Role of Hypoxia-Associated Long Noncoding RNAs in Cancer Chemo-Therapy Resistance

Hypoxia is a well-known characteristic of the tumor microenvironment which significantly influences cancer development and is closely linked to unfavorable outcomes. Long noncoding RNAs (lncRNAs), which are part of the noncoding genome, have garnered increasing attention because of their varied functions in tumor metastasis. Long noncoding RNAs (lncRNAs) are defined as noncoding RNAs which are longer than 200 nucleotides, and they regulate diverse cellular processes by modulating gene expression at the transcriptional, post-transcriptional and epigenetic levels. Hypoxia is a well-established environmental factor which enhances the metastasis of solid tumors. Epithelial-mesenchymal transition (EMT) represents one of the key mechanisms triggered by hypoxia which contributes to metastasis. Numerous lncRNAs have been identified as being upregulated by hypoxia. These lncRNAs significantly contribute toward cancer cell migration, invasion and metastasis. Recent studies have identified a crucial role for these hypoxia-induced lncRNAs in chemotherapy resistance. These hypoxia-related lncRNAs can be plausible therapeutic targets for devising effective cancer therapies.