ABSTRACT
Background & objectives: Imbalances in compactly regulated DNA repair pathways in the form of single nucleotide polymorphisms (SNPs) within vital DNA repair genes may result in insufficient DNA repair and increase in DNA breaks thus rendering the human system vulnerable to the debilitatory effects of grave diseases like cancers. The present study involves investigation of association of the non-synonymous SNP rs1052133 (C8069G/Ser326Cys) located in the exonic region of the gene human 8-oxoguanine DNA glycosylase (hOGG1) with the risk of squamous cell carcinomas of the head and neck (SCCHN). Methods: Case-control based genetic association study was performed among 575 (250 SCCHN cases and 325 normal healthy controls) sub-population cluster-matched (Indo-Europeans linguistic subgroup + Caucasoid morphological subtype) samples from the north Indian States of Uttar Pradesh and Uttarakhand using polymerase chain reaction followed by restriction fragment length polymorphism (PCR-RFLP) and DNA sequencing analysis. Results: Our results demonstrated statistically significant protective association for the heterozygous CG [Odds Ratio (OR) 0.6587, 95% Confidence Interval (CI) 0.4615 to 0.9402, P=0.0238], homozygous mutant GG (OR 0.2570, 95% CI 0.1070 to 0.6175, P=0.0013) and combined mutant CG + GG (OR 0.6057, 95% CI 0.4272 to 0.8586, P=0.0059) genotypes. Interpretation & conclusions: The results indicate that the polymorphism rs1052133 is strongly associated with SCCHN susceptibility and the mutant (G) allele might be a protective factor for SCCHN among north Indian subpopulations.
Subject(s)
Carcinoma/enzymology , Carcinoma/genetics , Carcinoma/pathology , Carcinoma, Squamous Cell , Case-Control Studies , DNA Glycosylases/genetics , DNA Repair , Databases, Genetic , Genetic Predisposition to Disease , Genotype , Head and Neck Neoplasms/enzymology , Head and Neck Neoplasms/genetics , Head and Neck Neoplasms/pathology , Humans , India , Neoplasms, Squamous Cell/enzymology , Neoplasms, Squamous Cell/genetics , Neoplasms, Squamous Cell/pathology , Polymorphism, Single Nucleotide , Risk FactorsABSTRACT
OBJETIVO: Investigar o polimorfismo MTHFD1 G1958A envolvido no metabolismo do folato no risco para o câncer de cabeça e pescoço e verificar a associação entre esse polimorfismo com fatores de risco e características clínico-histopatológicas. MÉTODOS: Estudo retrospectivo que avaliou o polimorfismo MTHFD1 G1958A em 694 indivíduos (240 pacientes e 454 controles), por meio da técnica de análise de polimorfismo de comprimento de fragmento de restrição. Para análise estatística foram utilizados os testes de regressão logística múltipla e qui-quadrado. RESULTADOS: Tabagismo e idade superior a 42 anos foram preditores da doença (p < 0,05). Os genótipos MTHFD1 1958GA ou AA foram associados ao tabagismo (p = 0,04) e etilismo (p = 0,03) e estão presentes em maior proporção em tumores com estádios mais avançados (p = 0,04) e em pacientes com menor sobrevida (p = 0,03). CONCLUSÃO: A presença do polimorfismo MTHFD1 G1958A associada aos hábitos tabagista e etilista aumenta o risco para desenvolvimento de câncer de cabeça e pescoço.
OBJECTIVE: To investigate the MTHFD1 G1958A polymorphism involved in the folate metabolism as a risk for head and neck cancer, and to find the association of the polymorphism with the risk factors and clinical and histopathological characteristics. METHODS: Retrospective study investigating MTHFD1 G1958A polymorphism in 694 subjects (240 patients in the Case Group and 454 in the Control Group) by Restriction Fragment Length Polymorphism (RFLP) Analysis. Multiple logistic regression and chi-square tests were used in the statistical analysis. RESULTS: Multivariable analysis showed that smoking and age over 42 years were disease predictors (p < 0.05). MTHFD1 1958GA or AA genotypes were associated with smoking (p = 0.04) and alcoholism (p = 0.03) and were more often found in more advanced stage tumors (p = 0.04) and in patients with a shorter survival (p = 0.03). CONCLUSION: The presence of MTHFD1 G1948A polymorphism associated with smoking and alcoholism raises the head and neck cancer risk.
Subject(s)
Adult , Female , Humans , Male , Middle Aged , Head and Neck Neoplasms/genetics , Methylenetetrahydrofolate Dehydrogenase (NADP)/genetics , Neoplasm Proteins/genetics , Polymorphism, Genetic , Age Factors , Alcohol Drinking/adverse effects , Genetic Predisposition to Disease , Genotype , Head and Neck Neoplasms/enzymology , Retrospective Studies , Risk Factors , Smoking/adverse effectsABSTRACT
The functional effect of the A>G transition at position 2756 on the MTR gene (5-methyltetrahydrofolate-homocysteine methyltransferase), involved in folate metabolism, may be a risk factor for head and neck squamous cell carcinoma (HNSCC). The frequency of MTR A2756G (rs1805087) polymorphism was compared between HNSCC patients and individuals without history of neoplasias. The association of this polymorphism with clinical histopathological parameters was evaluated. A total of 705 individuals were included in the study. The polymerase chain reaction-restriction fragment length polymorphism technique was used to genotype the polymorphism. For statistical analysis, the chi-square test (univariate analysis) was used for comparisons between groups and multiple logistic regression (multivariate analysis) was used for interactions between the polymorphism and risk factors and clinical histopathological parameters. Using univariate analysis, the results did not show significant differences in allelic or genotypic distributions. Multivariable analysis showed that tobacco and alcohol consumption (P < 0.05), AG genotype (P = 0.019) and G allele (P = 0.028) may be predictors of the disease and a higher frequency of the G polymorphic allele was detected in men with HNSCC compared to male controls (P = 0.008). The analysis of polymorphism regarding clinical histopathological parameters did not show any association with the primary site, aggressiveness, lymph node involvement or extension of the tumor. In conclusion, our data provide evidence that supports an association between the polymorphism and the risk of HNSCC.
Subject(s)
Female , Humans , Male , Middle Aged , /genetics , Carcinoma, Squamous Cell/genetics , Head and Neck Neoplasms/genetics , Polymorphism, Genetic/genetics , Case-Control Studies , Carcinoma, Squamous Cell/enzymology , Gene Frequency , Genetic Predisposition to Disease , Genotype , Head and Neck Neoplasms/enzymology , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , Risk FactorsABSTRACT
Reactive oxygen species (ROS) produced as a part of cellular metabolism can interact with biological macromolecules such as DNA, proteins and lipids and interfere with their normal functions, leading to the loss of cellular viability. ROS have been implicated in many pathophysiological conditions including cancer. In the present study, the damage caused by ROS and the effect of radiation in head and neck squamous cell carcinoma (HNSCC) patients were assessed in the erythrocytes by analyzing the superoxide dismutase (SOD) and catalase (CAT) activities, and levels of total thiols (T-SH) and malondialdehyde (MDA, a marker for lipid peroxidation). Blood samples were collected before the start of treatment and after the completion of radiotherapy. Both SOD and CAT activities were decreased in untreated patients, but elevated in patients after treatment. The T-SH levels were also depleted in untreated HNSCC patients, but elevated non-significantly after radiation therapy (p>0.05). The levels of MDA showed a significant increase in both untreated patients and after radiation therapy when compared with normal subjects (p<0.05). Thus, the present study indicated that the free radical-mediated damage was aggravated in untreated HNSCC patients, but the levels of antioxidants returned to baseline or nearly so after the treatment with radiation therapy.
Subject(s)
Carcinoma, Squamous Cell/enzymology , Carcinoma, Squamous Cell/metabolism , Carcinoma, Squamous Cell/radiotherapy , Case-Control Studies , Catalase/metabolism , Free Radicals/metabolism , Head and Neck Neoplasms/enzymology , Head and Neck Neoplasms/metabolism , Head and Neck Neoplasms/radiotherapy , Humans , Male , Malondialdehyde/metabolism , Middle Aged , Oxidative Stress/radiation effects , Radiation Injuries/metabolism , Sulfhydryl Compounds/metabolism , Superoxide Dismutase/metabolismABSTRACT
A variabilidade em genes relacionados aos processos de ativação e detoxificação de carcinógenos pode interferir na suscetibilidade ao câncer. OBJETIVO: Investigar a relação entre os polimorfismos GSTT1 e GSTM1 nulos e o risco para o carcinoma espinocelular de cabeça e pescoço em indivíduos tabagistas. MATERIAL E MÉTODO: Este estudo caso-controle foi realizado na Faculdade de Medicina de São José do Rio Preto, Brasil. Foram avaliadas as freqüências dos genótipos nulos GSTT1 e GSTM1 por PCR multiplex em 60 pacientes com carcinoma espinocelular de cabeça e pescoço e 60 indivíduos sem a doença. RESULTADOS: A cavidade oral foi o sítio de tumor mais freqüente. O genótipo GSTT1 nulo foi encontrado em 33,3 por cento dos pacientes e em 23,3 por cento dos indivíduos controles (p=0,311). Os grupos caso e controle apresentaram freqüências do genótipo GSTM1 nulo de 35 por cento e 48,3 por cento, respectivamente (p=0,582). Não foram encontradas associações entre o hábito etilista e genótipos nulos GSTT1 e GSTM1 em ambos os grupos (valores de p>0,05). O gênero masculino e o hábito etilista foram prevalentes em ambos os grupos. CONCLUSÃO: Neste estudo não foi possível estabelecer uma correlação entre os genótipos nulos GSTT1 e GSTM1 e o carcinoma espinocelular de cabeça e pescoço em indivíduos tabagistas.
Gene variability related to carcinogen activation and detoxification may interfere with susceptibility to head and neck cancer. AIM: To investigate the relation between GSTT1 and GSTM1 null polymorphisms and the risk of head and neck squamous cell carcinoma in cigarette smokers. MATERIAL AND METHOD: A case-control study conducted at the Sao Jose do Rio Preto Medical School, Brazil. GSTM1 and GSTT1 null genotype frequencies were evaluated by multiplex PCR in 45 cigarette smokers with head and neck squamous cell carcinomas and 45 cigarette smokers without this disease. RESULTS: The oral cavity was the most prevalent tumor site for squamous cell carcinoma. The GSTT1 null genotype was found in 33.3 percent of the Experimental Group and 23.3 percent of the Control Group (p= 0.311). Experimental and Control Groups had GSTM1 null genotype frequencies of 35 percent and 48.3 percent (p=0.582). No association between alcohol consumption and GSTT1 and GSTMI null genotypes was found in these groups (p-values>0.05). There were more men, and alcohol consumption was prevalent in both groups. CONCLUSION: In this study we were unable to show a correlation between GSTM1 and GSTT1 genotypes and the development of head and neck squamous cell carcinomas in cigarette smokers.
Subject(s)
Humans , Male , Female , Middle Aged , Carcinoma, Squamous Cell/genetics , Glutathione Transferase/genetics , Head and Neck Neoplasms/genetics , Polymorphism, Genetic , Smoking/adverse effects , Case-Control Studies , Carcinoma, Squamous Cell/enzymology , Carcinoma, Squamous Cell/etiology , Gene Frequency , Genetic Predisposition to Disease , Genotype , Head and Neck Neoplasms/enzymology , Head and Neck Neoplasms/etiology , Risk FactorsABSTRACT
Interacões entre células neoplásicas e constituintes da matriz extracelular (MEC) interferem fortemente no desenvolvimento tumoral, incluindo os localizados em cabeca e pescoco, pois influenciam a proliferacão e sobrevivência celular, bem como a sua capacidade de migrar do sítio primário para outros tecidos e formar metástases. Essa migracão celular é facilitada pela destruicão parcial da MEC, a qual é realizada pelas metaloproteinases (MMPs), que representam uma família de mais de vinte endopeptidases, com atividade controlada pela expressão de inibidores específicos (TIMPs). Diversos estudos utilizando-se de marcadores para constituintes da MEC bem como pelas MMPs têm fornecido informacões adicionais sobre o diagnóstico e prognóstico em carcinomas de cabeca e pescoco. Nesta revisão consideraremos o papel da MEC e das MMPs na progressão desses tumores, enfatizando que não somente a degradacão proteolítica está envolvida neste processo, como também interacões entre vários constituintes da MEC fornecem substrato para regulacão e crescimento destes tumores.
Subject(s)
Humans , Carcinoma, Squamous Cell/enzymology , Extracellular Matrix Proteins/metabolism , Head and Neck Neoplasms/enzymology , Matrix Metalloproteinases/metabolism , Neoplasm Invasiveness/physiopathology , Neoplasm Metastasis/physiopathology , Carcinoma, Squamous Cell/pathology , Extracellular Matrix/metabolism , Head and Neck Neoplasms/pathology , PrognosisABSTRACT
50 patients of head and neck malignancy were selected for this study while excluding those associated with renal, hepatic, cardiac and metabolic diseases. Age and sex matched even number of controls were also included for comparison. Serum LDH levels in the control group were 124.2 +/- 3.50 I.U./L. Higher levels of LDH were observed in patients with malignancy of head and neck (335.50 +/- 21.60 I.U./L, P < 0.001). Serum LDH level was also related to histopathological stage of malignancy, being higher in poorly differentiated tumour as compared to moderate and well differentiated malignancy. Patients without metastasis had insignificantly lower serum LDH levels as compared to those with metastasis.