Project description: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
Project description: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 Directorâs 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.
Project description: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 patients’ 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 Director’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.
Project description: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 patients’ 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 Director’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.
Project description:Oxaliplatin (oxPt) resistance in colorectal cancers (CRC) is a major unsolved problem. Consequently, predictive markers and a better understanding of resistance mechanisms are urgently needed. To investigate if the recently identified predictive miR-625-3p is functionally involved in oxPt resistance, stable and inducible models of miR-625-3p dysregulation were analyzed. Ectopic expression of miR-625-3p in CRC cells led to increased resistance towards oxPt. The mitogen-activated protein kinase (MAPK) kinase 6 (MAP2K6/MKK6) – an activator of p38 MAPK - was identified as a functional target of miR-625-3p, and, in agreement, was down-regulated in patients not responding to oxPt therapy. The miR-625-3p resistance phenotype could be reversed by anti-miR-625-3p treatment and by ectopic expression of a miR-625-3p insensitive MAP2K6 variant. Transcriptome, proteome and phosphoproteome profiles revealed inactivation of MAP2K6-p38 signaling as a possible driving force behind oxPt resistance. We conclude that miR-625-3p induces oxPt resistance by abrogating MAP2K6-p38 regulated apoptosis and cell cycle control networks.
Project description:RAW264.7 mouse macrophages were transfected with negative control and miR-342-3p mimics and subjected to microarray analysis 18 hours after the transfection. We used microarray to obtain global mRNA expression data of negative control and miR-342-3p mimics-transfected RAW264.7 cells.
Project description:Hepatocellular carcinoma (HCC) is a cancer with global impact and largely refractory to current treatments. Novel treatment options are therefore urgently needed. MicroRNAs play important regulatory roles in HCCs and are emerging as promising therapeutic options against HCC. We identified tumor suppressor miRNAs that may attenuate tumor development and contribute to HCC regression. We identified miR-342-3p as a promising tumor suppressor miRNA. To understand how miR-342-3p affects the global landscape of gene expression, we transfected Huh7 human hepatoma cells with either the scramble control, or a mimic for miR-342-3p and performed mRNA expression profiling.
Project description:To Identify of metastasis-related genes and metastasis-related miRNA in oral squamous cell carcinoma by miRNA profiling of HOC313-Parent, HOC313-LM and their respective exosomes carried out. As a result, miR-342-3p and -1246 were found candidate oncogenic miRNAs. To further identify the target genes of miR-1246 and miR-342-3p, we performed gene expression array analysis with HOC313-LM and HOC313-Parent (HOC313-P) transfected NT, miR-342-3p and miR-1246. Moreover, to identify tumor suppressor genes, gene expression profiles of each of transfected cells and HOC313-LM cells were analyzed by in silico analyses. As a result, DENND2D emerged as the possible target of miRN-1246.