Research Progress of GPR137 in Malignant Tumors: A Review

Receptors coupled with G proteins (GPCRs) are expressed in large numbers in multiple systems, such as endocrine, cardiovascular, digestive, immune, and reproductive systems. As an important signal transduction mediator, in recent years, the research on GPCRs has become more and more in-depth. Many articles have verified that in the gastrointestinal, reproductive, and urinary systems, GPCRs are contributed to the development and occurrence of cancerous tumors and have been associated with the infiltration of malignant tumors and metastasis. Currently, in clinical practice, GPCRs become the target of action for about 30% of drugs. However, it should be noted that there are still over 100 GPCRs collectively referred to as orphan GPCRs (OGPCRs) due to the lack of corresponding ligands. Despite the lack of known ligands, research in animals and experiments has proved that numerous OGPCRs regulate crucial physiological functions and are intriguing and undeveloped targets for therapeutics. GPR137 is a member of OGPCRS, which promotes carcinogenesis and progression of cancers, and its expression is elevated in various malignant tumor tissues. Additionally, GPR137 has been shown to play a role in promoting tumorigenesis and metastasis in colorectal, gastric, hepatocellular, ovarian and prostate cancers. Knockdown of the GPR137 leads to cell cycle arrest within cancer cells, effectively inhibiting their proliferation and colony-forming ability while promoting apoptosis. This highlights its potential therapeutic significance as a target for numerous cancers.