title: BRAF exon 15 T1799A mutation is common in melanocytic nevi, but less prevalent in cutaneous malignant melanoma, in Chinese Han.
abstract: Frequent somatic mutations of BRAF (v-raf murine sarcoma viral oncogene homolog B) exon T1799A, which are implicated in the initial events of promutagenic cellular proliferation, are detected in both malignant melanomas (MM) and melanocytic nevi (MN). Most of the data regarding BRAF exon T1799A mutation have been from Caucasian cohorts, and a comprehensive screening of a homogeneous population is lacking. A total of 379 cases of MN and 195 cases of MM were collected from Chinese Han living in three geographical regions in China, i.e., northeast, southwest, and northwest China. BRAF exon T1799A mutation was detected by PCR and sequencing from microdissected tumors. In all, 59.8% cases of MN harbored BRAF exon T1799A mutation. Samples from regions with high UV exposure had higher detection rates than regions with lower UV exposure (73.5, 67.0, and 38.9%, respectively; χ(2) = 31.674, P = 1.59E-7). There were no differences in mutation rates between congenital and acquired MN; however, acquired MN with advanced age of onset had a higher mutation rate than those with younger age of onset (χ(2) = 13.23, P = 0.02). In all, 15.0% cases of MM harbored the BRAF mutation. The mutation rate in MM was not affected by region, histological type, gender, pattern of UV exposure, and age. The study suggests that the mutation is not necessarily associated with malignant transformation.
authors.affiliation: Department of Dermatology, No 1 Hospital of China Medical University, Shenyang, Liaoning, China.
authors.forename: Rui-Qun
authors.initials: RQ
authors.lastname: Qi
authors.forename: Li
authors.initials: L
authors.lastname: He
authors.forename: Song
authors.initials: S
authors.lastname: Zheng
authors.forename: Yuxiao
authors.initials: Y
authors.lastname: Hong
authors.forename: Lei
authors.initials: L
authors.lastname: Ma
authors.forename: Shifa
authors.initials: S
authors.lastname: Zhang
authors.forename: Liping
authors.initials: L
authors.lastname: Zhao
authors.forename: Xinjian
authors.initials: X
authors.lastname: Guo
authors.forename: Yong
authors.initials: Y
authors.lastname: Wang
authors.forename: Jiang-Yun
authors.initials: JY
authors.lastname: Yu
authors.forename: Lan
authors.initials: L
authors.lastname: Fu
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.forename: Tingfeng
authors.initials: T
authors.lastname: Long
authors.forename: Chao
authors.initials: C
authors.lastname: Zhang
authors.forename: Guohong
authors.initials: G
authors.lastname: Chen
authors.forename: Junping
authors.initials: J
authors.lastname: Lin
authors.forename: Chengliang
authors.initials: C
authors.lastname: Wang
authors.forename: Li
authors.initials: L
authors.lastname: Zhou
authors.forename: Qingsheng
authors.initials: Q
authors.lastname: Mi
authors.forename: Matthew
authors.initials: M
authors.lastname: Weiland
authors.forename: John Z S
authors.initials: JZ
authors.lastname: Chen
authors.forename: S S Salum
authors.initials: SS
authors.lastname: McHenga
authors.forename: Ya-Kun
authors.initials: YK
authors.lastname: Wang
authors.forename: Uwesu
authors.initials: U
authors.lastname: McHepange
authors.forename: Zhimin
authors.initials: Z
authors.lastname: Wang
authors.forename: Hong-Duo
authors.initials: HD
authors.lastname: Chen
authors.forename: Xing-Hua
authors.initials: XH
authors.lastname: Gao
mesh_terms: D000293:Adolescent; D000328:Adult; D044466:Asian People / Q000235:genetics / Q000706:statistics & numerical data; D002648:Child; D002675:Child, Preschool; D005091:Exons / Q000235:genetics*; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008545:Melanoma / Q000453:epidemiology / Q000235:genetics*; D009154:Mutation / Q000235:genetics*; D009508:Nevus, Pigmented / Q000453:epidemiology / Q000235:genetics*; D015995:Prevalence; D048493:Proto-Oncogene Proteins B-raf / Q000235:genetics*; D012189:Retrospective Studies; D012878:Skin Neoplasms / Q000453:epidemiology / Q000235:genetics*; D014466:Ultraviolet Rays / Q000009:adverse effects; D055815:Young Adult
chemical_list: C482119:BRAF protein, human; D048493:Proto-Oncogene Proteins B-raf