title: Analysis of GSTM1 and GSTT1 polymorphisms in circulating plasma DNA of lung cancer patients.
abstract: The concentration of free circulating plasma DNA and the genetic profile of patients suffering from various types of tumors were studied in an effort to increase the understanding of the biomarkers and genetic factors involved in predisposing an individual to lung cancer (LC). The polymorphic inheritance of glutathione S-transferases (GST), which modulate the effects of various genotoxic agents, especially those derived from benzo[a]pyrene, one of the main tobacco carcinogens, has been implicated in both cancer risk and prognostics. We investigated gene polymorphisms in the blood serum of patients previously diagnosed at the Pneumology Division of the Clementino Fraga Filho University Hospital of the Federal University of Rio de Janeiro and in buccal swab samples of exfoliated oral cells obtained from a population of healthy controls. The distribution of GSTM1 and GSTT1 polymorphisms was not significantly different between LC patients and the controls, suggesting that GSTM1 and GSTT1 alone or in combination are not independent risk factors for LC. However, a close relationship between smoking status and LC was clearly demonstrated. The most significant risk for LC concerning tobacco smoking was found in the association of null genotypes for GSTM1 and GSTT1 (P < 0.0001).
authors.affiliation: IBCCF, Universidade Federal do Rio de Janeiro-UFRJ, Ilha do Fundão CCS-Bloco G, Rio de Janeiro, RJ, Brazil. rosac@biof.ufrj.br
authors.forename: Rosa Estela Caseira
authors.initials: RE
authors.lastname: Cabral
authors.forename: Adriano
authors.initials: A
authors.lastname: Caldeira-de-Araujo
authors.forename: Januario Bispo
authors.initials: JB
authors.lastname: Cabral-Neto
authors.forename: Maria da Gloria
authors.initials: Mda G
authors.lastname: Costa Carvalho
mesh_terms: D000328:Adult; D000368:Aged; D001938:Brazil; D004247:DNA / Q000097:blood*; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D005838:Genotype; D005982:Glutathione Transferase / Q000097:blood / Q000235:genetics; D006801:Humans; D008175:Lung Neoplasms / Q000097:blood / Q000201:enzymology / Q000235:genetics; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic; D055815:Young Adult
chemical_list: D004247:DNA; D005982:Glutathione Transferase; C413545:glutathione S-transferase T1