G protein-coupled receptor class C group 5 member A (GPRC5A) (GPRC5A)

G protein-coupled receptor class C group 5 member A (GPRC5A), also known as Retinoic Acid-Induced Protein 3 (RAI3), is an orphan G protein-coupled receptor primarily expressed in the lung [1, 4]. It is uniquely characterized by its dual role in oncology, acting as a tumor suppressor in lung tissues while frequently being overexpressed and functioning as an oncogene in other cancers such as pancreatic, breast, and colorectal cancer [2, 3]. GPRC5A is induced by all-trans retinoic acid and plays a vital role in maintaining epithelial cell homeostasis and regulating signaling pathways including EGFR, STAT3, and NF-kappaB [1, 2]. As a therapeutic target, GPRC5A mRNA is being explored for RNA-based interventions, such as siRNA-mediated silencing in overexpressing tumors, or as a target for immunotherapy and cancer vaccines [3]. Its high expression in specific tissues makes it a potential biomarker for cancer progression and a candidate for precision medicine [4]. However, its complex role as both a suppressor and promoter of malignancy necessitates careful evaluation of the cellular context when developing GPRC5A-targeted therapies [2, 3].

Other names

Retinoic acid-induced protein 3RAI3Retinoic acid-induced gene 1 proteinRAIG1GPCR5AOrphan G protein-coupled receptor PEIG-1

Downregulation of protein expression via RNA interference (RNAi) or antisense oligonucleotides (ASOs) targeting the GPRC5A mRNA transcript [3].