GPRC5A and neoplasm: Knockdown of GPRC5A expression in mice leads to the activation of NF‐κB signalling and promotes lung inflammation and tumorigenesis.25 In colorectal cancer, GPRC5A functions as an oncogene and is abundantly present in tumour epithelium, with the neuroendocrine cells showing strong staining of GPRC5A on the plasma membrane.26 Cheng et al16 reported that GPRC5A functions as a tumour suppressor in GC.