Genetic variations in tumor-suppressor miRNA-encoding genes and their target genes: focus on breast cancer development and possible therapeutic strategies

MicroRNAs (miRNAs) negatively affect gene expression by binding to their specific mRNAs resulting in either mRNA destruction or translational repression. The aberrant expression of various miRNAs has been associated with a number of human cancer. Oncogenic or tumor-suppressor miRNAs regulate a variety of pathways involved in the development of breast cancer (BC), including cell proliferation, apoptosis, metastasis, cancer recurrence, and chemoresistance. Variations in miRNA-encoding genes and their target genes lead to dysregulated gene expression resulting in the development and progression of BC. The various therapeutic approaches to treat the disease include chemotherapy, radiation therapy, surgical removal, hormone therapy, chemotherapy, and targeted biological therapy. The purpose of the current review is to explore the genetic variations in tumor-suppressor miRNA-encoding genes and their target genes in association with the disease development and prognosis. The therapeutic interventions targeting the variants for better disease outcomes have also been discussed.