Role of miRNAs as Microcontrollers Leading to Major Consequences in Breast Cancer Metastasis

Abstract

Breast cancer is one of the most common cancers occurring in women around the world. Breast cancer metastasizes mainly in four main organs of the body-Bone, Lung, Brain and Liver. There are many different subtypes of Breast cancer and one of them is Triple Negative Breast cancer (TNBC). TNBC refers to the absence of the three main receptors important in breast cancer mainly- Estrogen receptor, Progesterone receptor and Human Epidermal Growth Factor 2. As the person suffering from this type of breast cancer does not have any of the hormone receptors on the breast cancer cells, hormone therapy is not helpful in treating this cancer. miRNAs that are short and non-coding nucleotides are involved in many functions such as cell growth, differentiation, cell survival and most importantly carcinogenesis. They are deregulated (upregulated or downregulated), and this deregulation affects several genes and pathways which leads to Breast cancer. Thus, taking into consideration about the incidence of the breast cancer and miRNAs being the key regulators or microcontrollers of breast cancer, the study intended to uncover those key miRNAs playing role in Breast Cancer Metastasis and Non-Metastasis and TNBC Metastasis and Non-Metastasis and to check their expression. For wet lab experimentations two breast cancer cell lines MCF-7 (ER+, PR+) and MDA-MB-231 (ER-, PR-, HER2-) were used. For the bioinformatics approach, the data was analyzed in the GEO dataset of NCBI, further analysis was done using Venn-Diagram. Hub miRNAs were obtained using miRNet and GeneCodis 4.0 was used to find out the target pathways and genes related to the key miRNAs. This approach helped not only in gaining the knowledge of the key miRNAs playing a role in the process of metastasis and non-metastasis in Breast Cancer and TNBC, but also the key genes and pathways related to it.