title: The CAG repeat polymorphism in the androgen receptor gene (AR) and its relationship to head and neck cancer.
abstract: Sex hormones may play an important role in the tumorigenic process of the head and neck. The aim of our work was to investigate whether the androgen receptor (AR) CAG repeat polymorphism is associated with an increased relative risk for head and neck cancer. Genomic DNA from 103 male patients with head and neck carcinomas and 100 male controls were analyzed for the AR CAG polymorphism by PCR amplification and direct sequencing or denaturing polyacrilamide gel electrophoresis. Logistic regression analysis showed a significant association between CAG repeat length and risk of head and neck cancer in individuals with more than 20 CAG repeats [OR=2.54 (95% CI, 1.3-4.8)]. For the group of individuals with oral and laryngeal cancer the estimated relative risk was increased to 2.79 (95% CI, 1.2-6.3) and 3.06 (95% CI, 1.0-9.6), respectively, in men with CAG repeat length >20. These results suggest, for the first time, that shorter AR CAG repeat alleles have a protective effect for head and neck cancer development.
authors.affiliation: Disciplina de Oncologia (LIM44), Departamento de Radiologia, FMUSP, Av. Dr. Arnaldo, 455, 01296-903, São Paulo, Brazil.
authors.forename: M L
authors.initials: ML
authors.lastname: dos Santos
authors.forename: T T
authors.initials: TT
authors.lastname: Sibov
authors.forename: I N
authors.initials: IN
authors.lastname: Nishimoto
authors.forename: L P
authors.initials: LP
authors.lastname: Kowalski
authors.forename: E C
authors.initials: EC
authors.lastname: Miracca
authors.forename: M A
authors.initials: MA
authors.lastname: Nagai
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000235:genetics*; D016022:Case-Control Studies; D004273:DNA, Neoplasm / Q000235:genetics; D006258:Head and Neck Neoplasms / Q000235:genetics*; D006801:Humans; D016015:Logistic Models; D008875:Middle Aged; D011110:Polymorphism, Genetic; D011944:Receptors, Androgen / Q000235:genetics*; D012091:Repetitive Sequences, Nucleic Acid
chemical_list: D004273:DNA, Neoplasm; D011944:Receptors, Androgen