H19 is a long non-coding RNA (lncRNA). It is an imprinted gene, normally expressed from the maternal allele. H19 is involved in multiple biological processes and has been associated with various diseases, especially cancers. It functions in the regulation of cell growth, proliferation, and metastasis through multiple pathways, such as the lncRNA-microRNA-messenger RNA-competitive endogenous RNA (ceRNA) network [1,2,3,4,6].

In cancer research, H19 has been shown to play oncogenic roles. In colorectal cancer, it aids in cell growth, invasion, and metastasis. Inhibition of H19 in hepatic cells can affect endoplasmic reticulum-mitochondria contact and gluconeogenesis [3,5]. In colorectal cancer, carcinoma-associated fibroblasts can promote cancer stemness and chemoresistance by transferring exosomal H19 [6]. H19 also confers chemoresistance in various cancers like breast, lung, glioma, and liver cancer through mechanisms such as induction of EMT and activation of oncogenic signaling pathways [7].

In conclusion, H19 is a significant lncRNA involved in cancer development, metastasis, and chemoresistance. Its role in cancer-related biological processes has been revealed through in-vivo studies, which provides potential therapeutic targets for cancer treatment. The understanding of H19's function helps in deciphering the molecular mechanisms of cancer and may contribute to the development of new treatment strategies [1,2,3,4,6,7,8].