TargetRx Atlas

MRNA basic information

  • mRNA ID:ENST00000263967
  • Gene Name:PI3K
  • mRNA database:Ensembl
  • mRNA expression :up-regulated
  • mRNA Method:qRT-PCR
  • mRNA Pathway:NA
  • Evidence:predicted
  • (mRNA-drug)

Drug basic information

  • Drug ID:NA
  • Drug Name:NA
  • Drug Method:NA

Disease basic infommation

  • Disease:breast cancer
  • Tissue:MCF-7, T47d, MDA-MB-231, BT549 and HBL-100 cell lines

Other information

  • Title:MiR-122 inhibits cell proliferation and tumorigenesis of breast cancer by targeting IGF1R.
  • Journal:PloS one
  • Published:2012
  • PubMed ID:23056576
  • Abstract:miRNAs are emerging as critical regulators in carcinogenesis and tumor progression. Recently, microRNA-122 (miR-122) has been proved to play an important role in hepatocellular carcinoma, but its functions in the context of breast cancer (BC) remain unknown. In this study, we report that miR-122 is commonly downregulated in BC specimens and BC cell lines with important functional consequences. Overexpression of miR-122 not only dramatically suppressed cell proliferation, colony formation by inducing G1-phase cell-cycle arrest in vitro, but also reduced tumorigenicity in vivo. We then screened and identified a novel miR-122 target, insulin-like growth factor 1 receptor (IGF1R), and it was further confirmed by luciferase assay. Overexpression of miR-122 would specifically and markedly reduce its expression. Similar to the restoring miR-122 expression, IGF1R downregulation suppressed cell growth and cell-cycle progression, whereas IGF1R overexpression rescued the suppressive effect of miR-122. To identify the mechanisms, we investigated the Akt/mTOR/p70S6K pathway and found that the expression of Akt, mTOR and p70S6K were suppressed, whereas re-expression of IGF1R which did not contain the 3'UTR totally reversed the inhibition of Akt/mTOR/p70S6K signal pathway profile. We also identified a novel, putative miR-122 target gene, PI3CG, a member of PI3K family, which further suggests miR-122 may be a key regulator of the PI3K/Akt pathway. In clinical specimens, IGF1R was widely overexpressed and its mRNA levels were inversely correlated with miR-122 expression. Taken together, our results demonstrate that miR-122 functions as a tumor suppressor and plays an important role in inhibiting the tumorigenesis through targeting IGF1R and regulating PI3K/Akt/mTOR/p70S6K pathway. Given these, miR-122 may serve as a novel therapeutic or diagnostic/prognostic-target for treating BC.