Tumor suppressor miRNAs in invasive ductal breast cancer

Introduction & Aim: Breast cancer is one the most important cause of cancer-related death in women worldwide. MicroRNAs (miRNAs) are small non-coding RNA that regulate gene expression. The expression of miRNAs is dysregulated in many cancers including breast cancer. The aim of this study was to assess the expression of some miRNA in invasive ductal metastatic breast cancer cell lines compared with normal one. Methods: Bioanformatic prediction was performed to find miRNAs targeting mTOR and S6K1 genes. MDA-MB-231 and MCF-10A (normal) cell lines were cultured with standard protocols and total RNA was extracted by commercial RNA extraction kit. Then, cDNA synthesis was performed and Real-Time PCR for miRNAs expression analysis was done by StepOne plus® (ABI. USA). Data were analyzed using REST 2009® (Qiagen, Germany). The expression of miRNAs were normalized with SNORD 47.P-value less than 0.05 was considered statistically significant Results: miR-96 was selected based on high-score in most bioinformatic tools. Results showed the expression of hsa-miR-96 was downregulated in MDA-MB-231 compared to MCF-10A. Reduction in expression of this miRNA was more than 200 fold (P=0.001). Conclusion: There are 2 types of miRNAs: 1) oncogenic miRNAs and 2) tumor supressor miRNAs. In cancers, the expression of oncogenic miRNAs is upregulated while tumor supressor miRNAs are downregulated. In different cancers, one miRNA can act as an oncogenic or tumor suppressor. The results of this study showed that miR-96 can be a tumor suppressor and biomarker in breast cancer. More studies are needed to identify the exact role of miR-96 in breast cancer

کلیدواژه ها:

Invasive ductal Breast cancer ، miRNA ، bioinformatics