Characterization of the first definitive hematopoietic stem cells in the AGM and liver of the mouse embryo

At day 10 in mouse gestation, the intraembryonic aorta-gonads-mesonephros (AGM) region generates the first definitive hematopoietic stem cells (HSCs) of the adult blood system. By 11 days postcoitum, the liver contains such HSCs. While HSCs of the adult bone marrow and late-stage fetal liver have been extensively characterized for cell surface markers, there has been no phenotypic description of the first HSCs during embryo development. We report here the temporal cell surface phenotype of HSCs from the AGM region and early fetal liver and show that all HSCs reside in the c-kit+ population. c-kit+ HSCs from AGM and liver are mainly CD34+ and in the AGM are in both Mac-1+ and Mac-1 fractions. These results demonstrate that during mouse ontogeny the first definitive HSCs are similar in cell surface phenotype to the HSCs of adult bone marrow but that spatial localization and developmental time are critical factors in the phenotypic assessment of this functional cell population.

Evaluation of human papillomavirus antibodies and risk of subsequent head and neck cancer

PURPOSE

Human papillomavirus type 16 (HPV16) infection is causing an increasing number of oropharyngeal cancers in the United States and Europe. The aim of our study was to investigate whether HPV antibodies are associated with head and neck cancer risk when measured in prediagnostic sera.

METHODS

We identified 638 participants with incident head and neck cancers (patients; 180 oral cancers, 135 oropharynx cancers, and 247 hypopharynx/larynx cancers) and 300 patients with esophageal cancers as well as 1,599 comparable controls from within the European Prospective Investigation Into Cancer and Nutrition cohort. Prediagnostic plasma samples from patients (collected, on average, 6 years before diagnosis) and control participants were analyzed for antibodies against multiple proteins of HPV16 as well as HPV6, HPV11, HPV18, HPV31, HPV33, HPV45, and HPV52. Odds ratios (ORs) of cancer and 95% CIs were calculated, adjusting for potential confounders. All-cause mortality was evaluated among patients using Cox proportional hazards regression.

RESULTS

HPV16 E6 seropositivity was present in prediagnostic samples for 34.8% of patients with oropharyngeal cancer and 0.6% of controls (OR, 274; 95% CI, 110 to 681) but was not associated with other cancer sites. The increased risk of oropharyngeal cancer among HPV16 E6 seropositive participants was independent of time between blood collection and diagnosis and was observed more than 10 years before diagnosis. The all-cause mortality ratio among patients with oropharyngeal cancer was 0.30 (95% CI, 0.13 to 0.67), for patients who were HPV16 E6 seropositive compared with seronegative.

CONCLUSION

HPV16 E6 seropositivity was present more than 10 years before diagnosis of oropharyngeal cancers.

Identification of a common T/natural killer cell progenitor in human fetal thymus

The phenotypic similarities between natural killer (NK) and T cells have led to the hypothesis that these distinctive lymphocyte subsets may be developmentally related and thus may share a common progenitor (Lanier, L. L., H. Spits, and J. H. Phillips, 1992. Immunol. Today. 13:392; Rodewald, H.-R., P. Moingeon, J. L. Lurich, C. Dosiou, P. Lopez, and E. L. Reinherz. 1992. Cell. 69:139). In this report, we have investigated the potential of human CD34+ triple negative thymocytes ([TN] CD3-, CD4-, CD8-) to generate both T cells and NK cells in murine fetal thymic organ cultures (mFTOC) and in vitro clonogenic assays. CD34+ TN thymocytes, the majority of which express prominent cytoplasmic CD3 epsilon (cytoCD3 epsilon) protein, can be divided into high (CD34Bright) and low (CD34Dim) surface expressing populations. CD34Bright TN thymocytes were capable of differentiating into T and NK cells when transferred into mFTOC, and demonstrated high NK cell clonogenic capabilities when cultured in interleukin (IL)-2, IL-7, and stem cell factor (SCF). Likewise, CD34Bright TN thymocyte clones after 5 d in culture were capable of generating NK and T cells when transferred into mFTOC but demonstrated clonogenic NK cell differentiation capabilities when maintained in culture with IL-2. CD34Dim TN thymocytes, however, possessed only T cell differentiation capabilities in mFTOC but were not expandable in clonogenic conditions containing IL-2, IL-7, and SCF. No significant differentiation of other cell lineage was detected in either mFTOC or in clonogenic assays from CD34+ TN thymocytes. These results represent the first definitive evidence of a common T/NK cell progenitor in the human fetal thymus and delineate the point in thymocyte differentiation where T and NK cells diverge.

The link between family history and risk of type 2 diabetes is not explained by anthropometric, lifestyle or genetic risk factors: the EPIC-InterAct study

AIMS/HYPOTHESIS

Although a family history of type 2 diabetes is a strong risk factor for the disease, the factors mediating this excess risk are poorly understood. In the InterAct case-cohort study, we investigated the association between a family history of diabetes among different family members and the incidence of type 2 diabetes, as well as the extent to which genetic, anthropometric and lifestyle risk factors mediated this association.

METHODS

A total of 13,869 individuals (including 6,168 incident cases of type 2 diabetes) had family history data available, and 6,887 individuals had complete data on all mediators. Country-specific Prentice-weighted Cox models were fitted within country, and HRs were combined using random effects meta-analysis. Lifestyle and anthropometric measurements were performed at baseline, and a genetic risk score comprising 35 polymorphisms associated with type 2 diabetes was created.

RESULTS

A family history of type 2 diabetes was associated with a higher incidence of the condition (HR 2.72, 95% CI 2.48, 2.99). Adjustment for established risk factors including BMI and waist circumference only modestly attenuated this association (HR 2.44, 95% CI 2.03, 2.95); the genetic score alone explained only 2% of the family history-associated risk of type 2 diabetes. The greatest risk of type 2 diabetes was observed in those with a biparental history of type 2 diabetes (HR 5.14, 95% CI 3.74, 7.07) and those whose parents had been diagnosed with diabetes at a younger age (<50 years; HR 4.69, 95% CI 3.35, 6.58), an effect largely confined to a maternal family history.

CONCLUSIONS/INTERPRETATION

Prominent lifestyle, anthropometric and genetic risk factors explained only a marginal proportion of the excess risk associated with family history, highlighting the fact that family history remains a strong, independent and easily assessed risk factor for type 2 diabetes. Discovering factors that will explain the association of family history with type 2 diabetes risk will provide important insight into the aetiology of type 2 diabetes.

Consumption of sweet beverages and type 2 diabetes incidence in European adults: results from EPIC-InterAct

AIMS/HYPOTHESIS

Consumption of sugar-sweetened beverages has been shown, largely in American populations, to increase type 2 diabetes incidence. We aimed to evaluate the association of consumption of sweet beverages (juices and nectars, sugar-sweetened soft drinks and artificially sweetened soft drinks) with type 2 diabetes incidence in European adults.

METHODS

We established a case-cohort study including 12,403 incident type 2 diabetes cases and a stratified subcohort of 16,154 participants selected from eight European cohorts participating in the European Prospective Investigation into Cancer and Nutrition (EPIC) study. After exclusions, the final sample size included 11,684 incident cases and a subcohort of 15,374 participants. Cox proportional hazards regression models (modified for the case-cohort design) and random-effects meta-analyses were used to estimate the association between sweet beverage consumption (obtained from validated dietary questionnaires) and type 2 diabetes incidence.

RESULTS

In adjusted models, one 336 g (12 oz) daily increment in sugar-sweetened and artificially sweetened soft drink consumption was associated with HRs for type 2 diabetes of 1.22 (95% CI 1.09, 1.38) and 1.52 (95% CI 1.26, 1.83), respectively. After further adjustment for energy intake and BMI, the association of sugar-sweetened soft drinks with type 2 diabetes persisted (HR 1.18, 95% CI 1.06, 1.32), but the association of artificially sweetened soft drinks became statistically not significant (HR 1.11, 95% CI 0.95, 1.31). Juice and nectar consumption was not associated with type 2 diabetes incidence.

CONCLUSIONS/INTERPRETATION

This study corroborates the association between increased incidence of type 2 diabetes and high consumption of sugar-sweetened soft drinks in European adults.

The role of type of tobacco and type of alcoholic beverage in oral carcinogenesis

Incidence rates of oral and oropharyngeal cancers (oral cancer) in Spain are among the highest in Europe. Spain has a population heavily exposed to various types of tobacco and alcoholic beverages but the role and impact of tobacco type and beverage type in oral carcinogenesis remain controversial. To estimate the independent and joint effects of tobacco smoking and alcohol drinking habits on the risk of developing oral cancer, we carried out a multicenter, hospital-based, case-control study in Spain. Data from 375 patients newly diagnosed with cancer of the oral cavity or oropharynx and 375 matched control subjects were analyzed using multivariate logistic regression procedures. All exposure characteristics of amount, duration and cessation of both tobacco smoking and alcohol drinking were strongly associated with cancer risk following a dose-dependent relationship. At equal intake or duration levels, black-tobacco smoking and drinking of spirits were both associated with a 2- to 4-fold increase in cancer risk compared to blond tobacco smoking or drinking of wine or beer, respectively. While ever exposure to smoking only or drinking only was associated with a moderate and nonsignificant increase in cancer risk, a history of simultaneous exposure to both habits was associated with a 13-fold increase that was compatible with a synergistic effect model (p-value for interaction: 0.008). Exposure to black tobacco smoking and/or drinking of spirits may account for up to 77% of oral cancer occurrence in Spain. Both black tobacco smoking and drinking of spirits place individuals at a very high risk of developing oral cancer. Simultaneous exposure to tobacco and alcohol consumption increases oral cancer risk in a synergistic fashion, even when consumption levels are moderate. These results underline the importance of type of tobacco and alcohol concentration in oral carcinogenesis.

Design and cohort description of the InterAct Project: an examination of the interaction of genetic and lifestyle factors on the incidence of type 2 diabetes in the EPIC Study

AIMS/HYPOTHESIS

Studying gene-lifestyle interaction may help to identify lifestyle factors that modify genetic susceptibility and uncover genetic loci exerting important subgroup effects. Adequately powered studies with prospective, unbiased, standardised assessment of key behavioural factors for gene-lifestyle studies are lacking. This case-cohort study aims to investigate how genetic and potentially modifiable lifestyle and behavioural factors, particularly diet and physical activity, interact in their influence on the risk of developing type 2 diabetes.

METHODS

Incident cases of type 2 diabetes occurring in European Prospective Investigation into Cancer and Nutrition (EPIC) cohorts between 1991 and 2007 from eight of the ten EPIC countries were ascertained and verified. Prentice-weighted Cox regression and random-effects meta-analyses were used to investigate differences in diabetes incidence by age and sex.

RESULTS

A total of 12,403 verified incident cases of type 2 diabetes occurred during 3.99 million person-years of follow-up of 340,234 EPIC participants eligible for InterAct. We defined a centre-stratified subcohort of 16,154 individuals for comparative analyses. Individuals with incident diabetes who were randomly selected into the subcohort (n = 778) were included as cases in the analyses. All prevalent diabetes cases were excluded from the study. InterAct cases were followed-up for an average of 6.9 years; 49.7% were men. Mean baseline age and age at diagnosis were 55.6 and 62.5 years, mean BMI and waist circumference values were 29.4 kg/m(2) and 102.7 cm in men, and 30.1 kg/m(2) and 92.8 cm in women, respectively. Risk of type 2 diabetes increased linearly with age, with an overall HR of 1.56 (95% CI 1.48-1.64) for a 10 year age difference, adjusted for sex. A male excess in the risk of incident diabetes was consistently observed across all countries, with a pooled HR of 1.51 (95% CI 1.39-1.64), adjusted for age.

CONCLUSIONS/INTERPRETATION

InterAct is a large, well-powered, prospective study that will inform our understanding of the interplay between genes and lifestyle factors on the risk of type 2 diabetes development.

Cancer incidence in Spain, 2015

PURPOSE

Periodic cancer incidence estimates of Spain from all existing population-based cancer registries at any given time are required. The objective of this study was to present the current situation of cancer incidence in Spain.

METHODS

The Spanish Network of Cancer Registries (REDECAN) estimated the numbers of new cancer cases occurred in Spain in 2015 by applying the incidence-mortality ratios method. In the calculus, incidence data from population-based cancer registries and mortality data of all Spain were used.

RESULTS

In 2015, nearly a quarter of a million new invasive cancer cases were diagnosed in Spain, almost 149,000 in men (60.0%) and 99,000 in women. Globally, the five most common cancers were those of colon-rectum, prostate, lung, breast and urinary bladder. By gender, the four most common cancers in men were those of prostate (22.4%), colon-rectum (16.6%), lung (15.1%) and urinary bladder (11.7%). In women, the most common ones were those of breast (28.0%), colon-rectum (16.9%), corpus uteri (6.2%) and lung (6.0%). In recent years, cancer incidence in men seems to have stabilized due to the fact that the decrease in tobacco-related cancers compensates for the increase in other types of cancer like those of colon and prostate. In women, despite the stabilization of breast cancer incidence, increased incidence is due, above all, to the rise of colorectal and tobacco-related cancers.

CONCLUSION

To reduce these incident cancer cases, improvement of smoking control policies and extension of colorectal cancer screening should be the two priorities in cancer prevention for the next years.

Association between dietary meat consumption and incident type 2 diabetes: the EPIC-InterAct study

AIMS/HYPOTHESIS

A diet rich in meat has been reported to contribute to the risk of type 2 diabetes. The present study aims to investigate the association between meat consumption and incident type 2 diabetes in the EPIC-InterAct study, a large prospective case-cohort study nested within the European Prospective Investigation into Cancer and Nutrition (EPIC) study.

METHODS

During 11.7 years of follow-up, 12,403 incident cases of type 2 diabetes were identified among 340,234 adults from eight European countries. A centre-stratified random subsample of 16,835 individuals was selected in order to perform a case-cohort design. Prentice-weighted Cox regression analyses were used to estimate HR and 95% CI for incident diabetes according to meat consumption.

RESULTS

Overall, multivariate analyses showed significant positive associations with incident type 2 diabetes for increasing consumption of total meat (50 g increments: HR 1.08; 95% CI 1.05, 1.12), red meat (HR 1.08; 95% CI 1.03, 1.13) and processed meat (HR 1.12; 95% CI 1.05, 1.19), and a borderline positive association with meat iron intake. Effect modifications by sex and class of BMI were observed. In men, the results of the overall analyses were confirmed. In women, the association with total and red meat persisted, although attenuated, while an association with poultry consumption also emerged (HR 1.20; 95% CI 1.07, 1.34). These associations were not evident among obese participants.

CONCLUSIONS/INTERPRETATION

This prospective study confirms a positive association between high consumption of total and red meat and incident type 2 diabetes in a large cohort of European adults.

Fruit and vegetable consumption and mortality: European prospective investigation into cancer and nutrition

In this study, the relation between fruit and vegetable consumption and mortality was investigated within the European Prospective Investigation Into Cancer and Nutrition. Survival analyses were performed, including 451,151 participants from 10 European countries, recruited between 1992 and 2000 and followed until 2010. Hazard ratios, rate advancement periods, and preventable proportions to respectively compare risk of death between quartiles of consumption, to estimate the period by which the risk of death was postponed among high consumers, and to estimate proportions of deaths that could be prevented if all participants would shift their consumption 1 quartile upward. Consumption of fruits and vegetables was inversely associated with all-cause mortality (for the highest quartile, hazard ratio = 0.90, 95% confidence interval (CI): 0.86, 0.94), with a rate advancement period of 1.12 years (95% CI: 0.70, 1.54), and with a preventable proportion of 2.95%. This association was driven mainly by cardiovascular disease mortality (for the highest quartile, hazard ratio = 0.85, 95% CI: 0.77, 0.93). Stronger inverse associations were observed for participants with high alcohol consumption or high body mass index and suggested in smokers. Inverse associations were stronger for raw than for cooked vegetable consumption. These results support the evidence that fruit and vegetable consumption is associated with a lower risk of death.

Prediagnostic 25-hydroxyvitamin D, VDR and CASR polymorphisms, and survival in patients with colorectal cancer in western European ppulations

BACKGROUND

Individuals with higher blood 25-hydroxyvitamin D [25(OH)D] levels have a lower risk of developing colorectal cancer (CRC), but the influence of 25(OH)D on mortality after CRC diagnosis is unknown.

METHODS

The association between prediagnostic 25(OH)D levels and CRC-specific (N = 444) and overall mortality (N = 541) was prospectively examined among 1,202 participants diagnosed with CRC between 1992 and 2003 in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Multivariable Cox proportional hazards models were used to calculate HRs and corresponding 95% CIs according to 25(OH)D quintiles and genetic variation within the VDR and CASR genes. Potential dietary, lifestyle, and metabolic effect modifiers were also investigated.

RESULTS

There were 541 deaths, 444 (82%) due to CRC. Mean follow-up was 73 months. In multivariable analysis, higher 25(OH)D levels were associated with a statistically significant reduction in CRC-specific (P(trend) = 0.04) and overall mortality (P(trend) = 0.01). Participants with 25(OH)D levels in the highest quintile had an adjusted HR of 0.69 (95% CI: 0.50-0.93) for CRC-specific mortality and 0.67 (95% CI: 0.50-0.88) for overall mortality, compared with the lowest quintile. Except for a possible interaction by prediagnostic dietary calcium intake (P(interaction) = 0.01), no other potential modifying factors related to CRC survival were noted. The VDR (FokI and BsmI) and CASR (rs1801725) genotypes were not associated with survival.

CONCLUSIONS

High prediagnostic 25(OH)D levels are associated with improved survival of patients with CRC.

IMPACT

Our findings may stimulate further research directed at investigating the effects of blood vitamin D levels before, at, and after CRC diagnosis on outcomes in CRC patients.

Reproductive factors and exogenous hormone use in relation to risk of glioma and meningioma in a large European cohort study

BACKGROUND

The etiologies of glioma and meningioma tumors are largely unknown. Although reproductive hormones are thought to influence the risk of these tumors, epidemiologic data are not supportive of this hypothesis; however, few cohort studies have published on this topic. We examined the relation between reproductive factors and the risk of glioma and meningioma among women in the European Prospective Investigation into Cancer and Nutrition (EPIC).

METHODS

After a mean of 8.4 years of follow-up, 193 glioma and 194 meningioma cases were identified among 276,212 women. Information on reproductive factors and hormone use was collected at baseline. Cox proportional hazard regression was used to determine hazard ratios (HR) and 95% confidence intervals (95% CI).

RESULTS

No associations were observed between glioma or meningioma risk and reproductive factors, including age at menarche, parity, age at first birth, menopausal status, and age at menopause. A higher risk of meningioma was observed among postmenopausal women who were current users of hormone replacement therapy (HR, 1.79; 95% CI, 1.18-2.71) compared with never users. Similarly, current users of oral contraceptives were at higher risk of meningioma than never users (HR, 3.61; 95% CI, 1.75-7.46).

CONCLUSION

Our results do not support a role for estrogens and glioma risk. Use of exogenous hormones, especially current use, seems to increase meningioma risk. However, these findings could be due to diagnostic bias and require confirmation.

IMPACT

Elucidating the role of hormones in brain tumor development has important implications and needs to be further examined using biological measurements.

Diabetes mellitus, insulin treatment, diabetes duration, and risk of biliary tract cancer and hepatocellular carcinoma in a European cohort

BACKGROUND

Evidence on associations between self-reported diabetes mellitus, diabetes duration, age at diabetes diagnosis, insulin treatment, and risk of biliary tract cancer (BTC) and hepatocellular carcinoma (HCC), independent of general and abdominal obesity is scarce.

PATIENTS AND METHODS

We conducted a prospective analysis in the EPIC-cohort study among 363 426 participants with self-reported diabetes data. Multivariable adjusted relative risks and 95% confidence intervals were estimated from Cox regression models. In a nested case-control subset, analyses were carried out in HCV/HBV-negative individuals.

RESULTS

During 8.5 years of follow-up, 204 BTC cases [including 75 gallbladder cancer (GBC) cases], and 176 HCC cases were identified. Independent of body mass index and waist-to-height ratio diabetes status was associated with higher risk of BTC and HCC [1.77 (1.00-3.13) and 2.17 (1.36-3.47)]. For BTC, the risk seemed to be higher in participants with shorter diabetes duration and those not treated with insulin. Regarding cancer subsites, diabetes was only associated with GBC [2.72 (1.17-6.31)]. The risk for HCC was particularly higher in participants treated with insulin. The results were not appreciably different in HCV/HBV-negative individuals.

CONCLUSION(S)

This study supports the hypothesis that diabetes is a risk factor for BTC (particularly GBC) and HCC. Further research is required to establish whether diabetes treatment or duration is associated with these cancers.

Glycemic index, glycemic load, dietary carbohydrate, and dietary fiber intake and risk of liver and biliary tract cancers in Western Europeans

BACKGROUND

The type and quantity of dietary carbohydrate as quantified by glycemic index (GI) and glycemic load (GL), and dietary fiber may influence the risk of liver and biliary tract cancers, but convincing evidence is lacking.

PATIENTS AND METHODS

The association between dietary GI/GL and carbohydrate intake with hepatocellular carcinoma (HCC; N = 191), intrahepatic bile duct (IBD; N = 66), and biliary tract (N = 236) cancer risk was investigated in 477 206 participants of the European Prospective Investigation into Cancer and Nutrition cohort. Dietary intake was assessed by country-specific, validated dietary questionnaires. Hazard ratios and 95% confidence intervals were estimated from proportional hazard models. HBV/HCV status was measured in a nested case-control subset.

RESULTS

Higher dietary GI, GL, or increased intake of total carbohydrate was not associated with liver or biliary tract cancer risk. For HCC, divergent risk estimates were observed for total sugar = 1.43 (1.17-1.74) per 50 g/day, total starch = 0.70 (0.55-0.90) per 50 g/day, and total dietary fiber = 0.70 (0.52-0.93) per 10 g/day. The findings for dietary fiber were confirmed among HBV/HCV-free participants [0.48 (0.23-1.01)]. Similar associations were observed for IBD [dietary fiber = 0.59 (0.37-0.99) per 10 g/day], but not biliary tract cancer.

CONCLUSIONS

Findings suggest that higher consumption of dietary fiber and lower consumption of total sugars are associated with lower HCC risk. In addition, high dietary fiber intake could be associated with lower IBD cancer risk.

Healthy lifestyle index and risk of gastric adenocarcinoma in the EPIC cohort study

Several modifiable lifestyle factors, including smoking, alcohol, certain dietary factors and weight are independently associated with gastric cancer (GC); however, their combined impact on GC risk is unknown. We constructed a healthy lifestyle index to investigate the joint influence of these behaviors on GC risk within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. The analysis included 461,550 participants (662 first incident GC cases) with a mean follow-up of 11.4 years. A healthy lifestyle index was constructed, assigning 1 point for each healthy behavior related to smoking status, alcohol consumption and diet quality (represented by the Mediterranean diet) for assessing overall GC and also body mass index for cardia GC and 0 points otherwise. Risk of GC was calculated using Cox proportional hazards regression models while adjusting for relevant confounders. The highest versus lowest score in the healthy lifestyle index was associated with a significant lower risk of GC, by 51% overall (HR 0.49 95% CI 0.35, 0.70), by 77% for cardia GC (HR 0.23 95% CI 0.08, 0.68) and by 47% for noncardia GC (HR 0.53 (95% CI 0.32, 0.87), p-trends<0.001. Population attributable risk calculations showed that 18.8% of all GC and 62.4% of cardia GC cases could have been prevented if participants in this population had followed the healthy lifestyle behaviors of this index. Adopting several healthy lifestyle behaviors including not smoking, limiting alcohol consumption, eating a healthy diet and maintaining a normal weight is associated with a large decreased risk of GC.

Cancer incidence and mortality in Spain: estimates and projections for the period 1981-2012

BACKGROUND

National indicators of cancer burden are essential information for cancer surveillance and health planning, so that in countries with partial registration coverage and geographically variable risk patterns, such as Spain, this is even more relevant. This article provides estimates of cancer incidence in Spain for all cancers combined, with the single exception of non-melanoma skin cancer, and for major cancer sites over the period 1981-2006, with projections up to 2012.

PATIENTS AND METHODS

Estimates were obtained by applying the MIAMOD method, a statistical back-calculation approach, to derive incidence from mortality and relative survival data.

RESULTS

During the period 1981-2012, age-standardised incidence rates for all cancers rose from the beginning of the period and started to decline from 2000 onwards among men, and increased across the whole period among women. Differences in incidence trends between men and women might be attributable to the gender-specific case-mix of sites for all cancers, and to differences in risk factors specific to certain cancer sites in men and women, with smoking being the main factor accounting for these differences between the sexes.

CONCLUSIONS

Estimates and projections of cancer incidence and mortality show divergent trends in Spain by sex and tumour type. This information is basic for planning and enhancing public health strategies and resources.

Human natural killer cell committed thymocytes and their relation to the T cell lineage

Recent studies have demonstrated that mature natural killer (NK) cells can be grown from human triple negative (TN; CD3-, CD4-, CD8-) thymocytes, suggesting that a common NK/T cell precursor exists within the thymus that can give rise to both NK cells and T cells under appropriate conditions. In the present study, we have investigated human fetal and postnatal thymus to determine whether NK cells and their precursors exist within this tissue and whether NK cells can be distinguished from T cell progenitors. Based on the surface expression of CD56 (an NK cell-associated antigen) and CD5 (a T cell-associated antigen), three phenotypically distinctive populations of TN thymocytes were identified. CD56+, CD5-; CD56-, CD5-, and CD56-, CD5+. The CD56+, CD5- population of TN thymocytes, although displaying a low cytolytic function against NK sensitive tumor cell targets, were similar in antigenic phenotype to fetal liver NK cells, gave rise to NK cell clones, and were unable to generate T cells in mouse fetal thymic organ cultures (mFTOC). This population of thymocytes represents a relatively mature population of lineage-committed NK cells. The CD56-, CD5- population of TN thymocytes were similar to thymic NK cells in antigenic phenotype and NK cell clonogenic potential. Clones derived from this population of TN thymocytes acquired CD56 surface expression and NK cell cytolytic function. CD56-, CD5- TN thymocytes thus contain a novel population of NK cell-committed precursors. The CD56-, CD5- population of TN thymocytes also contains a small percentage of CD34+ cells, which demonstrate no in vitro clonogenic potential, but possess T cell reconstituting capabilities in mFTOC. The majority of TN thymocytes do not express CD56, but coexpress CD34 and CD5. These CD56-, CD5+, CD34+ cells demonstrate no NK or T cell clonogenic potential, but are extremely efficient in repopulating mFTOC and differentiating into CD3+, CD4+, CD8+ T cells. The results of this investigation have identified NK cells and NK cell precursors in the human thymus and have shown that these cell types are unable to differentiate along the T cell lineage pathway. Thus, while a common NK/T cell progenitor likely exists, once committed to the NK cell lineage these cells no longer have the capacity to develop along the T cell developmental pathway.

Oral and oropharyngeal cancer in Spain: influence of dietary patterns

Cancer of the oral cavity and oropharynx is a major public health problem in Spain. Tobacco and alcohol have been identified as the two major risk factors for oral cancer in most western populations. Other risk factors include diets low in fruits and vegetables, but the impact of dietary habits on the risk of these cancers has never been assessed in Spain. The objective of this study was to elucidate the role of dietary habits in oral and oropharyngeal cancer, a multicentric case-control study was conducted in three areas of Spain (Barcelona, Granada and Sevilla) between 1996 and 1999. Cases were 375 patients (71 women), with incident, histologically confirmed cancer of the oral cavity or oropharynx, and controls were 375 subjects (71 women) admitted to hospitals for conditions unrelated to smoking or alcohol drinking. Data were analysed using multivariate logistic regression procedures. After allowance for education, tobacco and alcohol use, a significant inverse association with the risk of oral and oropharyngeal cancer was found for total consumption of total green vegetables (OR 0.54, 95% CI = 0.34-0.87) and total fruit (OR 0.52, 95% CI = 0.34-0.79) with significant trends in risk. We found that the protective effect of each of these food items was consistently larger among current smokers and among heavy alcohol drinkers, following a multiplicative effect model. In conclusion, this study provides further support to the beneficial effect of high intake of vegetables and fruits on the risk of developing cancers of the oral cavity and oropharynx in Spain, particularly among current smokers and heavy alcohol drinkers.

Selective rescue of early haematopoietic progenitors in Scl–/– mice by expressing Scl under the control of a stem cell enhancer

The stem cell leukaemia gene (Scl) encodes a basic helix-loop-helix transcription factor with a pivotal role in both haematopoiesis and endothelial development. During mouse development, Scl is first expressed in extra-embryonic mesoderm, and is required for the generation of all haematopoietic lineages and normal yolk sac angiogenesis. Ectopic expression of Scl during zebrafish development specifies haemangioblast formation from early mesoderm. These results suggest that SCL is essential for establishing the transcriptional programme responsible for the formation of haematopoietic stem cells and have focused attention on the transcriptional regulation of Scl itself. Previous studies have identified a panel of Scl enhancers each of which directed expression to a subdomain of the normal Scl expression pattern. Among them, a 3′ enhancer directed expression during development to vascular endothelium and haematopoietic progenitors but not to Ter119+ erythroid cells. The expression in haematopoietic stem cells, however, remained undetermined. We demonstrate that this 3′ enhancer directs lacZ expression in transgenic mice to most foetal and adult long-term repopulating haematopoietic stem cells, and therefore functions as a stem cell enhancer. Consistent with these results, expression in Scl–/– embryos of exogenous Scl driven by the stem cell enhancer rescued the formation of early haematopoietic progenitors and also resulted in normal yolk sac angiogenesis. By contrast, erythropoiesis remained markedly deficient in rescued embryos. This observation is consistent with the inactivity of the stem cell enhancer in erythroid cells and reveals an essential role for SCL during erythroid differentiation in vivo.

Brain metabolism of ethanol and alcoholism: an update

It has long been suggested that some of the neuropharmacological, neurochemical and behavioural effects of ethanol are mediated by its first metabolite, acetaldehyde. In spite of the well documented psychoactivity of acetaldehyde, the precise role of this compound in alcohol abuse remains a matter of intense debate among scientists devoted to the study of alcoholism. Very frequently, the main drawback has been related to the presence of adequate levels of acetaldehyde or its derivatives inside the brain after ethanol ingestion. Since penetration into the central nervous system from blood of peripherically derived acetaldehyde is very low due to the high aldehyde dehydrogenase activity at the blood-brain barrier, several authors called into question the acetaldehyde implication in the toxicity and neurobehavioral effects of ethanol. The confirmation in several laboratories of the existence of enzymatic mechanisms of ethanol oxidation in the brain has revitalized the old theories supporting the acetaldehyde contribution to alcohol abuse and alcoholism. In this paper, we review current data on the brain metabolism of ethanol. We focused on the description of the enzymatic mechanisms involved in this metabolic process, reviewing the constitutive expression, catalytic activity and inhibition and inducibility of the enzymes involved in brain ethanol metabolism. We also analyze old and recent data on their regional distribution and cellular localization in the central nervous system, with special reference to the mesocorticolimbic system, a dopaminergic brain pathway that plays an important role in drug and ethanol reinforcement.

Consumption of fish and meats and risk of hepatocellular carcinoma: the European Prospective Investigation into Cancer and Nutrition (EPIC)

BACKGROUND

While higher intake of fish and lower consumption of red/processed meats have been suggested to play a protective role in the etiology of several cancers, prospective evidence for hepatocellular carcinoma (HCC) is limited, particularly in Western European populations.

METHODS

The associations of fish and meats with HCC risk were analyzed in the EPIC cohort. Between 1992 and 2010, 191 incident HCC were identified among 477 206 participants. Baseline diet was assessed using validated dietary questionnaires. A single 24-h diet recall from a cohort subsample was used for calibration. Multivariable proportional hazard regression was utilized to estimate hazard ratios (HR) and 95% confidence intervals (CI). In a nested case-control subset (HCC = 122), HBV/HCV status and liver function biomarkers were measured.

RESULTS

HCC risk was inversely associated with intake of total fish (per 20 g/day increase, HR = 0.83, 95% CI 0.74-0.95 and HR = 0.80, 95% CI 0.69-0.97 before and after calibration, respectively). This inverse association was also suggested after adjusting for HBV/HCV status and liver function score (per 20-g/day increase, RR = 0.86, 95% CI 0.66-1.11 and RR = 0.74, 95% CI 0.50-1.09, respectively) in a nested case-control subset. Intakes of total meats or subgroups of red/processed meats, and poultry were not associated with HCC risk.

CONCLUSIONS

In this large European cohort, total fish intake is associated with lower HCC risk.

Major dietary patterns and risk of coronary heart disease in middle-aged persons from a Mediterranean country: the EPIC-Spain cohort study

BACKGROUND AND AIM

No previous study has assessed the association between major dietary patterns and the risk of coronary heart disease (CHD) in a large cohort from a Mediterranean country.

METHODS AND RESULTS

We studied prospectively 40,757 persons, aged 29-69 years, participating in the Spanish cohort of the EPIC study. Food consumption was collected between 1992 and 1996 with a validated history method. Individuals were followed-up until 2004 through record linkage with hospital discharge registers, population-based registers of myocardial infarction, and mortality registers to ascertain CHD events (fatal and non-fatal acute myocardial infarction or angina requiring revascularization). Two major dietary patterns were identified from factor analysis. The first pattern was labeled as Westernized, because of the frequent consumption of refined cereals and red meat; the second was called the evolved Mediterranean pattern, because of the frequent intake of plant-based foods and olive oil. During a median follow-up of 11 years, 606 CHD events were ascertained. No association was found between the Westernized pattern and CHD risk. In contrast, the score for the evolved Mediterranean pattern was inversely associated with CHD risk (p for trend = 0.0013); when compared with the lowest quintile of the evolved Mediterranean pattern score, the multivariable hazard ratios for CHD were 0.77 (95% confidence interval 0.61-0.98) for the second quintile, 0.64 (95% CI 0.50-0.83) for the third quintile, 0.56 (95% CI 0.43-0.73) for the fourth quintile, and 0.73 (95% CI 0.57-0.94) for the fifth quintile.

CONCLUSION

A Mediterranean diet, as consumed in this study population, was associated with a lower risk of CHD.

Differentiation "in vitro" of primary and immortalized porcine mesenchymal stem cells into cardiomyocytes for cell transplantation

Cell transplantation to regenerate injured tissues is a promising new treatment for patients suffering several diseases. Bone marrow contains a population of progenitor cells known as mesenchymal stem cells (MSCs), which have the capability to colonize different tissues, replicate, and differentiate into multilineage cells. Our goal was the isolation, characterization, and immortalization of porcine MSCs (pMSCs) to study their potential differentiation "in vitro" into cardiomyocytes. pMSCs were obtained from the aspirated bone marrow of Large-White pigs. After 4 weeks in culture, adherent cells were phenotypically characterized by flow cytometry and immunochemistry by using monoclonal antibodies. Primary pMSCs were transfected with the plasmid pRNS-1 to obtain continuous growing cloned cell lines. Fresh pMSCs and immortalized cells were treated with 5-azacytidine to differentiate them into cardiomyocytes. Flow cytometry analysis of isolated pMSCs demonstrated the following phenotype, CD90(pos), CD29(pos), CD44(pos), SLA-I(pos), CD106(pos), CD46(pos) and CD45(neg), CD14(neg), CD31(neg), and CD11b(neg), similar to that described for human MSC. We derived several stable immortalized MSC cell lines. One of these, called pBMC-2, was chosen for further characterization. After "in vitro" stimulation of both primary or immortalized cells with 5-azacytidine, we obtained different percentages (30%-50%) of cells with cardiomyocyte characteristics, namely, positive for alpha-Actin and T-Troponin. Thus, primary or immortalized pMSCs derived from bone marrow and cultured were able to differentiate "ex vivo" into cardiac-like muscle cells. These elements may be potentials tools to improve cardiac function in a swine myocardial infarct model.

Nonvolatile memory with multilevel switching: a basic model

There is a current upsurge in research on nonvolatile two-terminal resistance random access memory (RRAM) for next generation electronic applications. The RRAM is composed of a simple sandwich of a semiconductor with two metal electrodes. We introduce here an initial model for RRAM with the assumption that the semiconducting part has a nonpercolating domain structure. We solve the model using numerical simulations and the basic carrier transfer mechanism is unveiled in detail. Our model captures three key features observed in experiments: multilevel switchability of the resistance, its memory retention, and hysteretic behavior in the current-voltage curve.

Diabetes and onset of natural menopause: results from the European Prospective Investigation into Cancer and Nutrition

STUDY QUESTION

Do women who have diabetes before menopause have their menopause at an earlier age compared with women without diabetes?

SUMMARY ANSWER

Although there was no overall association between diabetes and age at menopause, our study suggests that early-onset diabetes may accelerate menopause.

WHAT IS KNOWN ALREADY

Today, more women of childbearing age are being diagnosed with diabetes, but little is known about the impact of diabetes on reproductive health.

STUDY DESIGN, SIZE, DURATION

We investigated the impact of diabetes on age at natural menopause (ANM) in 258 898 women from the European Prospective Investigation into Cancer and Nutrition (EPIC), enrolled between 1992 and 2000.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Determinant and outcome information was obtained through questionnaires. Time-dependent Cox regression analyses were used to estimate the associations of diabetes and age at diabetes diagnosis with ANM, stratified by center and adjusted for age, smoking, reproductive and diabetes risk factors and with age from birth to menopause or censoring as the underlying time scale.

MAIN RESULTS AND THE ROLE OF CHANCE

Overall, no association between diabetes and ANM was found (hazard ratio (HR) = 0.94; 95% confidence interval (CI) 0.89-1.01). However, women with diabetes before the age of 20 years had an earlier menopause (10-20 years: HR = 1.43; 95% CI 1.02-2.01, <10 years: HR = 1.59; 95% CI 1.03-2.43) compared with non-diabetic women, whereas women with diabetes at age 50 years and older had a later menopause (HR = 0.81; 95% CI 0.70-0.95). None of the other age groups were associated with ANM.

LIMITATIONS, REASONS FOR CAUTION

Strengths of the study include the large sample size and the broad set of potential confounders measured. However, results may have been underestimated due to survival bias. We cannot be sure about the sequence of the events in women with a late age at diabetes, as both events then occur in a short period. We could not distinguish between type 1 and type 2 diabetes.

WIDER IMPLICATIONS OF THE FINDINGS

Based on the literature, an accelerating effect of early-onset diabetes on ANM might be plausible. A delaying effect of late-onset diabetes on ANM has not been reported before, and is not in agreement with recent studies suggesting the opposite association.

STUDY FUNDING/COMPETING INTERESTS

The coordination of EPIC is financially supported by the European Commission (DG-SANCO) and the International Agency for Research on Cancer. The national cohorts are supported by Danish Cancer Society (Denmark); Ligue Contre le Cancer, Institut Gustave Roussy, Mutuelle Générale de l'Education Nationale, Institut National de la Santé et de la Recherche Médicale (INSERM) (France); German Cancer Aid, German Cancer Research Center (DKFZ) and Federal Ministry of Education and Research (BMMF) (Germany); Ministry of Health and Social Solidarity, Stavros Niarchos Foundation and Hellenic Health Foundation (Greece); Italian Association for Research on Cancer (AIRC) and National Research Council (Italy); Dutch Ministry of Public Health, Welfare and Sports (VWS), Netherlands Cancer Registry (NKR), LK Research Funds, Dutch Prevention Funds, Dutch ZON (Zorg Onderzoek Nederland), World Cancer Research Fund (WCRF), Statistics Netherlands (The Netherlands); ERC-2009-AdG 232997 and Nordforsk, Nordic Centre of Excellence programme on Food, Nutrition and Health (Norway); Health Research Fund (FIS), Regional Governments of Andalucía, Asturias, Basque Country, Murcia (no. 6236) and Navarra, ISCIII RETIC (RD06/0020) (Spain); Swedish Cancer Society, Swedish Scientific Council and Regional Government of Skåne and Västerbotten (Sweden); Cancer Research UK, Medical Research Council, Stroke Association, British Heart Foundation, Department of Health, Food Standards Agency, and Wellcome Trust (UK). None of the authors reported a conflict of interest.