Dietary factors in human colorectal cancer

Association between adherence to a dietary approach to stop hypertension and the Mediterranean diets and risk of colorectal cancer: A matched case-control study

BACKGROUND

Colorectal cancer (CRC) is one of the most common cancers and is currently the third leading cause of cancer-related deaths worldwide. This study aimed to evaluate whether the dietary approach to stop hypertension (DASH) and Mediterranean (MED) diets are associated with CRC in Iranian adults.

METHODS

This hospital-based case-control study was conducted on 71 cases and 142 controls (40-75 years old) in three general hospitals in Tehran, Iran. The dietary intakes of individuals were collected through face-to-face interviews using a semi-quantitative food frequency questionnaire (FFQ) that included 125 food items. The DASH and MED diet scores were calculated according to food items based on guidelines. Two logistic regression models were applied to evaluate the association between DASH and MED score adherence.

RESULTS

After adjusting for confounding factors, a negative association between DASH diet adherence and CRC risk was observed in the second and last tertile compared to the first tertile (T) (T2: odds ratio (OR) = 0.33; 95% confidence interval (CI): 0.14-0.77 - T3: OR = 0.09; 95% CI: 0.03-0.27). There was no significant association between the MED diet and the risk of CRC.

CONCLUSIONS

In conclusion, the current study's findings presented that adherence to a DASH diet could reduce the odds of CRC.

Targeting colorectal cancer using dietary flavonols

Colorectal cancer is among the well-known forms of cancer and a prominent cause of cancer demises worldwide. In vitro experiments reinforced by animal studies, as well as epidemiological studies of human colorectal cancer propose that the growth of this disease can be moderated by eating aspects. Dietary intake including green vegetables and fruits may result in the reduction of colon cancer chances. The finding suggests that the combinations of dietary nutrients may deliver additive or synergistic effects and might be a powerful method to avoid or eradicate colon cancer beginning and/or development. Flavonols are one of the most widespread dietary nutrients of the polyphenols-flavonoids and major constituent of Allium and Brassicaceae vegetables. Flavonols present in vegetables of Allium and Brassicaceae family are kaempferol, myricetin, quercetin, and isorhamnetin. These flavonols are claimed to have antiproliferative activity in vivo and in vitro against colorectal cancer. The objective of this review is to summarize the role of flavonols obtained from dietary sources in the prevention and treatment of colorectal cancer.

Potential impact of time trend of whole grain intake on burden of major cancers in China

Numerous studies have revealed associations between high intake of whole grains and reduced risk of various cancers. Yet, in recent decades, the traditional Chinese diets have been challenged by reduction in whole grains and increase in refined grains. To assess the impact of this dietary transition on cancer prevention, we analyzed the time trend of whole grain intake using nationally representative sampling data of over 15 thousand individuals from the China Health and Nutrition Survey. We applied the comparative risk assessment method to estimate the population attributable fraction of cancers due to insufficient whole grain intake from 1997 to 2011 and projected the trend of whole grain intake and the associated burden of cancers to 2035. We found a significant decrease of approximately 59% of whole grain intake in the Chinese population from 1997 to 2011. Compared with 1997, insufficient intake of whole grains was responsible for 9940 more cases of breast cancer, 12,903 more cases of colorectal cancer and 434 more cases of pancreatic cancer in 2011. Our projections suggest that if every Chinese would consume 125 g whole grain per day as recommended by the latest Chinese Dietary Guidelines, 0.63% bladder cancer, 8.98% breast cancer, 15.85% colorectal cancer, 3.86% esophageal cancer, 2.52% liver cancer and 2.22% pancreatic cancer (totaling 186,659 incident cases) could theoretically be averted by 2035. Even if everyone maintained the 2011 whole grain intake level, an estimated 8.38% of cancer events could still be prevented by 2035.

Effects of Food Factors and Processing on Protein Digestibility and Gut Microbiota

Protein is an essential macronutrient. The nutritional needs of dietary proteins are met by digestion and absorption in the small intestine. Indigestible proteins are further metabolized in the gut and produce metabolites via protein fermentation. Thus, protein indigestibility exerts a wide range of effects on gut microbiota composition and function. This review aims to discuss protein digestibility, the effects of food factors, such as protein sources, intake level, and amino acid composition, and making meat analogues. Besides, it provides an inventory of antinutritional factors and processing techniques that influence protein digestibility and, consequently, the diversity and composition of intestinal microbiota. Future studies are warranted to understand the implication of plant-based analogues on protein digestibility and gut microbiota and to elucidate the mechanisms concerning protein digestibility to host gut microbiota using various omics techniques.

Beneficial insights into postbiotics against colorectal cancer

Colorectal cancer (CRC) is one of the most prevalent and life-threatening cancer types with limited therapeutic options worldwide. Gut microbiota has been recognized as the pivotal determinant in maintaining gastrointestinal (GI) tract homeostasis, while dysbiosis of gut microbiota contributes to CRC development. Recently, the beneficial role of postbiotics, a new concept in describing microorganism derived substances, in CRC has been uncovered by various studies. However, a comprehensive characterization of the molecular identity, mechanism of action, or routes of administration of postbiotics, particularly their role in CRC, is still lacking. In this review, we outline the current state of research toward the beneficial effects of gut microbiota derived postbiotics against CRC, which will represent the key elements of future precision-medicine approaches in the development of novel therapeutic strategies targeting gut microbiota to improve treatment outcomes in CRC.

The global disease burden attributable to a diet low in fibre in 204 countries and territories from 1990 to 2019

OBJECTIVE

The relationship of a diet low in fibre with mortality has not been evaluated. This study aims to assess the burden of non-communicable chronic diseases (NCD) attributable to a diet low in fibre globally from 1990 to 2019.

DESIGN

All data were from the Global Burden of Disease (GBD) Study 2019, in which the mortality, disability-adjusted life-years (DALY) and years lived with disability (YLD) were estimated with Bayesian geospatial regression using data at global, regional and country level acquired from an extensively systematic review.

SETTING

All data sourced from the GBD Study 2019.

PARTICIPANTS

All age groups for both sexes.

RESULTS

The age-standardised mortality rates (ASMR) declined in most GBD regions; however, in Southern sub-Saharan Africa, the ASMR increased from 4·07 (95 % uncertainty interval (UI) (2·08, 6·34)) to 4·60 (95 % UI (2·59, 6·90)), and in Central sub-Saharan Africa, the ASMR increased from 7·46 (95 % UI (3·64, 11·90)) to 9·34 (95 % UI (4·69, 15·25)). Uptrends were observed in the age-standardised YLD rates attributable to a diet low in fibre in a number of GBD regions. The burden caused by diabetes mellitus increased in Central Asia, Southern sub-Saharan Africa and Eastern Europe.

CONCLUSIONS

The burdens of disease attributable to a diet low in fibre in Southern sub-Saharan Africa and Central sub-Saharan Africa and the age-standardised YLD rates in a number of GBD regions increased from 1990 to 2019. Therefore, greater efforts are needed to reduce the disease burden caused by a diet low in fibre.

Factors Associated with Colorectal Cancer Prevalence Among Long-Haul Truck Drivers in the United States

PURPOSE

To determine the age-adjusted association between colorectal cancer (CRC) risk factors and CRC prevalence among long-haul truck drivers (aged 21-85), after adjustment for age.

DESIGN

Pooled cross-sectional analysis using Commercial Driver Medical Exam (CDME) data. Setting. National survey data from January 1, 2005, to October 31, 2012.

PARTICIPANTS

47,786 commercial motor vehicle drivers in 48 states.

MEASURES

CRC prevalence was the primary outcome; independent variables included demographics, body mass index (BMI), and concomitant medical conditions.

ANALYSIS

Kruskal-Wallis tests to analyze continuous variables; Fischer's exact tests to analyze categorical variables; univariate and multivariable logistic regression for rare events (Firth method) to quantify the association between the independent variables of interest and CRC prevalence. Odds ratios (ORs) and 95% confidence intervals (CIs) were adjusted for age, gender, years with current employer, year of exam, and BMI in a multivariate logistic regression.

RESULTS

Many factors were statistically significant. Obesity (OR = 3.14; 95% CI = 1.03-9.61) and increasing age (OR = 1.10 per year; 95% CI = 1.07-1.13) were significantly associated with CRC prevalence. Truckers with 4 or more concomitant medical conditions were significantly more likely to have CRC (OR = 7.03; 95% CI = 1.83-27.03).

CONCLUSIONS

Our findings highlight mutable risk factors and represent an opportunity for intervention that may decrease CRC morbidity and mortality among truck drivers, a unique population in the United States estimated to live up to 16 years less than the general population.

Associations of Evolutionary-Concordance Diet and Lifestyle Pattern Scores with Incident, Sporadic Colorectal Adenoma in a Pooled Case-Control Study

Differences in diet and lifestyle relative to those of our Paleolithic-era ancestors may explain current high incidences of chronic diseases, including colorectal cancer (CRC), in Westernized countries. Previously reported evolutionary-concordance diet and lifestyle pattern scores, reflecting closeness of diet and lifestyle patterns to those of Paleolithic-era humans, were associated with lower CRC incidence. Separate and joint associations of the scores with colorectal adenoma among men and women are unknown. To address this, we pooled data from three case-control studies of incident, sporadic colorectal adenomas (n = 771 cases, 1,990 controls), used participants' responses to food frequency and lifestyle questionnaires to calculate evolutionary-concordance diet and lifestyle pattern scores, and estimated the scores' associations with adenomas using multivariable unconditional logistic regression. The multivariable-adjusted odds ratios comparing those in the highest relative to the lowest diet and lifestyle score quintiles were 0.84 (95% confidence interval [CI] 0.62, 1.12; P_trend:0.03) and 0.41 (95% CI 0.29, 0.59; P_trend:<0.0001), respectively. The inverse associations were stronger for high-risk adenomas, and among those with both high relative to those with both low diet and lifestyle scores. These results suggest that more evolutionary-concordant diet and lifestyle patterns, separately and jointly, may be associated with lower risk for incident, sporadic colorectal adenoma.Supplemental data for this article is available online at https://doi.org/10.1080/01635581.2021.2002919 .

Phenolic content, antioxidant, cytotoxic and antiproliferative effects of fractions of Vigna subterraenea (L.) verdc from Mpumalanga, South Africa

Consistent intake of legumes has been correlated with decreased possibility of developing colorectal cancer (CRC) due to the content of some phytochemicals like polyphenols. Bambara groundnut (BGN) is an underutilized crop with a rich nutritional profile, but have not been exploited for its nutraceutical and medicinal benefits. In this study, total polyphenol, flavonoid (flavonol and flavanol) content, antioxidant activity and cytotoxicity/antiproliferative properties of 70% ethanolic extracts of whole BGN, cotyledon and seed coat on Caco-2 and HT-29 colon cancer cells were evaluated. Seed coat had a significantly (p < 0.05) higher composition of total polyphenol, flavonol and flavan-3-ol (flavanol) compared to whole seed and cotyledon. Antioxidant activity determined with ferric reducing antioxidant power (FRAP), 2,2- azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and oxygen radical absorbance capacity (ORAC) assays, showed that seed coat with higher polyphenolic content had significantly (p < 0.05) greater antioxidant activity. BGN fractions demonstrated cytotoxic and antiproliferative effects against HT-29 and Caco-2 colon cancer cells in a dose-dependent manner, with seed coat and whole seed exhibiting greater cytotoxicity and higher antiproliferative activity and colon cancer cell inhibition. Extracts of the cotyledon also showed cytotoxic activity and hindered cancer cell growth/division but to a significantly (p < 0.05) lower magnitude. BGN parts indicated a greater cytotoxic effect and potential to slow down Caco-2 colon cancer cell growth and division over HT-29. This result provides new knowledge on the possible health benefits of BGN, as well as the potential for product development and may influence its consumption and utilisation.

Higher intake of whole grains and dietary fiber are associated with lower risk of liver cancer and chronic liver disease mortality

The relationship between dietary factors and liver disease remains poorly understood. This study evaluated the associations of whole grain and dietary fiber intake with liver cancer risk and chronic liver disease mortality. The National Institutes of Health–American Association of Retired Persons Diet and Health Study cohort recruited 485, 717 retired U.S. participants in 1995–1996. Follow-up through 2011 identified 940 incident liver cancer cases and 993 deaths from chronic liver disease. Compared with the lowest, the highest quintile of whole grain intake was associated with lower liver cancer risk (Hazard ratio [HR]_{Q5 vs. Q1} = 0.78, 95% confidence interval [CI]: 0.63–0.96) and chronic liver disease mortality (HR_{Q5 vs. Q1} = 0.44, 95% CI: 0.35–0.55) in multivariable Cox models. Dietary fiber was also associated with lower liver cancer risk (HR_{Q5 vs. Q1} = 0.69, 95% CI: 0.53–0.90) and chronic liver disease mortality (HR_{Q5 vs. Q1} = 0.37, 95% CI: 0.29–0.48). Fiber from vegetables, beans and grains showed potential protective effect. Here, we show that higher intake of whole grain and dietary fiber are associated with lower risk of liver cancer and liver disease mortality.

Higher intake of dietary fiber and whole grains are associated with reduced risk of various diseases including some cancers. Here, the authors estimate reductions in liver cancer of 22% and 31% and chronic liver disease mortality of 56% and 63% associated with increased whole grain and dietary fiber intake, respectively.

Citrus Genus and Its Waste Utilization: A Review on Health-Promoting Activities and Industrial Application

Citrus fruits such as oranges, grapefruits, lemons, limes, tangerines, and mandarins, whose production is increasing every year with the rise of consumer demand, are among the most popular fruits cultivated throughout the globe. Citrus genus belongs to the Rutaceae family and is known for its beneficial effects on health for centuries. These plant groups contain many beneficial nutrients and bioactive compounds. These compounds have antimicrobial, anticancer, antidiabetic, antiplatelet aggregation, and anti-inflammatory activities. Citrus waste, generated by citrus-processing industries in large amounts every year, has an important economic value due to richness of bioactive compounds. The present review paper has summarized the application and properties of Citrus and its waste in some fields such as food and drinks, traditional medicine practices, and recent advances in modern approaches towards pharmaceutical and nutraceutical formulations.

Sweet Potato Leaf Feeding Decreases Cholesterol, Oxidative Stress and Thrombosis Formation in Syrian Hamsters with a High-Cholesterol Diet

Nutritional strategies to reduce hyperlipidemia and the risk of cardiovascular disease are gaining more public favor and medical professionals’ attention. The authors of this study explored the effect of sweet potato leaf powder (SPLP) feeding on the parameters of plasma lipids, reactive oxygen species, and time to thrombosis formation in Syrian hamsters fed with high-cholesterol diets. The animals were separated into six groups: a feeding control diet, a control diet containing 0.1% cholesterol, a control diet containing 0.2% cholesterol, a control diet containing 0.1% cholesterol plus 2.5% SPLP, a control diet containing 0.1% cholesterol plus 5% SPLP, and a control diet containing 0.2% cholesterol plus 5% SPLP for six weeks. The levels of serum total cholesterol (51% increase), low-density lipoprotein cholesterol (70.6% increase), very-low-density lipoprotein cholesterol (51.3% increase), and the triglyceride and atherogenic index (LDL-C/HDL-C) significantly increased in the high-cholesterol diet groups. Concomitant 5% sweet potato leaf powder ingestion significantly decreased the lipid profiles, with a 20.6% total cholesterol reduction in the 0.1% cholesterol diet groups, a 17.2% reduction in the 0.2% group, a 48.7% LDL reduction in the 0.1% cholesterol group, and a 30.3% reduction in the 0.2% group, with a consequent decrease in the atherogenic index. SPLP feeding was found to be associated with increased fecal sterol contents, with a 188.6% increase in the 0.1% cholesterol-fed group and a 177.3% increase in the 0.2% group. The SPLP-fed groups had depressed ROS levels, elongated FeCl₃-induced times to thrombosis formation, and increased liver superoxide dismutase contents and SREBP-1 protein expression. Sweet potato leaf intake could reduce plasma total cholesterol, LDL, and oxidative stress. We suggest sweet potato leaf intake as a choice of nutritional strategy for hyperlipidemia and cardiovascular disease prevention.

The effect of vitamin D on the occurrence and development of colorectal cancer: a systematic review and meta-analysis

PURPOSE

There has been a lot of controversies about the correlation between vitamin D and colorectal cancer (CRC). In this meta-analysis, we purposed to explore the relationship between vitamin D and the incidence of CRC/the prognosis of CRC.

METHODS

A systematic search for articles in databases (Pubmed, Web of Science, EBSCO and Cochrane Library) was terminated in April 2020. The primary outcomes were the incidence rate of CRC and the long-term survival of patients with CRC.

RESULTS

According to the estimated pooled OR from 21 eligible studies, covering 904,152 people, the use of vitamin D was inversely associated with the incidence of CRC [OR = 0.87, (0.82-0.92)]. Among the four studies included in this meta-analysis, covering 7486 patients, compared the overall survival (OS) of CRC between the vitamin D users and the non-users. Based on the estimated pooled HR, vitamin D potentially improved the long-term survival of CRC patients [HR = 0.91, (0.83-0.98)].

CONCLUSION

This meta-analysis demonstrates that vitamin D not only has a positive impact on the incidence of CRC from either the dietary or supplemental sources but also benefits clinical outcomes and improves the long-term survival of CRC patients. However, further studies are recommended to clarify the above phenomena.

Suppression of Membranous LRP5 Recycling, Wnt/β-Catenin Signaling, and Colon Carcinogenesis by 15-LOX-1 Peroxidation of Linoleic Acid in PI3P

APC mutation activation of Wnt/β-catenin drives initiation of colorectal carcinogenesis (CRC). Additional factors potentiate β-catenin activation to promote CRC. Western diets are enriched in linoleic acid (LA); LA-enriched diets promote chemically induced CRC in rodents. 15-Lipoxygenase-1 (15-LOX-1), the main LA-metabolizing enzyme, is transcriptionally silenced during CRC. Whether LA and 15-LOX-1 affect Wnt/β-catenin signaling is unclear. We report that high dietary LA promotes CRC in mice treated with azoxymethane or with an intestinally targeted Apc mutation (Apc^Δ580) by upregulating Wnt receptor LRP5 protein expression and β-catenin activation. 15-LOX-1 transgenic expression in mouse intestinal epithelial cells suppresses LRP5 protein expression, β-catenin activation, and CRC. 15-LOX-1 peroxidation of LA in phosphatidylinositol-3-phosphates (PI3P_LA) leads to PI3P_13-HODE formation, which decreases PI3P binding to SNX17 and LRP5 and inhibits LRP5 recycling from endosomes to the plasma membrane, thereby increasing LRP5 lysosomal degradation. This regulatory mechanism of LRP5/Wnt/β-catenin signaling could be therapeutically targeted to suppress CRC.

Burden and trend of ischemic heart disease and colorectal cancer attributable to a diet low in fiber in China, 1990-2017: findings from the Global Burden of Disease Study 2017

PURPOSE

The burden of non-communicable diseases (NCDs) has increased in China. However, the contribution of dietary risks to the NCD burden has not been evaluated. This study aimed to estimate the burden of ischemic heart disease (IHD) and colorectal cancer (CRC) attributable to a diet low in fiber in China from 1990 to 2017.

METHODS

China data from the Global Burden of Disease Study (GBD) 2017 were used to assess the age-, sex-, and province-specific mortality and disability-adjusted life-years (DALYs) of IHD and CRC related to a diet low in fiber.

RESULTS

In 2017, a diet low in fiber contributed 170,143 [95% uncertainty interval (UI): 99,623-256,806] IHD deaths and 25,561 (95% UI: 13,726-39,215) CRC deaths, with the population attributable fractions (PAFs) were 9.7 and 13.7%, respectively. Males had higher risk-attributable mortality and DALY rates for IHD and CRC than females. An upward trend with age in rates of mortality and DALY was observed. All-age risk-attributable mortality and DALY rates increased significantly by 111.4 and 53.2% for IHD, and 94.4 and 59.6% for CRC from 1990 to 2017, respectively; however, the corresponding age-standardized rates for IHD and CRC showed relatively stable trends. Heilongjiang, Xinjiang, and Inner Mongolia were ranked as the top three provinces in terms of total risk-attributable NCD burden in 2017.

CONCLUSIONS

China has a large and growing NCD burden attributable to a diet low in fiber. Greater priority in disease prevention and control should be given to male and older adults throughout China, particularly in some western provinces.

Melissa officinalis Extract Induces Apoptosis and Inhibits Migration in Human Colorectal Cancer Cells

Colorectal cancer (CRC) is one of the most frequently diagnosed cancers worldwide. Lifestyle-related factors, such as diet, are associated with the development of CRC. Cumulating evidence indicates noticeable chemopreventive effects of phytochemicals on CRC, suggesting that drinking herbal tea potentially reduces the risk of distal colon cancer via its antiproliferative and anti-angiogenic activities. We examine the antitumor effects of nine components frequently found in herbal tea and uncover the underlying molecular mechanism. Among them, the hot water extract of Melissa officinalis (MO) exhibited the highest anticancer activity on CRC cells. We revealed that MO reduced cell proliferation, induced cell cycle arrest at the G₂/M phase, triggered caspase-dependent apoptotic cell death, and inhibited cell migration ability by modulating the epithelial-mesenchymal transition in HCT116 CRC cells. To examine the metabolite composition in the MO hot water extract, we applied mass spectrometry-based analysis and identified 67 compounds. Among them, the phenolic compounds, including lignans, phenylpropanoids, and polyketides, are widely found in natural products and possess various bioactivities such as anti-inflammatory, antioxidation, and anticancer effects. The results indicate that herbal tea consumption benefits CRC prevention and management.

Whole grain and dietary fiber intake and risk of colorectal cancer in the NIH-AARP Diet and Health Study cohort

BACKGROUND

Whole grains and other foods containing fiber are thought to be inversely related to colorectal cancer (CRC). However, whether these associations reflect fiber or fiber source remains unclear.

OBJECTIVES

We evaluated associations of whole grain and dietary fiber intake with CRC risk in the large NIH-AARP Diet and Health Study.

METHODS

We used Cox proportional hazard models to estimate HRs and 95% CIs for whole grain and dietary fiber intake and risk of CRC among 478,994 US adults, aged 50-71 y. Diet was assessed using a self-administered FFQ at baseline in 1995-1996, and 10,200 incident CRC cases occurred over 16 y and 6,464,527 person-years of follow-up. We used 24-h dietary recall data, collected on a subset of participants, to evaluate the impact of measurement error on risk estimates.

RESULTS

After multivariable adjustment for potential confounders, including folate, we observed an inverse association for intake of whole grains (HRQ5 vs.Q1 : 0.84; 95% CI: 0.79, 0.90; P-trend < 0.001), but not dietary fiber (HRQ5 vs. Q1: 0.96; 95% CI: 0.88, 1.04; P-trend = 0.40), with CRC incidence. Intake of whole grains was inversely associated with all CRC cancer subsites, particularly rectal cancer (HRQ5 vs. Q1: 0.76; 95% CI: 0.67, 0.87; P-trend < 0.001). Fiber from grains, but not other sources, was associated with lower incidence of CRC (HRQ5 vs. Q1: 0.89; 95% CI: 0.83, 0.96; P-trend < 0.001), particularly distal colon (HRQ5 vs. Q1: 0.84; 95% CI: 0.73, 0.96; P-trend = 0.005) and rectal cancer (HRQ5 vs. Q1: 0.77; 95% CI: 0.66, 0.88; P-trend < 0.001).

CONCLUSIONS

Dietary guidance for CRC prevention should focus on intake of whole grains as a source of fiber.

Associations between consumption of dietary fibers and the risk of cardiovascular diseases, cancers, type 2 diabetes, and mortality in the prospective NutriNet-Santé cohort

BACKGROUND

Mounting evidence, yet with varying levels of proof, suggests that dietary fibers (DFs) may exert a protective role against various chronic diseases, but this might depend on the DF type and source.

OBJECTIVES

Our objectives were to assess the associations between the intake of DFs of different types [total (TDF), soluble (SF), insoluble (IF)] and from different sources (fruits, vegetables, whole grains, legumes, potatoes and tubers) and the risk of cardiovascular diseases (CVDs), cancer, type 2 diabetes (T2D), and mortality in the large-scale NutriNet-Santé prospective cohort (2009-2019).

METHODS

Overall, 107,377 participants were included. Usual DF intake was estimated from validated repeated 24-h dietary records over the first 2 y following inclusion in the cohort. Associations between sex-specific quintiles of DF intake and the risk of chronic diseases and mortality were assessed using multiadjusted Cox proportional hazards models.

RESULTS

T2D risk was inversely associated with TDFs [HR for quintile 5 compared with quintile 1: 0.59 (95% CI: 0.42, 0.82), P-trend <0.001], SFs [HR: 0.77 (0.56, 1.08); P-trend = 0.02], and IFs [HR: 0.69 (0.50, 0.96); P-trend = 0.004]. SFs were associated with a decreased risk of CVD [HR: 0.80 (0.66, 0.98); P-trend = 0.01] and colorectal cancer [HR: 0.41 (0.21, 0.79); P-trend = 0.01]. IFs were inversely associated with mortality from cancer or CVDs [HR: 0.65 (0.45, 0.94); P-trend = 0.02]. TDF intake was associated with a decreased risk of breast cancer [HR:: 0.79 (0.54, 1.13); P-trend = 0.04]. DF intake from fruit was associated with the risk of several chronic diseases.

CONCLUSIONS

Our results suggest that DF intake, especially SFs and DFs from fruits, was inversely associated with the risk of several chronic diseases and with mortality. Further studies are needed, involving different types and sources of fiber. Meanwhile, more emphasis should be put on DFs in public health nutrition policies, as DF intake remains below the recommended levels in many countries. This trial was registered at clinicaltrials.gov as NCT03335644.

Cancer Incidence and Trends

The incidence of many types of cancer continues to increase, and despite many successes in the realms of screening, prevention, and treatment, cancer remains the second leading cause of death in North America. Cancer types affecting this population have varied over time, with a trend toward more malignancies caused by modifiable risk factors related to a western lifestyle. Despite the increasing incidence of cancer, a combination of population-based screening and improved therapeutics has made the disease more survivable, and created an ever-increasing community of cancer survivors. These cancer survivors face unique challenges and require ongoing care.

A Reasonable Diet Promotes Balance of Intestinal Microbiota: Prevention of Precolorectal Cancer

Colorectal cancer (CRC) is a multifactorial disease and the second leading cause of cancer death worldwide. The pathogenesis of colorectal cancer includes genetics, age, chronic inflammation, and lifestyle. Increasing attention has recently been paid to dietary factors. Evidence from epidemiological studies and clinical research suggests that high-fibre diets can significantly reduce the incidence of CRC, whilst the consumption of high-fat diets, high-protein diets, red meat, and processed meat is high-risk factors for tumorigenesis. Fibre is a regulator of intestinal microflora and metabolism and is thus a key dietary component for maintaining intestinal health. Intestinal microbes are closely linked to CRC, with the growth of certain microbiota (such as Fusobacterium nucleatum, Escherichia coli, or Bacteroides fragilis) favouring carcinogenesis, whilst the dominant microbiota population of the intestine, such as Bacteroidetes, Firmicutes, Actinobacteria, and Proteobacteria, have multiple mechanisms of antitumour activity. Various dietary components have direct effects on the types of intestinal microflora: in the Western diet mode (high-fat, high-protein, and red meat), the proportion of conditional pathogens in the intestinal flora increases, the proportion of commensal bacteria decreases, and the occurrence of colorectal cancer is promoted. Conversely, a high-fibre diet can increase the abundance of Firmicutes and reduce the abundance of Bacteroides and consequently increase the concentration of short-chain fatty acids (SCFAs) in the intestine, inhibiting the development of CRC. This article reviews the study of the relationship between diet, intestinal microbes, and the promotion or inhibition of CRC and analyses the relevant molecular mechanisms to provide ideas for the prevention and treatment of CRC.

Different dietary fibre sources and risks of colorectal cancer and adenoma: a dose-response meta-analysis of prospective studies

Dietary fibre is believed to provide important health benefits including protection from colorectal cancer. However, the evidence on the relationships with different dietary fibre sources is mixed and little is known about which fibre source provides the greatest benefits. We conducted a dose-response meta-analysis of prospective cohorts to summarise the relationships of different fibre sources with colorectal cancer and adenoma risks. Analyses were restricted to publications that reported all fibre sources (cereals, vegetables, fruits, legumes) to increase comparability between results. PubMed and Embase were searched through August 2018 to identify relevant studies. The summary relative risks (RR) and 95 % CI were estimated using a random-effects model. This analysis included a total of ten prospective studies. The summary RR of colorectal cancer associated with each 10 g/d increase in fibre intake were 0·91 (95 % CI 0·82, 1·00; I2 = 0 %) for cereal fibre, 0·95 (95 % CI 0·87, 1·03, I2 = 0 %) for vegetable fibre, 0·91 (95 % CI 0·78, 1·06, I2 = 43 %) for fruit fibre and 0·84 (95 % CI 0·63, 1·13, I2 = 45 %) for legume fibre. For cereal fibre, the association with colorectal cancer risk remained statistically significant after adjustment for folate intake (RR 0·89, 95 % CI 0·80, 0·99, I2 = 2 %). For vegetable and fruit fibres, the dose-response curve suggested evidence of non-linearity. All fibre sources were inversely associated with incident adenoma (per 10 g/d increase: RR 0·81 (95 % CI 0·54, 1·21) cereals, 0·84 (95 % CI 0·71, 0·98) for vegetables, 0·78 (95 % CI 0·65, 0·93) for fruits) but not associated with recurrent adenoma. Our data suggest that, although all fibre sources may provide some benefits, the evidence for colorectal cancer prevention is strongest for fibre from cereals/grains.

Dietary fibre intake and the risk of diverticular disease: a systematic review and meta-analysis of prospective studies

Background

A high intake of dietary fibre has been associated with a reduced risk of diverticular disease in several studies; however, the dose–response relationship between fibre intake and diverticular disease risk has varied, and the available studies have not been summarised in a meta-analysis. We conducted a systematic review and meta-analysis of prospective cohort studies to clarify the association between dietary fibre intake, fibre subtypes, and the risk of diverticular disease.

Methods

PubMed and Embase databases were searched up to August 9th 2018. Summary relative risks (RRs) and 95% confidence intervals (CIs) were calculated using a random-effects model and nonlinear associations were modelled using fractional polynomial models.

Results

Five prospective cohort studies with 19,282 cases and 865,829 participants were included in the analysis of dietary fibre and diverticular disease risk. The summary RR was 0.74 (95% CI 0.71–0.78, I² = 0%) per 10 g/day. There was no evidence of a nonlinear association between dietary fibre intake and diverticular disease risk, p_nonlinearity = 0.35, and there was a 23%, 41% and 58% reduction in risk for an intake of 20, 30, and 40 g/day, respectively, compared to 7.5 g/day. There was no evidence of publication bias with Egger’s test, p = 0.58 and the association persisted in subgroup and sensitivity analyses. The summary RR per 10 g/day was 0.74 (95% CI 0.67–0.81, I² = 60%, n = 4) for cereal fibre, 0.56 (95% CI 0.37–0.84, I² = 73%, n = 2) for fruit fibre, and 0.80 (95% CI 0.45–1.44, I² = 87%, n = 2) for vegetable fibre.

Conclusions

These results suggest that a high fibre intake may reduce the risk of diverticular disease and individuals consuming 30 g of fibre per day have a 41% reduction in risk compared to persons with a low fibre intake. Further studies are needed on fibre types and risk of diverticular disease and diverticulitis.

Electronic supplementary material

The online version of this article (10.1007/s00394-019-01967-w) contains supplementary material, which is available to authorized users.

Review article: dietary fibre in the era of microbiome science

BACKGROUND

Explanations for the health benefits of dietary fibre have, in the past, been inconsistent and studies of the physiological effects of dietary fibre were, perhaps, directed at the wrong read-outs. Confounding factors included a failure to appreciate the molecular diversity and varied properties of fibre-types and the role of fibre as a substrate for microbial metabolism in the gut.

AIM

To present a modern perspective on fibre science and to encourage clinicians to re-consider the health impact of dietary fibre and how best to approach adjustments in dietary consumption.

METHODS

This perspective is drawn selectively from recent microbiome science; no attempt was made to perform an exhaustive review of all articles related to every aspect of dietary fibre.

RESULTS

Advances in microbiome science have revealed not only the functional impact of dietary fibre on the composition and function of the microbiota but have also demonstrated the physiologic responses to microbial-derived metabolites from fibre digestion. Moreover, studies have shown the personalised nature of host responses to dietary fibre intervention, with outcomes being dependent on individual pre-treatment gut ecology.

CONCLUSIONS

The physical properties of dietary fibres are important for homeostasis within the gut, but the predominant health benefits extend beyond the gut to enhanced metabolic welfare, including protection against obesity and related metabolic diseases. Fibre is a form of functional food joining a growing list of examples of diet-microbe-host interactions which link microbe-host metabolic and immune cascades.

Cruciferous vegetable intake and colorectal cancer risk: Japan public health center-based prospective study

We aimed to assess the association between cruciferous vegetable intake and colorectal cancer (CRC) development among Japanese adults aged between 45 and 74 years in the Japan Public Health Center-based Prospective Study. During 1 325 853 person-years of follow-up, 2612 CRC cases were identified. The association of cruciferous vegetable intake with CRC risk was assessed using a Cox proportional hazard regression model to compute hazard ratios (HRs) and 95% confidence intervals (CIs), adjusted for potential confounders. No significant association was observed between the highest cruciferous vegetable intake quartile (compared with the lowest) and CRC risk in men (multivariate HRs: 1.08; 95% CI: 0.91, 1.29) and women (multivariate HRs: 0.99; 95% CI: 0.80, 1.22) and its subsites. Women showed a marginal negative association between cruciferous vegetable intake and the risk of colon cancer (CC) after excluding participants who developed CC in the first 3 years of follow-up (P for trend = 0.08); a positive association was found with proximal CC in men. Cruciferous vegetable intake does not have a significant association with CRC risk in the Japanese general population.

Monoclonal Antibodies for the Detection of a Specific Cyclic DNA Adduct Derived from ω-6 Polyunsaturated Fatty Acids

Lipid peroxidation of polyunsaturated fatty acids (PUFAs) is an endogenous source of α,β-unsaturated aldehydes that react with DNA producing a variety of cyclic adducts. The mutagenic cyclic adducts, specifically those derived from oxidation of ω-6 PUFAs, may contribute to the cancer promoting activities associated with ω-6 PUFAs. ( E)-4-Hydroxy-2-nonenal (HNE) is a unique product of ω-6 PUFAs oxidation. HNE reacts with deoxyguanosine (dG) yielding mutagenic 1, N²-propanodeoxyguanosine adducts (HNE-dG). Earlier studies showed HNE can also be oxidized to its epoxide (EH), and EH can react with deoxyadenosine (dA) forming the well-studied εdA and the substituted etheno adducts. Using a liquid chromatography-based tandem mass spectroscopic (LC-MS/MS) method, we previously reported the detection of EH-derived 7-(1',2'-dihydroxyheptyl)-1, N⁶-ethenodeoxyadenosine (DHHεdA) as a novel endogenous background adduct in DNA from rodent and human tissues. The formation, repair, and mutagenicity of DHHεdA and its biological consequences in cells have not been investigated. To understand the roles of DHHεdA in carcinogenesis, it is important to develop an immuno-based assay to detect DHHεdA in cells and tissues. In this study we describe the development of monoclonal antibodies specifically against DHHεdA and its application to detect DHHεdA in human cells.

Risk of Colorectal Polyps and Malignancies Among Predominantly Rural Hispanics

Colorectal cancer is the fourth most frequently diagnosed cancer. However, due to variations in diet, it was hypothesized that risk of adenomatous or hyperplastic polyps or malignancies would be lower among Hispanics. Participants (n = 1671) underwent a colonoscopy. Results were grouped into one of four groups: normal, hyperplastic polyps only, adenomatous polyps, and malignancies. As expected, Hispanics had a lower risk of hyperplastic (p = .031, OR = 0.47) and adenomatous polyps (p = .031, OR = 0.66) than non-Hispanic Whites. Comparison between malignancies was not possible as no Hispanics had a malignancy. Contrary to expectations, risk of hyperplastic and adenomatous polyps and malignancies were no different between non-Hispanic Blacks and Whites. Among rural and mostly rural populations, Hispanics had a lower risk of hyperplastic and adenomatous polyps.

The Mediterranean diet and risk of colorectal cancer in the UK Women's Cohort Study

Background

Evidence from epidemiological studies investigating associations between adherence to the Mediterranean diet and colorectal cancer is inconsistent. The aim of this study is to assess in the UK Women's Cohort Study whether adherence to the Mediterranean dietary pattern is associated with reduced incidence of cancers of the colon and rectum.

Method

A total of 35 372 women were followed for a median of 17.4 years. A 10-component score indicating adherence to the Mediterranean diet was generated for each cohort participant, using a 217-item food frequency questionnaire. The Mediterranean diet score ranged from 0 for minimal adherence to 10 for maximal adherence. Cox proportional hazards regression was used to provide adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for colon and rectal cancer risk.

Results

A total of 465 incident colorectal cancer cases were documented. In the multivariable adjusted model, the test for trend was positive (HR = 0.88, 95% CI: 0.78 to 0.99; Ptrend = 0.03) for a 2-point increment in the Mediterranean diet score. For rectal cancer, a 2-point increment in the Mediterranean diet score resulted in an HR (95% CI) of 0.69 (0.56 to 0.86), whereas a 62% linear reduced risk (HR 0.38; 95% CI: 0.20 to 0.74; Ptrend < 0.001) was observed for women within the highest vs the lowest category of the MD score. Estimates for an association with colon cancer were weak (Ptrend = 0.41).

Conclusions

Findings suggest that women adhering to a Mediterranean dietary pattern may have a lower risk of colorectal cancer, especially rectal cancer.

Is dietary fibre truly protective against colon cancer? A systematic review and meta-analysis

Colorectal cancer is the third most common cancer worldwide. Growing evidence shows that about 47% of cases of colorectal cancer can be prevented by a healthy lifestyle. We performed a systematic review and meta-analysis aimed to evaluate the association between dietary fibre intake and the risk of colon cancer. We performed a structured computer search on PubMed, including epidemiological studies reporting results of dietary fibre intake and risk of colon cancer in women or men. We compared subjects exposed to the highest versus the lowest consumption. The search strategy identified 376 papers. After screening, 25 datasets were included in our meta-analysis. Results suggest a protective role of dietary fibre intake on colon cancer risk ES = 0.74 (95% CI = 0.67-0.82), p value = .000, but, moderate statistical heterogeneity (χ² = 42.73, p value = .011) was found. Due to the high mortality of colorectal cancer, it is important to identify effective preventive measures, especially those of a healthy lifestyle, such as a healthy diet.

A role for the vitamin D pathway in non-intestinal lesions in genetic and carcinogen models of colorectal cancer and in familial adenomatous polyposis

Vitamin D is implicated in the etiology of cancers of the gastrointestinal tract, usually characterized by alteration in the APC/β-catenin/TCF tumor suppressor pathway. The vitamin D receptor (VDR) is also implicated in cardiovascular and skin diseases as well as in immunity. Activated VDR can indirectly alter β-catenin nuclear localization and directly suppress β-catenin/TCF mediated transcriptional activity. We treated VDR null mice with the carcinogen azoxymethane (AOM) and generated mice bearing a mutated APC (hypomorph) on a VDR null background (Apc^1638N/+Vdr^−/−). VDR null mice do not develop GI or extra-colonic tumors but loss of VDR decreased intestinal tumor latency and increased progression to adenocarcinoma in both models. AOM treatment of VDR null mice also caused squamous cell carcinoma of the anus. Although levels and distribution of total or activated β-catenin in the epithelial component of tumors were unaffected by loss of VDR, β-catenin dependent cyclin D1 expression was affected suggesting a direct VDR effect on β-catenin co-activator activity. Extra-colonic mucosa manifestations in Apc^1638N/+Vdr^−/− animals included increased nuclear β-catenin in submucosal stromal cells, spleno- and cardiomegaly and large epidermoid cysts characteristic of the FAP variant, Gardner's syndrome. Consistent with this, SNPs in the VDR, vitamin D binding protein and CYP24 as well as mutations in APC distal to codon 850 were strongly associated with Gardners syndrome in a cohort of 457 FAP patients, This work suggests that alterations in the vitamin D/VDR axis are important in Gardner's syndrome, as well as in the etiology of anal cancer.

Occurrence of colorectal aberrant crypt foci depending on age and dietary patterns of patients

Background

Aberrant crypt foci (ACF) are commonly considered the early pre-cancerous lesions that can progress to colorectal cancer (CRC). The available literature data reveal that age, dietary factors and lifestyle can affect the development of several dozen percentages of malignant tumours, including CRC. In the present study, an attempt was made to assess the incidence and growth dynamics of ACF and to determine whether the type of diet affected the development and number of AFC.

Methods

Colonoscopy combined with rectal mucosa staining with 0.25% methylene blue was performed in 131 patients. On the day of examination, each patient completed a questionnaire regarding epidemiological data. According to their numbers, colorectal ACF were divided into three groups. The findings were analysed statistically. The Student’s t test and the U test were applied in order to determine the significance of differences of means and frequency of events in both groups. Statistica 7.1 and Excel 2010 were used.

Results

The single ACF occur in the youngest individuals (ACF < 5). Since the age of 38 years, the number of ACF gradually increases to show a decreasing tendency since the age of 60 years. The number of 5 < ACF < 10 occurs slightly later, since the age of 50 years, and dynamically increases reaching the maximum at the age of 62 years, subsequently the increase is proportional. ACF > 10 occur at a more advanced age (55 years) and their number gradually increases with age. The maximum number is observed at the age of 77 years.

In individuals not using high-fibre diets and with high intake of red meat, the probability of higher numbers of ACF increases. The probability of higher numbers of ACF (5 < ACF10) was observed in patients with colon diverticula. In patients with higher BMI, the number of ACF is higher.

Conclusion

Age significantly affects the number of colorectal ACF. The types of foods consumed can considerably increase the risk of colorectal ACF, which is particularly visible in individuals who do not regularly use high-fibre diets, those obese and with colon diverticula.

Is Timing Important? The Role of Diet and Lifestyle during Early Life on Colorectal Neoplasia

PURPOSE OF THE REVIEW

To summarize the current evidence on the most important dietary and lifestyle factors in colorectal carcinogenesis during different stages of a lifetime with special emphasis on studies investigating exposure during childhood, adolescence and young adulthood.

RECENT FINDINGS

A number of studies showed that independent of adult obesity, higher body fatness during childhood, adolescence and young adulthood is associated with risk of colorectal cancer later in life. In one large cohort study, the Nurses' Health Study II, adherence to a western pattern diet during adolescence was associated with higher risk of advanced adenoma. The current evidence relating consumption of individual foods and nutrients as well as physical activity during early life to colorectal cancer is sparse and less consistent, at least in part due to limitations in study design, such as sample size, limited data on potential confounders or lack of a validated dietary assessment instrument.

SUMMARY

As colorectal carcinogenesis is a long process and can take up to several decades to develop, early life risk factors may also be etiologically relevant. The recent rise in early-onset colorectal cancer incidence and mortality in the US, i.e., in individuals younger than 55 years at diagnosis, strongly supports that early life risk factors may influence colorectal carcinogenesis. Considering that the majority of colorectal cancers are preventable, there is an urgent need for well-designed investigations on the role of diet and lifestyle factors throughout the life course and risk of colorectal cancers.

Modeling eating behaviors: The role of environment and positive food association learning via a Ratatouille effect

Eating behaviors among a large population of children are studied as a dynamic process driven by nonlinear interactions in the sociocultural school environment. The impact of food association learning on diet dynamics, inspired by a pilot study conducted among Arizona children in Pre-Kindergarten to 8th grades, is used to build simple population-level learning models. Qualitatively, mathematical studies are used to highlight the possible ramifications of instruction, learning in nutrition, and health at the community level. Model results suggest that nutrition education programs at the population-level have minimal impact on improving eating behaviors, findings that agree with prior field studies. Hence, the incorporation of food association learning may be a better strategy for creating resilient communities of healthy and non-healthy eaters. A Ratatouille effect can be observed when food association learners become food preference learners, a potential sustainable behavioral change, which in turn, may impact the overall distribution of healthy eaters. In short, this work evaluates the effectiveness of population-level intervention strategies and the importance of institutionalizing nutrition programs that factor in economical, social, cultural, and environmental elements that mesh well with the norms and values in the community.

Copy number variation of E3 ubiquitin ligase genes in peripheral blood leukocyte and colorectal cancer

Given that E3 ubiquitin ligases (E3) regulate specific protein degradation in many cancer-related biological processes. E3 copy number variation (CNV) may affect the development and prognosis of colorectal cancer (CRC). Therefore, we detected CNVs of five E3 genes in 518 CRC patients and 518 age, gender and residence matched controls in China, and estimated the association between E3 gene CNVs and CRC risk and prognosis. We also estimated their interactions with environmental factors and CRC risk. We find a significant association between the CNVs of MDM2 and CRC risk (amp v.s. wt: odds ratio = 14.37, 95% confidence interval: 1.27, 163.74, P = 0.032), while SKP2 CNVs may significantly decrease CRC risk (del v.s. wt: odds ratio = 0.32, 95% confidence interval: 0.10, 1.00, P = 0.050). However, we find no significant association between the CNVs of other genes and CRC risk. The only significant gene-environment interaction effects are between SKP2 CNVs and consumption of fish and/or fruit (P = 0.014 and P = 0.035) and between FBXW7 CNVs and pork intake (P = 0.040). Finally, we find marginally significant association between β-TRCP CNVs and CRC prognosis (amp v.s. wt, hazard ratio = 0.42, 95% confidence interval: 0.19, 0.97, P = 0.050).

Association between dietary fibre intake with cancer and all-cause mortality among 15 740 adults: the National Health and Nutrition Examination Survey III

BACKGROUND

Few prospective studies have examined the longitudinal associations of total dietary fibre intake and water insoluble and soluble fibres with cancer and all-cause mortality. The present study aimed to examine these associations.

METHODS

We studied the effects of total dietary fibre intake and water insoluble and soluble fibres on cancer and all-cause mortality, using data from 15 740 adult participants [mean (SD) age: 44.53 (19.22) years, 46.60% male] in the National Health and Nutrition Examination Survey (NHANES) III, 1988-1994, who had completed a 24-h dietary recall. Death certificate data were obtained up to 2006. Participants had been followed for 13.74 years on average. Cox regression was used to estimate the hazard ratios (HRs) of total dietary, insoluble and soluble fibres on cancer and all-cause mortality, with the first quartile as the reference group, adjusted for demographics, lifestyle and dietary factors.

RESULTS

Relative to those in the first quartile of total fibre intake, only the third quartile was associated with all-cause mortality, with an adjusted HR of 0.87 [95% confidence interval (CI) = 0.79, 0.97, P = 0.021], and cancer mortality, with an adjusted HR of 0.77 (95% CI = 0.61, 0.99, P = 0.05). The third quartile of insoluble fibre intake was associated with cancer mortality, with an adjusted HR of 0.76 (95% CI = 0.60, 0.96, P = 0.023), and colorectal-anal cancer mortality (in grouped data as provided for public use), with an adjusted HR of 0.42 (95% CI = 0.19, 0.91, P = 0.03).

CONCLUSIONS

Dietary fibre showed protective benefits in terms of mortality risk. Investigating the mechanisms and components of dietary fibres underlying the different protective benefits remains an important consideration for research on fibre-mortality risk.

Mediterranean Diet and cancer risk: an open issue

The traditional Mediterranean Diet of the early 1960s meets the characteristics of an anticancer diet defined by the World Cancer Research Fund/American Institute for Cancer Research (WCRF/AIRC). A diet rich of whole grains, pulses, vegetables and fruits, limited in high-calorie foods (foods high in sugar or fat), red meat and foods high in salt, without sugary drinks and processed meat is recommended by the WCRF/AIRC experts to reduce the risk of cancer. The aim of this review was to examine whether Mediterranean Diet is protective or not against cancer risk. Three meta-analyses of cohort studies reported that a high adherence to the Mediterranean Diet significantly reduces the risk of cancer incidence and/or mortality. Nevertheless, the Mediterranean dietary pattern defined in the studies' part of the meta-analyses has qualitative and/or quantitative differences compared to the Mediterranean Diet of the early 1960s. Therefore, the protective role of the Mediterranean Diet against cancer has not definitely been established. In epidemiological studies, a universal definition of the Mediterranean Diet, possibly the traditional Mediterranean Diet of the early 1960s, could be useful to understand the role of this dietary pattern in cancer prevention.

Inverse associations of dietary fiber and menopausal hormone therapy with colorectal cancer risk in the Multiethnic Cohort Study

In the Multiethnic Cohort Study, we previously reported that dietary fiber intake was inversely associated with colorectal cancer risk in men only. In women, the inverse relationship was weaker and appeared to be confounded by menopausal hormone therapy (MHT). We re-examined this observation with a greatly increased power. Using Cox proportional hazards models, we analyzed data from 187,674 participants with 4,692 cases identified during a mean follow-up period of 16 years. In multivariable-adjusted models, dietary fiber intake was inversely associated with colorectal cancer risk in both sexes: HR = 0.73, 95% CI: 0.61-0.89 for highest vs. lowest quintile, ptrend  = 0.0020 in men and HR = 0.76, 95% CI: 0.62-0.91, ptrend  = 0.0067 in women. Postmenopausal women who ever used MHT had a 19% lower risk of colorectal cancer (95% CI: 0.74-0.89) compared with MHT never users. In a joint analysis of dietary fiber and MHT, dietary fiber intake was associated with a lower colorectal cancer risk in MHT never users (HR = 0.75, 95% CI: 0.59-0.95, ptrend  = 0.045), but did not appear to further decrease the colorectal cancer risk of MHT ever users (ptrend  = 0.11). Our results support the overall protective roles of dietary fiber and MHT against colorectal cancer and suggest that dietary fiber may not lower risk further among women who ever used MHT. If confirmed, these results would suggest that MHT and dietary fiber may share overlapping mechanisms in protecting against colorectal cancer.

Calcium supplementation for the prevention of colorectal adenomas: A systematic review and meta-analysis of randomized controlled trials

AIM: To determine the efficacy of calcium supplementation in reducing the recurrence of colorectal adenomas.

METHODS: We conducted a systematic review and meta-analysis of published studies. We searched PubMed, Scopus, the Cochrane Library, the WHO International Clinical Trials Registry Platform, and the ClinicalTrials.gov website, through December 2015. Randomized, placebo-controlled trials assessing supplemental calcium intake for the prevention of recurrence of adenomas were eligible for inclusion. Two reviewers independently selected studies based on predefined criteria, extracted data and outcomes (recurrence of colorectal adenomas, and advanced or “high-risk” adenomas), and rated each trial’s risk-of-bias. Between-study heterogeneity was assessed, and pooled risk ratio (RR) estimates with their 95% confidence intervals (95%CI) were calculated using fixed- and random-effects models. To express the treatment effect in clinical terms, we calculated the number needed to treat (NNT) to prevent one adenoma recurrence. We also assessed the quality of evidence using GRADE.

RESULTS: Four randomized, placebo-controlled trials met the eligibility criteria and were included. Daily doses of elemental calcium ranged from 1200 to 2000 mg, while the duration of treatment and follow-up of participants ranged from 36 to 60 mo. Synthesis of intention-to-treat data, for participants who had undergone follow-up colonoscopies, indicated a modest protective effect of calcium in prevention of adenomas (fixed-effects, RR = 0.89, 95%CI: 0.82-0.96; random-effects, RR = 0.87, 95%CI: 0.77-0.98; high quality of evidence). The NNT was 20 (95%CI: 12-61) to prevent one colorectal adenoma recurrence within a period of 3 to 5 years. On the other hand, the association between calcium treatment and advanced adenomas did not reach statistical significance (fixed-effects, RR = 0.92, 95%CI: 0.75-1.13; random-effects, RR = 0.92, 95%CI: 0.71-1.18; moderate quality of evidence).

CONCLUSION: Our results suggest a modest chemopreventive effect of calcium supplements against recurrent colorectal adenomas over a period of 36 to 60 mo. Further research is warranted.

Calcium, a Cell Cycle Commander, Drives Colon Cancer Cell Diffpoptosis

The story of the cell commonder, calcium, reaches into all corners of the cell and controls cell proliferation, differentiation, function, and even death. The calcium-driven eukaryotic revolution is one of the great turning points in the life history, happened about two billion years later when it was converted from a dangerous killer that had to be kept out of cell into the cell master which drives the cell. This review article will take the readers to a tour of tissues chosen to best show the calcium's many faces (proliferator, differentiator, and killer). The reader will first see calcium and its many helpers, such as the calcium-binding signaler protein calmodulin, directing the key events of the cell cycle. Then the tour will move onto the colon to show calcium driving the proliferation of progenitor cells, then the differentiation and ultimately the programmed death of their progeny. Moreover, the reader will learn of the striking disabling and bypassing of calcium-dependent control mechanisms during carcinogenesis. Finally, recommendations should be taken from the underlying mechanisms through which calcium masters the presistance, progression, and even apoptosis of colorectal cancer cells. Thus, this could be of great interest for designing of chemoprevention protocols.

Dietary approach to stop hypertension (DASH): diet components may be related to lower prevalence of different kinds of cancer: A review on the related documents

Background:

Dietary approaches to stop hypertension (DASH) eating plan is a healthy dietary pattern. Our object is to review surveys in the field of major components of DASH diet and different kinds of cancers.

Materials and Methods:

Our search result from PubMed search engine recruited to find related articles.

Results:

Adherence to the DASH diet components was significantly related to lower prevalence of various cancers due to their high content of fiber, nutrients, vitamins, mineral, and antioxidant capacity.

Conclusion:

In this review, positive association of DASH diet components and different cancers were observed. However, the exact association of DASH with cancers should be clarified in future longitudinal studies due to potential interaction among foods and nutrients.

Phytochemical Indicaxanthin Inhibits Colon Cancer Cell Growth and Affects the DNA Methylation Status by Influencing Epigenetically Modifying Enzyme Expression and Activity

BACKGROUND

Recently, we have shown anti-proliferative and pro-apoptotic effects of indicaxanthin associated with epigenetic modulation of the onco-suppressor p16INK4a in the human colon cancer cell line CACO2. In the present study, the epigenetic activity of indicaxanthin and the mechanisms involved were further investigated in other colorectal cancer cell lines.

METHODS

LOVO1, CACO2, HT29, HCT116, and DLD1 cells were used to evaluate the potential influence of consistent dietary concentrations of indicaxanthin on DNA methylation, and the epigenetic mechanisms involved were researched.

RESULTS

Indicaxanthin exhibited anti-proliferative activity in all cell lines but HT29, induced demethylation in the promoters of some methylation-silenced onco-suppressor genes involved in colorectal carcinogenesis (p16INK4a, GATA4, and ESR1), and left unchanged others which were basally hypermethylated (SFRP1 and HPP1). In apparent contrast, cell exposure to indicaxanthin increased DNMT gene expression, although indicaxanthin appeared to be an inhibitor of DNMT activity. Indicaxanthin also increased the expression of genes involved in DNA demethylation. Finally, an in silico molecular modelling approach suggested stable binding of indicaxanthin at the DNMT1 catalytic site.

CONCLUSIONS

Our findings contribute to new knowledge in the field of phytochemicals and specifically suggest dietary indicaxanthin as a potential epigenetic agent to protect colon cells against tumoral alterations.

Dietary fiber intake and risk of colorectal cancer and incident and recurrent adenoma in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial

BACKGROUND

Dietary fiber has been associated with a reduced risk of colorectal cancer. However, it remains unclear at which stage in the carcinogenic pathway fiber may act or which food sources of dietary fiber may be most beneficial against colorectal cancer development.

OBJECTIVE

The objective was to prospectively evaluate the association between dietary fiber intake and the risk of incident and recurrent colorectal adenoma and incident colorectal cancer.

DESIGN

Study participants were identified from the intervention arm of the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. Participants received flexible sigmoidoscopy at baseline and 3 or 5 y after. Dietary fiber intake was measured by using a self-reported dietary questionnaire. The colorectal cancer, incident adenoma, and recurrent adenoma analyses were based on 57,774, 16,980, and 1667 participants, respectively. Unconditional logistic regression was used to assess the risk of incident and recurrent adenoma, and Cox proportional hazards models were used to assess the risk of colorectal cancer across categories of dietary fiber intake, with adjustment for potential confounders.

RESULTS

Elevated total dietary fiber intake was associated with a significantly reduced risk of incident distal colorectal adenoma (ORhighest vs. lowest tertile of intake: 0.76; 95% CI: 0.63, 0.91; P-trend = 0.003) but not recurrent adenoma (P-trend = 0.67). Although the association was not statistically significant for colorectal cancer overall (HR: 0.85; 95% CI: 0.70, 1.03; P-trend = 0.10), a reduced risk of distal colon cancer was observed with increased total fiber intake (HR: 0.62; 95% CI: 0.41, 0.94; P-trend = 0.03). Protective associations were most notable for fiber originating from cereals or fruit.

CONCLUSIONS

This large, prospective study within a population-based screening trial suggests that individuals consuming the highest intakes of dietary fiber have reduced risks of incident colorectal adenoma and distal colon cancer and that this effect of dietary fiber, particularly from cereals and fruit, may begin early in colorectal carcinogenesis. This trial was registered at clinicaltrials.gov as NCT01696981.

Vegetable consumption and colorectal cancer risk: an evaluation based on a systematic review and meta-analysis among the Japanese population

OBJECTIVE

The association between vegetable consumption and colorectal cancer risk remains unclear and may differ by region. We performed a systematic review and meta-analysis of epidemiologic studies on this issue among the Japanese population.

METHODS

A systematic review and meta-analysis was performed by searching MEDLINE through PubMed and the Ichushi database for cohort and case-control studies that were published by the end of December 2014. Associations were evaluated based on their magnitude and the strength of the evidence. Meta-analysis was performed by using the random effects model to estimate the summary relative risk with 95% confidence interval according to the study design. The final judgment was made based on a consensus of the research group members with consideration for both epidemiological evidence and biological plausibility.

RESULTS

We identified six cohort studies and 11 case-control studies on vegetable intake and colorectal cancer among the Japanese population. Of the cohort studies, one study showed a weak inverse association with colon cancer and another study showed a weak positive association with rectal cancer in men, but other studies found no associations between vegetable consumption and colon and rectal cancers. With regard to case-control studies, one study found a strong inverse association with colon cancer, and three studies showed a weak-to-strong inverse association with rectal cancer. In meta-analysis, the summary relative risk (95% confidence interval) for the highest vs. the lowest categories of vegetable consumption were 1.00 (0.92-1.10) and 0.75 (0.59-0.96) for cohort and case-control studies, respectively.

CONCLUSIONS

There was insufficient evidence to support an association between intake of vegetables and the risk of colorectal cancer among the Japanese population.