Meat-related mutagens/carcinogens in the etiology of colorectal cancer

Towards refining World Cancer Research Fund/American Institute for Cancer Research cancer prevention recommendations for red and processed meat intake: insights from Alberta's Tomorrow Project cohort

Current cancer prevention recommendations advise limiting red meat intake to <500 g/week and avoiding consumption of processed meat, but do not differentiate the source of processed meat. We examined the associations of processed meat derived from red v. non-red meats with cancer risk in a prospective cohort of 26 218 adults who reported dietary intake using the Canadian Diet History Questionnaire. Incidence of cancer was obtained through data linkage with Alberta Cancer Registry with median follow-up of 13·3 (interquartile range (IQR) 5·1) years. Multivariable Cox proportional hazards regression models were adjusted for covariates and stratified by age and sex. The median consumption (g/week) of red meat, processed meat from red meat and processed meat from non-red meat was 267·9 (IQR 269·9), 53·6 (IQR 83·3) and 11·9 (IQR 31·8), respectively. High intakes (4th Quartile) of processed meat from red meat were associated with increased risk of gastrointestinal cancer adjusted hazard ratio (AHR): 1·68 (95 % CI 1·09, 2·57) and colorectal cancers AHR: 1·90 (95 % CI 1·12, 3·22), respectively, in women. No statistically significant associations were observed for intakes of red meat or processed meat from non-red meat. Results suggest that the carcinogenic effect associated with processed meat intake may be limited to processed meat derived from red meats. The findings provide preliminary evidence towards refining cancer prevention recommendations for red and processed meat intake.

Pepper Alkaloids and Processed Meat Intake: Results from a Randomized Trial and the European Prospective Investigation into Cancer and Nutrition (EPIC) Cohort

SCOPE

Processed meat intake has been associated with adverse health outcomes. However, little is known about the type of processed meat more particularly responsible for these effects. This study aims to identify novel biomarkers for processed meat intake.

METHODS AND RESULTS

In a controlled randomized cross-over dietary intervention study, 12 healthy volunteers consume different processed and non-processed meats for 3 consecutive days each. Metabolomics analyses are applied on post-intervention fasting blood and urine samples to identify discriminating molecular features of processed meat intake. Nine and five pepper alkaloid metabolites, including piperine, are identified as major discriminants of salami intake in urine and plasma, respectively. The associations with processed meat intake are tested for replication in a cross-sectional study (n = 418) embedded within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. Three of the serum metabolites including piperine are associated with habitual intake of sausages and to a lesser extent of total processed meat.

CONCLUSION

Pepper alkaloids are major discriminants of intake for sausages that contain high levels of pepper used as ingredient. Further work is needed to assess if pepper alkaloids in combination with other metabolites may serve as biomarkers of processed meat intake.

The Association of Meat Intake With All-Cause Mortality and Acute Myocardial Infarction Is Age-Dependent in Patients With Stable Angina Pectoris

Background: Red and processed meat intake have been associated with increased risk of morbidity and mortality, and a restricted intake is encouraged in patients with cardiovascular disease. However, evidence on the association between total meat intake and clinical outcomes in this patient group is lacking.

Objectives: To investigate the association between total meat intake and risk of all-cause mortality, acute myocardial infarction, cancer, and gastrointestinal cancer in patients with stable angina pectoris. We also investigated whether age modified these associations.

Materials and Methods: This prospective cohort study consisted of 1,929 patients (80% male, mean age 62 years) with stable angina pectoris from the Western Norway B-Vitamin Intervention Trial. Dietary assessment was performed by the administration of a semi-quantitative food frequency questionnaire. Cox proportional hazards models were used to investigate the association between a relative increase in total meat intake and the outcomes of interest.

Results: The association per 50 g/1,000 kcal higher intake of total meat with morbidity and mortality were generally inconclusive but indicated an increased risk of acute myocardial infarction [HR: 1.26 (95% CI: 0.98, 1.61)] and gastrointestinal cancer [1.23 (0.70, 2.16)]. However, we observed a clear effect modification by age, where total meat intake was associated with an increased risk of mortality and acute myocardial infarction among younger individuals, but an attenuation, and even reversal of the risk association with increasing age.

Conclusion: Our findings support the current dietary guidelines emphasizing a restricted meat intake in cardiovascular disease patients but highlights the need for further research on the association between meat intake and health outcomes in elderly populations. Future studies should investigate different types of meat separately in other CVD-cohorts, in different age-groups, as well as in the general population.

Role of Diet in Colorectal Cancer Incidence: Umbrella Review of Meta-analyses of Prospective Observational Studies

IMPORTANCE

Several meta-analyses have summarized evidence for the association between dietary factors and the incidence of colorectal cancer (CRC). However, to date, there has been little synthesis of the strength, precision, and quality of this evidence in aggregate.

OBJECTIVE

To grade the evidence from published meta-analyses of prospective observational studies that assessed the association of dietary patterns, specific foods, food groups, beverages (including alcohol), macronutrients, and micronutrients with the incidence of CRC.

DATA SOURCES

MEDLINE, Embase, and the Cochrane Library were searched from database inception to September 2019.

EVIDENCE REVIEW

Only meta-analyses of prospective observational studies with a cohort study design were eligible. Evidence of association was graded according to established criteria as follows: convincing, highly suggestive, suggestive, weak, or not significant.

RESULTS

From 9954 publications, 222 full-text articles (2.2%) were evaluated for eligibility, and 45 meta-analyses (20.3%) that described 109 associations between dietary factors and CRC incidence were selected. Overall, 35 of the 109 associations (32.1%) were nominally statistically significant using random-effects meta-analysis models; 17 associations (15.6%) demonstrated large heterogeneity between studies (I2 > 50%), whereas small-study effects were found for 11 associations (10.1%). Excess significance bias was not detected for any association between diet and CRC. The primary analysis identified 5 (4.6%) convincing, 2 (1.8%) highly suggestive, 10 (9.2%) suggestive, and 18 (16.5%) weak associations between diet and CRC, while there was no evidence for 74 (67.9%) associations. There was convincing evidence of an association of intake of red meat (high vs low) and alcohol (≥4 drinks/d vs 0 or occasional drinks) with the incidence of CRC and an inverse association of higher vs lower intakes of dietary fiber, calcium, and yogurt with CRC risk. The evidence for convincing associations remained robust following sensitivity analyses.

CONCLUSIONS AND RELEVANCE

This umbrella review found convincing evidence of an association between lower CRC risk and higher intakes of dietary fiber, dietary calcium, and yogurt and lower intakes of alcohol and red meat. More research is needed on specific foods for which evidence remains suggestive, including other dairy products, whole grains, processed meat, and specific dietary patterns.

Effects of Dietary 5'-CMP on Neu5Gc Contents in the Muscle and Viscera of Xiang Pigs

ABSTRACT

In order to reduce the health risks associated with red meat as listed by the World Health Organization, the work presented in this article aimed to elucidate the interaction between 5'-CMP-supplemented feed and N-glycolylneuraminic acid (Neu5Gc) in experimental animals in vivo. 5'-CMP was added to the diet of 90-, 180-, and 270-day-old Xiang pigs, and after 30 days, the Neu5Gc contents, physicochemical parameters, and free amino acid contents of muscle and internal viscera were measured by high-performance liquid chromatography coupled with fluorescence detection. The mechanism by which 5'-CMP affects Neu5Gc contents was investigated using molecular docking. Results show that 5'-CMP significantly decreased the Neu5Gc content in 180-day-old Xiang pigs (P < 0.05) but had no effect on the Neu5Gc contents in 90- and 270-day-old Xiang pigs. Umami amino acids were significantly increased in 180-day-old Xiang pigs. In the 90- and 270-day-old pigs, histidine increased by 10.38 and 17.87%, respectively. The other free amino acids were either reduced or not affected. Moreover, the 5'-CMP-supplemented diet did not affect the physicochemical parameters of the longissimus muscle in the Xiang pigs. 5'-CMP could occupy almost all the sialyltransferase active-site residues but not His302 and showed inhibition of the sialyltransferase activity. The results provided an experimental basis for the subsequent reduction of Neu5Gc in red meat before slaughter.

HIGHLIGHTS

Barbecued desi chicken: an investigation on the impact of polluted milieu upon formation and ingestion of polycyclic aromatic hydrocarbons (PAHs) in commercial versus laboratory barbecued organs along with stochastic cancer risk assessments in people from an industrial district of Punjab, Pakistan

8∑PAHs in 2- and 4-month-old desi chicken organs collected from Faisalabad district, Punjab, Pakistan, were examined via high-performance liquid chromatography (HPLC). Exposure doses (A_VDD) of PAHs with consequential lifetime excess cancer risks (L_tECR) were also estimated in people ingesting laboratory barbecued (L_b) and commercially barbecued (C_b) desi meat organs. The results exposed the presence of 8ΣPAH in 2- and 4-month-old L_b and C_b chicken organs: drumsticks (D_s), breast (B_S), and wings (W_s) (0.45, 3.10, 0.97 ng g^-1; 2.52, 4.31, 1.22 ng g^-1; and 10.09, 15.04, and 9.06 ng g^-1 respectively). BαP was found only in C_b organs with the highest concentrations (5.08 ng g^-1) in B_s. It was above the EU's tolerable limit, while it was not detected in all L_b organs. The lowest level of 8ΣPAH was found in 2-month-old desi W_s. A comparative percentage increase in 8ΣPAH levels between all L_b and C_b organs was found in the range of 1500-2416.67%. L_tECR for males and adults were ranging from 1.35 × E^-13 to 4.49 × E^-5 at different consumption rates with A_VDD ranging from 1.08 E^-6 to 6.01 E^-5. In contrast to 2- and 4- month-old chicken meat, 2-month-old desi meat is better having less PAH load. Comparing different organs, W_s of former one displayed abridged PAH levels. In conclusion, L_b desi meat is less carcinogenic relative to C_b. More PAH levels are due to secondary smoke in C_b samples collected from the metropolitan. Ingestion of L_b 2-month-old desi chicken organs could be safe to dine as compared with 4-month-old desi and C_b organs. Graphical abstract.

Association between meat intake and mortality due to all-cause and major causes of death in a Japanese population

PURPOSE

We examined the association between meat intake and mortality due to all-cause and major causes of death using a population-based cohort study in Japan.

METHODS

87,507 Japanese aged between 45 and 74 years old at 5-year follow-up study were followed for 14.0 years on average. Associations between meat intake and mortality risk were assessed using a Cox proportional hazards model.

RESULTS

A heavy intake of total meat was associated with a higher risk of all-cause mortality relative to the lowest quartile intake in men (Q4: HR,1.18; 95%CIs, 1.06-1.31). A higher intake of total meat was associated with a lower risk of stroke mortality in women (Q2: HR, 0.70; 95%CIs, 0.51-0.94, Q3: HR, 0.68; 95%CIs, 0.50-0.95, Q4: HR, 0.66; 95%CIs, 0.44-0.99). A heavy intake of red meat was also associated with all-cause mortality (Q4: HR, 1.13; 95%CIs, 1.02-1.26) and heart disease mortality (Q4: HR, 1.51; 95%CIs, 1.11-2.06) in men but not in women. Heavy intake of chicken was inversely associated with cancer mortality in men.

CONCLUSIONS

Heavy intakes of total and red meat were associated with an increase in all-cause and heart disease mortality in men, while total meat intake was associated with a lower risk of stroke mortality in women.

Association between meat and saturated fatty acid intake and lung cancer risk: The Japan Public Health Center-based prospective study

Red meat or saturated fatty acid (SFA) intake has been reported to increase lung cancer (LC) risk in several western countries. However, in Asia, studies on the relationship between meat and SFA intake with LC incidence are still relatively insufficient, and their conclusions are inconsistent. We investigated the association of meat and SFA intake with LC incidence in a population-based prospective cohort study in Japan. Cox regression was used to estimate the hazard ratio (HR) and 95% confidence interval (CI) for LC risk according to meat intake and SFA intake. A total of 73 187 participants (32 934 men and 40 253 women) aged 45 to 74 years participated in our study. During the follow-up period of 1 151 839 person-years (median, 16.0 year) from 1995 to 2013 for Cohort I and from 1998 to 2013 for Cohort II, 1315 (901 men and 414 women) newly diagnosed cases of LC were identified. In men, we found an adverse association between total red meat intake (HR and 95% CI: 1.25 [1.02-1.53]; P_trend = .008) and LC risk. Additionally, borderline statistically significant elevated risks of LC were seen with high intake of unprocessed red meat and processed red meat. However, no positive association between total red meat intake and LC risk was observed in women. In contrast, poultry and fish intake were not associated with LC risk in either men or women. We concluded that a high total intake of total red meat was associated with moderately elevated LC risk in men.

Basics to advances in nanotherapy of colorectal cancer

Colorectal cancer (CRC) is the third most common cancer existing across the globe. It begins with the formation of polyps leading to the development of metastasis, especially in advanced stage patients, who necessitate intensive chemotherapy that usually results in a poor response and high morbidity owing to multidrug resistance and severe untoward effects to the non-cancerous cells. Advancements in the targeted drug delivery permit the targeting of tumor cells without affecting the non-tumor cells. Various nanocarriers such as liposomes, polymeric nanoparticles, carbon nanotubes, micelles, and nanogels, etc. are being developed and explored for effective delivery of cytotoxic drugs to the target site thereby enhancing the drug distribution and bioavailability, simultaneously subduing the side effects. Moreover, immunotherapy for CRC is being explored for last few decades. Few clinical trials have even potentially benefited patients suffering from CRC, still immunotherapy persists merely an experimental alternative. Assessment of the ongoing and completed trials is to be warranted for effective treatment of CRC. Scientists are paying efforts to develop novel carrier systems that may enhance the targeting potential of low therapeutic index chemo- and immune-therapeutics. Several preclinical studies have revealed the superior efficacy of nanotherapy in CRC as compared to conventional approaches. Clinical trials are being recruited to ascertain the safety and efficacy of CRC therapies. The present review discourses in a nutshell the molecular interventions including the genetics, signaling pathways involved in CRC, and advances in various strategies explored for the treatment of CRC with a special emphasis on nanocarriers based drug targeting.

High Consumption of Red Meat Is Associated with Excess Mortality Among African-American Women

BACKGROUND

Red meat is a rich source of nutrients but is typically high in saturated fats. Carcinogenic chemicals can be formed during cooking and processing. Little is known about the relation of red meat consumption to mortality in African Americans (AAs), a group with excess mortality and high consumption of red meat relative to whites.

OBJECTIVE

Our objective was to assess the association between red meat consumption and mortality in AA women.

METHODS

The Black Women's Health Study (BWHS) is a prospective cohort study of AA women across the USA who completed health questionnaires at enrollment in 1995 (median age 38 y, median BMI 27.9 kg/m2) and every 2 y thereafter. The analyses included 56,314 women who completed a validated FFQ and were free of cardiovascular disease and cancer at baseline in 1995. Exposures were total red meat, processed red meat, and unprocessed red meat consumption. Outcomes were all-cause and cause-specific mortality. Cox proportional hazards models with control for age, socioeconomic status, lifestyle factors, medical history, and dietary factors were used to estimate HRs with 95% CIs.

RESULTS

During 22 y of follow-up through to 2017, we identified 5054 deaths, which included 1354 cardiovascular deaths and 1801 cancer deaths. The HR for all-cause mortality was 1.47 (95% CI: 1.33, 1.62) for the highest quintile of total red meat consumption relative to the lowest. Each 1 serving/d increase in red meat consumption was associated with a 7% (95% CI: 5%, 9%) increased risk of all-cause mortality. Red meat consumption was also associated with increased cardiovascular mortality, but not with cancer mortality. Results were similar for the consumption of processed and unprocessed red meat.

CONCLUSIONS

Red meat consumption is associated with increased all-cause and cardiovascular mortality among AA women.

Association between Neu5Gc carbohydrate and serum antibodies against it provides the molecular link to cancer: French NutriNet-Santé study

BACKGROUND

High consumption of red and processed meat is commonly associated with increased cancer risk, particularly colorectal cancer. Antibodies against the red meat-derived carbohydrate N-glycolylneuraminic acid (Neu5Gc) exacerbate cancer in "human-like" mice. Human anti-Neu5Gc IgG and red meat are both independently proposed to increase cancer risk, yet how diet affects these antibodies is largely unknown.

METHODS

We used world global data to demonstrate that colorectal cancer incidence and mortality are associated with increased national meat consumption. In a well-defined large cohort, we used glycomics to measure daily Neu5Gc intake from red meat and dairy, and investigated serum as well as affinity-purified anti-Neu5Gc antibodies. Based on 24-h dietary records, daily Neu5Gc intake was calculated for 19,621 subjects aged ≥ 18 years of the NutriNet-Santé study. Serum and affinity-purified anti-Neu5Gc antibodies were evaluated by ELISA and glycan microarrays in representative 120 individuals, each with at least eighteen 24-h dietary records (aged 45-60, Q1-Q4; aged > 60, Q1 and Q4; 10 men/women per quartile).

RESULTS

We found that high-Neu5Gc diet, gender, and age affect the specificity, levels, and repertoires of anti-Neu5Gc IgG immune responses, but not their affinity. Men consumed more Neu5Gc than women, mostly from red meat (p = 0.0015), and exhibited higher overall serum anti-Neu5Gc IgG levels by ELISA (3.94 ng/μl versus 2.22 ng/μl, respectively; p = 0.039). Detailed glycan microarray analysis against 56 different glycans revealed high Neu5Gc-specificity with increased anti-Neu5Gc IgG and altered repertoires, associated with higher consumption of Neu5Gc from red meat and cow dairy. Affinity purification of serum anti-Neu5Gc antibodies revealed increased levels and biased array repertoire patterns, without an increase in antibody affinity, in individuals consuming higher Neu5Gc levels. Furthermore, in a high-meat diet, antibody diversity patterns on glycan microarrays shifted towards Neu5Gcα3-linked glycans, increasing the α3/α6-glycans ratio score.

CONCLUSIONS

We found a clear link between the levels and repertoire of serum anti-Neu5Gc IgG and Neu5Gc intake from red meat and dairy. These precise rational methodologies allowed to develop a Gcemic index to simplify the assessment of Neu5Gc in foods that could potentially be adapted for dietary recommendations to reduce cancer risk.

Colon Transcriptomics Reveals Sex-Dependent Metabolic Signatures in Response to 2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine Treatment in C57BL/6N Mice

Diets high in red meats, particularly meats cooked at high temperature, increase the risk of colon cancer due to a production of heterocyclic aromatic amines (HAAs). Of the identified HAAs, 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) is the most mass abundant colon carcinogen in charred meat or fish. Here, we comprehensively examined sex-dependent colon transcriptome signatures in response to PhIP treatment to identify biological discrepancies. Eight-week-old male and female C57BL/6N mice were intraperitoneally injected with PhIP (10 mg/kg of body weight) and colon tissues were harvested 24 h after PhIP injection, followed by colon transcriptomics analysis. A list of differentially expressed genes (DEGs) was utilized for computational bioinformatic analyses. Specifically, overrepresentation test using the Protein Analysis Through Evolutionary Relationships tool was carried out to annotate sex-dependent changes in transcriptome signatures after PhIP treatment. Additionally, the most significantly affected canonical pathways by PhIP treatment were predicted using the Ingenuity Pathway Analysis. As results, male and female mice presented different metabolic signatures in the colon transcriptome. In the male mice, oxidative phosphorylation in the mitochondrial respiratory chain was the pathway impacted the most; this might be due to a shortage of ATP for DNA repair. On the other hand, the female mice showed concurrent activation of lipolysis and adipogenesis. The present study provides the foundational information for future studies of PhIP effects on underlying sex-dependent mechanisms.

Hepatic transcriptomics analysis reveals that fructose intervention down-regulated xenobiotics-metabolising enzymes through aryl hydrocarbon receptor signalling suppression in C57BL/6N mice

For decades, fructose intake has been recognised as an environmental risk for metabolic syndromes and diseases. Here we comprehensively examined the effects of fructose intake on mice liver transcriptomes. Fructose-supplemented water (34 %; w/v) was fed to both male and female C57BL/6N mice at their free will for 6 weeks, followed by hepatic transcriptomics analysis. Based on our criteria, differentially expressed genes (DEG) were selected and subjected to further computational analyses to predict key pathways and upstream regulator(s). Subsequently, predicted genes and pathways from the transcriptomics dataset were validated via quantitative RT-PCR analyses. As a result, we identified eighty-nine down-regulated and eighty-eight up-regulated mRNA in fructose-fed mice livers. These DEG were subjected to bioinformatics analysis tools in which DEG were mainly enriched in xenobiotic metabolic processes; further, in the Ingenuity Pathway Analysis software, it was suggested that the aryl hydrocarbon receptor (AhR) is an upstream regulator governing overall changes, while fructose suppresses the AhR signalling pathway. In our quantitative RT-PCR validation, we confirmed that fructose suppressed AhR signalling through modulating expressions of transcription factor (AhR nuclear translocator; Arnt) and upstream regulators (Ncor2, and Rb1). Altogether, we demonstrated that ad libitum fructose intake suppresses the canonical AhR signalling pathway in C57BL/6N mice liver. Based on our current observations, further studies are warranted, especially with regard to the effects of co-exposure to fructose on (1) other types of carcinogens and (2) inflammation-inducing agents (or even diets such as a high-fat diet), to find implications of fructose-induced AhR suppression.

10-Year Trends in Dietary Intakes in the High- and Low-Risk Areas for Esophageal Cancer: A Population-Based Ecological Study in Northern Iran

BACKGROUND

We assessed dietary intakes in the high- and low-risk areas for esophageal cancer (EC) in Golestan province, Northern Iran.

METHODS

Considering the EC rates, Golestan province was divided into high- and low-risk regions. Data on households’ food consumption were obtained from the Statistical Center of Iran. We used multivariable logistic regression to assess the relationships between consumption of main food and EC risk. Adjusted odds ratios (aOR) were calculated. Joint point program was used for time trend analysis and average annual percent changes (AAPC) were reported.

RESULTS

Overall, 11910 households were recruited during 2006-2015. 4710 (39.5%) households were enrolled from the high-risk region. There were significant positive relationships between high consumption of sweets (aOR = 1.62; 95% CI: 1.24-2.10), oil/fat (aOR = 1.36; 95% CI: 1.04-1.79), and red meat (aOR = 1.33; 95% CI: 1.07-1.65) with EC risk. We found significant negative relationships between high consumption of dairy products (aOR = 0.62; 95% CI: 0.46-0.82), vegetables (aOR = 0.66; 95% CI: 0.50-0.87) and fruit (aOR = 0.72; 95% CI: 0.55-0.95) with the risk of EC. Time trend analysis showed a significant increasing trend in the proportions of households with low consumption of vegetables (AAPC = 4.71, p = 0.01) and dairy products (AAPC = 5.26, p = 0.02) in the low-risk region for EC.

CONCLUSION

Dietary intakes may be important etiological factors for EC in Northern Iran. Further studies are warranted to assess the role of dietary factors in this high-risk population.

Association between protein-rich dietary patterns and anthropometric measurements among children aged 6 years

AIM

The associations between types of dietary protein intake and child anthropometric measurements have not been fully studied. Therefore, we examined dietary protein pattern in relation to anthropometric indicators among 6-year-old children.

METHODS

We carried out a cross-sectional study of 788 randomly selected children from health centres in Tehran, Iran. Dietary intake was assessed using a food frequency questionnaire completed by the mothers. Anthropometric measurements were based on standard protocols. Principle component analysis was performed to identify different dietary protein patterns. We used multivariate logistic regression to evaluate how these patterns were associated with child anthropometry.

RESULTS

Three dietary protein patterns were identified: pattern 1 (rich in red and processed meats, dairy products and eggs), pattern 2 (rich in fish and poultry) and pattern 3 (rich in soy and legumes). After adjusting for potential confounders (energy intake, socioeconomic status and physical activity), being in the third compared to the first tertiles of pattern 2 was associated with increased (OR = 1.57; 95% CI: 1.09-2.27; P = .01) and decreased (OR = 0.54; 95% CI: 0.32-0.92; P = .02) risk of overweight/obesity and underweight/wasting, respectively. There was no association between other dietary patterns and risk of overweight/obesity or underweight/wasting.

CONCLUSIONS

The present study showed inverse association between the fish/white meat pattern and underweight/wasting and also a positive association between higher fish/white meat protein intake and higher risk of overweight/obesity. Further studies are needed to confirm these results.

Development of the anti-cancer food scoring system 2.0: Validation and nutritional analyses of quantitative anti-cancer food scoring model

BACKGROUND/OBJECTIVES

We have previously designed the anti-cancer food scoring model (ACFS) 1.0, an evidence-based quantitative tool analyzing the anti-cancer or carcinogenic potential of diets. Analysis was performed using simple quantitative indexes divided into 6 categories (S, A, B, C, D, and E). In this study, we applied this scoring model to wider recipes and evaluated its nutritional relevance.

MATERIALS/METHODS

National or known regional databases were searched for recipes from 6 categories: Korean out-dining, Korean home-dining, Western, Chinese, Mediterranean, and vegetarian. These recipes were scored using the ACFS formula and the nutrition profiles were analyzed.

RESULTS

Eighty-eight international recipes were analyzed. All S-graded recipes were from vegetarian or Mediterranean categories. The median code values of each category were B (Korean home-dining), C (Korean out-dining), B (Chinese), A (Mediterranean), S (vegetarian), and D (Western). The following profiles were correlated (P < 0.05) with ACFS grades in the univariate trend analysis: total calories, total fat, animal fat, animal protein, total protein, vitamin D, riboflavin, niacin, vitamin B₁₂, pantothenic acid, sodium, animal iron, zinc, selenium, and cholesterol (negative trends), and carbohydrate rate, fiber, water-soluble fiber, vitamin K, vitamin C, and plant calcium (positive trends). Multivariate analysis revealed that animal fat, animal iron, and niacin (negative trends) and animal protein, fiber, and vitamin C (positive trends) were statistically significant. Pantothenic acid and sodium showed non-significant negative trends (P < 0.1), and vitamin B₁₂ showed a non-significant positive trend.

CONCLUSION

This study provided a nutritional basis and extended the utility of ACFS, which is a bridgehead for future cancer-preventive clinical trials using ACFS.

Evaluation of Tobacco Smoke and Diet as Sources of Exposure to Two Heterocyclic Aromatic Amines for the U.S. Population: NHANES 2013-2014

BACKGROUND

Heterocyclic aromatic amines (HAA) are a group of hazardous substances produced during combustion of tobacco or high-temperature cooking of meats. 2-Amino-9H-pyrido[2,3-b]indole (AαC) is a major carcinogenic HAA in tobacco smoke.

METHODS

Urinary AαC, used as a marker of AαC exposure, was analyzed on spot urine samples from adult participants of the 2013-2014 cycle of the National Health and Nutrition Examination Survey (N = 1,792). AαC was measured using isotope-dilution liquid chromatography-tandem mass spectrometry. Exclusive combusted tobacco smokers were differentiated from nonusers of tobacco products through both self-report and serum cotinine data.

RESULTS

Among exclusive smokers, sample-weighted median urinary AαC was 40 times higher than nonusers. Sample-weighted regression models showed that urinary AαC increased significantly with serum cotinine among both exclusive tobacco users and nonusers with secondhand smoke exposure. Among nonusers, eating beef cooked at high temperature was associated with a significant increase in urinary AαC, whereas consuming vegetables was associated with decreased AαC. In addition, smoking one-half pack of cigarettes per day was associated with a significant increase of 23.6 pg AαC/mL calculated at geometric mean of AαC, controlling for potential confounders. In comparison, increase in AαC attributable to consuming the 99th percentile of beef cooked at high temperature was 0.99 pg AαC/mL.

CONCLUSIONS

Both exclusive smokers and nonusers of tobacco in the general U.S. population are exposed to AαC from tobacco smoke, with additional, lesser contributions from certain dietary components.

IMPACT

AαC is an important biomarker that is associated with tobacco smoke exposure.

Doneness preferences, meat and meat-derived heterocyclic amines intake, and N-acetyltransferase 2 polymorphisms: association with colorectal adenoma in Japanese Brazilians

Intake of heterocyclic amines (HCAs) and other mutagenic compounds formed during cooking has been hypothesized to be responsible for the positive association observed between red meat and colorectal cancer. We evaluated whether well-done/very well-done preferences for various meat and fish items, higher intakes of meat and fish, and meat-derived and fish-derived HCA are associated with the risk of colorectal adenoma (CRA) in a Japanese-Brazilian population. We selected 302 patients with adenoma and 403 control individuals who underwent total colonoscopy between 2007 and 2013, and collected information on aspects of meat intake using a detailed questionnaire. We also estimated HCA intake of the study participants using an HCA database that matched the cooking methods of this population. Latent class analysis on the basis of response to doneness preferences for different cooking methods of commonly consumed meat and fish items identified four distinct subgroups. Compared with the subgroup characterized by a preference for rare/medium well-done cooking for most meat and fish items, the odds ratio of CRA for the well-done/very well-done preference subgroup was 1.19 (95% confidence interval: 0.51-2.75). High intake of mixed-meat dishes was suggestively associated inversely with CRA, whereas a high intake of poultry was associated positively with CRA. No clear association with intake of total or specific HCAs and no effect modification by N-acetyltransferase 2 acetylation genotype were observed. We found no statistically significant associations between meat and HCA intake and CRA. These findings do not support a positive association between meat and meat-derived HCA intake and the risk of CRA.

Biomarkers of meat and seafood intake: an extensive literature review

Meat, including fish and shellfish, represents a valuable constituent of most balanced diets. Consumption of different types of meat and fish has been associated with both beneficial and adverse health effects. While white meats and fish are generally associated with positive health outcomes, red and especially processed meats have been associated with colorectal cancer and other diseases. The contribution of these foods to the development or prevention of chronic diseases is still not fully elucidated. One of the main problems is the difficulty in properly evaluating meat intake, as the existing self-reporting tools for dietary assessment may be imprecise and therefore affected by systematic and random errors. Dietary biomarkers measured in biological fluids have been proposed as possible objective measurements of the actual intake of specific foods and as a support for classical assessment methods. Good biomarkers for meat intake should reflect total dietary intake of meat, independent of source or processing and should be able to differentiate meat consumption from that of other protein-rich foods; alternatively, meat intake biomarkers should be specific to each of the different meat sources (e.g., red vs. white; fish, bird, or mammal) and/or cooking methods. In this paper, we present a systematic investigation of the scientific literature while providing a comprehensive overview of the possible biomarker(s) for the intake of different types of meat, including fish and shellfish, and processed and heated meats according to published guidelines for biomarker reviews (BFIrev). The most promising biomarkers are further validated for their usefulness for dietary assessment by published validation criteria.

Syringol metabolites as new biomarkers for smoked meat intake

BACKGROUND

Processed meat intake is associated with a higher risk of colorectal and stomach cancers, coronary artery disease, and type 2 diabetes and with higher mortality, but the estimation of intake of different processed meat products in this heterogeneous food group in epidemiological studies remains challenging.

OBJECTIVE

This work aimed at identifying novel biomarkers for processed meat intake using metabolomics.

METHODS

An untargeted, multi-tiered metabolomics approach based on LC-MS was applied to 33 meat products digested in vitro and secondly to urine and plasma samples from a randomized crossover dietary intervention in which 12 volunteers consumed successively 3 processed meat products (bacon, salami, and hot dog) and 2 other foods used as controls, over 3 consecutive days. The putative biomarkers were then measured in urine from 474 subjects from the European Prospective Investigation into Cancer and Nutrition (EPIC) cross-sectional study for which detailed 24-h dietary recalls and FFQs were available.

RESULTS

Syringol and 4 derivatives of syringol were found to be characteristic of in vitro digests of smoked meat products. The same compounds present as sulfate esters in urine increased at 2 and 12 h after consumption of smoked meat products (hot dog, bacon) in the intervention study. The same syringol sulfates were also positively associated with recent or habitual consumption of smoked meat products in urine samples from participants of the EPIC cross-sectional study. These compounds showed good discriminative ability for smoked meat intake with receiver operator characteristic areas under the curve ranging from 0.78 to 0.86 and 0.74 to 0.79 for short-term and habitual intake, respectively.

CONCLUSIONS

Four novel syringol sulfates were identified as potential biomarkers of smoked meat intake and may be used to improve assessment of smoked meat intake in epidemiological studies. This trial was registered at clinicaltrials.gov as NCT03354130.

Relevance of physical function in the association of red and processed meat intake with all-cause, cardiovascular, and cancer mortality

BACKGROUND AND AIMS

Intake of red and processed meat has been associated with a higher risk of morbidity and mortality; it is unknown whether these associations are modified by overall physical health. This study examined the associations of red and processed meat consumption with all-cause, cardiovascular, and cancer mortality and investigated whether markers of physical function modified the associations.

METHODS AND RESULTS

This observational cohort study used UK Biobank data derived from 419,075 participants free from cancer and cardiovascular disease. Cox models assessed the association of red and processed meat consumption (obtained from a baseline food frequency questionnaire) with mortality, adjusted for potential confounders. Objectively measured handgrip strength and self-reported walking pace were used as interaction terms. The median age was 57 (interquartile range, 49-63) years and 54.9% were women. Over 7 years of follow-up, 8586 all-cause, 1660 cardiovascular, and 4812 cancer deaths occurred. Each additional serving per week of red and processed meat was associated with a hazard ratio (HR) of 1.037 (95% CI: 1.028-1.047) for all-cause; 1.030 (1.009-1.051) for cardiovascular; and 1.029 (1.016-1.042) for cancer mortality. The association of red and processed meat consumption was modified by walking pace, with brisk walkers having the lowest risk per additional serving for all-cause and cancer mortality (HR 1.025; 1.006-1.045 and 1.015; 0.990-1.040, respectively); no interaction was observed for handgrip strength.

CONCLUSION

The known risk of mortality associated with red and processed meat consumption may be lower in those with high physical function.

Knowledge, attitudes and eating habits red and processed meat among gym users: a cross-sectional survey

Aims:

In 2015, the International Agency for Research on Cancer (IARC) classified red meat (RM) and processed meat (PM) intakes as ‘probably carcinogenic’ and ‘carcinogenic’ to humans, respectively. The aim of the study was to evaluate eating behaviours and knowledge on the potential risks of RM-PM consumption among gym users.

Methods:

In 2018, a cross-sectional survey was conducted in 20 gyms in Turin using a 48-item questionnaire assessing sociodemographic, sports, dietary information and knowledge about RM-PM (sample size = 298). Multivariable logistic and linear regressions were performed. The significance level was p ⩽ 0.05.

Results:

Around 75% of the sample consumed RM and PM at least once a week, with an average of 240.55 ± 435.99 g and 106.50 ± 157.88 g consumed weekly, respectively. Only 7.69% exceeded 700 g of raw RM weekly. Females, those with higher education, those who practise sport outside gyms and those who declared to practise sport to stay healthy, declared to consume less RM. Those who practise sport at a competitive level, those who are on a diet for athletic needs, those with higher body mass index (BMI) and those who consume more eggs and alcohol had a higher RM intake. The association with PM consumption was negative for females and positive for those living without a partner. The likelihood of answering incorrectly to one of the knowledge outcomes was lower for those who had a healthcare-related background and declared to practise sport to stay healthy, while it was higher for participants who stated to have a sport-related background, to be on a diet to lose weight, to read rarely/never the RM-PM nutrition labels and to consume <400 g of fruit and vegetables daily.

Conclusions:

Given the relatively low knowledge of the potential risks of RM-PM consumption, it would be advisable to implement campaigns specifically focused on male athletes and people with lower socioeconomic status, in order to raise awareness about this topic.

Primary Outcomes of a Randomized Controlled Crossover Trial to Explore the Effects of a High Chlorophyll Dietary Intervention to Reduce Colon Cancer Risk in Adults: The Meat and Three Greens (M3G) Feasibility Trial

Preclinical and observational research suggests green leafy vegetables (GLVs) may reduce the risk of red meat (RM)-induced colonic DNA damage and colon cancer (CC). We sought to determine the feasibility of a high GLV dietary intervention in adults with an increased risk of CC (NCT03582306) via a 12-week randomized controlled crossover trial. Participants were randomized to immediate or delayed (post-4-week washout) intervention groups. During the 4-week intervention period, participants were given frozen GLVs and counseled to consume one cooked cup equivalent daily. The primary outcomes were: accrual—recruiting 50 adults in 9 months; retention—retaining 80% of participants at completion; and adherence—meeting GLV intake goals on 90% of days. Adherence data were collected twice weekly and 24-h dietary recalls at each time point provided nutrient and food group measures. The Food Acceptability Questionnaire (FAQ) was completed to determine acceptability. On each of the four study visits, anthropometrics, stool, saliva, and blood were obtained. Fifty adults were recruited in 44 days. Participants were 48 ± 13 years of age, 62% female, and 80% Caucasian, with an average BMI at screening of 35.9 ± 5.1. Forty-eight (96%) participants were retained and completed the study. During the intervention phase, participants consumed GLVs on 88.8% of days; the adherence goal of one cup was met on 73.2% of days. Dietary recall-derived Vitamin K and GLVs significantly increased for all participants during the intervention periods. Overall satisfaction did not differ between intervention and control periods (p = 0.214). This feasibility trial achieved accrual, retention and acceptability goals, but fell slightly short of the benchmark for adherence. The analysis of biological specimens will determine the effects of GLVs on gut microbiota, oxidative DNA damage, and inflammatory cytokines.

Tumour growth activation by the central nervous system-An integrative theory of cancer

The currently recognized mechanisms of the biology of cancer are not yet enough to explain the high incidence of the disease in industrialized countries. Survival and proliferation of cancer cells demand a well-orchestrated combination of functional capabilities, or hallmarks, which requires complex signalling networks that often exceed the tumour boundaries. Based on latest research on environmental health and aiming to provide cancer with a coherent set of organizing principles, we propose an integrative model of carcinogenesis founded on tumour growth activation by the central nervous system as an adaptive, allostatic response to both environmental and emotional challenges. In this way, chronicity of physical as well as psychological stressors may be directly involved in cancer genesis and progression, after an early inflammatory stage. The model also contemplates accidental activation of the tumour growth programme following direct DNA damage, but as a rare event that does not account for most cancers in humans. Bodily and cellular mechanisms designed to facilitate tumorigenesis may include exacerbation of the sympathetic activity, overexpression of membrane ion channels, promotion of selected mutations and methylations, degradation of the mitochondria and reprogramming of adult stem cells.

A Prospective Analysis of Red and Processed Meat Consumption and Risk of Colorectal Cancer in Women

BACKGROUND

Red and processed meats have been implicated as risk factors in the development of colorectal cancer in U.S. women, but associations with cooking practices are less well established.

METHODS

Data are from the Sister Study, a cohort of women ages 35 to 74 years from the United States and Puerto Rico who have a sister diagnosed with breast cancer. Red and processed meat consumption, meat cooking practices, and intake of common meat products were collected at baseline using self-administered questionnaires (N = 48,704). Multivariable HRs (HR_adj) and 95% confidence intervals (95% CI) were estimated.

RESULTS

During a median 8.7 years' follow-up (range <1-12.7 years), 216 colorectal cancer cases were diagnosed. In categorical analyses, an increased risk of colorectal cancer was seen in the highest quartile of processed meat consumption compared with the lowest [HR_adj = 1.52 (95% CI, 1.01-2.30); P _trend = 0.02], and for specific meat products, including breakfast sausages [HR_adj = 1.85 (95% CI, 1.30-2.64)] and bacon [HR_adj = 1.46 (95% CI, 1.01-2.11)]. The HR_adj for the highest quartile of red meat consumption was 1.04 (95% CI, 0.68-1.60), and little evidence of association was observed for cooking practices or doneness of red meat. We observed positive associations with specific red meat products when cooking methods were considered, for example, grilled/barbequed steaks [HR_adj = 2.23 (95% CI, 1.20-4.14)] and hamburgers [HR_adj = 1.98 (95% CI, 1.00-3.91)].

CONCLUSIONS

Higher reported daily intake of processed meats and consumption of barbecued/grilled red meat products were associated with increased risk of colorectal cancer in women.

IMPACT

Variability in colorectal risk risk by meat type and cooking method should be considered when evaluating meat consumption.

Meat subtypes and colorectal cancer risk: A pooled analysis of 6 cohort studies in Japan

Red meat and processed meat have been suggested to increase risk of colorectal cancer (CRC), especially colon cancer. However, it remains unclear whether these associations differ according to meat subtypes or colon subsites. The present study addressed this issue by undertaking a pooled analysis of large population-based cohort studies in Japan: 5 studies comprising 232 403 participants (5694 CRC cases) for analysis based on frequency of meat intake, and 2 studies comprising 123 635 participants (3550 CRC cases) for analysis based on intake quantity. Study-specific hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using the Cox proportional hazards model and then pooled using the random effect model. Comparing the highest vs lowest quartile, beef intake was associated with an increased risk of colon cancer in women (pooled HR 1.20; 95% CI, 1.01-1.44) and distal colon cancer (DCC) risk in men (pooled HR 1.30; 95% CI, 1.05-1.61). Frequent intake of pork was associated with an increased risk of distal colon cancer in women (pooled HR 1.44; 95% CI, 1.10-1.87) for "3 times/wk or more" vs "less than 1 time/wk". Frequent intake of processed red meat was associated with an increased risk of colon cancer in women (pooled HR 1.39; 95% CI, 0.97-2.00; P trend = .04) for "almost every day" vs "less than 1 time/wk". No association was observed for chicken consumption. The present findings support that intake of beef, pork (women only), and processed red meat (women only) might be associated with a higher risk of colon (distal colon) cancer in Japanese.

Consumption of meat, traditional and modern processed meat and colorectal cancer risk among the Moroccan population: A large-scale case-control study

The current study aimed to investigate the relationship between red and white meat subtypes, processed meat (divided into traditional "Khlii, Kaddid" and industrially processed meat) and colorectal cancer (CRC) risk, considering CRC subsites, in Moroccan adults. A case-control study was conducted including 2,906 matched case-control pairs recruited from the five largest university hospitals in Morocco. Dietary data were collected through a validated Food Frequency Questionnaire (FFQ). Multivariable odds ratios (OR) and 95% confidence intervals (CI), for the association of CRC risk with meat consumption (high vs. low intake), were estimated using conditional logistic regression models, adjusted for relevant confounding variables. Overall, consumption of red meat was positively associated with colon cancer and CRC risk (OR = 1.23, 95% CI = 1.05-1.44; OR = 1.14, 95% CI = 1.02-1.27), respectively. In contrast, no significant association was observed between the consumption of red meat and rectal cancer risk (OR = 1.05, 95% = 0.90-1.23). Interestingly, while processed meat from industrial processes was positively associated with colon cancer, rectal cancer and CRC (OR = 1.61, 95% CI = 1.27-2.04; OR = 1.73, 95% CI = 1.34-2.23; OR = 1.67, 95% CI = 1.41-1.98), processed meat prepared using traditional methods was inversely associated with colon cancer and CRC risk (OR = 0.74, 95% CI = 0.57-0.98; OR = 0.77, 95% CI = 0.64-0.93), respectively. Furthermore, positive associations were observed between poultry intake and colon cancer risk among men (OR = 1.27, 95% CI = 1.01-1.59). Our study showed similar associations between the consumption of red meat and CRC risk in Morocco as in developed countries, while inverse associations were found for traditionally processed meat products. This is the first study to investigate the differential effects of traditional vs. westernized processed meat products in a developing country. Other studies are needed to confirm these findings and to understand the physiological pathways underlying these associations.

Effects of three products from Antarctic krill on the nitrogen balance, growth, and antioxidation status of rats

A few studies conducted over the past few decades have demonstrated the health benefits of a diet rich in marine products, but limited studies have investigated the effects of different krill products on the nitrogen balance and their potential health benefits. In our study, after a 14-day acclimation period, 50 female Sprague-Dawley rats were randomly assigned to five groups, each of which was fed a different diet, for 28 days. We then evaluated the effect of krill protein complex (KPC), krill powder, and defatted krill powder on the nitrogen balance, growth, and antioxidant activity through analyses of MDA, CAT, GSH-Px, and T-SOD. An in vivo analysis suggested that the nitrogen retention rate, protein digestibility, and bioutilization of krill products were equal to those of casein. Moreover, the KPC diet resulted in the highest nitrogen intake and retention among the groups, and the biological value and net protein utilization obtained with KPC were higher than those obtained with defatted krill powder, which was consistent with the weight gains observed for these two groups. The hematological test also showed that KPC contributed to the production of functional proteins in the body. The antioxidant activity analysis indicated that higher GSH-Px and T-SOD activities were obtained with krill products and KPC, respectively, compared with casein. The results from this study suggested that krill proteins could promote growth and improve the antioxidant status of an organism. Although further studies on the safety of krill products for human consumption are needed, this work provides insights into the use of krill proteins as a potential substitute for other proteins and restructured foods.

Red Meat-Derived Nitroso Compounds, Lipid Peroxidation Products and Colorectal Cancer

About 20 years ago, the research group of Sheila Anne Bingham in Cambridge, UK, showed for the first time that volunteers consuming large amounts of red meat excrete high amounts of nitroso compounds via feces. In the meantime, it has been demonstrated that heme leads to the enhanced formation of nitroso compounds in the gastrointestinal tract and that the main nitroso compounds formed in the gastrointestinal tract are S-nitrosothiols and the nitrosyl heme. Moreover, it has been postulated that these endogenously formed nitroso compounds may alkylate guanine at the O⁶-position, resulting in the formation of the promutagenic DNA lesions O⁶-methylguanine and O⁶-carboxymethylguanine, which, if not repaired (in time), could lead to gene mutations and, subsequently to the development of colorectal cancer. Alternatively, it has been postulated that heme iron could contribute to colorectal carcinogenesis by inducing lipid peroxidation. In the present review, the evidence supporting the above-mentioned hypotheses will be presented.

Association Between Intake of Red and Processed Meat and Survival in Patients With Colorectal Cancer in a Pooled Analysis

BACKGROUND & AIMS

Red and processed meat intake is associated with colorectal cancer (CRC) incidence, but it is not clear if intake is associated with patient survival after diagnosis.

METHODS

We pooled data from 7627 patients with stage I-IV CRC from 10 studies in the International Survival Analysis in Colorectal Cancer Consortium. Cox proportional hazards regression models were used to evaluate the associations of intake of red and processed meat before diagnosis with overall and CRC-specific survival.

RESULTS

Among 7627 patients with CRC, 2338 died, including 1576 from CRC, over a median follow-up time of 5.1 years. In multivariable-adjusted analyses, higher intake of red or processed meat was not associated with overall survival of patients with stage I-III CRC: Q4 vs Q1 red meat hazard ratio [HR], 1.08 (95% CI, 0.93-1.26) and Q4 vs Q1 processed meat HR, 1.10 (95% CI, 0.93-1.32) or with CRC-specific survival: Q4 vs Q1 red meat HR, 1.09 (95% CI, 0.89-1.33) and Q4 vs Q1 processed meat HR, 1.11 (95% CI, 0.87-1.42). Results were similar for patients with stage IV CRC. However, patients with stage I-III CRC who reported an intake of processed meat above the study-specific medians had a higher risk of death from any cause (HR, 1.12; 95% CI, 1.01-1.25) than patients who reported eating at or less than the median.

CONCLUSION

In this large consortium of CRC patient cohorts, intake of red and processed meat before a diagnosis of CRC was not associated with shorter survival time after diagnosis, although a possible weak adverse association cannot be excluded. Studies that evaluate dietary data from several time points before and after cancer diagnosis are required to confirm these findings.

ABC Transporters: Regulation and Association with Multidrug Resistance in Hepatocellular Carcinoma and Colorectal Carcinoma

For most cancers, the treatment of choice is still chemotherapy despite its severe adverse effects, systemic toxicity and limited efficacy due to the development of multidrug resistance (MDR). MDR leads to chemotherapy failure generally associated with a decrease in drug concentration inside cancer cells, frequently due to the overexpression of ABC transporters such as P-glycoprotein (P-gp/MDR1/ABCB1), multidrug resistance-associated proteins (MRPs/ABCCs), and breast cancer resistance protein (BCRP/ABCG2), which limits the efficacy of chemotherapeutic drugs. The aim of this review is to compile information about transcriptional and post-transcriptional regulation of ABC transporters and discuss their role in mediating MDR in cancer cells. This review also focuses on drug resistance by ABC efflux transporters in cancer cells, particularly hepatocellular carcinoma (HCC) and colorectal carcinoma (CRC) cells. Some aspects of the chemotherapy failure and future directions to overcome this problem are also discussed.

The role of phase I and II genetic polymorphisms, smoking, alcohol and cancer family history, in the risk of developing testicular cancer

BACKGROUND

Testicular cancer (TCa) is a malignant tumor with highest incidence and mortality rates in Chile. The genes coding for cytochrome P450, glutathione-S-transferases (GSTs), and UDP glucuronyl transferases (UGT) participate in the biotransformation and detoxification of xenobiotics. Mutations in these genes have been associated with a high incidence of various types of cancer and an increased risk of presenting adverse reactions to drugs.

OBJECTIVE

The aim of this study was to relate the presence of genetic polymorphisms in cytochrome P450 1A1 (CYP1A1), CYP3A4, GSTM1, GSTP1, GSTT1, and UGT1A1 genes and nongenetic factors with the risk of developing TCa.

METHODS

A total of 276 volunteers from the Chilean general population and 251 Chilean TCa patients were recruited for the study. Genotypic analyses were performed using qPCR and PCR-RFLP.

RESULTS

Variant alleles found to increase the risk of developing TCa were CYP1A1*2C (rs1048943), GSTP1 (rs1695), and GSTT1null, especially when in conjunction with a cancer family history and/or a smoking habit. The results of the multivariate analysis showed that the presence of variant alleles of GSTP1 (rs1695) together with a smoking habit and a family history of cancer accounted for a 15.9% risk of developing TCa in the Chilean population. CYP1A1*2C, GSTM1null, GSTT1null, and GSTP1 (rs1695) are statistically related to the risk of appearance of TCa, alone or associated with nongenetic factors.

CONCLUSION

Therefore, phase I and II variant alleles might be useful in evaluating susceptibility to TCa in the studied population.

The Association of Consumption of Animal Proteins and the Risk of Esophageal Cancer

Aim: Esophageal cancer (EC) is considered one of the most common types of cancer in the world. High intake of dietary proteins is suggested to increase EC. This study examined associations between intake of red meats, processed meat, poultry, and fish and the risk of EC. Methods: This hospital-based Case-Control study included 96 people with EC and 187 people without EC from Bojnurd, Iran. Socio-demographic data was collected from all participants at enrollment using general information questionnaire. Dietary intake was assessed using a validated 168 item semi-quantitative food frequency questionnaire. Results: After adjusting for potential confounders, there was a significant association between the consumption of beef (P = 0.04), processed meats (sausages) (P = 0.01), and chicken with skin (P = 0.001) with the risk of EC. Conclusion: We observed a positive association between red meat, processed meats (sausages), chicken with skin and the risk of EC. The use of lamb meat and fish had no significant association with the risk of EC.

Empirically derived dietary patterns and ovarian cancer risk: a meta-analysis

Dietary patterns, which reflect overall diet and possible nutrient and food interactions, have been reported to be related to ovarian cancer (OC) risk. However, studies on the relationship between dietary patterns and OC risk have been inconsistent. Thus, we carried out a systematic meta-analysis to assess the relationship between dietary patterns and the risk of OC. Relevant studies are identified by searching the Medline and Embase electronic databases up to December 2016. The Cochrane Q statistic and the I statistical were used to evaluate heterogeneity. A total of 22 studies fulfilled the inclusion criteria and were included in this meta-analysis. There was evidence of a decreased risk for OC in the highest versus the lowest categories of healthy dietary pattern [odds ratio (OR)=0.86; 95% confidence interval (CI): 0.74-0.99; P=0.04]. An increased risk of OC was shown for the highest versus the lowest category of a western-style dietary pattern (OR=1.19; 95% CI: 1.01-1.41; P=0.04). No significant association with OC risk was observed in the highest versus the lowest category of a heavy drinking pattern (OR=0.89; 95% CI: 0.67-1.19; P=0.42). The results of this meta-analysis suggest that a healthy dietary pattern is associated with reduced risk for OC and a western-style dietary pattern is associated with an increased risk of OC. Further studies are needed to confirm our results.

Using Machine Learning to Predict Progression in the Gastric Precancerous Process in a Population from a Developing Country Who Underwent a Gastroscopy for Dyspeptic Symptoms

Background

Gastric cancer is the fourth most common cancer and the third most common cause of cancer deaths worldwide. Morbidity and mortality from gastric cancer may be decreased by identification of those that are at high risk for progression in the gastric precancerous process so that they can be monitored over time for early detection and implementation of preventive strategies.

Method

Using machine learning, we developed prediction models for gastric precancerous progression in a population from a developing country with a high rate of gastric cancer who underwent gastroscopies for dyspeptic symptoms. In the data imputed for completeness, we divided the data into a training and a validation test set. Using the training set, we used the random forest method to rank potential predictors based on their predictive importance. Using predictors identified by the random forest method, we conducted best subset linear regressions with the leave-one-out cross-validation approach to select predictors for overall progression and progression to dysplasia or cancer. We validated the models in the test set using leave-one-out cross-validation.

Results

We observed for all models that complete intestinal metaplasia and incomplete intestinal metaplasia were the strongest predictors for further progression in the precancerous process. We also observed that a diagnosis of no gastritis, superficial gastritis, or antral diffuse gastritis at baseline was a predictor of no progression in the gastric precancerous process. The sensitivities and specificities were 86% and 79% for the general model and 100% and 82% for the location-specific model, respectively.

Conclusion

We developed prediction models to identify gastroscopy patients that are more likely to progress in the gastric precancerous process, among whom routine follow-up gastroscopies can be targeted to prevent gastric cancer. Future external validation is needed.

Mechanistic Evidence for Red Meat and Processed Meat Intake and Cancer Risk: A Follow-up on the International Agency for Research on Cancer Evaluation of 2015

The Working Group of the International Agency for Research on Cancer classified the consumption of processed meat as carcinogenic to humans (Group 1), and classified red meat as probably carcinogenic to humans (Group 2A); consumption of both meat types is associated with an increased risk of colorectal cancer. These classifications are based on a compilation of epidemiology data and mechanistic evidence from animal and human studies. The curing of meats with nitrite can produce carcinogenic N-nitroso compounds (NOCs), and the smoking of meat produces polycyclic aromatic hydrocarbons (PAHs). The high-temperature cooking of meat also produces carcinogenic heterocyclic aromatic amines (HAAs). The ingestion of heme from meat can catalyze the formation of NOCs and lipid peroxidation products (LPOs) in the digestive tract. Many of these chemicals form DNA adducts, some of which can induce mutations and initiate carcinogenesis. Another recent hypothesis is that N-glycolylneuraminic acid, a non-human sialic acid sugar present in red meat, becomes incorporated in the cell membrane, triggering the immune response with associated inflammation and reactive oxygen species, which can contribute to DNA damage, tumor promotion, and cancer. The mechanisms by which these chemicals in meat induce DNA damage, and the impact of dietary and host factors that influence the biological potency of these chemicals are highlighted in this updated report.

Selected Psychological Aspects of Meat Consumption-A Short Review

Eating meat is deeply entrenched in Western culture. It is often associated with wealth and a highly nutritional diet; and for many people it is also an established habit that is difficult to change. The second half of the 20th century was a period of rapid growth in meat consumption, which resulted in intensified meat production. At the same time, eating meat has recently become subject to criticism for health-related, environmental or humanitarian reasons. This review aims to signal the potential consequences of a change of diet or switching to diets that are rich/poor in certain ingredients on the functioning of the hormonal and nervous system, which translates into changes in mood and behavior. This paper discusses the psychological phenomena which underlie the difficulty of changing one's food preferences and problems encountered while adding new products to the daily diet. Finally, this study summarizes the limitations of modifying eating habits that have resulted from established attitudes and habits.

Prostate Cancer Incidence is Correlated to Total Meat Intake– a Cross-National Ecologic Analysis of 172 Countries

Objective: To examine the association of total meat (animal flesh) consumption to prostate cancer incidence (PC61) at population level. Subjects and Methods: Data from 172 countries were extracted for analysis. Associations between country specific per capita total meat intake and PC61 incidence at country level were examined using Pearson’s r and Spearman rho, partial correlation, stepwise multiple linear regression analyses with ageing, GDP, Is (index of magnitude of prostate cancer gene accumulation at population level), obesity prevalence and urbanization included as the confounding factors. Countries were also grouped for regional association analysis. The data were log-transformed for analysis in SPSS. Microsoft Excel, and ANOVA Post hoc Scheffe tests were applied to calculate and compare mean differences between country groupings. Results: Worldwide, total meat intake was strongly and positively associated with PC61 incidence in Pearson’s r (r= 0.595, p<0.001) and Spearman rho (r= 0.637, p<0.001) analyses. This relationship remained significant in partial correlation (r= 0.295, p<0.001) when ageing, GDP, Is, obesity prevalence and urbanization were kept statistically constant. GDP was weakly and insignificantly associated with PC61 when total meat intake was kept statistically constant. Stepwise multiple linear regression identified that total meat was a significant predictor of PC61 with total meat intake and all the five confounders included as the independent variables (R2=0.417). Post hoc Scheffe tests revealed nine significant mean differences of PC61 between the six WHO regions, but all disappeared when the contributing effect of total meat on PC61 incidence rate was removed. GDP was not identified as the statistically significant predictor of PC61 in either of the models including or excluding total meat as the independent variable. Conclusions: Total meat intake is an independent predictor of PC61 worldwide, and the determinant of regional variation of PC61. The longitudinal cohort studies are proposed to explore the association further.

Chemical speciation, including polycyclic aromatic hydrocarbons (PAHs), and toxicity of particles emitted from meat cooking operations

We assessed the chemical properties and oxidative stress of particulate matter (PM) emissions from underfired charbroiled meat operations with and without the use of aftertreatment control technologies. Cooking emissions concentrations showed a strong dependence on the control technology utilized, with all emission rates showing decreases with the control technologies compared to the baseline testing. The organic acids profile was dominated by the saturated nonanoic, myristic, palmitic, and stearic acids, and the unsaturated oleic, elaidic, and palmitoleic acids. Cholesterol was also found in relatively high concentrations. Lower and medium-weight polycyclic aromatic hydrocarbons (PAHs) were the dominant species for all cooking experiments. Heavier PAHs were also detected in high concentrations, especially in the particle-phase. For the nitrated PAH emissions (nitro-PAHs), low molecular weight compounds dominated the cooking emissions. Under the present experimental conditions, the heterocyclic aromatic amines (HAAs) showed very low concentrations, which suggests these species are rarely formed in meat cooking PM. The most efficient control technology for reducing the majority of the toxic pollutants was the electrostatic precipitator, which resulted in total emissions reductions on the order of 95%, 79%, 90%, 96%, 90%, and 94%, respectively, for particle-phase PAHs, gas-phase PAHs, particle-phase nitro-PAHs, gas-phase nitro-PAHs, particle-phase HAAs, and gas-phase HAAs compared to the baseline testing. Our experiment showed that cooking aerosol contained higher levels of prooxidants in the particle-phase and the corresponding vapors contained higher levels of electrophiles. Overall, the use of control technologies reduced the redox and electrophilic activities of cooking PM.

Anatomical subsite can modify the association between meat and meat compounds and risk of colorectal adenocarcinoma: Findings from three large US cohorts

Distal and proximal colon tumors have distinct incidence trends and embryonic origins; whether these sub-sites have distinct susceptibilities to known risk factors is unclear. We used pooled data from 407,270 participants in three US-based studies, with overall median follow-up of 13.8 years. We used adjusted Cox models to analyze the association between dietary intakes (from diet history questionnaire) of total, processed and unprocessed red meat; total white meat, poultry and fish and meat-related compounds: heme iron, nitrate, nitrite, the heterocyclic amines (HCAs) and benzo(a)pyrene (B(a)P) and incidence of colorectal cancer subsites. The risk of colorectal cancer (n = 6,640) increased by 35% for each 50 g/1,000 kcal higher daily intake of total red meat, with a significant right-to-left trend from proximal colon (HR: 1.24; 95% CI: 1.09-1.39) to distal colon (HR: 1.34; 95% CI: 1.13-1.55) and rectum (HR: 1.53; 95% CI: 1.28-1.79). Only unprocessed red meat showed a significant right-to-left trend. Each 50 g/1,000 kcal increase in white meat intake was associated with a 26% reduction in total colorectal cancer risk (HR: 0.74; 95% CI: 0.68-0.80), with a significant inverse right-to-left trend. The highest quintile of heme iron was associated with increased cancer risk only in the distal colon (HR: 1.20; 95% CI: 1.02-1.42) and rectum (HR: 1.27; 95% CI: 1.07-1.52). The highest quintile of HCAs, and nitrate/nitrite were associated with increased risk of total colorectal cancer, but these associations did not vary across anatomical subsites. In summary, right and left subsites of the colon may have distinct susceptibilities to meat and possibly other dietary risk factors, suggesting that the causes of colorectal cancer may vary across anatomical subsites.

Role of diet and food intake in age-related macular degeneration: a systematic review

A systematic literature review was conducted to evaluate the role of diet and food intake in age-related macular degeneration (AMD). Eighteen high-quality studies were identified. Adherence to a Mediterranean diet had decreased risk of AMD progression. An Oriental diet pattern had decreased association with AMD prevalence, whereas a Western diet pattern had increased association with AMD prevalence. High consumption of vegetables rich in carotenoids and fatty fish containing omega-3 fatty acids was beneficial for those at risk of AMD. Vegetable oils and animal fats containing omega-6 fatty acids, and red/processed meat should be consumed minimally to reduce the risk of AMD progression. High glycaemic index diets and alcohol consumption of greater than two drinks a day had increased association with AMD. As the quality of diet and food intake had a vital role in AMD, the provision of appropriate nutritional advice to those at risk of AMD is recommended.