title: Prevalence of gsp oncogene in somatotropinomas and clinically non-functioning pituitary adenomas: our experience.
abstract: The purpose of the present study is to evaluate the prevalence of the gsp oncogene in Brazilian patients harboring somatotropinomas and non-functioning pituitary adenomas (NFPA). Patients and methods Deoxyribonucleic acid was extracted from 54 somatotropinomas and 14 NFPA. Exons 8 and 9 (including codons 201 and 227, respectively) of the GNAS gene were amplified by polymerase chain reaction (PCR). The PCR products were then purified and sequenced using the same primers. Results The gsp oncogene was found in nine tumors (eight somatotropinomas). The prevalence among somatotropinomas was 15% and among NFPA was 7%. The mutation was found in codon 201 in eight tumors and in codon 227 in one tumor (a somatotropinoma). No differences were found in age, sex, GH, and IGF-I levels or tumor volume at diagnosis between gsp+ and gsp- patients. Conclusion We found a lower than expected prevalence of gsp mutations in somatotropinomas and a similar prevalence in NFPA compared to previous studies from other countries.
authors.affiliation: Serviço de Endocrinologia do Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, 555/101 Ipanema, Rio de Janeiro 22421-020, Brazil.
authors.forename: Giselle Fernandes
authors.initials: GF
authors.lastname: Taboada
authors.forename: Ana Lúcia Osório
authors.initials: AL
authors.lastname: Tabet
authors.forename: Luciana A
authors.initials: LA
authors.lastname: Naves
authors.forename: Denise Pires
authors.initials: DP
authors.lastname: de Carvalho
authors.forename: Mônica Roberto
authors.initials: MR
authors.lastname: Gadelha
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009857:Oncogenes / Q000235:genetics*; D010911:Pituitary Neoplasms / Q000098:blood supply / Q000235:genetics*; D016133:Polymerase Chain Reaction; D055815:Young Adult