title: Influence of Arg72Pro polymorphisms of TP53 on  the response of buccal cells to radiotherapy.
abstract: Polymorphisms in the TP53 gene codon 72  (Arg72Pro) influence apoptosis induction and DNA damage repair. We evaluated  how variants of protein p53 (p53Arg and p53Pro) affect cell death and DNA  damage repair by analyzing the frequencies of karyorrhexis and micronuclei.  There were significant differences in the frequency of karyorrhexis between the  three p53 genotypes (Arg/Arg, Arg/Pro, and Pro/Pro), between samples taken  before and after radiotherapy, and between patients and controls. The frequency  of micronucleated cells increased significantly after radiotherapy. There were  no significant differences in the micronucleus frequency in healthy tissues of  these patients compared to controls, or in the comparisons between the three  genotypes. We conclude that Arg72Pro polymorphism influences cell apoptotic  capacity. This is the first study investigating karyorrhexis and micronuclei,  as indicators of apoptosis after radiotherapy, and how these indicators are  influenced by the TP53 polymorphism Arg72Pro.
authors.affiliation: Departamento de Biologia Geral, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brasil.
authors.forename: L
authors.initials: L
authors.lastname: Pereira
authors.forename: M R S
authors.initials: MR
authors.lastname: Carvalho
authors.forename: C G
authors.initials: CG
authors.lastname: Fonseca
authors.forename: S S S
authors.initials: SS
authors.lastname: Lima
authors.forename: E M M
authors.initials: EM
authors.lastname: Cerqueira
authors.forename: W
authors.initials: W
authors.lastname: Jorge
authors.forename: M C L
authors.initials: MC
authors.lastname: Castro
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019943:Amino Acid Substitution / Q000235:genetics*; D016022:Case-Control Studies; D005787:Gene Frequency / Q000235:genetics; D020022:Genetic Predisposition to Disease; D018095:Germ-Line Mutation / Q000235:genetics; D006801:Humans; D048629:Micronuclei, Chromosome-Defective; D008875:Middle Aged; D009061:Mouth Mucosa / Q000473:pathology* / Q000528:radiation effects*; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D011878:Radiotherapy; D016159:Tumor Suppressor Protein p53 / Q000235:genetics*
chemical_list: D016159:Tumor Suppressor Protein p53