MicroRNA-203 inhibits cellular proliferation and invasion by targeting Bmi1 in non-small cell lung cancer

Abstract

Abstract. MicroRNAs are proposed to serve vital functions in the regulation of tumor progression and invasion. However, the expression levels of miR-203 in non-small cell lung cancer (NSCLC) and its clinical significance remain unknown. In the present study, the association between B-cell-specific moloney murine leukemia virus insertion site 1 (Bmi1) and miR-203 was investigated. miR-203 was demonstrated to act as a tumor suppressor by regulating the expression of Bmi1. miR-203 expression levels were downregulated in NSCLC tissues while Bmi1 expression was upregulated in NSCLC tissues and cell lines. Furthermore, downregulated Bmi1 or enhanced miR-203 expression inhibited NSCLC cell proliferation and invasion in vitro. In addition, a dual-luciferase reporter assay was performed, which identified Bmi1 as a novel target of miR-203. In conclusion, the present study demonstrated that miR-203 functions as a tumor suppressor and is important in inhibiting the proliferation of NSCLC cells through targeting Bmi1. These findings indicate that miR-203 may be useful as a novel potential therapeutic target for NSCLC.

Serum microRNA-135a downregulation as a prognostic marker of non-small cell lung cancer

“…Moreover, miR-224 was found to promote NSCLC progression by inhibiting the expression of TNFAIP1 and SMAD4, indicating that miR-224 could be a potential target for NSCLC treatment. In contrast, Chen et al (2015) reported a marked reduction in the expression of miR-203 in NSCLC tissues, compared to that in adjacent tissues; additionally, miR-203 overexpression was found to effectively restrain cancer cell proliferation and invasion in vitro, implying the tumor suppressing role of miR-203 in NSCLC oncogenesis Therefore, miRNA may promote or inhibit NSCLC oncogenesis, with the specific effect possibly being correlated with the tumor microenvironment and downstream targets.…”

MiR-203 inhibits estrogen-induced viability, migration and invasion of estrogen receptor α-positive breast cancer cells

“…Recently, miR-203 has been implicated in numerous types of human cancer, such as gastric carcinoma (31), hepatocellular carcinoma (32) and lung cancer (33). It was reported to be significantly downregulated in gastric carcinoma and to promote cancer metastasis via inhibition of Slug (31).…”

“…MiR-203 also suppresses the proliferation and metastasis of hepatocellular carcinoma by targeting ADAM9 and long non-coding RNA HULC (32). Chen et al (33) found that miR-203 inhibited the proliferation and invasion of non-small cell lung cancer cells by targeting Bmi1. In addition, miR-203 suppresses proliferation and induces apoptosis of human oral cancer cells (34).…”

MicroRNA‑154 functions as a tumor suppressor in non‑small cell lung cancer through directly targeting B‑cell‑specific Moloney murine leukemia virus insertion site 1

“…Increasing studies have demonstrated that microRNAs (miRNAs/miRs) have vital functions in numerous developmental processes and tumorigenesis, including the progression of NSCLC (6)(7)(8). miRNAs represent a group of small (~19-25 nucleotides), non-protein-coding, and endogenous single RNAs, which negatively regulate gene expression by binding to the 3' untranslated regions (3'UTRs) of target genes in an imperfect base pairing manner, causing mRNA cleavage or translational repression (9,10).…”