Unveiling the Role of MicroRNAs in Breast Cancer Invasion

In 2018, there were significant cancer statistics indicating 8.6 million cases of female cancers and a global count of 4.2 million cancer-related deaths. Among these, breast cancer emerged as the most common malignancy in females, with approximately twenty percent of cases progressing to metastasis. Unfortunately, metastatic breast cancer poses a formidable challenge for successful treatment, necessitating the urgent identification of new molecular markers for diagnosis and prognostic prediction, as well as the development of innovative therapeutic approaches. One area of focus in breast cancer research involves differentially expressed microRNAs (miRNAs) and their role in modifying the expression of genes associated with tumor growth. These miRNAs have been extensively studied in the context of breast cancer. In this overview, we summarize recent data regarding the specific miRNA expression profiles observed in breast cancer and their involvement in regulating various invasive processes. These processes encompass changes in cytoskeletal structure, cell-cell adhesion junctions, interactions between cancer cells and the extracellular matrix, tumor microenvironments, epithelial-to-mesenchymal transitions, and the acquisition of cancer stem cell-like properties. Additionally, we explore the epigenetic regulation of individual miRNAs and their interactions with other regulatory genes. Furthermore, we examine the function of miRNA isoforms and the transfer of miRNAs through exosomes, elucidating their contribution to cancer invasiveness. While ongoing research continues to unravel the full extent of miRNA functioning in cancer, the outcomes presented here contribute to the advancement of metastatic cancer management and offer insights into potential therapeutic strategies.