PHF19, also known as PHD finger protein 19 or polycomb-like 3, is a crucial subunit of the Polycomb Repressive Complex 2 (PRC2) and plays a pivotal role in epigenetic regulation. It is involved in processes such as cell cycle regulation, differentiation, angiogenesis, and extracellular matrix organization [1,5]. Through its association with PRC2, PHF19 is linked to the trimethylation of histone H3 lysine 27 (H3K27me3), which is important for gene silencing and normal development [3,4,6].

In hepatocellular carcinoma (HCC), knocking out PHF19 in a MycF/F mouse model using the hydrodynamic method inhibited tumorigenesis and improved survival, demonstrating that PHF19 promotes HCC cell growth by activating the Hedgehog signaling pathway [2]. In multiple myeloma, functional knockdown of PHF19 led to decreased tumor growth in vitro and in vivo, highlighting its role in this cancer's biology [3]. In prostate cancer cells, depletion of PHF19 affected cell proliferation, invasive growth, and angiogenesis, revealing its role in balancing these processes [5].

In conclusion, PHF19 is an important epigenetic regulator involved in multiple biological processes. Model-based research, especially through gene knockout experiments in mouse models, has revealed its significant role in cancer development, particularly in hepatocellular carcinoma, multiple myeloma, and prostate cancer. Understanding PHF19's functions provides potential therapeutic targets for these diseases.