Prospects of GPR68 in combined chemo-immunotherapy of tumors.

GPR68 is an acid-sensitive G protein-coupled receptor (GPCR) which is also named ovarian cancer G protein-coupled receptor 1 (OGR1). The receptor regulates a range of cellular functions by responding to pH change in the extracellular environment. GPR68 is known to be highly expressed in tumor tissues and represents a promising target for tumor therapy. Furthermore, GPR68 is also highly expressed in cancer-associated fibroblasts and certain immune cells and is involved in immune regulation, which may provide a new perspective for immunotherapy. In recent years, the combination of chemotherapy and immunotherapy has become an emerging strategy for the effective treatment of cancer. This review will describe the relationship between GPR68, tumors and immunity and explore the feasibility of targeting GPR68 for therapy. Several GPR68 modulators were identified recently and will also be introduced, including agonists and specific receptor inhibitors. Finally, an outlook for GPR68-focused tumor chemo-immunotherapy will be provided.