MicroRNAs as regulators of VEGFA and NFE2L2 in cancer

MicroRNAs (miRNAs) are small non-coding RNAs that are involved in post-transcriptional regulation of various genes, and their deregulation can lead to tumorigenesis. They may play the role of oncogenes or tumor suppressors by regulating different genes involved in cellular processes. One of the genes regulated by the miRNAs is the vascular endothelial growth factor A (VEGFA), which is responsible for angiogenesis. Angiogenesis is the process of formation of new blood vessels from pre-existing ones. This process plays an important role in tumor development, since it is responsible for the transport of nutrients required for tumor growth. Several studies have shown an increased expression of VEGFA in various cancers. Another gene regulated by miRNAs, the nuclear factor erythroid 2-like-2 (NFE2L2/NRF2), has a cytoprotective function and regulates cellular defense against oxidative stress. The NFE2L2 is the major regulator of cytoprotective agents and their oxidative damage to cells, which is down-regulated by Kelch-like ECH-associated protein 1 (KEAP1) at the post-transcriptional level. Regulation of the VEGFA and NFE2L2 by miRNAs has been observed in hepatocellular carcinoma and breast, lung, esophageal, endometrial, gastric, and ovarian cancer. This review highlights the role of miRNAs in the regulation of VEGFA and NFE2L2 and their relevance as therapeutic targets in various cancers.