Entrez Gene

General information | Expression | Regulation | Mutation | Interaction

Basic Information
Gene ID	406937
Name	MIR145
Synonymous	MIRN145\|miR-145\|miRNA145;microRNA 145;MIR145;microRNA 145
Definition	-
Position	5q32
Gene type	miscRNA
Source	Count: 1; Generif
Sentence	Abstract
"This study, we performed a comprehensive analysis of putative human miRNA oncogenes and tumor suppressors. We found that miRNA oncogenes and tumor suppressors clearly show different patterns in function, evolutionary rate, expression, chromosome distribution, molecule size, free energy, transcription factors, and targets."	microRNAs (miRNAs) are small noncoding RNAs which play essential roles in many important biological processes. Therefore, their dysfunction is associated with a variety of human diseases, including cancer. Increasing evidence shows that miRNAs can act as oncogenes or tumor suppressors, and although there is great interest in research into these cancer-associated miRNAs, little is known about them. In this study, we performed a comprehensive analysis of putative human miRNA oncogenes and tumor suppressors. We found that miRNA oncogenes and tumor suppressors clearly show different patterns in function, evolutionary rate, expression, chromosome distribution, molecule size, free energy, transcription factors, and targets. For example, miRNA oncogenes are located mainly in the amplified regions in human cancers, whereas miRNA tumor suppressors are located mainly in the deleted regions. miRNA oncogenes tend to cleave target mRNAs more frequently than miRNA tumor suppressors. These results indicate that these two types of cancer-associated miRNAs play different roles in cancer formation and development. Moreover, the patterns identified here can discriminate novel miRNA oncogenes and tumor suppressors with a high degree of accuracy. This study represents the first large-scale bioinformatic analysis of human miRNA oncogenes and tumor suppressors. Our findings provide help for not only understanding of miRNAs in cancer but also for the specific identification of novel miRNAs as miRNA oncogenes and tumor suppressors. In addition, the data presented in this study will be valuable for the study of both miRNAs and cancer.
"Data show that IGF-IR resistant to miR145 is not down-regulated by miR145 but fails to rescue colon cancer cells from growth inhibition, and indicate that down-regulation of IRS-1 plays a significant role in the tumor suppressor activity of miR145."	microRNA 145 (miR145) has been proposed as a tumor suppressor. It was previously shown that miR145 targets the 3' UTR of the insulin receptor substrate-1 (IRS-1) and dramatically inhibits the growth of colon cancer cells. miR145 also targets the type 1 insulin-like growth factor receptor (IGF-IR). We show here that an IRS-1 lacking its 3' UTR is no longer down-regulated by miR145 and rescues colon cancer cells from miR145-induced inhibition of growth. An IGF-IR resistant to miR145 (again by elimination of its 3' UTR) is not down-regulated by miR145 but fails to rescue colon cancer cells from growth inhibition. These and other results, taken together, indicate that down-regulation of IRS-1 plays a significant role in the tumor suppressor activity of miR145.