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Background: The polymorphic gene loci of the detoxifying enzymes GST and CYP are susceptibility factors for single head and neck cancer. In patients with multiple cancer development a cumulation of genetic risk factors can be assumed., Methods: Accordingly, we have examined genotype frequencies at GSTM1, GSTT1, GSTM3, GSTP1, CYP2D6, CYP1A1, CYP2E1, and TNF loci, in patients with single and multiple squamous cell carcinoma (SCC) of the head and neck, and controls., Results: GSTT1 0 was increased in multiple SCC patients (36.8 %) compared with single SCC patients (21.2 %) and controls (22.2 %). GSTM3 AA was more frequent in the single SCC patients (76.6 %) and multiple SCC patients (82.1 %) compared with controls (66.5 %) but lacked significance. The TNF allele B3 was significantly increased in the single SCC group (B3-allele: 22.5 %, B3/B3 : 10.8 %) and showed a further cumulation in the multiple SCC group (B3 : 30.3 %, B3/B3 : 15.8 %)., Conclusions: Patients suffering from multiple SCC development showed a cumulation of high risk genotypes at GST and TNF gene loci. Specific genetic variations could not be determined.

Background: The polymorphic gene loci of the detoxifying enzymes GST and CYP are susceptibility factors for head and neck cancer. Recently, they have been associated with outcome in several cancers., Methods: Accordingly, we have examined, in patients with squamous cell carcinoma (SCC) of the head and neck, associations between GSTM1, GSTT1, GSTM3, GSTP1, CYP2D6, CYP1A1 and CYP2E1 genotypes and outcome parameters, tumor extension, histological grade, presence of lymph nodes, and recurrence free survival over 5 years. Genotypes were determined by PCR; logistic regression and a step-wise model were used to investigate the influence of the individual genes., Results: GSTT1 0 was associated with T3/T4 tumor lesions in the pharynx and oral cavity (p = 0.029), but not laryngeal SCC cases. GSTT1 0 was also associated with histological differentiation (G3) in the oral cavity /pharynx, but not laryngeal SCC cases, although this association only approached significance (p = 0.069). CYP2D6 PM and HET were associated with lymph node involvement in the laryngeal SCC cases., Conclusions: The data demonstrate site-dependent associations between GSTT1 null and CYP2D6 PM and tumor extension and lymph node involvement in SCC of the head and neck.

Background: While cigarette smoking and alcohol consumption are risk factors for squamous cell carcinomas (SCC) of the head and neck, genetic factors are also significant. The gene of tumor necrosis factor (TNF) is located in the major histocompatibility complex class III and the cytokine has pleiotropic actions some of which are anticarcinogenic. As this gene complex is polymorphic with microsatellite markers identified it is a further candidate for head and neck cancer susceptibility., Methods: We used a case-control approach to study the influence of polymorphism at the A-D markers on susceptibility in 113 controls, 265 laryngeal and 123 oral cavity/pharyngeal SCC cases. Genotypes were identified on polyacrylamide gels in an automated DNA sequencer after amplification with fluorescently-labeled primers., Results: We found no differences in allele frequencies between controls and oral cavity/pharyngeal SCC cases but the frequency of B3 was greater in the laryngeal SCC cases than controls (p = 0.004, odds ratio 2.8). Homozygosity for B3 conferred an increased risk of laryngeal cancer compared with controls (p = 0.021, odds ratio 10.8)., Conclusions: The data provide the first evidence that allelism at MHC class III microsatellite markers is associated with risk to laryngeal SCC.

Background: While cigarette smoking and chronic alcohol consumption are the major risk factors for the development of head and neck cancer, it is assumed that genetic factors contribute to risk. Glutathione-S-transferase GSTM1 AB, GSTM3 BB and GSTP1 AA as well as TNF genotypes were determined from leucocyte DNA in 392 patients with head and neck carcinoma and 216 controls, with added immunohistochemical studies. Comparative genomic hybridization was used to screen for genetic alterations in the tumor tissue., Results: While the frequency of GSTM1 AB was significantly lower in all head and neck carcinomas compared with controls, GSTM3 BB was significantly lower in the laryngeal and GSTP1 AA in the oral cavity/pharyngeal carcinoma cases; the frequency of the TNFb3 allele was higher in the laryngeal cases. Chromosomal alterations were specific for head and neck carcinomas, differing both in well differentiated and undifferentiated and in metastasizing and non-metastasizing tumors., Conclusions: Allelism at GST gene loci mediates susceptibility to head and neck carcinomas: GSTM1 AB is associated with a lower risk for all head and neck carcinomas, GSTM3 BB only for laryngeal carcinomas and GSTP1 AA only for oral cavity/pharyngeal carcinomas. The TNFb3 allele was significantly more frequent in laryngeal cancer patients. The genetic alterations in the tumor tissue are in line with the "tumor progression model". Genetic conditions are important from the first exposure with carcinogens up to late genetic events in the tumor tissue.

Background: While cigarette smoking and chronic alcohol consumption are the major risk factors for the development of head and neck cancer, it is assumed that genetic factors contribute to risk., Material and Methods: We examined genotype frequencies from leukocyte DNA of 269 laryngeal cancer patients, 123 pharyngeal cancer patients and 216 controls. Polymorphisms at different glutathione-S-transferase (GST) gene loci were investigated. Losses of heterozygosity (LOH) at 12 different chromosomal gene loci were determined in 37 of the study patients by comparing blood and tumor cell DNA. The relationship between high risk genotypes and the occurrence of LOH was investigated., Results: Glutathione-S-transferase high risk genotypes were identified at the first and third genes of the M family (GSTM1, GSTM3) and the first gene of the P family (GSTP1). These high risk genotypes are seen to have a statistically significant influence on the occurrence of LOH in the tumor tissue., Conclusion: There is evidence that the polymorphisms studied play a role in the carcinogenic process by influencing the chromosomal fragility which may lead to the inactivation of tumor suppressor genes or the activation of oncogenes.