression. We found there were 2 binding sites of miR-211-3p within the sequence of TUSC7 and TUSC7 expression level was negatively correlated with miR-211-3p. TUSC7 overexpression increased the expression level of CDK6, which is a downstream target of miR-211-3p, in both RNA and protein level. Furthermore, luciferase reporter assay indicated that TUSC7 could sponge miR-211-3p. Conclusion: To summary, we demonstrated that TUSC7 is a potential tumor suppressor in CRC, and TUSC7 could inhibit CRC cell proliferation by completely sponging miR-211-3p.

LncRNA SNHG6 is Associated with Poor Prognosis of Gastric Cancer and Promotes Cell Proliferation and EMT through Epigenetically Silencing p27 and Sponging miR-101-3p

“…Currently, the newly uncovered lncRNAs, emerged as important factors in cellular processes and human diseases, have been attracting more and more attentions of researchers. For example, novel lncRNA TUSC7 was identified dysregulated in colorectal cancer and regulating cell proliferation through sponging miR-211 [28]. And lncRNA TRPM2-AS was demonstrated as novel prognostic marker and therapeutic target in prostate cancer [29].…”

lncRNA FAM83H‑AS1 is associated with the prognosis of colorectal carcinoma and promotes cell proliferation by targeting the Notch signaling pathway

“…lncRNAs have been reported to be involved in a variety of biological processes, including tumorigenesis through regulating oncogenes or tumor suppressors at several levels (3)(4)(5)(6)(7)(8)(9)(10)(11)(12). For example, Xia et al (13) demonstrated that long noncoding RNA papillary thyroid carcinoma susceptibility candidate 3 (PTCSC3) inhibited proliferation and invasion of glioma cells by suppressing the Wnt/β-catenin signaling pathway.…”

Analysis of lncRNA-Associated ceRNA Network Reveals Potential lncRNA Biomarkers in Human Colon Adenocarcinoma

“…To better understand and identify efficient new biomarkers of COAD, we are studying the mechanisms of COAD. Recent studies have shown that lncRNAs play vital roles in the development of cancer [2,3,[18][19][20][21], but there have been very few studies that focused on the profiles of lncRNAs in CRC. lncRNAs mRNA targets HOTAIR REV3L, INO80D, PHIP, AGO3, TAOK1, ATM, GPATCH2L, RC3H1, SHPRH, RICTOR, MAP3K2, ATAD2B, RIC1, PIKFYVE, WDPCP, USP34, PHC3, MIR133A1HG, BRWD1, ZBTB37 LINC00355 ATM, REV3L, GPATCH2L, RICTOR, SHPRH, PHIP, AGO3, WDPCP, INO80D, RIC1, RC3H1, TAOK1, USP34, ATAD2B, MFSD4B, FAM217A, PIKFYVE, ZBTB37, NBEAL1, GDAP2 TSSC1-IT1 SHPRH, INO80D, LRRTM2, TNRC6B, GPATCH2L, PHC3, GPR52, RC3H1, AGO3, ZBTB20, REV3L, NBEAL1, RNF169, TAS2R19, MFSD4B, IFNK, CLDN20, RIC1, FBXL13, MATR3 KCNQ1OT1 SHPRH, INO80D, AGO3, LRRTM2, RC3H1, MIR133A1HG, GPATCH2L, REV3L, MATR3, ZBTB20, PHC3, GPR52, GDAP2, POU5F2, MFSD4B, NBEAL1, TAS2R19, ATM, C1orf195, AIRN LncRNAs have sophisticated functions through diverse pathways, and the ceRNA hypothesis makes the relationship between lncRNAs, miRNAs, and mRNAs more complicated.…”