Anti-GPRC5A Antibody

GPRC5A, also known as retinoic acid-induced gene 3 (RAI3) or RAIG1, is a member of the orphan G-protein-coupled receptor (GPCR) family C, subgroup 5. GPRC5A is predominantly localized to the plasma membrane and intracellular compartments such as the endoplasmic reticulum and Golgi apparatus^1,2.

This protein is widely expressed in normal tissues, including the lung, liver, and kidney, and in cancers such as prostate, colon, and breast. At the cellular level, GPRC5A is found in epithelial cells and within the tumor microenvironment^1,3. It is transcriptionally regulated by retinoic acid (RA) via retinoic acid response elements in its promoter region, linking its expression to RA signaling pathways^2,4.

GPRC5A plays diverse roles in both tumor suppression and promotion, depending on the context. In lung tissue, it acts as a tumor suppressor, with its absence associated with increased lung tumor incidence in murine models². Conversely, in colon and prostate cancers, overexpression of GPRC5A is associated with poor prognosis, promoting cell proliferation and migration, and correlating with advanced disease stages and metastasis^3-5. In vitro studies demonstrate that GPRC5A enhances colony formation and cell proliferation, while its knockdown reduces these activities and induces cell cycle arrest at the G2/M phase^3-5.

Aberrant GPRC5A function has been implicated in various diseases. Its suppression in lung cancer highlights its protective role, whereas its overexpression in colon, prostate, and breast cancers indicates its involvement in tumor progression and recurrence. High cytoplasmic expression of GPRC5A in colon cancer correlates with increased recurrence risk and poor survival^2,3,5.