Identification of mir-342-3p functionally associated with transcriptional activity of MYC in lung cancer [cell culture]

ABSTRACT: Accumulating evidence indicates that altered miRNA expression is crucially involved in lung cancer development, but only little has been elucidated about how MYC, an archetypical oncogene, is regulated by miRNAs, especially through a mechanism involving the MYC cofactor(s). In this study, we aimed at identifying miRNAs involved in the regulation of MYC transcriptional activity in lung cancers. To this end, we have taken an integrative approach with combinatorial usage of miRNA and mRNA expression profile datasets of patientsâ?? tumor tissues as well as those of MYC-inducible cell lines in vitro. We report here that in addition to miRNAs previously reported to be directly regulating or regulated by MYC including let-7 and miR-17-92, our strategy allowed us to identify miR-342-3p as the one capable of indirectly regulating MYC activity through direct repression of a MYC-cooperating molecule, E2F1. Furthermore, the miR-342-3p module activity, which we defined as a gene set reflecting experimentally substantiated influence of miR-342-3p on mRNA expression, was found to be inversely correlated with MYC activity reflected in the MYC module activity in three independent datasets of lung adenocarcinoma patients obtained by the Directorâ??s Challenge Consortium of the United States (P=1.94x10-73), the National Cancer Center of Japan (P=9.05x10-34) and our own in this study (P=3.37x10-6). Our integrative approach thus appears to be useful to elucidate inter-regulatory relationships between miRNAs and a protein coding-gene of interest, even those present in tumor tissues in patients, which still remains a challenge to better understand the pathogenesis of this devastating disease. Microarray analysis using a SurePrint G3 Human GE 8 x 60K Microarray G4851A (Agilent) was conducted. Tai, MeiChee

ORGANISM(S): Homo sapiens

SUBMITTER: Takashi Takahashi 

PROVIDER: E-GEOD-66758 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress