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One of several challenges in design of clinical chemoprevention trials is the selection of the dose, formulation, and dose schedule of the intervention agent. Therefore, a cross-over clinical trial was undertaken to compare the bioavailability and tolerability of sulforaphane from two of broccoli sprout–derived beverages: one glucoraphanin-rich (GRR) and the other sulforaphane-rich (SFR). Sulforaphane was generated from glucoraphanin contained in GRR by gut microflora or formed by treatment of GRR with myrosinase from daikon (Raphanus sativus) sprouts to provide SFR. Fifty healthy, eligible participants were requested to refrain from crucifer consumption and randomized into two treatment arms. The study design was as follows: 5-day run-in period, 7-day administration of beverages, 5-day washout period, and 7-day administration of the opposite intervention. Isotope dilution mass spectrometry was used to measure levels of glucoraphanin, sulforaphane, and sulforaphane thiol conjugates in urine samples collected daily throughout the study. Bioavailability, as measured by urinary excretion of sulforaphane and its metabolites (in approximately 12-hour collections after dosing), was substantially greater with the SFR (mean = 70%) than with GRR (mean = 5%) beverages. Interindividual variability in excretion was considerably lower with SFR than with GRR beverage. Elimination rates were considerably slower with GRR, allowing for achievement of steady-state dosing as opposed to bolus dosing with SFR. Optimal dosing formulations in future studies should consider blends of sulforaphane and glucoraphanin as SFR and GRR mixtures to achieve peak concentrations for activation of some targets and prolonged inhibition of others implicated in the protective actions of sulforaphane. Cancer Prev Res; 4(3); 384–95. ©2011 AACR.

Related Article from Is It Time to Advance the Chemoprevention of Environmental Carcinogenesis with Microdosing Trials?

Supplementary Tables from Bioavailability of Sulforaphane from Two Broccoli Sprout Beverages: Results of a Short-term, Cross-over Clinical Trial in Qidong, China

Supplementary Figure from Bioavailability of Sulforaphane from Two Broccoli Sprout Beverages: Results of a Short-term, Cross-over Clinical Trial in Qidong, China

Enteropathy is a pathophysiological condition characterized by decreased intestinal barrier function and absorption. Past studies have hypothesized that mycotoxins might impair children's growth by causing intestinal enteropathy, including interactions between mycotoxins and pathogens. We investigated the association of two mycotoxins, aflatoxin B

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) has emerged as a major liver disease worldwide. Bile acid dysregulation has been suggested to be a key feature in its pathogenesis and progression. AIMS: To characterize the relationship between bile acid levels and NAFLD on the population level. METHODS: A cross-sectional study in Guatemala was conducted in 2016 to examine the prevalence of NAFLD. Participants (n=415) completed questionnaires, donated blood samples and had a brief medical exam. NAFLD was determined by calculation of the Fatty Liver Index. The levels of 15 circulating bile acids were determined by LC-MS/MS. Adjusted prevalence odds ratios (POR(adj)) and 95%CI were calculated to examine the relationships between bile acid levels (in tertiles) and NAFLD. RESULTS: Persons with NAFLD had significantly higher levels of the conjugated primary bile acids glycocholic acid (GCA) (POR(adj T3 vs T1)=1.85), taurocholic acid (TCA) (POR(adj T3 vs T1)=2.45) and taurochenodeoxycholic acid (TCDCA) (POR(adj T3 vs T1)=2.10), as well as significantly higher levels the unconjugated secondary bile acid, deoxycholic acid (DCA) (POR(adj T3 vs T1)=1.78) and its conjugated form, taurodeoxycholic acid (TDCA) (POR(adj T3 vs T1)=1.81). CONCLUSIONS: The bile acid levels of persons with, and without, NAFLD differed significantly. Among persons with NAFLD, higher levels of the conjugated forms of CA (i.e., GCA, TCA) and the secondary bile acids that derive from CA (i.e., DCA, TDCA) may indicate there is hepatic overproduction of CA, which may affect the liver via aberrant signaling mediated by the bile acids.

Background: In utero or early-life exposure to aflatoxin, which contaminates staple crops in disadvantaged settings, may compromise pregnancy and infant outcomes, but investigations into the extent, persistence, and determinants of aflatoxin exposure at these life stages have lacked longitudinal data collection and broad geographic representation. Objectives: Aflatoxin exposure and selected determinants thereof were characterized in mother–child dyads with serial plasma/serum samples in prenatal, perinatal, and early life in Malawi and Bangladesh. Methods: Circulating aflatoxin B1 (AFB1)–lysine albumin adducts were measured in dyads from Bangladesh (n = 573; maternal first and third trimester, 3 mo postpartum, cord blood, infant 24 mo) and Malawi (n = 255; maternal second and third trimester, 6 mo postpartum, infant 6 and 18 mo) with isotope dilution mass spectrometry. We examined AFB1-lysine adduct magnitude, persistence, seasonality, and associations with infant feeding, and estimated daily AFB1 intake. Results: Maternal AFB1-lysine was higher in Malawi (98% detectable; median: 0.469, IQR: 0.225–1.027 pg/μL) than in Bangladesh (59%; 0.030, nondetectable [nd]–0.077 pg/μL). Although estimated dietary exposure in Malawi was temporally stable (648 ng AFB1/day), estimated intake in Bangladesh was reduced by 94% between rainy and winter seasons (98 to 6 ng/day). AFB1-lysine was low in cord blood from Bangladesh (15% detectable; 0.045, 0.031–0.088 pg/μL among detectable) and in Malawian infants at 6 mo of age (0.072, nd–0.236 pg/μL), but reached maternal concentrations by 18 or 24 mo (Bangladesh: 0.034, nd–0.063 pg/μL; Malawi: 0.370, 0.195–0.964 pg/μL). In Malawian infants, exclusive breastfeeding at 3 mo was associated with 58% lower AFB1-lysine concentrations at 6 mo compared with other feeding modes (P = 0.010). Conclusions: Among pregnant women, aflatoxin exposure was persistently high in Malawi, while lower and seasonal in Bangladesh. Infants were partially protected from exposure in utero and with exclusive breastfeeding, but exposures reached adult levels by 18–24 mo of age. The Bangladesh and Malawi trials are registered at clinicaltrials.gov as NCT00860470 and NCT01239693. Curr Dev Nutr 2022;6:nzab153. publishedVersion

During the 60 years since the first scientific reports about a relation between aflatoxin exposure and adverse health consequences, both in animals and humans, there has been a remarkable number of basic, clinical and population science studies characterising the impact of this mycotoxin on diseases such as liver cancer. Many of these human investigations to date have focused on populations residing in Asia and Africa due to the high incidence of liver cancer and high exposures to aflatoxin. These studies formed the basis for the International Agency for Research on Cancer to classify the aflatoxins as Group 1 known human carcinogens. In addition, aflatoxin contamination levels have been used in international commodity trade to set the price of various staples such as maize and groundnuts. While there have been many case-control and prospective cohort studies of liver cancer risk over the years there have been remarkably few investigations focused on liver cancer in Latin America. Our interdisciplinary and multiple institutional collaborative has been developing a long-term strategy to characterise the role of aflatoxin and other mycotoxins as health risk factors in Guatemala and neighbouring countries. This paper summarises a number of the investigations to date and provides a roadmap of our strategies for the near term to discern the emergent aetiology of liver cancer in this region. With these data in hand public health-based prevention strategies could be strategically implemented and conducted to lower the impact of these mycotoxins on human health.

Significance Recently, investigators have shown that only a few driver gene mutational events appear to be needed for cancer to occur. However, the reason that some mutational events precede others in the same cancer and the explanation for tissue-specific differences in this timing, remain mysterious. We here combine mathematical modeling with epidemiologic studies and sequencing data to address these questions. We suggest that the first driver event in cancers generally occurred at early ages and provide estimates for the fitness of different types of drivers during tumor evolution, showing how they vary with the tissue of origin., Cancer is driven by the sequential accumulation of genetic and epigenetic changes in oncogenes and tumor suppressor genes. The timing of these events is not well understood. Moreover, it is currently unknown why the same driver gene change appears as an early event in some cancer types and as a later event, or not at all, in others. These questions have become even more topical with the recent progress brought by genome-wide sequencing studies of cancer. Focusing on mutational events, we provide a mathematical model of the full process of tumor evolution that includes different types of fitness advantages for driver genes and carrying-capacity considerations. The model is able to recapitulate a substantial proportion of the observed cancer incidence in several cancer types (colorectal, pancreatic, and leukemia) and inherited conditions (Lynch and familial adenomatous polyposis), by changing only 2 tissue-specific parameters: the number of stem cells in a tissue and its cell division frequency. The model sheds light on the evolutionary dynamics of cancer by suggesting a generalized early onset of tumorigenesis followed by slow mutational waves, in contrast to previous conclusions. Formulas and estimates are provided for the fitness increases induced by driver mutations, often much larger than previously described, and highly tissue dependent. Our results suggest a mechanistic explanation for why the selective fitness advantage introduced by specific driver genes is tissue dependent.

In utero or early-life exposure to aflatoxin, which contaminates staple crops in disadvantaged settings, may compromise pregnancy and infant outcomes, but investigations into the extent, persistence, and determinants of aflatoxin exposure at these life stages have lacked longitudinal data collection and broad geographic representation.Aflatoxin exposure and selected determinants thereof were characterized in mother-child dyads with serial plasma/serum samples in prenatal, perinatal, and early life in Malawi and Bangladesh.Circulating aflatoxin BMaternal AFBAmong pregnant women, aflatoxin exposure was persistently high in Malawi, while lower and seasonal in Bangladesh. Infants were partially protected from exposure in utero and with exclusive breastfeeding, but exposures reached adult levels by 18-24 mo of age. The Bangladesh and Malawi trials are registered at clinicaltrials.gov as NCT00860470 and NCT01239693.

Objective Persistent organic pollutants (POPs) are lipophilic environmental toxicants that accumulate in adipose tissue. Weight loss leads to mobilization and increased redistribution of these toxicants. Many are obesogens and endocrine disruptors. Increased exposure could pose long-term health risks. The study objective was to measure the changes in serum concentrations of lipophilic POPs during significant weight loss. Methods This study enrolled 27 patients at a university hospital in a longitudinal, 6-month, observational study examining changes in POP blood levels after bariatric surgery. The primary outcome was the changes in the concentrations of 24 polychlorinated biphenyls (PCBs), 9 organochlorine pesticides (OCPs), 11 polybrominated diphenyl ethers, 2,2',4,4',5,5'-hexabromobiphenyl, and 4 perfluorochemicals (PFCs). Results Older adults (those born before 1976) had baseline levels of PCBs, OCPs, and PFCs that were two- to fivefold higher than younger adults (those born after 1976). Older adults had greater increases in PCBs, OCPs, and polybrominated diphenyl ethers associated with weight loss. Conversely, younger adults had greater increases in PFCs associated with weight loss. On average, blood POP levels increased as weight loss occurred. Conclusions Although weight loss is considered beneficial, the release and redistribution of POPs to other lipid-rich organs such as the brain, kidneys, and liver warrant further investigation. Interventions should be considered to limit organ exposure to POPs when weight loss interventions are planned.

Exploration of animal models leads to discoveries that can reveal candidate biomarkers for translation to human populations. Herein, a model of hepatocarcinogenesis and protection was used in which rats treated with aflatoxin (AFB1 ) daily for 28 days (200 µg/kg BW) developed tumors compared with rats completely protected from tumors by concurrent administration of the chemoprotective agent, 1-[2-cyano-3-,12-dioxooleana-1,9(11)-dien-28-oyl]imidazole (CDDO-Im). Differential expression of miRNAs in tumors (AFB1 ) and nontumor (AFB1 + CDDO-Im) bearing livers and their levels in sera over the life-course of the animals was determined. miRNA transcriptome analysis identified 17 miRNAs significantly upregulated at greater than five-fold in the tumors. The ten most dysregulated miRNAs judged by fold-change and biological significance were selected for further study, including liver-specific miR-122-5p. Validation of sequencing results by real-time PCR confirmed the upregulation of the majority of these miRNAs in tumors, including miR-182, as well as miR-224-5p as the most dysregulated of these miRNAs (over 400-fold). The longitudinal analysis of levels of miR-182 in sera demonstrated significant and persistent increases (5.13-fold; 95% CI: 4.59-5.70). The increase in miR-182 was detected months before any clinical symptoms were present in the animals. By the terminal time point of the study, in addition to elevated levels of serum miR-182, serum miR-122-5p was also found to be increased (>1.5-fold) in animals that developed hepatocarcinomas. Thus, using the data from an unbiased discovery approach of the tissue findings, serum miR-182 was found to track across the complex, multistage process of hepatocarcinogenesis opening an opportunity for translation to human populations.

Background: To evaluate the association of liver fibrosis scores with PSA level among U.S. adult men overall and by race/ethnicity. Methods: Data from the National Health and Nutrition Examination Survey (NHANES), 2001–2010, were used. Males ages ≥40 years without a prostate cancer diagnosis and who had serum PSA, liver enzymes, albumin, and platelet counts measured as part of NHANES protocol were included. Liver fibrosis was measured using three scores: aspartate aminotransferase to platelet ratio index (APRI), fibrosis 4 index (FIB-4), and NAFLD fibrosis score (NFS). We assessed overall and race/ethnicity-stratified geometric mean PSA by fibrosis score using predictive margins by linear regression, and the association of abnormal fibrosis scores (APRI > 1, FIB-4 > 2.67, NFS > 0.676) and elevated PSA (>4 ng/mL) by logistic regression. Results: A total of 6,705 men were included. Abnormal liver fibrosis scores were present in 2.1% (APRI), 3.6% (FIB-4), and 5.6% (NFS). Men with higher fibrosis scores had lower geometric mean PSA (all Ptrend < 0.02). Men with abnormal APRI had a lower odds of PSA > 4 ng/mL [adjusted OR (aOR) = 0.33; 95% confidence interval (CI), 0.11–0.96]. Compared with men with 0 abnormal scores, those with 2 or 3 abnormal fibrosis scores had a lower odds of PSA > 4 ng/mL (aOR = 0.55; 95% CI, 0.33–0.91). The patterns were similar by race/ethnicity. Conclusions: Men of all race/ethnicities with higher liver fibrosis scores had lower serum PSA, and men with advanced fibrosis scores had a lower odds of an elevated PSA. Impact: These findings support further research to inform the likelihood of delay in prostate cancer detection in men with abnormal liver function.

Within the last decade, for the first time in human history, deaths from chronic diseases have exceeded mortality from acute causes worldwide. These chronic diseases encompass a spectrum of cancers, cardiovascular diseases, neurological diseases, and the emerging consequences of obesity and over nutrition. Further, there are more people today who are cancer survivors as well as people who are afflicted with multiple chronic diseases. This results in an emerging new group of susceptible populations with complex biology’s that will drive the development of new experimental models. Since environmental exposures have a profound impact from the etiology of disease through progression and response to therapeutic and preventive interventions, a new appreciation of the role of environmental health has emerged. This mini-review will attempt to provide a global perspective on the transitions that have occurred in environmental health over the last 200 years and how these transitions are impacting diverse populations globally. The extraordinary advances in our understanding of the biology of normal development and the molecular progression of disease processes have created unprecedented opportunities for the translation of basic science to therapy and prevention. The need to integrate findings from the biological, physical, engineering, social, and behavioral sciences, sometimes called convergence, points to an imperative to develop new team science approaches to address the health consequences of environmental exposures. Finally, as it is increasingly recognized that disease outbreaks in one part of the world are no longer isolated from global impacts, there is a need to assure that our next generations of trained scientists have grounding in global collaborations. Impact statement There is a rapidly occurring, dynamic change, in the causes of morbidity and mortality in different populations across the globe. More people today are being diagnosed and treated for chronic diseases such as cancer, cardiovascular disease, and diabetes than ever before. Environmental exposures across the lifespan have a profound impact on the outcomes of these chronic diseases. Further, there are more people living today who have survived their therapy from these diagnoses and who are now differentially susceptible to environmental exposures. Collectively, this poses both the challenge and opportunity to the experimental biology and medicine community to build new models that reflect this changing human situation. The extraordinary advances in our understanding of the biology of disease provide extraordinary insights for both therapeutic and prevention strategies. Multidisciplinary teams including biological, physical, engineering and social and behavioral scientists will be needed to address this problem over the next several decades.

Background There are no data on the prevalence of non-alcoholic fatty liver disease (NAFLD) in general population samples in Guatemala or in other Central American countries. The prevalence and distribution of NAFLD and its associated risk factors were evaluated in a population-based sample of adults in Guatemala. Methods Cross-sectional study of 411 men and women 40 years of age or older residing in urban and rural areas of Guatemala. Metabolic outcomes included obesity, central obesity, hypercholesterolemia, diabetes, and metabolic syndrome (MetS). Liver disease outcomes included elevated liver enzymes, elevated Fatty Liver Index (FLI), and elevated FIB-4 score. Results The overall prevalence of obesity, central obesity, diabetes, and MetS were 30.9, 74.3, 21.6, and 64.2%, respectively. The fully-adjusted prevalence ratios (95% CI) for obesity, central obesity, diabetes, and MetS comparing women to men were 2.83 (1.86–4.30), 1.72 (1.46–2.02), 1.18 (1.03–1.34), and 1.87 (1.53–2.29), respectively. The overall prevalence of elevated liver enzymes (ALT or AST), elevated FLI, and elevated FIB-4 scores were 38.4, 60.1, and 4.1%, respectively. The fully-adjusted prevalence ratios (95% CI) for elevated liver enzymes (either ALT or AST) and elevated FLI score comparing women to men were 2.99 (1.84–4.86) and 1.47 (1.18–1.84), respectively. Conclusions The prevalence of metabolic abnormalities and liver outcomes in this general population study was very high. The prevalence of metabolic and liver abnormalities was particularly high among women, an observation that could explain the atypical 1:1 male to female ratio of liver cancer in Guatemala.

Dietary exposure to aflatoxin B(1) (AFB(1)) is a significant contributor to the incidence of hepatocellular carcinomas globally. AFB(1) exposure leads to the formation of AFB(1)-N(7)-guanine (AFB(1)-N(7)-Gua) and two diastereomers of the imidazole ring-opened 8,9-dihydro-8-(2,6-diamino-4-oxo-3,4-dihydropyrimid-5-yl-formamido)-9-hydroxyaflatoxin B(1) (AFB(1)-FapyGua) in DNA. These adducts lead to G → T transversion mutations with the ring-opened adduct being more mutagenic than the cationic species. Accurate measurement of these three adducts as biomarkers in DNA and urine will help identify dietary exposure to AFB(1) as a risk factor in the development of hepatocellular carcinoma worldwide. Herein, we report an improved methodology for the measurement of AFB(1)-N(7)-Gua and the two diastereomers of AFB(1)-FapyGua using liquid chromatography-tandem mass spectrometry with isotope dilution. We measured the levels of these compounds in liver DNA of six control mice and six AFB(1)-treated mice. Levels varying from 1.5 to 45 lesions/10(6) DNA bases in AFB(1)-treated mice were detected depending on the compound and animal. No background levels of these adducts were detected in control mice. We also tested whether the AFB(1) treatment caused oxidatively induced DNA base damage using gas chromatography-tandem mass spectrometry with isotope dilution. Although background levels of several pyrimidine- and purine-derived lesions were detected, no increases in these levels were found upon AFB(1) treatment of mice. On the other hand, significantly increased levels of (5′R)- and (5′S)-8,5′-cyclo-2′-deoxyadenosines were observed in liver DNA of AFB(1)-treated mice. The impact of this work is expected to achieve the accurate measurement of three AFB(1)-DNA adducts and oxidatively induced DNA lesions as biomarkers of AFB(1) exposure as germane to investigations designed for the prevention of aflatoxin-related hepatocellular carcinomas and for determining the effects of genetic deficiencies in human populations.

The aim of this study was to determine if plasma cyclohexanone and metabolites are associated with clinical outcomes of children on extracorporeal membrane oxygenation (ECMO) support. We performed a secondary analysis of a prospective observational study of children on ECMO support at two academic centers between July 2010 and June 2015. We measured plasma cyclohexanone and metabolites on the first and last days of ECMO support. Unfavorable outcome was defined as in-hospital death or discharge Pediatric Cerebral Performance Category score > 2 or decline ≥ 1 from baseline. Among 90 children included, 49 (54%) had unfavorable outcome at discharge. Cyclohexanediol, a cyclohexanone metabolite, was detected in all samples and at both time points; concentrations on the first ECMO day were significantly higher in those with unfavorable versus favorable outcome at hospital discharge (median, 5.7 ng/µl; interquartile range [IQR], 3.3-10.6 ng/µl vs. median, 4.2 ng/µl; IQR, 1.7-7.3 ng/µl; p = 0.04). Twofold higher cyclohexanediol concentrations on the first ECMO day were associated with increased risk of unfavorable outcome at hospital discharge (multivariable-adjusted hazard ratio [HR], 1.24 [95% CI, 1.05-1.48]). Higher cyclohexanediol concentrations on the first ECMO day were not significantly associated with new abnormal neuroimaging or 1-year Vineland Adaptive Behavior Scales-II score < 85 or death among survivors.

Outdoor air pollution, a spatially and temporally complex mixture, is a human carcinogen. However, ambient measurements may not reflect subject-level exposures, personal monitors do not assess internal dose, and spot assessments of urinary biomarkers may not recapitulate chronic exposures. Nucleophilic sites in serum albumin – particularly the free thiol at Cys(34) – form adducts with electrophiles. Due to the 4-week lifetime of albumin in circulation, accumulating adducts can serve as intermediate- to long-residence biomarkers of chronic exposure and implicate potential biological effects. Employing nanoflow liquid chromatography-high resolution mass spectrometry (nLC-HRMS) and parallel reaction monitoring (PRM), we have developed and validated a novel targeted albumin adductomics platform capable of simultaneously monitoring dozens of Cys(34) adducts per sample in only 2.5 μL of serum, with on-column limits of detection in the low femtomolar range. Using this platform, we characterized the magnitude and impact of ambient outdoor air pollution exposures with three repeated measurements over 84 days in n=26 non-smoking women (n=78 total samples) from Qidong, China, an area with a rising burden of lung cancer incidence. In concordance with seasonally rising ambient concentrations of NO(2), SO(2), and PM(10) measured at stationary monitors, we observed elevations in concentrations of Cys(34) adducts of benzoquinone (p

Background and aims: Liver cancer is one of the most dominant malignant tumors in the world. The trends of liver cancer mortality over the past six decades have been tracked in the epidemic region of Qidong, China. Using epidemiological tools, we explore the dynamic changes in age-standardized rates to characterize important aspects of liver cancer etiology and prevention. Methods Mortality data of liver cancer in Qidong from 1958 to 1971 (death retrospective survey) and from 1972 to 2017 (cancer registration) were tabulated for the crude rate (CR), and age-standardized rate and age-birth cohorts. The average annual percentage change was calculated by the Joinpoint Regression Program. Results The natural death rate during 1958–2017 decreased from 9‰ to 5.4‰ and then increased to 8‰ as the population aged; cancer mortality rates rose continuously from 57/105 to 240/105. Liver cancer mortality increased from 20/105 to 80/105, and then dropped to less than 52/105 in 2017. Liver cancer deaths in 1972–2017 accounted for 30.53% of all cancers, with a CR of 60.48/105, age-standardized rate China (ASRC) of 34.78/105, and ASRW (world) of 45.71/105. Other key features were the CR for males and females of 91.86/105 and 29.92/105, respectively, with a sex ratio of 3.07:1. Period analysis showed that the ASRs for mortality of the age groups under 54 years old had a significant decreasing trend. Importantly, birth cohort analysis showed that the mortality rate of liver cancer in 40–44, 35–39, 30–34, 25–29, 20–24, 15–19 years cohort decreased considerably, but the rates in 70–74, and 75+ increased. Conclusions The crude mortality rate of liver cancer in Qidong has experienced trends from lower to higher levels, and from continued increase at a high plateau to most recently a gradual decline, and a change greatest in younger people. Many years of comprehensive prevention and intervention measures have influenced the decline of the liver cancer epidemic in this area. The reduction of intake levels of aflatoxin might be one of the most significant factors as evidenced by the dramatic decline of exposure biomarkers in this population during the past three decades.

BACKGROUND & AIMS This study aimed to analyse the association of sex hormone levels with liver enzyme levels and non-alcoholic fatty liver disease (NAFLD) in a nationally representative sample of men. METHODS 919 men from the US National Health and Nutrition Examination Study (NHANES) III were included in this cross-sectional analysis of data from 1988-1991. We used existing data on serum total and free testosterone, total and free estradiol, androstanediol glucuronide (AAG), sex steroid binding globulin (SHBG), and estimated their associations with aspartate aminotransferase (AST), and alanine aminotransferase (ALT) and NAFLD, as determined using ultrasound, after adjusting for possible confounders including age, race, smoking, alcohol, physical activity, waist circumference and steroid hormones. RESULTS Lower total testosterone and higher free estradiol were associated with higher odds of NAFLD after adjusting for confounders including the other sex hormones. Lower total testosterone was associated with higher odds of elevated AST, but not ALT. Free testosterone, total estradiol, SHBG and AAG were not associated with NAFLD or liver enzymes. CONCLUSIONS This study supports an inverse association between total testosterone concentration and NAFLD in men independent of other sex hormones (SHBG, AAG, estradiol) and known risk factors such as obesity, age and lifestyle. Exploration of whether total testosterone might be a non-invasive marker for NAFLD diagnosis is warranted.

Collectively, liver cancer accounts for 8.2% of all reported cancer deaths in men and women, and it is the third/fourth most common cause of cancer mortality worldwide. Currently, there are more than 840,000 new cases of this nearly always fatal cancer each year. The combined age-standardized rate of mortality from liver cancer for men and women worldwide was 8.5 per 100,000 in 2018. The countries that traditionally are considered as part of the Middle East span two World Health Organization (WHO) regions: Eastern Mediterranean and Europe. Of these countries, Egypt has the second highest age-standardized rate of mortality from liver cancer, 49.0 and 16.7 per 100,000 for men and women, respectively, in the world. Indeed, this mortality rate is only exceeded globally by Mongolia. Further, liver cancer has a poor prognosis, less than a 15% 5-year survival. The etiologies of liver cancer diagnosed today are well understood, and with the emergence of fatty liver disease as a risk factor, this cancer is especially emergent in the countries of the Middle East where a majority of adults are now obese and the rates are rising.

ObjectiveIn Guatemala, cirrhosis is among the 10 leading causes of death, and mortality rates have increased lately. The reasons for this heavy burden of disease are not clear as the prevalence of prominent risk factors, such as hepatitis B virus, hepatitis C virus and heavy alcohol consumption, appears to be low. Aflatoxin B1 (AFB1) exposure, however, appears to be high, and thus could be associated with the high burden of cirrhosis. Whether AFB1 increases the risk of cirrhosis in the absence of viral infection, however, is not clear.DesignCirrhosis cases (n=100) from two major referral hospitals in Guatemala City were compared with controls (n=200) from a cross-sectional study. Logistic regression was used to estimate the ORs and 95% CIs of cirrhosis and quintiles of AFB1 in crude and adjusted models. A sex-stratified analysis was also conducted.ResultsThe median AFB1 level was significantly higher among the cases (11.4 pg/mg) than controls (5.11 pg/mg). In logistic regression analyses, higher levels of AFB1 was associated with cirrhosis (quintile 5 vs quintile 1, OR: 11.55; 95% CI 4.05 to 32.89). No attenuation was observed with adjustment by sex, ethnicity, hepatitis B virus status, and heavy alcohol consumption. A significantly increasing trend in association was observed in both models (p trend 1 association was more prominent among men.ConclusionsThe current study found a significant positive association between AFB1 exposure and cirrhosis. Mitigation of AFB1 exposure and a better understanding of additional risk factors may be important to reduce the burden of cirrhosis in Guatemala.

Background Previous studies have suggested an association between Helicobacter pylori (H pylori) and nonalcoholic fatty liver disease (NAFLD). The aim of the current study was to examine the association in Guatemala, a region with elevated prevalences of both H pylori and NAFLD. Associations between H pylori and other metabolic conditions were also examined, as were associations between H hepaticus and H bilis and the metabolic conditions. Materials & methods The analysis included 424 participants from a cross-sectional study in Guatemala. H pylori seropositivity was defined as positivity for ≥ 4 antigens. Seropositivities for H bilis and H hepaticus were defined as positivity for ≥ 2 antigens. NAFLD was estimated using the Fatty Liver Index and the Hepatic Steatosis Index. Other conditions examined were obesity, central obesity, hypercholesterolemia, low HDL, diabetes and metabolic syndrome (MetSyn). Prevalence odds ratios (POR) and 95% confidence intervals (CIs) were estimated. Results No overall associations between H pylori, H hepaticus, or H bilis and NAFLD or related metabolic conditions were found. Seropositivity for H pylori antigens CagA and VacA and H hepaticus antigen HH0713 was each significantly associated with NAFLD, however. In addition, associations were observed between the H pylori antigens HyuA, HP1564, and UreA and specified metabolic conditions. Conclusions While no overall associations between H pylori or Helicobacter species with NAFLD or related conditions were observed, some selected Helicobacter spp. antigens were associated with NAFLD. Further research is warranted to examine whether H. species are associated with any metabolic condition.

Background and aims Guatemala has the highest incidence of hepatocellular carcinoma (HCC) in the Western hemisphere. The major risk factors in Guatemala are not well characterized, but the prevalence of hepatitis B virus (HBV) and hepatitis C virus (HCV) appears to be low, while the prevalence of aflatoxin (AFB1) exposure appears to be high. To examine whether AFB1 may contribute to the elevated incidence of HCC in Guatemala, this study examined the frequency of the AFB1‐signature mutation in the TP53 gene (R249S) as well as other somatic mutations. In addition, we assessed whether the frequency of the TP53 mutation differed by sex. Methods Formalin‐fixed, paraffin‐embedded (FFPE) HCC tissues were obtained from three hospitals in Guatemala City between 2016 and 2017. In addition, tumor tissues preserved in RNAlater were also obtained. Sociodemographic and clinical information including HBV and HCV status were collected. Targeted sequencing of TP53 was performed in the FFPE samples, and a panel of 253 cancer‐related genes was sequenced in the RNAlater samples. Results Ninety‐one FFPE tissues were examined, from 52 men and 39 women. Median (IQR) age at diagnosis was 62 (51‐70). Among those with known HBV and HCV status, two were HBV+ and three were HCV+. Overall, 47% of the HCCs had a TP53 mutation. The AFB1‐signature R249S mutation was present in 24%. No overlap between the R249S mutation and HBV+ was observed in this cohort. Among 18 RNAlater samples examined, 44% had any TP53 mutation and 33% had the R249S mutation. Other somatic mutations were identified in known HCC driver genes. Conclusions The presence of the TP53 R249S mutation in the samples studied suggests that AFB1 may contribute to the high incidence of HCC in Guatemala. The proportion of HBV+ tumors was low, suggesting that AFB1 may be associated with HCC in the absence of concomitant HBV infection. Further investigation of AFB1 and other risk factors for HCC in Guatemala is warranted.

Background and aims Guatemala has the highest incidence of hepatocellular carcinoma (HCC) in the Western hemisphere. The major risk factors in Guatemala are not well characterized, but the prevalence of hepatitis B virus (HBV) and hepatitis C virus (HCV) appears to be low, while the prevalence of aflatoxin (AFB1) exposure appears to be high. To examine whether AFB1 may contribute to the elevated incidence of HCC in Guatemala, this study examined the frequency of the AFB1‐signature mutation in the TP53 gene (R249S) as well as other somatic mutations. In addition, we assessed whether the frequency of the TP53 mutation differed by sex. Methods Formalin‐fixed, paraffin‐embedded (FFPE) HCC tissues were obtained from three hospitals in Guatemala City between 2016 and 2017. In addition, tumor tissues preserved in RNAlater were also obtained. Sociodemographic and clinical information including HBV and HCV status were collected. Targeted sequencing of TP53 was performed in the FFPE samples, and a panel of 253 cancer‐related genes was sequenced in the RNAlater samples. Results Ninety‐one FFPE tissues were examined, from 52 men and 39 women. Median (IQR) age at diagnosis was 62 (51‐70). Among those with known HBV and HCV status, two were HBV+ and three were HCV+. Overall, 47% of the HCCs had a TP53 mutation. The AFB1‐signature R249S mutation was present in 24%. No overlap between the R249S mutation and HBV+ was observed in this cohort. Among 18 RNAlater samples examined, 44% had any TP53 mutation and 33% had the R249S mutation. Other somatic mutations were identified in known HCC driver genes. Conclusions The presence of the TP53 R249S mutation in the samples studied suggests that AFB1 may contribute to the high incidence of HCC in Guatemala. The proportion of HBV+ tumors was low, suggesting that AFB1 may be associated with HCC in the absence of concomitant HBV infection. Further investigation of AFB1 and other risk factors for HCC in Guatemala is warranted.

Background: There was rare data to describe decades’ long natural history or changes of a cancer. We describe and explore the characteristics and trend of liver cancer mortality in Qidong, China over the past 60 years. Methods: Mortality data of liver cancer in Qidong from 1958 to 1971 (death retrospective survey) and from 1972 to 2017 (cancer registration) were tabulated for the crude rate (CR), age-standardized rate (by China’s population, ASRC and by Worlld population, ASRW) and age-birth cohorts. The average annual percentage change (AAPC) was calculated by the Joinpoint Regression Program. Findings: The natural death rate during 1958-2017 decreased from 9‰ to 5.4‰ and then increased to 8‰; Cancer mortality rate rose continuously from 57/10 5 to 240/10 5 . Liver cancer mortality increased from 20/10 5 to 80/105, and then dropped to less than 52/105 in 2017. Liver cancer deaths in 1972-2017 accounted for 30.53% of all cancers, with CR of 60.48/105, ASRC of 34.78/105, and ASRW of 45.71/105. The truncated rate of 35-64 was 104.06/105, cumulative mortality rate of 0-74 years, and cumulative risk rate were 4.79% and 4.68%, respectively. The CR for males and females were 91.86/105 and 29.92/105, respectively, with a sex ratio of 3.07:1. From 1972 to 2017, the AAPC of the ASRW derived by the Joinpoint analysis was -1.3%, in which -1.5% for men and -1.0% for women. The AAPC of joinpoints was -1.8% for both sexes, and -1.8% for males, -1.4% for females, respectively. Period analysis shows that the age-specific mortality rates of the age groups under 54 years old had a significant decreasing trend. Birth cohort analysis showed that the mortality rate of liver cancer in 40-44, 35-39, 30-34, 25-29, 20-24, 15-19 years cohort decreased, but the rates in 70-74, and 75+ were increased. Interpretation: The crude mortality rate of liver cancer in Qidong has experienced trends from lower to higher levels, and from continued increase at a high plateau to most recently a gradual decline, and change greatest in younger people. Many years of comprehensive prevention and intervention measures may have influenced the decrease of the liver cancer epidemic in this area. The reduction of intake levels of aflatoxin might be one of the most significant factors as evidenced by the decline of exposure biomarkers in this population. Funding Statement: The US National Institutes of Health through grants R01 CA196610 and R35 CA197222, the Chinese National Key Projects (2008ZX10002-015, 2008ZX10002-017, 2012ZX10002009), the Scientifc Research Projet of “333 Project” in Jiangsu (BRA2019030), and the Nantong Science and Techonology Project (MS22019008). Declaration of Interests: The authors declare no competing interests related to this study.

Objective:Chronic aflatoxin exposure has been associated with childhood stunting (length-for-age/height-for-age < –2 sd), while data lacks for Bangladesh, a country with substantial burden of childhood stunting. This paper examined the association between aflatoxin exposure and childhood stunting in a slum setting of Dhaka city.Design:In this MAL-ED aflatoxin birth cohort study, plasma samples were assayed for aflatoxin B1-lysine adduct (AFB1-lys) by MS at 7, 15, 24 and 36 months of age for 208, 196, 173 and 167 children to assess chronic aflatoxin exposure. Relationship between aflatoxin exposure and anthropometric measures was examined by mixed-effects logistic regression models.Setting and participants:The study was conducted in Mirpur, Dhaka, where children were followed from birth to 36 months.Results:Prevalence of stunting increased from 21 % at 7 months to 49 % at 36 months of age. Mean AFB1-lys concentrations at 7, 15, 24 and 36 months were 1·30 (range 0·09–5·79), 1·52 (range 0·06–6·35), 3·43 (range 0·15–65·60) and 3·70 (range 0·09–126·54) pg/mg albumin, respectively, and the percentage of children with detectable AFB1-lys was 10, 21, 18 and 62 %, respectively. No association was observed between aflatoxin exposure and stunting in multivariable analyses. Factors associated with childhood stunting were age, low birth weight, maternal height, stool myeloperoxidase and number of people sleeping in one room.Conclusions:A relatively lower exposure to aflatoxin may not influence the linear growth of children. This finding indicates a threshold level of exposure for linear growth deficit and further investigation in other areas where higher concentrations of aflatoxin exposure exist.

Background Exposure to particulate matter (PM) is increasing worldwide as a result of increased human activity, the rapid industrialization of developing countries, and effects of climate change. Adverse effects of PM on human health are well documented, and because PM exposure occurs mostly through the airways, PM has especially deleterious impact on the lungs. Objective We investigated whether surrogate PM particles like carbon black (CB), diesel exhaust particle (DEP), coal fly ash (CFA) can recapitulate the allergic airway inflammatory response induced by urban particulate matter. Methods We compared the pro-inflammatory potential of urban PM collected from New York (NYC) and Baltimore (Balt) with CB, DEP and CFA surrogate PM particles. Eight to ten weeks old BALB/cJ mice were exposed through the airways to particulate material, and markers of airway inflammation were determined. Specifically, we assessed cellular influx, mucus production, lung function, cytokine levels as well as immune cell profiling of the lungs. Results Herein, we demonstrate that exposure to equivalent mass of stand-alone surrogate PM particles like CB, DEP and CFA, fails to induce significant airway inflammatory response seen after similar exposure to urban PMs. Specifically, we observe that PM collected from New York (NYC) and Baltimore city (Balt) triggers a mixed Th2/Th17 response accompanied by eosinophilic and neutrophilic influx, mucus production and airway hyperresponsiveness (AHR). Although the immune profile of NYC and Baltimore PMs are similar, they demonstrate considerable differences in their potency. Baltimore PM induced more robust airway inflammation, AHR, and Th2 cytokine production, possibly due to the greater metal content in Baltimore PM. Conclusions Urban particulate matter with its unique physiochemical properties and heterogeneous composition elicits a mixed Th2/Th17 allergic airway response that is not seen after similar exposures to surrogate PM particles.

Aflatoxin B1 (AFB1) is a potent human and animal hepatocarcinogen. To investigate the effects of aflatoxin on miRNA expression during the initiation phase of carcinogenesis, next-generation sequencing was used to analyze liver tissues from F344 rats exposed to 200 µg/kg per day AFB1 for 4 weeks. A panel of miRNAs was identified that was upregulated with AFB1 treatment compared to controls: rno-miR-434-3p, rno-miR-411-5p, rno-miR-221-3p, rno-miR-127-3p, rno-miR-205, rno-miR-429, rno-miR-34a-5p, rno-miR-181c-3p, rno-miR-200b-3p, and rno-miR-541-5p. Analysis of rat livers exposed to AFB1 plus the chemopreventive triterpenoid CDDO-Im revealed a striking abrogation of this upregulation. These changes were validated by real-time PCR. We also explored the temporal variation in expression of the candidate miRNAs during the 4-week dosing period. Most of the candidate miRNAs were upregulated at week 1 and increased for the duration of AFB1 dosing over the 4-week period. Treatment with CDDO-Im ameliorated these effects at all time points. All candidate miRNAs were detectable in serum from aflatoxin treated animals; however, there was no significant difference in expression for 7 of the 11 miRNAs examined. Exposure to AFB1 upregulated miR-122-5p (5 fold), 34a-5p (13 fold), and 181c-3p (170 fold) compared with controls. The findings from this study give insight into epigenetic changes induced by aflatoxin taking place during the initial step of carcinogenesis. This article is protected by copyright. All rights reserved

Global distribution of hepatocellular carcinomas (HCCs) is dominated by its incidence in developing countries, accounting for >700,000 estimated deaths per year, with dietary exposures to aflatoxin (AFB1) and subsequent DNA adduct formation being a significant driver. Genetic variants that increase individual susceptibility to AFB1-induced HCCs are poorly understood. Herein, it is shown that the DNA base excision repair (BER) enzyme, DNA glycosylase NEIL1, efficiently recognizes and excises the highly mutagenic imidazole ring-opened AFB1-deoxyguanosine adduct (AFB1-Fapy-dG). Consistent with this in vitro result, newborn mice injected with AFB1 show significant increases in the levels of AFB1-Fapy-dG in Neil1-/- vs. wild-type liver DNA. Further, Neil1-/- mice are highly susceptible to AFB1-induced HCCs relative to WT controls, with both the frequency and average size of hepatocellular carcinomas being elevated in Neil1-/- The magnitude of this effect in Neil1-/- mice is greater than that previously measured in Xeroderma pigmentosum complementation group A (XPA) mice that are deficient in nucleotide excision repair (NER). Given that several human polymorphic variants of NEIL1 are catalytically inactive for their DNA glycosylase activity, these deficiencies may increase susceptibility to AFB1-associated HCCs.