The Inhibitory Effect of Hsa-miR-330 Replacement on the Proliferation and Migration of Breast Cancer MCF-7 Cells

Objectives: miRNAs comprise a group of master gene expression regulators, exerting their effects after transcription through targeting specific mRNAs, hence, influencing cellular processes. A considerable number of miRNAs are known to affect cell proliferation and migration in breast cancer, one of which is hsa-miR-330, a key player in various types of cancers. The purpose of this study was to evaluate the anti-proliferative and anti-migrative effects of hsa-miR-330 on MCF-7 cell line. Materials and Methods: MCF-7 cells were transfected with pCMV-miR-330 vector and cell selection was performed in media containing Geneticin (G418). Subsequently, MTT assay was performed to evaluate the effect of hsa-miR-330 on proliferation and scratch wound healing assay was employed to evaluate cellular migration. Finally, using real-time PCR, the expression of hsa-miR-330 as well as the repressive impact on the expression of E2F was investigated. Results: Upon confirmation of hsa-miR-330 induction in MCF-7 cells via GFP channel imaging system, miR-330 expression was demonstrated to be increased 10 folds in stable cells. The results of MTT and wound-healing assays demonstrated an inhibitory role for hsa-miR-330 in proliferation and migration of stable hsa-miR-330-transfected MCF-7 cancer cells compared to controls. In addition, after transfecting cells with hsa-miR-330, E2F1 was down-regulated in comparison with controls. Conclusions: Based on the results of the current study, we suggest a potential inhibitory role for hsa-miRNA-330 in cell proliferation as well as cell migration in breast cancer by targeting E2F1 mRNA. Additionally, a therapeutic role can be suggested for hsa-miR-330 in terms of target therapy for breast cancer.