hsa-miR-21

breast cancer

Relationship type:

Causal

Detection method for miRNA expression:

Northern blot, qRT-PCR etc

up-regulated

Validated targets of miRNA from the reference:

unknown

Validated targets of miRNA from TarBase:

PTEN,TPM1 : More...

Description:

MicroRNA-21 (miR-21) is considered an onco-microRNA given its abilities to suppress the actions of several tumor suppressor genes and to promote tumor cell growth, invasion and metastasis. Recently, transforming growth factor-beta (TGF-beta) is found to up-regulate the expression of miR-21, and elevated miR-21 expression is seen frequently in breast cancer. The study results showed that the expression of miR-21 was detected in all tumor samples with substantial variation. High miR-21 expression was associated with features of aggressive disease, including high tumor grade, negative hormone receptor status, and ductal carcinoma. High miR-21 was also positively correlated with TGF-beta1. No associations were found between patient survival and miR-21 expression among all patients, but high miR-21 was associated with poor disease-free survival in early stage patients (HR=2.08, 95% CI:1.08-4.00) despite no value for prognosis. The study supports the notion that miR-21 is an onco-microRNA for breast cancer. Elevated miR-21 expression may facilitate tumor progression, and TGF-beta may up-regulate its expression.

Reference:

High miR-21 expression in breast cancer associated with poor disease-free survival in early stage disease and high TGF-beta1. | PMID:18932017
Qian B, Katsaros D, Lu L, Preti M, Durando A, Arisio R, Mu L, Yu H.
Breast Cancer Res Treat. 2008 Oct 19. [Epub ahead of print]