Open AccessmiR‐34c‐3p functions as a tumour suppressor by inhibiting eIF 4E expression in non‐small cell lung cancer
Author(s) -
Liu Fang,
Wang Xuefeng,
Li Jiebing,
Gu Kuo,
Lv Liyan,
Zhang Shuai,
Che Dehai,
Cao Jingyan,
Jin Shi,
Yu Yan
Publication year - 2015
Publication title -
cell proliferation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.647
H-Index - 74
eISSN - 1365-2184
pISSN - 0960-7722
DOI - 10.1111/cpr.12201
Subject(s) - microrna , biology , cell growth , eif4e , microbiology and biotechnology , transfection , cancer research , a549 cell , western blot , cyclin d1 , cell culture , cell cycle , cell , messenger rna , gene , translation (biology) , genetics
Abstract Objectives Micro RNA s (mi RNA s) are small non‐coding RNA s that post‐transcriptionally regulate gene expression and mediate diverse physiological processes. In this study, we investigated functions of mi RNA miR‐34c‐3p in non‐small cell lung cancer ( NSCLC ). Materials and methods miR‐34c‐3p expression was evaluated by qPCR . Cell viability was examined by MTT and proliferation by cell cycle analysis. Cell migration and invasion were tested using Transwells with/without Matrigel coating. Western blot analysis was performed for eIF 4E, c‐Myc, Cyclin D1, survivin and Mcl‐1 protein expression. Results miR‐34c‐3p expression was significantly reduced in tissues and serum samples from NSCLC patients and in NSCLC cell lines A549, H460, H23, H157 and H1299. Overexpression of miR‐34c‐3p in A549 and H157 cells reduced cell proliferation, migration and invasion, whereas transfection with miR‐34c‐3p inhibitor (miR‐34c‐3p‐in) produced opposite effects. Target analysis using algorithms miRanda, TargetScan and DIANA identified eIF 4E as a potential target of miR‐34c‐3p. Luciferase assay using the eIF 4E 3′‐ UTR reporter carrying a putative miR‐34c‐3p target sequence revealed eIF 4E to be a specific target of miR‐34c‐3p. Overexpression of miR‐34c‐3p in NSCLS cell lines led to significant reduction in mRNA and protein levels of eIF 4E, whereas inhibition of miR‐34c‐3p resulted in significant increase in eI f4e protein levels, confirming eIF 4E to be a direct target of miR‐34c‐3p in NSCLS . Overexpression of eIF 4E in A549 cells promoted cell proliferation, migration and invasion, which were partially reversed by miR‐34c‐3p. Conclusion miR‐34c‐3p directly targeted eIF 4E and reduced miR‐34c‐3p expression in NSCLC , promoting cell cycle progression, proliferation, migration and invasion.