GPR152 (PGR5) is a G protein-coupled receptor that may be important for the development and maintenance of functional hearing, as mouse studies have correlated GPR152 mutations with adult-onset hearing loss. Knockout studies have indicated that loss of GPR152 also contributes to neurological dysfunction. In immunohistochemistry, GPR152 has membranous positivity in the central nervous system, such as the amygdala, cerebral cortex and thalamus, and is also found in adrenal tissue, seminiferous epithelium of the testes, lymph nodules in cortical zones (strogest in mature B-cells). It also has variable membranous positivity on tumor cells in a number of different malignancies including prostate adenocarcinoma, infiltrating carcinoma of the breast, and ovarian carcinoma. References: PLoS Biol. 2019 Apr 11;17(4):e3000194, PMID: 30973865