Mutation Analysis of Gsa, Adrenocorticotropin Receptor p53 Genes in Japanese Patients with Adrenocortical Neoplasms: Including a Case of Gsa Mutation

While the mechanisms of tumorigenesis for adrenocortical neoplasms remain unknown, several genes, such as Gsa, ACTH receptor (MC2-R), p53, and p16 tumor suppressor genes, are considered to be candidates for adrenocortical neoplasms. Mutation analysis studies have documented these genes in adrenocortical neoplasms, but these studies focused on the mutation of only one of these genes. In the present study we examined the mutations of three of these genes (Gsa, MC2-R, and p53) in adrenocortical neoplasms in Japanese patients. We amplified these genes using polymerase chain reaction and directly sequenced them in 30 functioning adrenocortical neoplasms. As for Gsa, we identified a heterogeneous substitution of glutamine to histidine at codon 227 and a gain of an Nru 1 restriction endonuclease site. The mutation was restricted to adenomatous tissue, and did not occur in the adjacent normal adrenal tissue or leukocytes of the patient. We did not find any mutations in MC2-R and p53. In conclusion, although the contribution of these three genes to adrenocortical tumorigenesis remains to be determined, it is suggested that the mutation of Gsa might play a role in functional adrenocortical neoplasms.