Dataset Information

MiRNA-483-3p overexpression unleashes invasive growth of metastatic colorectal cancer via NDRG1 downregulation and ensuing activation of the ERBB3/AKT axis

ABSTRACT: Colorectal cancer is a prevalent disease that is the third most common cause of cancer-associated death globally. The genetic mechanisms underlying tumor aggressiveness in colorectal cancer require further elucidation. Taking advantage of a large panel of human metastatic colorectal cancer xenografts and matched stem-like cell cultures (m-colospheres), we show here that overexpression of miRNA-483-3p, encoded by a frequently amplified gene locus encompassing IGF2, confers an aggressive phenotype. Following ectopic overexpression of miRNA-483-3p, m-colospheres displayed (i) increased proliferative response to exogenous EGFR family ligands EGF and neuregulin 1; (ii) increased spontaneous and growth factor-induced invasiveness and epithelial-mesenchymal transition (EMT); and (iii) enhanced stem-cell frequency and resistance to differentiation. Transcriptomic analyses and functional validation found that miRNA-483-3p directly targets NDRG1, a known metastasis suppressor responsible for downregulation of the EGFR family. As a result, induced or endogenous miRNA-483-3p overexpression associated with stimulation of the signaling pathway triggered by ERBB3, including AKT and GSK3β, which is responsible for EMT transcription factor activation. Consistently, treatment of miRNA-483-3p-overexpressing m-colospheres with selective ERBB3 antibodies counteracted their proliferative and invasive phenotype. The pro-malignant role of miRNA-483-3p was further corroborated by analysis of human colorectal tumors, where miRNA-483-3p expression levels directly correlated with expression of EMT transcription factors and poor prognosis, and downregulation of miRNA-483-3p, which prevented invasion of tumors formed by m-colosphere transplantation. These results unveil a previously unrecognized link between miRNA-483-3p, NDRG1, and ERBB3-AKT signaling, which can directly support colorectal cancer invasion and is amenable to therapeutic targeting.

ORGANISM(S): Homo sapiens

PROVIDER: GSE209535 | GEO | 2023/03/13

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:Epithelial-mesenchymal transition (EMT) has recently been recognized as a key element of cell invasion, migration, metastasis, and drug resistance in several types of cancer, including non-small cell lung cancer (NSCLC). Our aim was to clarify microRNA (miRNA) -related mechanisms underlying EMT followed by acquired resistance to epidermal growth factor receptor tyrosine-kinase inhibitor (EGFR-TKI) in NSCLC. MiRNA expression profiles were examined before and after transforming growth factor-beta1 (TGF-M-NM-21) exposure in four human adenocarcinoma cell lines with or without EMT. Correlation between expressions of EMT-related miRNAs and resistance to EGFR-TKI gefitinib was evaluated. MiRNA array and quantitative RT-PCR revealed that TGF-M-NM-21 significantly induced overexpression of miR-134, miR-487b, and miR-655, which belong to the same cluster located on chromosome 14q32, in lung adenocarcinoma cells with EMT. MAGI2 (membrane-associated guanylate kinase, WW and PDZ domain-containing protein 2), a predicted target of these miRNAs and a scaffold protein required for PTEN (phosphatase and tensin homolog), was diminished in A549 cells with EMT after the TGF-M-NM-21 stimulation. Overexpression of miR-134 and miR-487b promoted the EMT phenomenon and affected the drug resistance to gefitinib, whereas knockdown of these miRNAs inhibited the EMT process and reversed TGF-M-NM-21-induced resistance to gefitinib. Our study demonstrated that the miR-134/487b/655 cluster contributed to the TGF-M-NM-21-induced EMT phenomenon and affected the resistance to gefitinib by directly targeting MAGI2, whose suppression subsequently caused loss of PTEN stability in lung cancer cells. The miR-134/miR-487b/miR-655 cluster may be new therapeutic targets in advanced lung adenocarcinoma patients, depending on the EMT phenomenon. miRNA expression profiles before and after TGF-M-NM-21 exposure were assessed in the four lung adenocarcinoma cell lines, A549, LC2/ad, PC3, and, PC9 by TaqMan miRNA arrays. Relative ratios of miRNAs in cells after TGF-M-NM-21 exposure were calculated when compared with the cells before TGF-M-NM-21 exposure.

Project description:Using a retrovirus-mediated cDNA expression cloning approach we identified the grainyhead-like 2 (GRHL2) transcription factor as novel protooncogene. Overexpression of GRHL2 in NIH3T3 cells induced striking morphological changes, an increase in cell proliferation, anchorage-independent growth, and tumor growth in vivo. By combining a microarray analysis and a phylogenetic footprinting analysis with various biochemical assays we identified the epidermal growth factor receptor family member Erbb3 as a novel GRHL2 target gene. In breast cancer cell lines, shRNA-mediated knockdown of GRHL2 expression or functional inactivation of GRHL2 using dominant-negative GRHL2 proteins induce downregulation of ERBB3 gene expression, a striking reduction in cell proliferation and morphological and phenotypical alterations characteristic of an epithelial-to-mesenchymal transition (EMT), thus implying dual roles of GRHL2 in breast carcinogenesis. Interestingly, we could further demonstrate that expression of GRHL2 is directly suppressed by the transcription factor zinc-finger-enhancer binding protein 1 (ZEB1) which in turn is a direct target for repression by GRHL2, suggesting that the EMT transcription factors GRHL2 and ZEB1 form a double negative regulatory feedback loop in breast cancer cells. Finally, a comprehensive immunohistochemical analysis of GRHL2 expression in primary breast cancers showed loss of GRHL2 expression at the invasive front of primary tumors. A pathophysiological relevance of GRHL2 in breast cancer metastasis is further demonstrated by our finding of a statistically significant association between loss of GRHL2 expression in primary breast cancers and lymph-node metastasis. We thus demonstrate a crucial role of GRHL2 in breast carcinogenesis. To evaluate the role of the GRHL2 transcription factor in carcinogenessis we overexpressed the human GRHL2 protein in NIH3T3 cells. Parental NIH3T3 cells do not express the orthologic protein. Alterations in genome-wide transcriptional profiles were determined by microarray analysis.

Dataset Information

MiRNA-483-3p overexpression unleashes invasive growth of metastatic colorectal cancer via NDRG1 downregulation and ensuing activation of the ERBB3/AKT axis

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure