Dissecting the genetic heterogeneity of gastric cancer

BACKGROUND

Gastric cancer (GC) is clinically heterogenous according to location (cardia/non-cardia) and histopathology (diffuse/intestinal). We aimed to characterize the genetic risk architecture of GC according to its subtypes. Another aim was to examine whether cardia GC and oesophageal adenocarcinoma (OAC) and its precursor lesion Barrett's oesophagus (BO), which are all located at the gastro-oesophageal junction (GOJ), share polygenic risk architecture.

METHODS

We did a meta-analysis of ten European genome-wide association studies (GWAS) of GC and its subtypes. All patients had a histopathologically confirmed diagnosis of gastric adenocarcinoma. For the identification of risk genes among GWAS loci we did a transcriptome-wide association study (TWAS) and expression quantitative trait locus (eQTL) study from gastric corpus and antrum mucosa. To test whether cardia GC and OAC/BO share genetic aetiology we also used a European GWAS sample with OAC/BO.

FINDINGS

Our GWAS consisting of 5816 patients and 10,999 controls highlights the genetic heterogeneity of GC according to its subtypes. We newly identified two and replicated five GC risk loci, all of them with subtype-specific association. The gastric transcriptome data consisting of 361 corpus and 342 antrum mucosa samples revealed that an upregulated expression of MUC1, ANKRD50, PTGER4, and PSCA are plausible GC-pathomechanisms at four GWAS loci. At another risk locus, we found that the blood-group 0 exerts protective effects for non-cardia and diffuse GC, while blood-group A increases risk for both GC subtypes. Furthermore, our GWAS on cardia GC and OAC/BO (10,279 patients, 16,527 controls) showed that both cancer entities share genetic aetiology at the polygenic level and identified two new risk loci on the single-marker level.

INTERPRETATION

Our findings show that the pathophysiology of GC is genetically heterogenous according to location and histopathology. Moreover, our findings point to common molecular mechanisms underlying cardia GC and OAC/BO.

FUNDING

German Research Foundation (DFG).

Plasma miR-151-3p as a Candidate Diagnostic Biomarker for Head and Neck Cancer: A Cross-sectional Study within the INHANCE Consortium

BACKGROUND

Identification of screening tests for the detection of head and neck cancer (HNC) at an early stage is an important strategy to improving prognosis. Our objective was to identify plasma circulating miRNAs for the diagnosis of HNC (oral and laryngeal subsites), within a multicenter International Head and Neck Cancer Epidemiology consortium.

METHODS

A high-throughput screening phase with 754 miRNAs was performed in plasma samples of 88 cases and 88 controls, followed by a validation phase of the differentially expressed miRNAs, identified in the screening, in samples of 396 cases and 396 controls. Comparison of the fold changes (FC) was carried out using the Wilcoxon rank-sum test and the Dunn multiple comparison test.

RESULTS

We identified miR-151-3p (FC = 1.73, P = 0.007) as differentially expressed miRNAs in the screening and validation phase. The miR-151-3p was the only overexpressed miRNA in validation sample of patients with HNC with early stage at diagnosis (FC = 1.81, P = 0.008) and it was confirmed upregulated both in smoker early-stage cases (FC = 3.52, P = 0.024) and in nonsmoker early-stage cases (FC = 1.60, P = 0.025) compared with controls.

CONCLUSIONS

We identified miR-151-3p as an early marker of HNC. This miRNA was the only upregulated in patients at early stages of the disease, independently of the smoking status.

IMPACT

The prognosis for HNC is still poor. The discovery of a new diagnostic biomarker could lead to an earlier tumor discovery and therefore to an improvement in patient prognosis.

Mediterranean diet and the prevention of non-alcoholic fatty liver disease: results from a case-control study

OBJECTIVE

Few studies report that Mediterranean dietary (MD) pattern has a beneficial role in the progression of non-alcoholic fatty liver disease (NAFLD). Evidence on its potential effect on the onset of disease are, however, scanty. With our study, we evaluated whether MD affects the risk of NAFLD with a large case-control study performed in Italy.

PATIENTS AND METHODS

Three hundred and seventy-one cases of NAFLD and 444 controls were questioned on the demographic data and their dietary habits before diagnosis. Additionally, information about lifestyles and other related diseases, such as hypertension and diabetes mellitus were collected. The MD adherence was assessed using a pre-defined Mediterranean Diet Score (MDS). Odds ratios (OR) and 95% confidence intervals (CI) were obtained using a multiple logistic regression model.

RESULTS

A high adherence to the MD is significantly associated with decreased risk of NAFLD (OR: 0.83 95% CI: 0.71-0.98). When the different MD components were examined separately, higher legumes consumption (OR: 0.62 95% CI: 0.38-0.99) and high fish consumption (OR 0.38 95% CI: 0.17-0.85) were reported to be protective against NAFLD.

CONCLUSIONS

Our study shows that a high adherence to the MD decreases the risk of NAFLD.

Genetic susceptibility of increased intestinal permeability is associated with progressive liver disease and diabetes in patients with non-alcoholic fatty liver disease

BACKGROUND AND AIM

Increased intestinal permeability plays a key role in the pathogenesis of fat deposition in the liver. The aim of our study was to assess whether a single nucleotide polymorphism of protein tyrosine phosphatase non-receptor type 2 (PTPN2) (rs2542151 T→G), involved in intestinal permeability, may be associated with non-alcoholic fatty liver disease (NAFLD) and type 2 diabetes mellitus (T2DM).

METHODS AND RESULTS

We recruited a prospective cohort of NAFLD subjects and matched controls. Clinical data, PTPN2 genotype and laboratory data were collected for each patient. Results were stratified according to liver histology and diabetes. We enrolled 566 cases and 377 controls. PTPN2 genotype distribution did not significantly differ between patients and controls. In the entire population, patients with PTPN2 rs2542151 T→G (dominant model) have a higher prevalence of diabetes; 345 patients (60.9%) underwent liver biopsy: 198 (57.4%) had steatohepatitis and 75 (21.7%) had advanced fibrosis. At multiple logistic regression analysis PTPN2 rs2542151 T→G was associated with T2DM (OR 2.14, 95% CI 1.04-4.40, P = 0.03). Patients who underwent liver biopsy, rs2542151 T→G of PTPN2 was independently associated with severe steatosis (OR 2.00, 95% CI 1.17-3.43, p = 0.01) and severe fibrosis (OR 2.23, 95% CI 1.06-4.72, P = 0.03).

CONCLUSION

Our study shows that NAFLD patients with rs2542151 T→G of PTPN2 have a higher severity of fatty liver disease and a higher prevalence of T2DM. These results suggest that individual genetic susceptibility to intestinal permeability could play a role in liver disease progression.

Tumour stage and gender predict recurrence and second primary malignancies in head and neck cancer: a multicentre study within the INHANCE consortium

Recurrence and second primary cancer (SPC) continue to represent major obstacles to long-term survival in head and neck cancer (HNC). Our aim was to evaluate whether established demographics, lifestyle-related risk factors for HNC and clinical data are associated with recurrence and SPC in HNC. We conducted a multicentre study by using data from five studies members of the International Head and Neck Cancer Epidemiology consortium—Milan, Rome, Western Europe, Sao Paulo, and Japan, totalling 4005 HNC cases with a median age of 59 (interquartile range 52–67). Multivariate hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated for recurrence and SPC. During follow-up, 1161 (29%) patients had recurrence and 343 (8.6%) developed SPC. Advanced tumour stage was associated with increased risk of recurrence in HNC overall (HR = 1.76, 95% CI 1.41–2.19). Women with laryngeal cancer had a reduced risk of recurrence compared to men (HR = 0.39, 95% CI: 0.24–0.74). Concerning predictors of SPC, advanced age (HR = 1.02; 95% CI: 1.00–1.04) and alcohol consumption (> 1 drink per day, HR = 2.11; 95% CI: 1.13–3.94) increased the risk of SPC among patients with laryngeal cancer. Additionally, women were at higher risk of SPC, in HNC overall group (HR = 1.68; 95% CI: 1.13–2.51) and oropharyngeal cancer group (HR = 1.74; 95% CI: 1.02–2.98). Tumour stage and male gender (larynx only) were positive predictors of cancer recurrence in HNC patients. Predictors of SPC were advanced age and alcohol use among laryngeal cancer cases, and female gender for oropharyngeal and HNC overall.

Effect of alcohol dehydrogenase-1B and -7 polymorphisms on blood ethanol and acetaldehyde concentrations in healthy subjects with a history of moderate alcohol consumption

This study aims to evaluate the effect of ADH1B and ADH7 genotypes on blood acetaldehyde and ethanol levels after alcohol ingestion, and to measure the genotoxic effect of smoking and ethanol on the buccal cells, also controlling for ADH variants. We recruited healthy Italian subjects with at least a moderate history of alcohol consumption. All subjects were given an alcoholic drink of 0.4 g ethanol /kg of body weight. Blood venous samples were collected at baseline, and 30, 60, 90, and 120 minutes after ingestion. Buccal cells were collected before ethanol ingestion. Sixty subjects were enrolled in the study. Individuals with the ADH1B GG genotype had median ethanol levels of 5.0mM (IQR 3.4-7.2), and those with the ADH1B GT/TT genotype had 4.7mM (IQR 4.2-4.8). Corresponding acetaldehyde levels were 1.5μM (IQR 0.7-2.6) for ADH1B GG genotype and 1.6μM (IQR 1.5-1.7) for ADH1B CG/GG genotype. Individuals with the ADH7 CC genotype had median ethanol levels of 5.0mM (IQR 3.3-7.2), while 5.0mM (IQR 4.7-5.6) was in those with the ADH7 CG/GG genotype. Corresponding acetaldehyde levels were 1.5 μM (IQR 0.7-2.6) for ADH7 CC genotype and 1.5 μM (IQR 1.4-1.6) for ADH7 CG/GG genotypes. A non-significant increase in the frequency of karyolitic and pyknotic cells was found in the group of heavy drinkers and current smokers, when compared to the moderate drinkers and the non-smokers. Our study does not support the hypothesis that ADH1B and ADH7 genotypes affect blood ethanol and acetaldehyde concentration.

Prognostic factors in head and neck cancer: a 10-year retrospective analysis in a single-institution in Italy

This study was undertaken to evaluate the association between demographics, lifestyle habits, and clinical data and overall survival (OS), recurrence and second primary cancer (SPC) in patients with first primary head and neck cancer (HNC). We retrospectively reviewed data from 482 patients treated at the "Agostino Gemelli" Teaching Hospital, Rome, between 2002-2012 for primary HNC. Individual parameters were evaluated for association with specific outcomes such as OS, cancer recurrence and second primary cancer (SPC) appearance using hazard ratios (HR) and 95% confidence intervals (CIs). Five-year OS was 60.6% for all HNC cases, 49.0% for oral cavity, 54.8% for oropharynx, 50.0% for hypopharynx and 63.4% for larynx. Predictors of OS were older age (HR = 1.04; 95% CI: 1.02-1.05) and advanced tumour stage (HR = 2.00; 95% CI: 1.41-2.84). The risk of recurrence was associated with drinking 8-14 drinks per week (HR = 1.73; 95% CI: 1.00-2.97). The risk of developing SPC increased with advanced tumour stage (HR = 2.75; 95% CI: 1.39-5.44) and with smoking for more than 40 years (HR = 3.68; 95% CI: 1.10-12.30). OS differed among HNC sites. Increasing age was an unfavourable predictor of HNC OS. Tumour stage was a prognostic factor both for OS and for risk of developing SPC. Alcohol and tobacco consumption were prognostic factors for recurrence and SPC, respectively.

Alcohol and cigarette consumption predict mortality in patients with head and neck cancer: a pooled analysis within the International Head and Neck Cancer Epidemiology (INHANCE) Consortium

BACKGROUND

This study evaluated whether demographics, pre-diagnosis lifestyle habits and clinical data are associated with the overall survival (OS) and head and neck cancer (HNC)-specific survival in patients with HNC.

PATIENTS AND METHODS

We conducted a pooled analysis, including 4759 HNC patients from five studies within the International Head and Neck Cancer Epidemiology (INHANCE) Consortium. Cox proportional hazard ratios (HRs) and the corresponding 95% confidence intervals (CIs) were estimated including terms reported significantly associated with the survival in the univariate analysis.

RESULTS

Five-year OS was 51.4% for all HNC sites combined: 50.3% for oral cavity, 41.1% for oropharynx, 35.0% for hypopharynx and 63.9% for larynx. When we considered HNC-specific survival, 5-year survival rates were 57.4% for all HNC combined: 54.6% for oral cavity, 45.4% for oropharynx, 37.1% for hypopharynx and 72.3% for larynx. Older ages at diagnosis and advanced tumour staging were unfavourable predictors of OS and HNC-specific survival. In laryngeal cancer, low educational level was an unfavourable prognostic factor for OS (HR = 2.54, 95% CI 1.01-6.38, for high school or lower versus college graduate), and status and intensity of alcohol drinking were prognostic factors both of the OS (current drinkers HR = 1.73, 95% CI 1.16-2.58) and HNC-specific survival (current drinkers HR = 2.11, 95% CI 1.22-3.66). In oropharyngeal cancer, smoking status was an independent prognostic factors for OS. Smoking intensity (>20 cigarettes/day HR = 1.41, 95% CI 1.03-1.92) was also an independent prognostic factor for OS in patients with cancer of the oral cavity.

CONCLUSIONS

OS and HNC-specific survival differ among HNC sites. Pre-diagnosis cigarette smoking is a prognostic factor of the OS for patients with cancer of the oral cavity and oropharynx, whereas pre-diagnosis alcohol drinking is a prognostic factor of OS and HNC-specific survival for patients with cancer of the larynx. Low educational level is an unfavourable prognostic factor for OS in laryngeal cancer patients.

[Comparison of conventional culture methods and quantitative real-time PCR methods for the detection of Legionella pneumophila in water samples in a large University teaching hospital in Rome, Italy]

The aims of this study were to identify the best threshold value for the real-time PCR method in detecting the presence of Legionella pneumophila in water samples, and to evaluate the prognostic significance of negative results obtained with the molecular method. From 2011 to 2014, 77 water samples were collected from hospital wards of a large University teaching hospital in Rome (Italy) and screened for L.pneumophila by the standard culture method and by real-time PCR. The high sensitivity and negative predictive value of real-time PCR make this method suitable as a quick screening tool to exclude the presence of L. pneumophila in water samples in the hospital setting.

The effect of CYP, GST, and SULT polymorphisms and their interaction with smoking on the risk of hepatocellular carcinoma

Aim. The aim of our study was to assess whether selected single nucleotide polymorphisms of CYP1A1 and 2E1, GSTM1, GSTT1, and SULT1A1 influence susceptibility towards HCC, considering their interaction with cigarette smoking. Methods. We recruited HCC cases and controls among patients admitted to the hospital "Agostino Gemelli," from January 2005 until July 2010. Odds ratios (OR) of HCC were derived from unconditional multiple logistic regression. Gene-gene and gene-smoking interaction were quantified by computing the attributable proportion (AP) due to biological interaction. Results. The presence of any CYP2E1 (*) 5B variant allele (OR: 0.23; 95% CI: 0.06-0.71) and CYP2E1 (*) 6 variant allele (OR: 0.08; 95% CI: 0.01-0.33) was inversely related to HCC. There was a borderline increased risk among carriers of combined CYP1A1 (*) 2A and SULT1A1 variant alleles (OR: 1.67; 95% CI: 0.97-3.24). A significant biological interaction was observed between GSTT1 and smoking (AP = 0.48; 95% CI: 0.001-0.815), with an OR of 3.13 (95% CI: 1.69-5.82), and borderline significant interaction was observed for SULT1A1 and smoking (AP = 0.36; 95% CI: -0.021-0.747), with an OR of 3.05 (95% CI: 1.73-5.40). Conclusion. CYP2E1 (*) 5B and CYP2E1 (*) 6 polymorphisms have a favourable effect on the development of HCC, while polymorphisms of GSTT1 and SULT1A1 might play role in increasing the susceptibility among smokers.

[Vocational training in public health during medical school: a pilot study]

The need to integrate clinical and public health training of medical students is increasingly important. Future physicians need to be able to deal with new, complex and growing public health challenges.

MATERIALS AND METHODS

A literature search was performed through Pubmed to identify the conceptual reference framework. Meetings were carried out to identify the most appropriate modalities and priorities required for drafting the project, to identify the skills to be acquired by students, to decide on teaching formats and methods to assess student learning, to draw up the teaching schedule, to define the statistical methods to be used to assess student satisfaction, and to perform the statistical analysis of results. Training in hospital hygiene and environmental safety was carried out through presentation of a relevant case. After being divided into groups the students attended the three units (Environmental Microbiology, Environmental Xenobiotics, Genetic Epidemiology and Molecular Biology) of the Hygiene Section of a Public Health Institute. Training in Organization and Health Programming involved presentation of a set of indicators for the definition of objectives and assessment of health systems or services.

RESULTS

The literature search led to the identification of the relevant literature. With regard to student satisfaction, 96% of those who replied to the questionnaire gave an overall positive review of the training course (at least 3 on a scale from 1 to 5).

CONCLUSIONS

the overall high level of student satisfaction suggests that the proposed model may be exportable. Further developments will be the assessment of trends regarding functioning of the organizational model and perceived teaching quality.

Susceptibility to Helicobacter pylori infection: results of an epidemiological investigation among gastric cancer patients

The aim of this study was to identify the clinical, demographic, lifestyle factors and selected genetic polymorphisms that affect the susceptibility towards Helicobacter pylori (H. pylori) infection in gastric cancer patients. Histological confirmed gastric adenocarcinoma cases that underwent curative gastrectomy between 2002 and 2012 were included. Gastric biopsy samples were obtained to determine the H. pylori status, and further cagA status and vacA m and s genotypes by polymerase chain reaction. Patients were interviewed with structured questionnaires, and blood samples were collected for EPHX1, GSTM1, GSTT1, IL1B, IL1-RN, MTHFR and p53 genotyping. Proportions were compared in univariate analysis, while the relation between putative risk factors and H. pylori status and genotype were measured using logistic regression analysis. One hundred forty-nine gastric cancer patients were included, of which 78.5% were H. pylori positive. Among positive patients 50% were cagA+, 72.5% vacA m1 and 80.7% vacA s1. The presence of cagA was less frequent among vacA m1 (p = 0.031) and vacA s1 (p = 0.052) subtypes. The presence of father history for any cancer was a significant risk factor for H. pylori infection [adjusted odds ratio (OR) = 8.18, 95% confidence interval (CI) 1.04-64.55]. EPHX1 exon 3 T > C (OR = 0.35, CI 95% 0.13-0.94), IL1B-511 T > C (OR = 0.38, CI 95% 0.15-0.97) and IL1-RN VNTR (OR = 0.19, CI 95% 0.06-0.58) polymorphisms were protective towards H. pylori infection in the univariate analysis. Wine consumption was associated with higher risk of carrying the H. pylori vacA m1 virulent subtype (p = 0.034). Lastly, cardiovascular diseases were less common among cagA positive subjects (p = 0.023). Father history of any cancer is a risk factor for H. pylori infection. Polymorphisms in IL1B-511, IL1-RN and EPHX1 exon 3 genes might be protective towards H. pylori infection.

A case-control study on the effect of metabolic gene polymorphisms, nutrition, and their interaction on the risk of non-alcoholic fatty liver disease

The oxidative stress is a key issue in the etiology of non-alcoholic fatty liver disease (NAFLD). The aim of our study was to evaluate the effect of metabolic gene polymorphisms involved in the oxidative stress (GSTT1, GSTM1, SULT1A1, CYP2E1, and 1A1), lifestyle and nutrition aspects, and their interaction, on the risk of NAFLD. We enrolled 294 cases and 359 controls, and collected demographics, anthropometric, lifestyle, and nutrition data. A subgroup of NAFLD provided additional data on nutrients and on physical activity engagement. Each patient provided a blood sample for DNA extraction and genotyping. Clinical and laboratory data were collected from cases. Multivariable analysis shows a significant protective effect of age, gender, and moderate drinking habits on the risk of NAFLD, while an increased risk for greater consumption of fruit and grilled meat or fish. Significant interactions were reported between alcohol consumption, fruit intake, grilled meat and fish, and selected genetic variants. From the subgroup analysis, a moderate/high consumption of fat and/or grilled meat/fish, and a high consumption of white meat increase the risk of NAFLD. Engaging any physical activity at least 1 time/week halves the risk of NAFLD. Besides confirming the beneficial effect of moderate alcohol intake and regular physical activity, and the increased risk associated with high fruit and fat intake, for the first time, we report a detrimental effect of grilled food on NAFLD risk. An effect modification by selected gene variants increases the risk in combination with fruit and grilled food intake.

Adult height and head and neck cancer: a pooled analysis within the INHANCE Consortium

Several epidemiological studies have shown a positive association between adult height and cancer incidence. The only study conducted among women on mouth and pharynx cancer risk, however, reported an inverse association. This study aims to investigate the association between height and the risk of head and neck cancer (HNC) within a large international consortium of HNC. We analyzed pooled individual-level data from 24 case-control studies participating in the International Head and Neck Cancer Epidemiology Consortium. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated separately for men and women for associations between height and HNC risk. Educational level, tobacco smoking, and alcohol consumption were included in all regression models. Stratified analyses by HNC subsites were performed. This project included 17,666 cases and 28,198 controls. We found an inverse association between height and HNC (adjusted OR per 10 cm height = 0.91, 95% CI 0.86-0.95 for men; adjusted OR = 0.86, 95% CI 0.79-0.93 for women). In men, the estimated OR did vary by educational level, smoking status, geographic area, and control source. No differences by subsites were detected. Adult height is inversely associated with HNC risk. As height can be considered a marker of childhood illness and low energy intake, the inverse association is consistent with prior studies showing that HNC occur more frequently among deprived individuals. Further studies designed to elucidate the mechanism of such association would be warranted.

Prognostic factors and outcomes in Italian patients undergoing curative gastric cancer surgery

BACKGROUND

Survival of patients after curative surgical resection for gastric cancer (GC) remains poor, thus emphasizing the need for better definition of prognostic factors to improve the long-term course of disease.

METHODS

From 1999 to 2009, 110 patients had curative-intent gastrectomy for adenocarcinoma. Clinicopathological features, Helicobacter pylori infection, dietary habits and lifestyle, and the presence of proinflammatory gene polymorphisms were evaluated.

RESULTS

At the end of follow-up, 55 deaths had occurred, 48 of them due to GC, whereas the median overall survival (OS) and disease-free survival (DFS) were 62 and 51 months, respectively. From the Kaplan-Meier analysis and log-rank test, statistically significant differences in OS and DFS were found for tumor site (only for DFS), tumor size, lymph node metastasis ratio (NR), and tumor-node-metastasis stage, but not for age, comorbidity, H. pylori infection, cigarette smoking, and IL1B or TNFA polymorphisms. Multivariable Cox regression analysis revealed NR was an independent prognostic factor for OS and DFS. Cardia tumor and patient age 65 years or older were also independent prognostic factors for OS and DFS.

CONCLUSIONS

Tumor-related factors remain strongest predictors of survival in GC patients after surgery. Particularly, NR was an effective feature in identifying patients at high risk for adverse outcome.

Prevalence and risk factors of extrapancreatic malignancies in a large cohort of patients with intraductal papillary mucinous neoplasm (IPMN) of the pancreas

BACKGROUND

The objectives of this study are to estimate prevalence and incidence of extrapancreatic malignancies (EPMs) among intraductal papillary mucinous neoplasms (IPMNs) of the pancreas, and to identify risk factors for their occurrence.

PATIENTS AND METHODS

We conducted multicentric cohort study in Italy from January 2010 to January 2011 including 390 IPMN cases. EPMs were grouped as previous, synchronous (both prevalent) and metachronous (incident). We calculated the observed/expected (O/E) ratio of prevalent EPMs, and compared the distribution of demographic, medical history and lifestyle habits.

RESULTS

Ninety-seven EPMs were diagnosed in 92 patients (23.6%), among them 78 (80.4%) were previous, 14 (14.4%) were synchronous and 5 (5.2%) were metachronous. O/E ratios for prevalent EPMs were significantly increased for colorectal carcinoma (2.26; CI 95% 1.17-3.96), renal cell carcinoma (6.00; CI 95% 2.74-11.39) and thyroid carcinoma (5.56; CI 95% 1.80-12.96). Increased age, heavy cigarette smoking, alcohol consumption and first-degree family history of gastric cancer are significant risk factors for EPMs, while first-degree family history of colorectal carcinoma was borderline.

CONCLUSION

We report an increased prevalence of EPMs in Italian patients with IPMN, especially for colorectal carcinoma, renal cell and thyroid cancers. A systematic surveillance of IPMN cases for such cancer types would be advised.

Recreational physical activity and risk of head and neck cancer: a pooled analysis within the international head and neck cancer epidemiology (INHANCE) Consortium

Increasing evidence suggests that physical activity could prevent cancer, but scanty data is available on head and neck cancer (HNC). The aim of our study is to clarify the effect of recreational physical activity (rPA) on HNC. We analyzed data from four case-control studies, including 2,289 HNC cases and 5,580 controls. rPA was classified as: none/low (reference group), moderate and high. We calculated summary Odds Ratios (ORs) by pooling study-specific ORs. Overall, moderate rPA was associated with 22% lower risk of HNC compared to those with none or very low rPA levels [OR = 0.78, 95% Confidence Interval (95% CI): 0.66, 0.91]. Moderate rPA is associated with reduced risk of oral (OR = 0.74, 95% CI: 0.56, 0.97) and pharyngeal cancer (OR = 0.67, 95% CI: 0.53, 0.85), as well as high rPA levels (OR = 0.53, 95% CI: 0.32, 0.88 for oral cavity, OR = 0.58, 95% CI: 0.38, 0.89 for pharynx). High rPA levels, however, is associated with higher risk of laryngeal cancer (OR = 1.73, 95% CI: 1.04, 2.88). Stratified analyses showed that such inverse association between moderate rPA and HNC was more evident among males (OR = 0.75, 95% CI: 0.62, 0.90), subjects ≥45 years (OR = 0.78, 95% CI: 0.66, 0.93), and ever smokers and ever drinkers (OR = 0.72, 95% CI: 0.59, 0.88). High rPA significantly reduces HNC risk among subject ≥45 years (OR = 0.66, 95% CI: 0.48, 0.91). Promoting rPA might be inversely associated with HNC.

A genome-wide association study of upper aerodigestive tract cancers conducted within the INHANCE consortium

Genome-wide association studies (GWAS) have been successful in identifying common genetic variation involved in susceptibility to etiologically complex disease. We conducted a GWAS to identify common genetic variation involved in susceptibility to upper aero-digestive tract (UADT) cancers. Genome-wide genotyping was carried out using the Illumina HumanHap300 beadchips in 2,091 UADT cancer cases and 3,513 controls from two large European multi-centre UADT cancer studies, as well as 4,821 generic controls. The 19 top-ranked variants were investigated further in an additional 6,514 UADT cancer cases and 7,892 controls of European descent from an additional 13 UADT cancer studies participating in the INHANCE consortium. Five common variants presented evidence for significant association in the combined analysis (p ≤ 5 × 10⁻⁷). Two novel variants were identified, a 4q21 variant (rs1494961, p = 1×10⁻⁸) located near DNA repair related genes HEL308 and FAM175A (or Abraxas) and a 12q24 variant (rs4767364, p =2 × 10⁻⁸) located in an extended linkage disequilibrium region that contains multiple genes including the aldehyde dehydrogenase 2 (ALDH2) gene. Three remaining variants are located in the ADH gene cluster and were identified previously in a candidate gene study involving some of these samples. The association between these three variants and UADT cancers was independently replicated in 5,092 UADT cancer cases and 6,794 controls non-overlapping samples presented here (rs1573496-ADH7, p = 5 × 10⁻⁸); rs1229984-ADH1B, p = 7 × 10⁻⁹; and rs698-ADH1C, p = 0.02). These results implicate two variants at 4q21 and 12q24 and further highlight three ADH variants in UADT cancer susceptibility.

A case-control study on the effect of apoliprotein E genotype on head and neck cancer risk

BACKGROUND

The apolipoprotein E gene (apoE) has three major isoforms encoded by the ε2, ε3, and ε4 alleles, with the ε4 allele associated with hypercholesterolemia and the ε2 allele with the opposite effect. An inverse relationship between cholesterolemia and head and neck cancer (HNC) has been previously reported, although the relationship between apoE genotypes and HNC has not been explored to date.

METHODS

Four hundred and seventeen HNC cases and 436 hospital controls were genotyped for apoE polymorphisms. Adjusted odds ratios (ORs) and 95% confidence intervals (CI) from logistic regression were used to explore the relationship between HNC and putative risk factors. A gene-environment interaction analysis was done.

RESULTS

A borderline significant 40% decreased HNC risk (OR, 0.58; 95% CI, 0.31-1.05) was observed for individuals carrying at least one ε2 allele. Females carrying at least one ε2 allele showed a 60% risk reduction (OR, 0.43; 95% CI, 0.21-0.90) for HNC compared with ε3 homozygotes. A statistically significant interaction was found between alcohol use and the ε4 allele (P for interaction = 0.04), with a 2-fold increased risk (OR, 2.06; 95% CI, 0.95-4.48) among ever drinkers with an ε4 allele, with respect to ε3 homozygote nondrinkers.

CONCLUSIONS

Our study provides novel evidence of a possible protective effect of the ε2 allele against HNC, probably due to its increased antioxidant properties.

IMPACT

According to our results, apolipoprotein E may play a different role in carcinogenesis other than its well-known role in regulating blood serum cholesterol levels.

A case-control study on the combined effects of p53 and p73 polymorphisms on head and neck cancer risk in an Italian population

Background

The purpose of this study is to analyze the combined effects of selected p53 and p73 polymorphisms and their interaction with lifestyle habits on squamous cell carcinoma of the head and neck (SCCHN) risk and progression in an Italian population.

Methods

Two hundred and eighty-three cases and 295 hospital controls were genotyped for p53 polymorphisms on exon 4 (Arg72Pro), intron 3 and 6, and p73 G4C14-to-A4T14. Their association with SCCHN was estimated using a logistic regression analysis, while a multinomial logistic regression approach was applied to calculate the effect of the selected polymorphisms on SCCHN different sites (oral cavity, oropharynx, hypopharynx and larynx). We performed an haplotype analysis of the p53 polymorphisms, and a gene-gene interaction analysis for the combined effects of p73 G4C14-to-A4T14 and p53 polymorphisms.

Results

We found a significant increased risk of SCCHN among individuals with combined p73 exon 2 G4A and p53 intron 3 variant alleles (OR = 2.22, 95% CI: 1.08–4.56), and a protective effect for those carrying the p53 exon 4-p53 intron 6 diplotype combination (OR = 0.67; 95% CI: 0.47–0.92). From the gene-environment interaction analysis we found that individuals aged < 45 years carrying p73 exon 2 G4A variant allele have a 12.85-increased risk of SCCHN (95% CI: 2.10–78.74) compared with persons of the same age with the homozygous wild type genotype. Improved survival rate was observed among p53 intron 6 variant allele carriers (Hazard Ratio = 0.51 (95% CI: 0.23–1.16).

Conclusion

Our study provides for the first time evidence that individuals carrying p53 exon 4 and p53 intron 6 variant alleles are significantly protected against SCCHN, and also shows that an additional risk is conferred by the combination of p73 exon 2 G4C14-to-A4T14 and p53 intron 3 variant allele. Larger studies are required to confirm these findings.

Collagen-specific T-cell repertoire in blood and synovial fluid varies with disease activity in early rheumatoid arthritis

Introduction

Type II collagen is a DR4/DR1 restricted target of self-reactive T cells that sustain rheumatoid arthritis. The aim of the present study was to analyze the T-cell receptor repertoire at the onset of and at different phases in rheumatoid arthritis.

Methods

We used the CDR3 BV-BJ spectratyping to study the response to human collagen peptide 261–273 in 12 patients with DR4⁺ rheumatoid arthritis (six at the onset of disease and six during the course of disease) and in five healthy DR4⁺ relatives.

Results

The collagen-specific T-cell repertoire is quite restricted at the onset of disease, involving approximately 10 rearrangements. Within the studied collagen-specific rearrangements, nearly 75% is shared among patients. Although the size of the repertoire used by control individuals is comparable to that of patients, it is characterized by different T-cell receptors. Part of the antigen-specific T-cell repertoire is spontaneously enriched in synovial fluid. The specific T-cell repertoire in the periphery was modulated by therapy and decreased with the remission of the disease. Failure of immunoscopy to detect this repertoire was not due to suppression of collagen-driven proliferation in vitro by CD4⁺ CD25⁺ T cells. Clinical relapse of the disease was associated with the appearance of the original collagen-specific T cells.

Conclusions

The collagen-specific T-cell receptor repertoire in peripheral blood and synovial fluid is restricted to a limited number of rearrangements in rheumatoid arthritis. The majority of the repertoire is shared between patients with early rheumatoid arthritis and it is modulated by therapy.

Glutathione s-transferase gene polymorphisms in Italian patients with sudden sensorineural hearing loss

HYPOTHESIS

To investigate the association between glutathione S-transferase (GST) gene polymorphisms and sudden sensorineural hearing loss (SSNHL) in a population of consecutive Italian patients. Assuming that reactive oxygen species formation may play a role in inner ear damage, we investigated whether profiles of GSTs antioxidant enzymes M1 and T1 genotypes may be associated with the risk of SSNHL.

STUDY DESIGN

A prospective study in patients with SSNHL.

PATIENTS AND METHODS

We investigated 80 Italian patients with SSNHL for the frequency of GSTT1 and GSTM1 polymorphisms. Genotype distribution of all factors found in patients were compared with those of 80 healthy control subjects of the same ethnic background using chi and odds-ratio analysis. Statistical significance was accepted at a level of p < 0.05.

RESULTS

In our series, the frequencies of GSTM1 and GSTT1 null genotypes did not differ from those of the control subjects.

CONCLUSION

The few studies regarding genetic polymorphisms of GSTs in SSNHL are not conclusive. Further studies are needed to investigate the role of antioxidants including GSTs in SSNHL and to provide the lacking information to improve our knowledge in the field before implementing the use of genetic polymorphism in the SSNHL medicine daily practice.

Methylenetetrahydrofolate reductase C677T and A1298C polymorphisms and susceptibility to gastric adenocarcinoma in an Italian population

Methylenetetrahydrofolate reductase (MTHFR) plays a central role in the metabolism of folate, which provides a methyl donor for DNA methylation and deoxynucleoside synthesis. We performed a case-control study to explore the relationship between two common MTHFR polymorphisms (C677T and A1298C), their combination and interaction with environmental exposures, on gastric adenocarcinoma susceptibility and progression in an Italian population. One hundred and two cases and 254 hospital controls, matched by age and gender, were enrolled. Individuals carrying the MTHFR 677T allele showed an increased risk of gastric cancer (odds ratio (OR) 1.62, 95% confidence interval (CI) 0.98-2.67), particularly among ever smokers (OR 2.10, 95% CI 1.07-5.33) and, among 677 TT individuals, those with a low intake of fruit and vegetables (OR 2.18, 95% CI 1.05-4.54). The strongest effect, however, was noted for the MTHFR 677 TT genotype among the diffuse gastric cancer histotype (OR 2.92, 95% CI 1.12-7.60). No association was detected for the effect of MTHFR A1298C polymorphism. Survival analysis did not show any association between each polymorphism on the overall survival, although when the analysis was restricted to the first year of follow-up after the surgical intervention an improved survival was noted among MTHFR 677 CC subjects compared with the T allele carriers (p value for log-rank test 0.02). In conclusion, MTHFR 677 (any T genotype) appears to modulate an individual's susceptibility to gastric cancer, particularly when combined with cigarette smoking and among those with a low intake of fruit and vegetables. Our results also suggest that an aberrant DNA methylation pattern, through impaired folate metabolism, might play a key role in gastric carcinogenesis. A possible survival effect of the MTHFR C677T genotype in gastric cancer patients deserves further investigations with larger sample sizes.

Polymorphisms in metabolic genes, their combination and interaction with tobacco smoke and alcohol consumption and risk of gastric cancer: a case-control study in an Italian population

BACKGROUND

The distribution and the potential gene-gene and gene-environment interaction of selected metabolic genetic polymorphisms was investigated in relation to gastric cancer risk in an Italian population.

METHODS

One hundred and seven cases and 254 hospital controls, matched by age and gender, were genotyped for CYP1A1, CYP2E1, mEH, GSTM1, GSTT1, NAT2 and SULT1A1 polymorphisms. Haplotype analysis was performed for EPHX1 exons 3 and 4, as well as CYP2E1 RsaI (*5 alleles) and CYP2E1 DraI (*5A or *6 alleles). The effect modification by alcohol and cigarette smoking was tested with the heterogeneity test, while the attributable proportion (AP) was used to measure the biological interaction from the gene-gene interaction analysis.

RESULTS

Gastric cancer risk was found to be associated with the inheritance of GSTT1 null genotype (OR = 2.10, 95%CI: 1.27-3.44) and the SULT1A1 His/His genotype (OR = 2.46, 95%CI: 1.03-5.90). No differences were observed for the haplotype distributions among cases and controls. For the first time an increased risk was detected among individuals carrying the *6 variant allele of CYP2E1 if ever-drinkers (OR = 3.70; 95%CI: 1.45-9.37) with respect to never-drinkers (OR = 0.18; 95% CI: 0.22-1.46) (p value of heterogeneity among the two estimates = 0.001). Similarly, the effect of SULT1A1 variant genotype resulted restricted to ever-smokers, with an OR of 2.58 (95%CI: 1.27-5.25) for the carriers of His allele among smokers, and an OR of 0.86 (95%CI: 0.45-1.64) among never-smokers (p value of heterogeneity among the two estimates = 0.03). The gene-gene interaction analyses demonstrated that individuals with combined GSTT1 null and NAT2 slow acetylators had an additional increased risk of gastric cancer, with an OR of 3.00 (95%CI: 1.52-5.93) and an AP of 52%.

CONCLUSION

GSTT1, SULT1A1 and NAT2 polymorphisms appear to modulate individual's susceptibility to gastric cancer in this Italian population, particularly when more than one unfavourable genotype is present, or when combined with cigarette smoke. The increased risk for the carriers of CYP2E1*5A or *6 alleles among drinkers need to be confirmed by larger prospective studies.

CYP1A1, CYP2E1, GSTM1, GSTT1, EPHX1 exons 3 and 4, and NAT2 polymorphisms, smoking, consumption of alcohol and fruit and vegetables and risk of head and neck cancer

PURPOSE

As risk-modifiers of alcohol and tobacco effects, metabolic genes polymorphisms were investigated as susceptibility candidates for squamous cell carcinoma of the head and neck (SCCHN).

METHODS

A total of 210 cases and 245 hospital controls, age and gender matched, were genotyped for CYP1A1, CYP2E1, GSTM1, GSTT1, EPHX1 exons 3 and 4, and NAT2 polymorphisms. A measurement of the biological interaction among two risk factors was estimated by the attributable proportion (AP) due to interaction and its 95% confidence interval (CI).

RESULTS

SCCHN risk was associated with high-levels of alcohol intake [OR = 3.50 (95%CI: 1.93-6.35) and OR = 6.47 (95%CI: 2.92-14.35) for 19-30 g/day and >30 g/day, respectively], cigarette smoking [OR = 3.47 (95%CI: 1.88-6.41) and OR = 7.65 (95%CI: 4.20-13.90) for 1-25 and >25 pack-years of smoking, respectively] and low-fruit and vegetables consumption (OR = 2.45; 95%CI: 1.53-3.92). No differences were observed for the genotypes or haplotypes distributions among cases and controls, and no biological interaction emerged from gene-gene and gene-environment interaction analyses. An attributable proportion (AP) due to biological interaction of 0.65 (95%CI: 0.40-0.90) was detected for heavy drinkers with a low intake of fruit and vegetables, and an AP of 0.40 (95%CI: 0.10-0.72) resulted forever smokers with low fruit and vegetables consumption.

CONCLUSIONS

Even in presence of high alcohol consumption or cigarette smoking, a high intake of fruit and vegetables might prevent the development of around one quarter of SCCHN cases. The lack of interaction between the studied polymorphisms and the environmental exposures suggests that chronic consumption of tobacco and alcohol overwhelm enzyme defences, irrespective of genotype.

Characterization of apoptosis induced by marine natural products in non small cell lung cancer A549 cells

The effects of different marine derived agents were studied in A549 cell growth. These drugs induced cell cycle arrest at the G2-M phase associated with the up-regulation of GADD45alpha-gamma and down-regulation of c-Myc. In treated cells, GADD45alpha-gamma and c-Myc were up- and down-regulated, respectively. A cascade of events leading to apoptotic mitochondrial 'intrinsic' pathway was observed in treated cells: (1) dephosphorylation of BAD serine136; (2) BAD dissociation from 14-3-3 followed by its association with BCL-XL; (3) cytochrome c release; (4) caspase-3 activation, and (5) cleavage of vimentin. Caspase(s) inhibitor prevented the formation of cleavage products and, in turn, apoptosis was inhibited through a p53-independent mechanism. Moreover, these compounds did not activate NF-kappaB. Our findings may offer new insights into the mechanisms of action of these agents in A549 cells. The better understanding of their effects might be important to fully exploit the potential of these new drugs.

A case-control study investigating the role of sulfotransferase 1A1 polymorphism in head and neck cancer

PURPOSE

Sulfotransferases (SULT) 1A1 detoxify and bio-activate a broad spectrum of substrates including xenobiotics. The SULT1A1 gene possesses a G-->A polymorphism that results in an Arg to His substitution at codon 213, with the His allele having a low activity. The purpose of this study was to evaluate whether SULT1A1 Arg213His polymorphisms are risk factors for head and neck squamous cell carcinoma (SCCHN).

METHODS

A total of 124 consecutive primary SCCHN patients and 249 age- and sex-matched hospital controls were enrolled in this study. Genomic DNA was isolated from peripheral blood lymphocytes and genotyping was performed by PCR-RFLP. A comprehensive epidemiological interview was conducted on all participants to collect their lifestyle data.

RESULTS

The His/His frequencies in cases and controls were 6.5% (8/123) and 3.6% (9/247), respectively (P=0.049). Multivariate logistic regression analysis showed a significant association of SCCHN and His/His genotype (OR=3.60; 95% CI=1.01-12.88). This association was stronger amongst older people, alcohol and low fruit consumers. The resulted SULT1A1 His/His genotype also associated with a higher risk of neck node positive status (OR=5.82; 95% CI=1.10-30.68).

CONCLUSIONS

These preliminary findings show for the first time that the SULT1A1 His (213) allele is a possible risk factor for head and neck cancer development.

Sulfotransferase 1A1 polymorphism and gastric cancer risk: a pilot case-control study

Sulfotransferases (SULT) catalyse both the bioactivation and detoxification of a wide range of promutagens and carcinogens. The SULT1A1 gene possesses a G-->A polymorphism that results in a Arg to His substitution at codon 213, and the His allele has been shown to have a low activity and thermal stability. To test the hypothesis that individuals carrying the variant allele may be at high risk of gastric cancer, we identified the SULT1A1 Arg213His genotype by a PCR-based RFLP in a preliminary study of 76 gastric adenocarcinoma patients that underwent curative gastrectomy and 260 age and sex-matched controls from a medical centre in Rome. A comprehensive epidemiological interview was conducted on all participants to collect lifestyle data. The prognostic significance of the SULT1A1 Arg213His polymorphism with respect to staging, differentiation and histological type of gastric cancer was also evaluated. The frequencies of His/His in cases and controls were 11.9% (9/76) and 5% (13/260), respectively (P=0.025). After adjusting for substance use, age, gender and physical activity, individuals with His/His showed a 3.32 fold increased risk of developing gastric cancer compared to those with Arg/Arg (95% CI=1.17-9.45). This positive association was more pronounced amongst males, alcohol drinkers, current smokers and consumers of grilled/barbecued meat and, unexpectedly, amongst individuals with a high intake of fruit. A statistically significant association was also found between the diffuse type of gastric cancer and the heterozygous SULT1A1 genotype. Our preliminary findings suggest for the first time that the SULT1A1 His213 allele may be important in the development of gastric cancer, with other factors modulating such effect.

TNF increases camptothecin-induced apoptosis by inhibition of NF-kappaB

rHuTNF potentiates CPT-cytotoxicity in human ovarian A2780 cells. In this study, we examined the role of NF-kappaB in this potentiation. A pulse-labelled DNA study indicated that the combination CPT+TNF had little effect on the rate of DNA elongation at 6 h after drug removal, whereas CPT alone produced a complete inhibition for at least 6 h after drug removal. Flow cytometry analyses showed that CPT+TNF arrested cells in the G2-M phase, whereas CPT blocked cells in S phase. Looking at the persistence of the NF-kappaB complexes in cells, it appeared that they were still present at 24 h in TNF-treated cells. In contrast, in CPT-treated cells they persisted for 6 h. In CPT+TNF-treated cells, the NF-kappaB complexes disappeared quickly and became undetectable at 6 h. The induction of apoptosis was detected only in the CPT+TNF treated cells (using flow cytometry, a filter binding assay and ApopTag staining). These findings show that TNF, in combination with CPT, reduces the time that NF-kappaB complexes persist in cells likely resulting in the induction of apoptosis.

CCR5 and CCR2 gene polymorphisms in hypertensive patients

Essential hypertension is a complex trait under polygenic control. Evidences suggests immune system involvement during pathogenesis. CC-chemokine receptor (CCR)5 and CCR2 are characterised by gene polymorphism. Variant alleles are derived from a deletion in the CCR5 gene (CCR5delta32) and a substitution mutation at the CCR2 locus (CCR264I). CCR polymorphic forms have been studied extensively as invasion cofactors for HIV-1, but they have also been implicated in immuno-related disorders. Here, we evaluate the allelic distribution of CCR5 and CCR2 genes in essential hypertension in a case-control study. Genotype frequency in a group of essential hypertensive patients (stage I-II; n=120) and a group of unrelated, healthy Caucasian subjects (n=340) is compared. CCR gene polymorphism is analysed by polymerase chain reaction and restriction enzyme digestion. A statistically significant difference was observed for CCR5 and CCR2 mutant alleles in essential hypertensive patients, compared with the controls (P=0.004 and P=0.003, respectively). CCR5delta32 and CCR264I alleles showed a 0.096 and 0.10 frequency among cases. To date, a role for the immune system in hypertension has not been clarified, nor has the predictive value of CCR polymorphisms.

c-myc down-regulation induces apoptosis in human cancer cell lines exposed to RPR-115135 (C31H29NO4), a non-peptidomimetic farnesyltransferase inhibitor

A therapeutic strategy that relies on the use of c-myc antisense in combination with a farnesyltransferase inhibitor, RPR-115135 (C31H29NO4), was studied in human cancer cell lines carrying different mutations (Ras, p53, myc amplification). Cell proliferation was strongly inhibited by the combination and was observed when c-myc oligo (at a concentration that down-regulates c-myc expression) was followed by RPR-115135. Cell cycle analysis demonstrated an accumulation in G0-G1 phase and a tendency to apoptosis (not detectable in cells treated with a single agent). Morphological examination and DNA fragmentation assays (filter binding and enzyme-linked immunosorbent assay DNA fragmentation) confirmed the induction of apoptosis. Apoptosis was not p53- and/or p21(waf-1)-dependent, and the key effector was caspase activation. The combination induced Bax expression and Bcl-2 inhibition. Down-regulation of c-myc amplification carried out a specific role exclusively when Ras was mutated. Exposure of human proliferating lymphocytes to combination did not result in cytotoxicity, suggesting that mechanisms regulating c-myc gene expression during normal T cell proliferation might not be involved. Because of the high percentage of human tumors overexpressing c-myc mRNA and/or protein and, simultaneously, harboring oncogenic Ras mutants (i.e., colon cancers), interrupting the myc- and Ras-signaling pathway would be one of the major focuses on therapy of these types of tumors.

A molecular typing approach for evaluating bioaerosol exposure in wastewater treatment plant workers

Bioaerosols associated with wastewater treatment process may represent a health risk for occupationally exposed personnel. To evaluate microbial contamination in plant workers, we compared oral cavity isolates against isolates collected from aerosol surrounding the aeration basin. Typing was performed by metabolic profile and arbitrarily primed-polymerase chain reaction. The latter is more sensitive and rapid than conventional tests. After comparison, isolates from the air samples were not related to those obtained from the exposed workers. This molecular approach can support bioaerosol risk evaluation .

In vivo modulation of ETS genes induced by electromagnetic fields

We have previously shown that electromagnetic field (EMF) exposure induces ETS1 oncogene overexpression in different cell lines. In order to investigate in vivo EMF effects, BALB/c mice were exposed at different times to 50 MHz radiation, modulated (80%) at 16 Hz. The exposed and control animals were sacrificed and the spleen excised for rt-pcr and western blot analysis. We observed an increase in ETS1 mRNA and protein expression, but a decrease in ETS2 protein levels. Preliminary results from this experimental model show in vivo evidence of the effect of EMF on ETS oncogene expression.

Cytostatic drugs and health risks for exposed personnel: search for new biomarkers

The use of antiblastic drugs has opened up new perspectives in improvement of therapy and life quality for cancer patients. The widespread clinical application of cytostatic drugs implies risks for exposed hospital personnel, due to genotoxic and toxic-reproductive effects. Biological monitoring is fundamental to identify individuals at risk but is limited by the long latency of chronic effects, absence of unique cellular targets and low sensitivity of available laboratory tests. The objective of this study was to investigate toxic mechanisms by a molecular biology approach, searching for biomarkers potentially useful in monitoring programs. The proposed experimental model consisted of cell line exposure to cyclophosphamide, an alkylating agent of wide clinical use. Cellular response has been investigated focusing on potential targets at RNA level, through reverse transcription polymerase chain reaction (RT-PCR) and differential display analysis. We studied the expression of several genes involved in differentiation, apoptosis and chemoresistance: ets1, bax, bcl-2, bag-1, bcl-X, mdr1 and mrp. Specific patterns of mRNA modulations were observed. Differential display analysis revealed candidate genes induced or repressed following exposure: their characterization is in progress. Besides improving the understanding of toxic mechanisms, identification of modulated molecular targets opens up new perspectives in exposure risk assessment, biomonitoring and preventive strategies at occupational level.

Allelic distribution of CCR5 and CCR2 genes in an Italian population sample

Genetic polymorphisms of CCR5 and CCR2 human chemokine receptors have been associated with resistance during HIV-1 infection and disease progression. The protective effect of mutant alleles at these loci has important implications in AIDS pathogenesis. Chemokine receptors have a role in viral entry into target cells as well as in immune response modulation. In the present report, we studied the frequency of CCR5delta32 and CCR264I allelic variants among a representative sample of the Italian population. Observed allelic frequencies were 0.0454 and 0.0655, respectively. In both cases, genotype distribution was in equilibrium as predicted by the Hardy-Weinberg equation. Taken as a whole, about 21% of the population sample was found to be heterozygous for one or another of those two mutated alleles. Distribution of CCR5delta32 and CCR264I allelic variants within a population can be considered as a measure of genetic susceptibility to HIV infection and disease progression.