title: Absence of H- and K-ras oncogene mutations in sporadic medullary thyroid carcinoma.
abstract: Medullary thyroid carcinoma (MTC) occurs sporadically (sMTC) or as part of the inherited cancer syndrome, multiple endocrine neoplasia type 2 (MEN 2). While the occurence of the MEN 2 syndrome is associated with mutations in the RET protooncogene, the reason for carcinogenesis in sMTC still remains unclear. Ras is a frequently mutated oncogene in a broad spectrum of human tumors and has been found in about 50% of follicular, papillary or anaplastic thyroid carcinomas. The purpose of this study was to determine, whether mutations in the ras oncogene could play a possible role in the carcinogenesis of sMTC. In this study we analyzed 15 sMTC for mutations in the hotspots codon 12, 13 and 61 of the H- and K-ras oncogene. We used the direct sequencing technique. In none of the examined tumors we were able to detect a mutation in the codon 12, 13 and 61 of the H-ras and K-ras oncogene. Based upon these results, we conclude that H- and K-ras do not play an important role in the carcinogenesis of sMTC.
authors.affiliation: Department of General and Transplantation Surgery, University Clinic Essen, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Bockhorn
authors.forename: A
authors.initials: A
authors.lastname: Frilling
authors.forename: V
authors.initials: V
authors.lastname: Kalinin
authors.forename: S
authors.initials: S
authors.lastname: Schröder
authors.forename: C E
authors.initials: CE
authors.lastname: Broelsch
mesh_terms: D001483:Base Sequence; D018276:Carcinoma, Medullary / Q000235:genetics*; D003062:Codon; D011905:Genes, ras / Q000235:genetics*; D006801:Humans; D009154:Mutation; D016133:Polymerase Chain Reaction; D016283:Proto-Oncogene Proteins p21(ras) / Q000235:genetics; D013964:Thyroid Neoplasms / Q000235:genetics*
chemical_list: D003062:Codon; C501009:HRAS protein, human; D016283:Proto-Oncogene Proteins p21(ras)