The double-edged sword of H19 lncRNA: Insights into cancer therapy

H19 long non-coding RNA (lncRNA) has many functions in cancer. Some studies have reported that H19 acts as an oncogene and is involved in cancer progression by activating epithelial-mesenchymal transition (EMT), the cell cycle and angiogenesis via mechanisms like microRNA (miRNA) sponging - the binding to and inhibition of miRNA activity. This makes H19 lncRNA a potential target for cancer therapeutics. However, several conflicting studies have also found that H19 suppresses tumour development. In this review, we shed light on the possible reasons for these conflicting findings. We also summarise the current literature on the applications of H19 lncRNA in cancer therapy in many cancers and explore new avenues for future research. This includes the use of H19 in recombinant vectors, chemoresistance, epigenetic regulation, tumour microenvironment alteration and cancer immunotherapy. The relationship between H19 and the master tumour suppressor gene p53 is also explored. In most studies, H19 knockdown via RNA interference (RNAi) or epigenetic silencing inhibits cancer development. Thus, H19 lncRNA could be a promising target for the development of cancer therapeutics. This warrants further investigations into its translational research to improve cancer therapy outcomes.