Overexpression of G protein-coupled receptor 5D in the bone marrow is associated with poor prognosis in patients with multiple myeloma

Eur J Clin Invest 2012; 42 (9): 953–960 Background G protein‐coupled receptor 5D (GPRC5D) is a novel surface receptor. As this new subtype of G protein‐coupled receptors was discovered, little is known about the role of this gene. Materials and methods In this retrospective study, we investigated GPRC5D mRNA expression by real‐time polymerase chain reaction (RT‐PCR) in bone marrow (BM) of 48 patients with multiple myeloma (MM). Results Highly variable levels of GPRC5D (median, 288; quartiles, 17–928) were detected in patients with MM, whereas only low expression was detected in normal tissues (median, 1; quartiles, 1–23). High mRNA expression of GPRC5D correlated positively with high plasma cell count in bone marrow (r = 0·64, P