MiR-143 and MiR-145 regulate IGF1R to suppress cell proliferation in colorectal cancer.

Abstract

Insulin-like growth factor 1 receptor (IGF1R) is a transmembrane receptor that is activated by insulin-like growth factor 1 (IGF-1) and by a related hormone called IGF-2. It belongs to the large class of tyrosine kinase receptors and plays an important role in colorectal cancer etiology and progression. In this study, we used bioinformatic analyses to search for miRNAs that potentially target IGF1R. We identified specific target sites for miR-143 and miR-145 (miR-143/145) in the 3'-untranslated region (3'-UTR) of the IGF1R gene. These miRNAs are members of a cluster of miRNAs that have been reported to exhibit tumor suppressor activity. Consistent with the bioinformatic analyses, we identified an inverse correlation between miR-143/145 levels and IGF1R protein levels in colorectal cancer tissues. By overexpressing miR-143/145 in Caco2, HT29 and SW480 colorectal cancer cells, we experimentally validated that miR-143/145 directly recognizes the 3'-UTR of the IGF1R transcript and regulates IGF1R expression. Furthermore, the biological consequences of the targeting of IGF1R by miR-143/145 were examined by cell proliferation assays in vitro. We demonstrated that the repression of IGF1R by miR-143/145 suppressed the proliferation of Caco2 cells. Taken together, our findings provide evidence for a role of the miR-143/145 cluster as a tumor suppressor in colorectal cancer through the inhibition of IGF1R translation.

• Authors: Jiaojiao Su, Hongwei Liang, Weiyan Yao, Nan Wang, Suyang Zhang, Xin Yan, Hui Feng, Wenjing Pang, Yanbo Wang, Xueliang Wang, Zhen Fu, Yanqing Liu, Chihao Zhao, Junfeng Zhang, Chen-Yu Zhang, Ke Zen, Xi Chen, Yalei Wang
• Journal: PloS one (PLoS One) Vol. 9 Issue 12 Pg. e114420 ( 2014) ISSN: 1932-6203 [Electronic] United States
• PMID: 25474488 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• 3' Untranslated Regions
• IGF1R protein, human
• MIRN143 microRNA, human
• MIRN145 microRNA, human
• MicroRNAs
• Receptors, Somatomedin
• Receptor, IGF Type 1

Topics

• 3' Untranslated Regions
• Adenocarcinoma (genetics, metabolism, pathology)
• Base Sequence
• Binding Sites
• Caco-2 Cells
• Cell Proliferation
• Colorectal Neoplasms (genetics, metabolism, pathology)
• Gene Expression Regulation, Neoplastic
• HT29 Cells
• Humans
• MicroRNAs (physiology)
• Multigene Family
• Protein Biosynthesis
• RNA Interference
• Receptor, IGF Type 1
• Receptors, Somatomedin (genetics, metabolism)