miRNAs and Its Regulatory Role on Autophagy in Tumor Microenvironment

Abstract

Autophagy is an intracellular catabolic process that helps in maintaining cellular homeostasis. Generally, it is involved in the recycling of unwanted proteins and damaged organelles but upon cellular stress, it helps in the survival of the cells. It is a tightly regulated process and any discrepancy in its regulation leads to the generation of many pathological abnormalities. During the early phase of cancer, it functions as a tumor suppressor whereas, at later stages, it facilitates tumor growth and helps in generating resistance to cancerous cells. Due to this functional switch of the pathway, many studies have been undertaken to find the mechanism behind its regulation in different cancer types and microRNAs (miRNAs) have been recently explored to be one of the regulatory factors. miRNAs are short non-coding RNAs that regulate the gene expression of most protein-coding genes post-transcriptionally. They control many important biological pathways including autophagic response in cancer. Their expression also gets dysregulated during different stages of cancer and thus gives a promising window of their utility as an attractive target during tumor therapy. Therefore, considering the potential of autophagy regulating miRNAs as future drug targets, this review is focused on recent advances in linking miRNAs to the regulation of autophagy pathway and their role in cancer and their implications in cancer treatment.