title: Association between p16(CDKN2A) C540G polymorphism and tumor behavior in prolactinoma: A single-center study.
abstract: Pituitary tumors usually originate as benign sporadic adenomas and develop into invasive and aggressive tumors such as prolactinomas, which are common functioning pituitary adenomas. The aim of the present study was to examine the association between the tumor behavior in prolactinomas and the p16(CDKN2A) gene polymorphism occurring at the 3'-untranslated region of exon 3 (C540G). A total of 104 patients with prolactinoma were included and assigned to two groups based on invasive vs. non-invasive tumor behavior. Ki67 indices were recorded according to histopathology results. Genotypic analysis of the p16(CDKN2A) C540G polymorphism was carried out using a modified polymerase chain reaction-restriction fragment length polymorphism assay. The corresponding frequencies for CC, CG and GG genotypes in non-invasive vs. invasive tumors were 61.5, 30.8, 7.7 and 64.1, 28.2, 7.7%, respectively (not significant). The observed CG genotype frequency was higher compared with previous studies. In addition, the patients with giant adenomas or a high Ki67 index had a higher frequency of the CG genotype as compared with the other subgroups, although the differences were not significant (46.2 and 42.9%, respectively). In conclusion, a higher frequency of the C540G CG genotype of the CDKN2A gene was found among patients with prolactinoma in comparison with previous studies. These frequencies were also higher in the subgroups with elevated Ki67 or giant adenomas. Further studies are required to improve the definition of the role of the CG genotype in the development and progression of tumors in prolactinomas.
authors.affiliation: Department of Endocrinology and Metabolism, Uludag University Medical School, Gorukle, Bursa 16059, Turkey ; Department of Endocrinology and Metabolism, Sevket Yilmaz Education and Research Hospital, Osmangazi, Bursa 16230, Turkey.
authors.forename: Soner
authors.initials: S
authors.lastname: Cander
authors.affiliation: Department of Medical Genetic, Uludag University Medical School, Gorukle, Bursa 16059, Turkey.
authors.forename: Mutlu
authors.initials: M
authors.lastname: Karkucak
authors.affiliation: Department of Endocrinology and Metabolism, Uludag University Medical School, Gorukle, Bursa 16059, Turkey.
authors.forename: Ozen Oz
authors.initials: OO
authors.lastname: Gul
authors.affiliation: Department of Medical Genetic, Uludag University Medical School, Gorukle, Bursa 16059, Turkey.
authors.forename: Sebnem Ozemri
authors.initials: SO
authors.lastname: Sag
authors.affiliation: Department of Medical Genetic, Uludag University Medical School, Gorukle, Bursa 16059, Turkey.
authors.forename: Tahsin
authors.initials: T
authors.lastname: Yakut
authors.affiliation: Department of Endocrinology and Metabolism, Uludag University Medical School, Gorukle, Bursa 16059, Turkey.
authors.forename: Canan
authors.initials: C
authors.lastname: Ersoy
authors.affiliation: Department of Endocrinology and Metabolism, Uludag University Medical School, Gorukle, Bursa 16059, Turkey.
authors.forename: Ercan
authors.initials: E
authors.lastname: Tuncel
authors.affiliation: Department of Endocrinology and Metabolism, Uludag University Medical School, Gorukle, Bursa 16059, Turkey.
authors.forename: Erdinc
authors.initials: E
authors.lastname: Erturk
keywords: CDKN2A C540G polymorphism; invasiveness; prolactinoma; tumor behavior