Identifying A Risk Profile For Thyroid Cancer.

The large use of simple and effective diagnostic tools has significantly contributed to the increase in diagnosis of thyroid cancer over the past years. However, there is compelling evidence that most micropapillary carcinomas have an indolent behavior and may never evolve into clinical cancers. Therefore, there is an urgent need for new tools able to predict which thyroid cancers will remain silent, and which thyroid cancers will present an aggressive behavior. There are a number of well-established clinical predictors of malignancy and recent studies have suggested that some of the patients laboratory data and image methods may be useful. Molecular markers have also been increasingly tested and some of them appear to be very promising, such as BRAF, a few GST genes and p53 polymorphisms. In addition, modern tools, such as immunocytochemical markers, and the measure of the fractal nature of chromatin organization may increase the specificity of the pathological diagnosis of malignancy and help ascertain the prognosis. Guidelines designed to select nodules for further evaluation, as well as new methods aimed at distinguishing carcinomas of higher aggressiveness among the usually indolent thyroid tumors are an utmost necessity.51713-2

Herpesvirus Type 7 Infection May Play An Important Role In Individuals With A Genetic Profile Of Susceptibility To Graves' Disease.

An inherited profile of genes related to the response to aggressive environmental factors such as viruses and chemicals may be related to an increased susceptibility to Graves' disease (GD). This prospective case-control study was designed to examine the relationship between human herpesviruses (HHV) infection, determined by circulating DNA; tumour protein p53 (TP53) apoptotic ability; and detoxification system genes, and GD. We studied 280 confirmed GD patients paired to 284 controls with respect to environmental exposure. Exclusion criteria included medications that could interfere with thyroid function evaluation and a recent history of viral and bacterial infections. A stepwise regression analysis adjusted for age, gender, and ethnicity established the inheritance of glutathione S-transferase pi 1 (GSTP1) (odds ratio (OR)=3.423; 95% confidence interval (CI)=2.120-5.527; P<0.001) and cytochrome P450, family 1, subfamily A, polypeptide 1 (CYP1A1) variants (OR=1.649; 95% CI=1.012-2.686; P=0.0445) as significant risk factors for the disease. HHV-7 infection was much more common in GD patients (64.64%) than in controls (38.73%; chi(2), P<0.0001), and it increased the risk for GD more than three times (OR=3.133; 95% CI=1.959-5.011; P<0.0001). The inheritance of less efficient Pro/Pro TP53 gene variants significantly increased the risk of GD development (OR=5.196; 95% CI=2.112-12.783; P<0.0001) and also favored HHV-7 infection (OR=2.835; 95% CI=1.100-7.310; P=0.0275). In addition, 72TP53 variants augmented the risk of GD relapse (OR=1.860; 95% CI=1.015-3.410; P=0.0446). We suggest that an inherited genetic profile involving TP53 may favor HHV-7 infection and maintenance, which, in turn, may initiate and perpetuate GD autoimmune process.162315-2

Lack Of Influence Of Glutathione S-transferase Genotype Profile On Cancer Susceptibility In Smokers And Nonsmokers.

The glutathione-S-transferase (GST) gene family has an important role in the biotransformation and detoxification of different xenobiotics and endogenous carcinogens. GST profile has been associated to an increased risk for several types of tumors in different populations, but ethnic stratification makes data interpretation difficult. The Brazilian population represents a unique model in which the types and frequencies of GST gene polymorphisms are less influenced by ethnicity. To evaluate the influence of GST profile in different age and gender groups regarding the risk of developing cancer and its relationship to smoking habit, the GSTT1, GSTM1, and GSTP1 genotypes of 785 Brazilian patients with cancer and 873 cancer-free controls paired on the basis of sex, age, ethnicity, diet and exercise routine, lifetime occupational history, smoking history, general health conditions, and previous diseases were compared. A univariate logistic regression analysis demonstrated that age over 45 years (p=0.0417) and smoking (p=0.0015) were related to cancer. Multivariate analysis confirmed the importance of advanced age in susceptibility to cancer (p=0.0001). It was also observed that smoking significantly increased the risk of cancer among individuals over 45 years old (OR: 1.825, 95%CI: 1.241-2.682). However, no correlation between risk of cancer, smoking habit, age, or gender and any of the studied GST polymorphisms was found. It is suggested that GST profile does not exert an important impact on the influence of tobacco smoking on cancer risk.15CR10-