MiRNA-26b inhibits cellular proliferation by targeting CDK8 in breast cancer.
Year: 2014
Type: article
Abstract: OBJECTIVES: MicroRNA-26b (miR-26b) has been reported to be down-regulated in a wide range of malignant tumors, However, the mechanism by which miR-26b is implicated in breast cancer tumorigenesis is incompletely understood. This study was undertaken to evaluate the expression pattern of miR-26b and characterize its biological role in human breast cancer. METHODS: Reverse transcription-polymerase chain reaction (RT-PCR) was used to quantify the expression levels of miR-26b in breast cancer and adjacent non-cancerous breast tissues. MTT, colony formation assay and cell cycle assay were carried out to characterize the miR-26b function. Finally, to validate the target gene of miR-26b, luciferase reporter assay was employed, followed by RT-PCR and Western blot confirmation. RESULTS: Here, we found that miR-26b expression was relatively downregulated in breast cancer specimens (P<0.01). Overexpression of miR-26b dramatically suppressed cell proliferation, colony formation and induced G0/G1 cell cycle arrest of MDA-MB-231 and Mcf-7 cells. Luciferase assays revealed that miR-26b directly targeted the 3'UTR of CDK8. Overexpression of miR-26b led to the downregulation of CDK8 and β-catenin expression. Similarly, CDK8 knockdown by siRNA suppressed cell growth and subsequent β-catenin expression. CONCLUSIONS: These findings suggest that miR-26b exerts a tumor suppressive role in breast cancer and the miR-26b-mediated growth inhibition is achieved through suppression of a new target gene CDK8.
Source: Europe PMC (PubMed Central)
Authors: Jia Li, Xiaoyu Li, Xiangjie Kong, Qifeng Luo, Junfeng Zhang, Lin Fang
Institutions: Tongji University, Shanghai Tenth People's Hospital
Language: English
Subfield: Cancer Research
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W1606452383