Primary prevention of colorectal cancer: lifestyle, nutrition, exercise

Sex Difference of Colon Adenoma Pathway and Colorectal Carcinogenesis

Colorectal cancer (CRC) is one of the most common causes of cancer morbidity in both sexes but shows sex differences. First, sex-specific differences in tumor recurrence and survival rates have been reported. For example, the development of CRC is found about 1.5 times higher and 4-8 years earlier in males compared to females, suggesting the protective role of estrogen in the disease. Furthermore, female patients have a higher risk of developing right-sided (proximal) colon cancer than male patients, which is known to have more aggressive clinical character compared to left-sided (distal) colon cancer. That is, left and right CRCs show differences in carcinogenic mechanism, that the chromosomal instability pathway is more common in left colon cancer while the microsatellite instability and serrated pathways are more common in right colon cancer. It is thought that there are sex-based differences on the background of carcinogenesis of CRC. Sex differences of CRC have two aspects, sexual dimorphism (biological differences in hormones and genes) and gender differences (non-biological differences in societal attitudes and behavior). Recently, sex difference of colon adenoma pathway and sexual dimorphism in the biology of gene and protein expression, and in endocrine cellular signaling in the CRC carcinogenesis have been accumulated. In addition, behavioral patterns can lead to differences in exposure to risk factors such as drinking or smoking, diet and physical activity. Therefore, understanding sex/gender-related biological and sociocultural differences in CRC risk will help in providing strategies for screening, treatment and prevention protocols to reduce the mortality and improve the quality of life. In this review, sex/gender differences in colon adenoma pathway and various aspects such as clinicopathological, biological, molecular, and socio-cultural aspects of CRC were described.

Validity of pathological diagnosis for early colorectal cancer in genetic background

BACKGROUND

This study aimed to investigate the validity of pathological diagnosis of early CRC (E-CRC) from the genetic background by comparing data of E-CRC to colorectal adenoma (CRA) and The Cancer Genome Atlas (TCGA) on advanced CRC (AD-CRC).

METHODS

TCGA data on AD-CRC were studied in silico, whereas by next-generation sequencer, DNA target sequences were performed for endoscopically obtained CRA and E-CRC samples. Immunohistochemical staining of mismatch repair genes and methylation of MLH1 was also performed. The presence of oncogenic mutation according to OncoKB for the genes of the Wnt, MAPK, and cell-cycle-signaling pathways was compared among CRA, E-CRC, and AD-CRC.

RESULTS

The study included 22 CRA and 30 E-CRC lesions from the Chiba University Hospital and 212 AD-CRC lesions from TCGA data. Regarding the number of lesions with driver mutations in the Wnt and cell-cycle-signaling pathways, E-CRC was comparable to AD-CRC, but was significantly greater than CRA. CRA had significantly more lesions with a driver mutation for the Wnt signaling pathway only, versus E-CRC.

CONCLUSIONS

In conclusion, the definition of E-CRC according to the Japanese criteria had a different genetic profile from CRA and was more similar to AD-CRC. Based on the main pathway, it seemed reasonable to classify E-CRC as adenocarcinoma. The pathological diagnosis of E-CRC according to Japanese definition seemed to be valid from a genetic point of view.

Home-based, supervised, and mixed exercise intervention on functional capacity and quality of life of colorectal cancer patients: a meta-analysis

This systematic review and meta-analysis of randomized controlled trials tested the effects of home-based, supervised, or mixed exercise interventions on the functional capacity (FC) and quality of life (QoL) in colorectal cancer patients. A literature search was performed using the PubMed, Embase, Cochrane, and Medline databases. Two reviewers screened the literature through March 10, 2021 for studies related to exercise and colorectal cancer. Of the 1161 screened studies in the initial search, 13 studies met the eligibility criteria (home-based = 6 studies; supervised or mixed = 7 studies). Overall, 706 patients were enrolled in the trials, and 372 patients were submitted to home-based, supervised, or mixed exercise intervention. The overall results from the main meta-analysis showed a significant effect regarding supervised or mixed intervention (6 studies; p = 0.002; I² = 43%; PI 0.41–1.39); however, no significant effect was observed for home-based intervention (5 studies; p = 0.05; I² = 25%; PI − 0.34–0.76). A sensitivity analysis based on studies with intervention adherence ≥ 80% (home-based = 3 studies; supervised or mixed = 4 studies) revealed that home-based intervention or intervention entirely supervised or with some level of supervision (mixed) are effective in improving the QoL and FC of CRC patients. In summary, this meta-analysis verified that supervised and home-based exercise can modify QoL and FC when intervention adherence ≥ 80%. Regardless of the supervision characteristics, future RCTs are strongly encouraged to provide a detailed description of the exercise variables in physical interventions for CRC prescription. This perspective will allow a refined exercise prescription for patients with CRC, mainly according to their clinical status.

Both increased and decreased sleep duration over time are associated with subsequent cancer development

PURPOSE

Changes in sleep duration have been reported to correlate with lifestyle-related diseases in humans. However, equivalent studies regarding the effects of sleep on cancer progression are lacking. This study aimed to determine whether or not increase or decrease in sleep duration over time is associated with subsequent cancer development.

METHODS

A large-scale, retrospective cohort study was conducted at a preventive medicine health center at a general community hospital in Tokyo, Japan. All participants who underwent health checkups at the hospital between January 2005 and December 2018 were included. The primary study outcome was development of any type of cancer according to the slope of sleep duration over the study period. The Cox proportional hazard model was used to adjust the outcomes based on potential covariates.

RESULTS

Of 15,025 participants, 7,692 (51.2%) were men. The mean age (standard deviation) was 66.0 (7.5) years. During a median follow-up of 2,588 (interquartile range: 1,583-3,695) days, 1,396 (9.3%) participants developed cancer of any type. Compared to hazard ratio in the stable sleep duration group (- 0.1 to + 0.1 h/day in 1 year), both greatly decreased (less than - 0.2 h/day in 1 year; hazard ratio (HR), 2.13; 95% confidence interval (CI), 1.72-2.62) and increased (more than + 0.2 h/day in 1 year; HR, 2.55; 95% CI 2.14-3.04) groups showed significantly higher hazard ratio for the development of any type of cancer.

CONCLUSION

Both increased and decreased sleep duration over time are associated with subsequent cancer development.

Resting heart rate is associated with colorectal advanced adenoma

Background and aims

Resting heart rate is an independent predictor of colorectal cancer (CRC) development and CRC-related mortality. However, little is known about the relationship between resting heart rate and colorectal adenoma development. We aimed to investigate this association in a population who underwent screening colonoscopy.

Methods

Among 39,021 patients who underwent both electrocardiogram and screening colonoscopy during routine health examinations at the Seoul National University Bundang Hospital, Health Promotion Center, Korea from January 2014 to July 2019, 1,344 patients had advanced adenoma. We performed 1:1 propensity score (PS) matching to establish a control group that mitigated the confounding effects of age and sex. We performed multivariate logistic regression analyses to identify the independent risk factors of advanced adenoma development.

Results

Resting heart rate was significantly higher in the advanced adenoma group than in the control group. The prevalence of advanced polyp increased across the quartiles of resting heart rate. Patients with higher resting heart rates were more likely to be older, smokers, and have increased blood pressure and DM and less likely to engage in active exercises than those with lower resting heart rates. Patients with higher resting heart rates had higher serum glucose, triglyceride, hemoglobin A1C, and insulin levels and lower high-density lipoprotein cholesterol levels. Patients with resting heart rate in the highest quartile (≥71 bpm) still showed significantly increased odds ratio (OR) of advanced adenoma development (OR: 1.379, 95% confidence interval: 1.099–1.731, p = 0.006).

Conclusions

High resting heart rate was a meaningful independent risk factor of advanced adenoma development.

Lipid profiling of mouse intestinal organoids for studying APC mutations

Inactivating mutations including both germline and somatic mutations in the adenomatous polyposis coli (APC) gene drives most familial and sporadic colorectal cancers. Understanding the metabolic implications of this mutation will aid to establish its wider impact on cellular behaviour and potentially inform clinical decisions. However, to date, alterations in lipid metabolism induced by APC mutations remain unclear. Intestinal organoids have gained widespread popularity in studying colorectal cancer and chemotherapies, because their 3D structure more accurately mimics an in vivo environment. Here, we aimed to investigate intra-cellular lipid disturbances induced by APC gene mutations in intestinal organoids using a reversed-phase ultra-high-performance liquid chromatography mass spectrometry (RP-UHPLC-MS)-based lipid profiling method. Lipids of the organoids grown from either wild-type (WT) or mice with APC mutations (Lgr5-EGFP-IRES-CreERT2Apcfl/fl) were extracted and analysed using RP-UHPLC-MS. Levels of phospholipids (e.g. PC(16:0/16:0), PC(18:1/20:0), PC(38:0), PC(18:1/22:1)), ceramides (e.g. Cer(d18:0/22:0), Cer(d42:0), Cer(d18:1/24:1)) and hexosylceramides (e.g. HexCer(d18:1/16:0), HexCer(d18:1/22:0)) were higher in Apcfl/fl organoids, whereas levels of sphingomyelins (e.g. SM(d18:1/14:0), SM(d18:1/16:0)) were lower compared with WT. These observations indicate that cellular metabolism of sphingomyelin was up-regulated, resulting in the cellular accumulation of ceramides and production of HexCer due to the absence of Apcfl/fl in the organoids. Our observations demonstrated lipid profiling of organoids and provided an enhanced insight into the effects of the APC mutations on lipid metabolism, making for a valuable addition to screening options of the organoid lipidome.

The Protective Role of Urtica dioica Seed Extract Against Azoxymethane-Induced Colon Carcinogenesis in Rats

The aim of this study was to investigate the protective role of Urtica dioica seed (UDS) extract against azoxymethane (AOM)-induced colon carcinogenesis in rats. Thirty-two male Wistar albino rats were divided into four groups: Control, AOM, AOM + UDS, and UDS. The AOM and AOM + UDS groups were induced by AOM (15 mg/kg body weight) subcutaneously once a week for 10 weeks. AOM + UDS and UDS groups additionally received fed with pellets included 30 ml/kg UDS extract. At the end of the trial, blood and colon tissue samples were taken from the rats following necropsy. The gross and histopathological findings revealed that the administration of UDS extract significantly decreased lesions including aberrant cript foci, adenoma, and adenocarcinoma formation both numerically and dimensionally. Immunohistochemically, slight CEA and COX-2, strong Caspase-3 immune-expressions were detected in the group AOM + UDS compared to AOM group. Biochemical examinations indicated that a markedly increase in the malondialdehyde and fluctuated antioxidant defense system constituents levels such as reduced glutathione, glutathione s-transferase, glutathione peroxidase, superoxide dismutase were restored in AOM + UDS group. These results reveal that the UDS may act as a chemopreventive dietary agent, inducing apoptosis, resulting in a significant reduction of colon carcinogenesis.

Proteogenomics of Colorectal Cancer Liver Metastases: Complementing Precision Oncology with Phenotypic Data

Hotspot testing for activating KRAS mutations is used in precision oncology to select colorectal cancer (CRC) patients who are eligible for anti-EGFR treatment. However, even for KRAS^wildtype tumors anti-EGFR response rates are <30%, while mutated-KRAS does not entirely rule out response, indicating the need for improved patient stratification. We performed proteogenomic phenotyping of KRAS^wildtype and KRAS^G12V CRC liver metastases (mCRC). Among >9000 proteins we detected considerable expression changes including numerous proteins involved in progression and resistance in CRC. We identified peptides representing a number of predicted somatic mutations, including KRAS^G12V. For eight of these, we developed a multiplexed parallel reaction monitoring (PRM) mass spectrometry assay to precisely quantify the mutated and canonical protein variants. This allowed phenotyping of eight mCRC tumors and six paired healthy tissues, by determining mutation rates on the protein level. Total KRAS expression varied between tumors (0.47–1.01 fmol/µg total protein) and healthy tissues (0.13–0.64 fmol/µg). In KRAS^G12V-mCRC, G12V-mutation levels were 42–100%, while one patient had only 10% KRAS^G12V but 90% KRAS^wildtype. This might represent a missed therapeutic opportunity: based on hotspot sequencing, the patient was excluded from anti-EGFR treatment and instead received chemotherapy, while PRM-based tumor-phenotyping indicates the patient might have benefitted from anti-EGFR therapy.

Diet, Microbiota, and Colorectal Cancer

The intestinal epithelium is a very dynamic tissue under a high regenerative pressure, which makes it susceptible to malignant transformation. Proper integration of various cell signaling pathways and a balanced cross talk between different cell types composing the organ are required to maintain intestinal homeostasis. Dysregulation of this balance can lead to colorectal cancer (CRC). Here, we review important insights into molecular and cellular mechanisms of CRC. We discuss how perturbation in complex regulatory networks, including the Wnt, Notch, BMP, and Hedgehog pathways; and how variations in inflammatory signaling, nutrients, and microbiota can affect intestinal homeostasis contributing to the malignant transformation of intestinal cells.

Oxidative Stress and Inflammation: What Polyphenols Can Do for Us?

Oxidative stress is viewed as an imbalance between the production of reactive oxygen species (ROS) and their elimination by protective mechanisms, which can lead to chronic inflammation. Oxidative stress can activate a variety of transcription factors, which lead to the differential expression of some genes involved in inflammatory pathways. The inflammation triggered by oxidative stress is the cause of many chronic diseases. Polyphenols have been proposed to be useful as adjuvant therapy for their potential anti-inflammatory effect, associated with antioxidant activity, and inhibition of enzymes involved in the production of eicosanoids. This review aims at exploring the properties of polyphenols in anti-inflammation and oxidation and the mechanisms of polyphenols inhibiting molecular signaling pathways which are activated by oxidative stress, as well as the possible roles of polyphenols in inflammation-mediated chronic disorders. Such data can be helpful for the development of future antioxidant therapeutics and new anti-inflammatory drugs.

Screening behaviors, health beliefs, and related factors of first-degree relatives of colorectal cancer patients with ongoing treatment in Turkey

BACKGROUND

Colorectal cancer (CRC) is one of the most common cancers. Family history is an important risk factor; first-degree relatives (FDRs) are most at risk. Studies are needed to determine the screening behavior of FDRs and factors affecting their health behaviors.

OBJECTIVE

The purpose of this study was to investigate the screening behaviors, health beliefs, and related factors of FDRs (parent, sibling, or child) of CRC patients undergoing treatment.

METHODS

A cross-sectional design was used with 400 FDRs of patients undergoing treatment at 2 hospitals in Turkey. Data were collected using the Colorectal Cancer Risk Questionnaire and the Turkish Colorectal Cancer Health Belief Model Scale.

RESULTS

A slight majority of the participants were male (51.3%), with a mean of age 37.7 years. The rate of having at least 1 colonoscopy in FDRs was 22.2%. First-degree relatives reported high perceived confidence-benefits scores on average (mean, 48.4 ± 5.2) and high perceived barrier scores on average (mean, 15.5 ± 3.8). Health motivation of FDRs was the strongest predictor of their having a colonoscopy (odds ratio, 7.50; 95% confidence interval, 3.40-16.5).

CONCLUSIONS

First-degree relatives have a low rate of having a colonoscopy but are more likely to have had this procedure if they have strong health motivation.

IMPLICATIONS FOR PRACTICE

Nurses working with CRC patients must develop strategies to increase FDRs' knowledge of, awareness of, and motivation for CRC screening tests. Risk counseling of FDRs during the treatment period might increase screening rates.

Effects of Physical Activity on Risk of Colorectal Cancer: A Case-control Study

Background:

The prevalence of colorectal cancer (CRC) is rapidly increasing in Iran. It holds the most prevalent cancer after skin, breast, and gastric cancers among the Iranian population. The current study was designed to investigate the effects of leisure time, occupational and household physical activity as well as exercise on the risk of CRC in the Iranian population.

Methods:

In this population-based case–control study, 100 individuals with a recent diagnosis of CRC who were eligible for the study were recruited between 2006 and 2008. The control groups were selected from patients’ companions (excluding first- and second-degree relatives) without past history of cancer or any physical disability. Physical activity of the participants was evaluated using a Kriska retrospective physical activity questionnaire. The relation between CRC and physical activity was assessed via logistic regression model and calculating the odds ratio (OR) as well as a confidence interval (CI) of 95%.

Results:

According to the findings, the adjusted OR of occupational (OR = 0.98, 95%, CI: 0.95–1.02) and house holding physical activities (OR = 1.03, 95% CI: 0.99–1.08) were not significantly different between the case and control groups for women (P > 0.05). The risk of CRC shows a significant reduction in individuals with moderate leisure physical activities compared to those with minimal activities (OR = 0.82, CI 95%: 0.73–0.98).

Conclusions:

The study suggests that the risk of CRC will decrease in individuals with higher leisure physical activities (especially with an increase in hours of brisk walking during the day).

State of polyphenols in the drying process of fruits and vegetables

This review presents an overview of drying technologies and its impact on the polyphenol content of vegetables and fruits. Polyphenols contribute to many health benefits and can act as antioxidants. Specifically an increased intake of polyphenols has been shown to decrease the incidence of cardiovascular disease; furthermore, it has been shown to help reduce the risk of neurodegenerative diseases in humans. Many researchers have reported on the effect of different drying techniques on the polyphenol content in fruits and vegetables. Polyphenol degradation mechanisms proposed in literature and pretreatments that potentially lead to higher retention of polyphenols during drying are also discussed.

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.

Genetic architecture of colorectal cancer

Colorectal cancer (CRC) is a complex disease that develops as a consequence of both genetic and environmental risk factors. A small proportion (3-5%) of cases arise from hereditary syndromes predisposing to early onset CRC as a result of mutations in over a dozen well defined genes. In contrast, CRC is predominantly a late onset 'sporadic' disease, developing in individuals with no obvious hereditary syndrome. In recent years, genome wide association studies have discovered that over 40 genetic regions are associated with weak effects on sporadic CRC, and it has been estimated that increasingly large genome wide scans will identify many additional novel genetic regions. Subsequent experimental validations have identified the causally related variant(s) in a limited number of these genetic regions. Further biological insight could be obtained through ethnically diverse study populations, larger genetic sequencing studies and development of higher throughput functional experiments. Along with inherited variation, integration of the tumour genome may shed light on the carcinogenic processes in CRC. In addition to summarising the genetic architecture of CRC, this review discusses genetic factors that modify environmental predictors of CRC, as well as examples of how genetic insight has improved clinical surveillance, prevention and treatment strategies. In summary, substantial progress has been made in uncovering the genetic architecture of CRC, and continued research efforts are expected to identify additional genetic risk factors that further our biological understanding of this disease. Subsequently these new insights will lead to improved treatment and prevention of colorectal cancer.

The potential for fungal biopesticides to reduce malaria transmission under diverse environmental conditions

The effectiveness of conventional malaria vector control is being threatened by the spread of insecticide resistance. One promising alternative to chemicals is the use of naturally-occurring insect-killing fungi. Numerous laboratory studies have shown that isolates of fungal pathogens such as Beauveria bassiana can infect and kill adult mosquitoes, including those resistant to chemical insecticides.Unlike chemical insecticides, fungi may take up to a week or more to kill mosquitoes following exposure. This slow kill speed can still reduce malaria transmission because the malaria parasite itself takes at least eight days to complete its development within the mosquito. However, both fungal virulence and parasite development rate are strongly temperature-dependent, so it is possible that biopesticide efficacy could vary across different transmission environments.We examined the virulence of a candidate fungal isolate against two key malaria vectors at temperatures from 10-34 °C. Regardless of temperature, the fungus killed more than 90% of exposed mosquitoes within the predicted duration of the malarial extrinsic incubation period, a result that was robust to realistic diurnal temperature variation.We then incorporated temperature sensitivities of a suite of mosquito, parasite and fungus life-history traits that are important determinants of malaria transmission into a stage-structured malaria transmission model. The model predicted that, at achievable daily fungal infection rates, fungal biopesticides have the potential to deliver substantial reductions in the density of malaria-infectious mosquitoes across all temperatures representative of malaria transmission environments.Synthesis and applications. Our study combines empirical data and theoretical modelling to prospectively evaluate the potential of fungal biopesticides to control adult malaria vectors. Our results suggest that Beauveria bassiana could be a potent tool for malaria control and support further development of fungal biopesticides to manage infectious disease vectors.

The chemopreventive potential of Curcuma purpurascens rhizome in reducing azoxymethane-induced aberrant crypt foci in rats

Curcuma purpurascens BI. rhizome, a member of the Zingiberaceae family, is a popular spice in Indonesia that is traditionally used in assorted remedies. Dichloromethane extract of C. purpurascens BI. rhizome (DECPR) has previously been shown to have an apoptosis-inducing effect on colon cancer cells. In the present study, we examined the potential of DECPR to prevent colon cancer development in rats treated with azoxymethane (AOM) (15 mg/kg) by determining the percentage inhibition in incidence of aberrant crypt foci (ACF). Starting from the day immediately after AOM treatment, three groups of rats were orally administered once a day for 2 months either 10% Tween 20 (5 mL/kg, cancer control), DECPR (250 mg/kg, low dose), or DECPR (500 mg/kg, high dose). Meanwhile, the control group was intraperitoneally injected with 5-fluorouracil (35 mg/kg) for 5 consecutive days. After euthanizing the rats, the number of ACF was enumerated in colon tissues. Bax, Bcl-2, and proliferating cell nuclear antigen (PCNA) protein expressions were examined using immunohistochemical and Western blot analyses. Antioxidant enzymatic activity was measured in colon tissue homogenates and associated with malondialdehyde level. The percentage inhibition of ACF was 56.04% and 68.68% in the low- and high-dose DECPR-treated groups, respectively. The ACF inhibition in the treatment control group was 74.17%. Results revealed that DECPR exposure at both doses significantly decreased AOM-induced ACF formation, which was accompanied by reduced expression of PCNA. Upregulation of Bax and downregulation of Bcl-2 suggested the involvement of apoptosis in the chemopreventive effect of DECPR. In addition, the oxidative stress resulting from AOM treatment was significantly attenuated after administration of DECPR, which was shown by the elevated antioxidant enzymatic activity and reduced malondialdehyde level. Taken together, the present data clearly indicate that DECPR significantly inhibits ACF formation in AOM-treated rats and may offer protection against colon cancer development.

Diet and physical activity intervention in colorectal cancer survivors: a feasibility study

Purpose

Evidence that lifestyle factors are associated with better outcomes in colorectal cancer (CRC) survivors highlights the need for behaviour change interventions. This study examined feasibility and acceptability, and provided an indication of behavioural impact, of a telephone-based, multimodal health behaviour intervention for CRC survivors.

Method

Participants were recruited from five London hospitals. Patients (n = 29) who had recently completed treatment for CRC participated in a 12 week intervention. Behavioural goals were to increase physical activity (PA) and fruit and vegetable (F&V) intake, and reduce consumption of red/processed meat and alcohol. Self-report measures of PA and diet were completed in all patients, supplemented by objective measures in a sub-set.

Results

Uptake of the study when patients were approached by a researcher was high (72%), compared with 27% contacted by letter. Methods for identifying eligible patients were not optimal. Study completion rate was high (79%), and completers evaluated the intervention favourably. Significant improvements were observed in objectively-measured activity (+70 min/week; p = .004). Gains were seen in diet: +3 F&V portions a day (p < .001), −147 g of red meat a week (p = .013), −0.83 portions of processed meat a week (p = .002). Changes in serum vitamin levels were not statistically significant, but the small sample size provides limited power. Clinically meaningful improvement in quality of life (p < .001) was observed.

Conclusion

An intervention combining print materials and telephone consultations was feasible and acceptable, and associated with improvements in PA, diet and quality of life.

Bioavailability, bioactivity and impact on health of dietary flavonoids and related compounds: an update

There is substantial interest in the role of plant secondary metabolites as protective dietary agents. In particular, the involvement of flavonoids and related compounds has become a major topic in human nutrition research. Evidence from epidemiological and human intervention studies is emerging regarding the protective effects of various (poly)phenol-rich foods against several chronic diseases, including neurodegeneration, cancer and cardiovascular diseases. In recent years, the use of HPLC-MS for the analysis of flavonoids and related compounds in foods and biological samples has significantly enhanced our understanding of (poly)phenol bioavailability. These advancements have also led to improvements in the available food composition and metabolomic databases, and consequently in the development of biomarkers of (poly)phenol intake to use in epidemiological studies. Efforts to create adequate standardised materials and well-matched controls to use in randomised controlled trials have also improved the quality of the available data. In vitro investigations using physiologically achievable concentrations of (poly)phenol metabolites and catabolites with appropriate model test systems have provided new and interesting insights on potential mechanisms of actions. This article will summarise recent findings on the bioavailability and biological activity of (poly)phenols, focusing on the epidemiological and clinical evidence of beneficial effects of flavonoids and related compounds on urinary tract infections, cognitive function and age-related cognitive decline, cancer and cardiovascular disease.

Physical activity in relation to quality of life in newly diagnosed colon cancer patients: a 24-month follow-up

PURPOSE

Self-reported health status in cancer patients is an independent predictor of medical outcomes. This study investigated the association between changes in recreational physical activity in colon cancer survivors and quality of life (QoL) across a 24-month follow-up beginning at diagnosis.

METHODS

Patients (n = 453) diagnosed with stage II colon cancer were recruited from the North Carolina Central Cancer Registry from 2009 to 2011. Patients were interviewed annually about health behaviors (e.g., dietary intake, physical activity, alcohol and tobacco use), socioeconomic variables, and treatment. To index QoL, the Functional Assessment of Cancer Therapy-Colorectal (FACT-C) and Short Form-12 (SF-12) were utilized.

RESULTS

Baseline vigorous exercise showed a positive correlation with the Functional Assessment of Cancer Therapy-General (FACT-G) Colorectal Cancer Scale (CCS) (β = 0.15, 95% CI 0.07-0.23), FACT-C (β = 0.39, 95% CI 0.06-0.72), and Trial Outcome Index (TOI) (β = 0.28, 95% CI 0.01-0.55). Race modified the association between vigorous activity and the FACT-G (P interaction = 0.010), FACT-C (P interaction = 0.020), TOI (P interaction < 0.010), and the PCS (P interaction < 0.010). As compared to no change, increasing physical activity over a 24-month period following diagnosis significantly improved scores from the FACT-G (β = 3.13, 95% CI 0.48-5.77, P trend = 0.054), FACT-C (β = 3.51, 95% CI 0.35-6.68, P trend = 0.08) TOI (β = 2.46, 95% CI 0.16-4.75, P trend = 0.04), and PCS of the SF-12 (β = 3.28, 95% CI 0.93-5.63, P trend < 0.01).

CONCLUSION

Vigorous exercise is a significant predictor of higher QoL in stage II colon cancer patients. Patients with increased recreational physical activity have significantly improved QoL over 24 months following diagnosis.

Inonotus Obliquus Suppresses Proliferation of Colorectal Cancer Cells and Tumor Growth in Mice Models by Downregulation of β-Catenin/NF-κB-Signaling Pathways

Chaga mushroom (Inonotus obliquas) has been used as a folk remedy for several illnesses including gastrointestinal disorders. We recently reported the potent anti-inflammatory effect of chaga extract in experimental colitis. However, its effects on colorectal cancer (CRC) have not been clearly elucidated. We investigated the effects of an aqueous extract of Inonotus obliquus (IOAE) in vitro in HCT116 and DLD1 cell lines and in vivo for adenoma in APCMin/+ mice and colitis-associated colon cancer in AOM/DSS-treated mice. Results show that IOAE suppressed the proliferation of both cell lines, and inhibited the growth of intestinal polyps in APCMin/+ and colon tumors in AOM/DSS-treated mice. IOAE induced mitochondrial intrinsic pathway of apoptosis, autophagy, and S phase cell cycle arrest. IOAE suppressed the expression levels of iNOS and Cox-2 and mRNA levels of pro-inflammatory cytokines (IL-6, IL-1β, TNF-a and IFN-γ) in the intestine of mice models. IOAE suppressed the nuclear levels of β-catenin and inhibited its downstream targets (cyclin D1 and c-Myc) along with CRC oncogene CDK8. IOAE inhibited the expression of NF-κB at cytoplasmic and nuclear levels. Our results demonstrate that IOAE possess potent anti-inflammatory and anti-proliferative properties through downregulation of Wnt/β-catenin and NF-κB pathways. Considering recent anticancer approaches involving natural products with minimal side effects, we advocate that Inonotus obliquus could be a beneficial supplement in prevention of colorectal cancer.

Pleiotropic effects of genistein in metabolic, inflammatory, and malignant diseases

Genistein is a soy-derived biologically active isoflavone that exhibits diverse health-promoting effects. An increasing body of evidence shows that genistein influences lipid homeostasis and insulin resistance, counteracts inflammatory cytokines, and possesses antidiabetic properties. Genistein also impedes cancer progression by promoting apoptosis, inducing cell cycle arrest, modulating intracellular signaling pathways, and inhibiting angiogenesis and metastasis of neoplastic cells. This review summarizes the pleiotropic functions of genistein in common health disorders such as metabolic syndrome, chronic inflammatory diseases, and cancer. In the current era of uncontrolled health expenditure, a focus on the clinical development of nutritional agents with the capacity to prevent a variety of common health disorders is needed. As a micronutrient that exerts multifaceted effects ranging from antidiabetic to anticarcinogenic functions, genistein should be clinically developed further for use in the prevention and treatment of a variety of health disorders.

Comparison of dietary and lifestyle habits among stage III and metastatic colorectal cancer patients: findings from CALGB 89803 and CALGB 80405

Self-administered questionnaires were completed by patients undergoing chemotherapy for stage III colon cancer (n=1095) and metastatic colorectal cancer (n=875). We describe the prevalence of a wide-range of health-related dietary patterns and lifestyle behaviors among colorectal cancer patients with stage III and metastatic disease and report notable similarities in these 2 cohorts.

BACKGROUND

Cancer patients often pursue lifestyle and dietary changes with the aim to improve outcomes. Using data from 2 large National Cancer Institute-sponsored clinical trials, we report on the dietary and lifestyle practices of patients receiving therapy for stage III colon or metastatic colorectal cancer.

PATIENTS AND METHODS

Self-administered questionnaires were completed by patients undergoing chemotherapy for stage III colon cancer (n=1095) and metastatic colorectal cancer (n=875). Descriptive statistical analyses were performed to evaluate anthropometrics, diet, and lifestyle in each cohort.

RESULTS

Median body mass index was comparable for stage III and metastatic patients (27.3 vs. 26.5 kg/m2). Stage III patients reported a modestly higher median level of physical activity than metastatic patients (4.6 vs. 3.4 metabolic equivalent task-hours per week). Ten percent of stage III and 9% of metastatic patients reported ongoing cigarette use. Avoidance of alcohol was reported by 47% of stage III and 43% of metastatic patients. Dietary patterns for both groups were comparable with more than 80% of stage III and metastatic patients failing to meet the recommended daily intake of vegetables, fruits, and milk products. Usage of at least 2 multivitamins per week was reported by 49% of stage III and 40% of metastatic patients. Two percent of stage III and 5% of metastatic patients reported vitamin D supplement use.

CONCLUSIONS

We observed notable similarities in dietary and lifestyle behaviors between stage III colon and metastatic colorectal cancer patients actively receiving chemotherapy. Future research should aim to elucidate the effect of these behaviors on patient outcomes.

Monascus-fermented red mold rice exhibits cytotoxic effect and induces apoptosis on human breast cancer cells

Red mold rice (RMR) is a traditional food and folk medicine to Asian people and has recently become a popular health supplement. RMR has been shown to have some anticancer activities, although the mechanism for inducing cell death of human breast cancer cells is still not fully understood. In this study, bioactive extracts of RMR fermented by Monascus purpureus NTU 803 were analyzed for effects on apoptosis induction in human breast cancer cells. The RMR ethanol extract and ethyl acetate extract contain monacolin K, total phenols, and flavonoids, the three components that have been reported to have anticancer activity. Red mold rice extracts (RMRE) exhibited selective cytotoxic effect on MCF-7 cells. RMRE treatment induced apoptosis and cell cycle arrest at G2/M phase. Apoptosis was confirmed by annexin V-fluorescein isothiocyanate (FITC)/propidium iodide staining, the observation of characteristic chromatin condensation, nuclear DNA fragmentation, and poly(ADP-ribose) polymerase cleavage. Furthermore, the RMRE-induced apoptosis in MCF-7 cells may occur through a mitochondria-dependent pathway while triggering an appropriate balance of bax/bcl-2 and activation of caspase-9 and caspase-3 in a time-dependent manner. To conclude, RMRE exhibits direct cytotoxic and proapoptotic effects on MCF-7 cells and could be considered as a potential functional food for breast cancer prevention.

Overview of biomarkers in metastatic colorectal cancer: tumour, blood and patient-related factors

During the last 20 years there have been major therapeutic developments in colorectal cancer (CRC) with the introduction of multiple novel therapeutic agents into routine clinical practice. This has improved survival in both the adjuvant and advanced disease settings. However, improvements have come with substantial increases in expense to the community and potential toxicity to the patient. There has been substantial research to identify tumour factors in CRC that predict treatment response and survival outcomes. This research has identified clinically useful predictive biomarkers to aid clinical decision making, such as the presence or absence of KRAS gene mutations which can determine the benefit of using epidermal growth factor receptor (EGFR) inhibiting antibodies. However, less attention has been paid to the identification and impact of predictive patient-derived factors such as age, gender and the presence of comorbid conditions or evidence of a systemic inflammatory response. In this article, the current concepts of tumour and patient-related predictive factors in CRC management are reviewed.

Genistein, a soya isoflavone, prevents azoxymethane-induced up-regulation of WNT/β-catenin signalling and reduces colon pre-neoplasia in rats

The present study aimed to explore the role(s) of the soya isoflavone genistein (GEN) in preventing the development of colon pre-neoplasia, using Wingless/int (WNT)/β-catenin as a molecular marker of colon abnormality. Specifically, the effects on the WNT/β-catenin signalling pathway from GEN were examined by using an azoxymethane (AOM)-induced rat colon cancer model. Male Sprague-Dawley rats were fed a control (CTL), a soya protein isolate (SPI) or a GEN diet from gestation to 13 weeks of age. The first sampling was conducted at 7 weeks of age for pre-AOM analysis. The remaining rats were injected with AOM at 7 weeks of age. The descending colon was collected 6 weeks later for the evaluation of aberrant crypt foci (ACF), gene expression and nuclear protein accumulation. AOM injection induced aberrant nuclear accumulation of β-catenin in the CTL group but not in the SPI or GEN group. Moreover, the WNT target genes Cyclin D1 and c-Myc were repressed by SPI and GEN. Meanwhile, SPI and GEN suppressed the expression of WNT signalling genes including Wnt5a, Sfrp1, Sfrp2 and Sfrp5 to the similar level to that of the pre-AOM period. Rats fed SPI and GEN had a decreased number of total aberrant crypts. GEN feeding also resulted in a reduced number of ACF with N = 3 per foci. The reduction of WNT/β-catenin signalling was correlated with the decrease in total aberrant crypts. By testing WNT/β-catenin signalling as a biomarker of colon carcinogenic potential, we showed the novel role of GEN as a suppressor of carcinogen-induced WNT/β-catenin signalling in preventing the development of early colon neoplasia.

Dietary, endocrine, and metabolic factors in the development of colorectal cancer

INTRODUCTION

Colorectal cancer is the third cause of death in industrialized countries. Genetic susceptibility and diet are determinant of cancer risk and tumor behavior. Variation in cancer incidence among and within populations with similar dietary patterns suggests that an individual response may reflect interactions with genetic factors, which may modify gene, protein, and metabolite expression patterns. Nutrigenomics, defined as the interaction between nutrition and an individual genome, will likely provide important clues about responders and non-responders to nutritional intervention.

DISCUSSION

Epidemiological and experimental studies suggest a protective role of some normal components of daily diet (fish oil, milk, and vegetables), estrogens, and phytoestrogens in colorectal cancer. The effect of estrogen seems to be mediated by their binding to estrogen receptor beta (ER-β), one of the two estrogen receptors with high affinity for these hormones. Very recently, the demonstration of an involvement of ER-β in the development of adenomatous polyps of the colon has also been documented, suggesting the use of selective ER-β agonists in primary colorectal cancer prevention. Phytoestrogens are plant-derived compounds that structurally and functionally act as estrogen agonists in mammals. They are characterized by a higher binding affinity to ER-β as compared to estrogen receptor alpha (ER-α), the other estrogen receptor subtype. These biological characteristics explain why the administration of phytoestrogens does not produce the classical side effects associated to estrogen administration (cerebro- and cardiovascular accidents, higher incidence of endometrial and breast cancer) and makes these substances potential candidates for colorectal cancer prevention.

Metabolic syndrome and leptin are associated with adverse pathological features in male colorectal cancer patients

AIM

Metabolic syndrome (MetS) describes a clustering of factors including central obesity, hypertension and raised plasma glucose, triglycerides and high-density lipoprotein (HDL) cholesterol. Central obesity is associated with a risk for colorectal cancer, but the impact of MetS on colorectal cancer biology and outcomes is unclear.

METHOD

A prospective observational study of colorectal cancer patients was carried out in an Irish population. Patients underwent metabolic and anthropometric assessment before treatment, including measurement of serum hormones and adipokines and CT measurement of visceral fat. MetS was defined according to the International Diabetes Federation definition(3) .

RESULTS

One-hundred and thirty consecutive colorectal cancer patients (66 men and 64 women) were recruited. MetS was diagnosed in 38% patients compared with the population norms reported at 21%(21) . Male patients had a significantly greater visceral fat area compared with female patients. MetS was associated with node-positive disease (P = 0.026), percentage nodal involvement (P = 0.033) and extramural vascular invasion (P = 0.049) in male patients but no significant association was observed in female patients. HDL cholesterol was also significantly associated with a more advanced pathological stage (P = 0.014) and node-positive disease (P = 0.028). Leptin was associated with nodal status (P = 0.036), microvascular invasion (P = 0.054), advanced pathological stage (P = 0.046) and more advanced Dukes stage (P = 0.042).

CONCLUSION

We report a high prevalence of MetS and visceral obesity in a colorectal cancer population. MetS and plasma leptin are associated with a more aggressive tumour phenotype in male patients only.

Colorectal Chemoprevention Pilot Study (SWOG-9041), randomized and placebo controlled: the importance of multiple luminal lesions

BACKGROUND

Colorectal cancer is common worldwide and chemoprevention has the potential of reducing the number of individuals who may suffer and perish from this disease.

METHODS

A randomized placebo controlled pilot study in colorectal cancer patients was performed using calcium carbonate as the test agent in a multi-institutional oncology study group.

RESULTS

Two hundred twenty volunteers were randomized in the study. The primary goals of compliance, accrual, and toxicity monitoring are presented. Presence of multiple adenomas at study entry and subsequent development of metachronous adenomas were recorded and found to be associated with synchronous adenomas. The secondary endpoint of recurrent adenomas indicated lower rates of new adenoma in the volunteers randomized to the calcium group.

CONCLUSION

This pilot study indicates the feasibility of enrolling survivors of colorectal cancer as study volunteers in a colorectal neoplasm chemoprevention clinical trial and oral calcium continues to be a potentially effective drug in reducing colorectal adenomas.

DNA methylation patterns in blood of patients with colorectal cancer and adenomatous colorectal polyps

Colorectal cancer (CRC) screening rates are currently suboptimal. Blood-based screening could improve rates of earlier detection for CRC and adenomatous colorectal polyps. In this study, we evaluated the feasibility of plasma-based detection of early CRC and adenomatous polyps using array-mediated analysis methylation profiling of 56 genes implicated in carcinogenesis. Methylation of 56 genes in patients with Stages I and II CRC (N=30) and those with adenomatous polyps (N=30) were compared with individuals who underwent colonoscopy and were found to have neither adenomatous changes nor CRC. Composite biomarkers were developed for adenomatous polyps and CRC, and their sensitivity and specificity was estimated using five-fold cross validation. Six promoters (CYCD2, HIC1, PAX 5, RASSF1A, RB1 and SRBC) were selected for the biomarker, which differentiated CRC patients and controls with 84% sensitivity and 68% specificity. Three promoters (HIC1, MDG1 and RASSF1A) were selected for the biomarker, which differentiated patients with adenomatous polyps and controls with sensitivity of 55% and specificity of 65%. Methylation profiling of plasma DNA can detect early CRC with significant accuracy and shows promise as a methodology to develop biomarkers for CRC screening.

Polycyclic aromatic hydrocarbons and digestive tract cancers: a perspective

Cancers of the colon are most common in the Western world. In majority of these cases, there is no familial history and sporadic gene damage seems to play an important role in the development of tumors in the colon. Studies have shown that environmental factors, especially diet, play an important role in susceptibility to gastrointestinal (GI) tract cancers. Consequently, environmental chemicals that contaminate food or diet during preparation become important in the development of GI cancers. Polycyclic aromatic hydrocarbons (PAHs) are one such family of ubiquitous environmental toxicants. These pollutants enter the human body through consumption of contaminated food, drinking water, inhalation of cigarette smoke, automobile exhausts, and contaminated air from occupational settings. Among these pathways, dietary intake of PAHs constitutes a major source of exposure in humans. Although many reviews and books on PAHs and their ability to cause toxicity and breast or lung cancer have been published, aspects on contribution of diet, smoking and other factors toward development of digestive tract cancers, and strategies to assess risk from exposure to PAHs have received much less attention. This review, therefore, focuses on dietary intake of PAHs in humans, animal models, and cell cultures used for GI cancer studies along with epidemiological findings. Bioavailability and biotransformation processes, which influence the disposition of PAHs in body and the underlying causative mechanisms of GI cancers, are also discussed. The existing data gaps and scope for future studies is also emphasized. This information is expected to stimulate research on mechanisms of sporadic GI cancers caused by exposure to environmental carcinogens.

Beyond standard adjuvant therapy for colon cancer: role of nonstandard interventions

Epidemiologic and scientific research indicates that diet and other lifestyle factors have a significant influence on the risk of developing colorectal cancer. Obesity, consumption of red meat, a Western pattern diet, alcohol, and smoking influence one's risk of developing colorectal cancer while physical activity, vitamin D, postmenopausal estrogen use, aspirin, and nonsteroidal anti-inflammatory drugs (NSAIDs) decrease one's risk. Until recently, it was largely unknown if any of these modifiable factors influence the outcomes of patients already diagnosed with colorectal cancer. However, data are emerging of factors that may influence disease recurrences and mortality for colorectal cancer survivors. Prospective observational studies have shown that increased exercise after diagnosis and avoidance of a Western pattern diet are associated with reduced risk of cancer recurrence and improved overall survival in early-stage colorectal cancer after standard therapy. Patients with class II and III obesity (body mass index [BMI] ≥35 kg/m(2)) have a modestly increased risk of recurrence. Regular use of aspirin or cyclooxygenase (COX)-2 inhibitors decrease recurrence rates and increase serum vitamin D levels. In contrast, change of weight after diagnosis or smoking status (never, past, or current) are not associated with outcomes after diagnosis. The data supporting these observations will be reviewed, potential mechanisms of actions will be discussed, and the next steps forward will be proposed.

Cancer profile of migrants from the Former Soviet Union in Germany: incidence and mortality

This study compares cancer mortality and incidence of ethnic German migrants from the Former Soviet Union (FSU) in Germany. Data were obtained from two migrant cohorts residing in the federal state of North Rhine-Westphalia (NRW) (n = 34,393) and Saarland (n = 18,619). Vital status of the NRW cohort was ascertained through local population registries. Causes of death were obtained from the NRW statistical office or from local health offices. Cancer incidence of the Saarland cohort was derived from the Saarland cancer registry using record linkage. From 1990 to 2005, we observed 708 cancer deaths and 586 incident cancer cases. In males, both cancer incidence and cancer mortality were similar to the German population. Female cancer incidence and mortality were lower, the latter significantly. Site-specific standardized mortality and incidence ratios showed great variation in comparison to Germans and were remarkably similar to each other for most sites. Lung cancer was elevated among males, but lower among females. Stomach cancer was higher contrasting with lower ratios for prostate cancer, male colorectal cancer, and female breast cancer. Results confirm that FSU-migrants suffer from cancers, which may be prevented by prevention programs. Furthermore, we cannot conclude a different health-seeking behavior compared to Germans.

Curcumin suppresses intestinal polyps in APC Min mice fed a high fat diet

Colorectal cancer (CRC) is a leading cause of cancer deaths in the United States. Various risk factors have been associated with CRC including increasing age and diet. Epidemiological and experimental studies have implicated a diet high in fat as an important risk factor for colon cancer. High fat diets can promote obesity resulting in insulin resistance and inflammation and the development of oxidative stress, increased cell proliferation, and suppression of apoptosis. Because of the high consumption of dietary fats, especially saturated fats, by Western countries, it is of interest to see if non-nutrient food factors might be effective in preventing or delaying CRC in the presence of high saturated fat intake. Curcumin (Curcuma longa), the main yellow pigment in turmeric, was selected to test because of its reported anti-tumor activity. APC Min mice, which develop intestinal polyps and have many molecular features of CRC, were fed a diet containing 35% pork fat, 33% sucrose, and a protein and vitamin mineral mixture (HFD) with or without 0.5% curcumin. These cohorts were compared to APC Min mice receiving standard rodent chow (RC) with 8% fat. APC Min mice fed the HFD for 3 months had a 23% increase in total number of polyps compared to APC Min mice on RC. Curcumin was able to significantly reverse the accelerated polyp development associated with the HFD suggesting it may be effective clinically in helping prevent colon cancer even when ingesting high amounts of fatty foods. The anti-tumor effect of curcumin was shown to be associated with enhanced apoptosis and increased efficiency of DNA repair. Since curcumin prevented the gain in body weight seen in APC Min mice ingesting the HFD, modulation of energy metabolism may also be a factor.

Genistein attenuates WNT signaling by up-regulating sFRP2 in a human colon cancer cell line

Colorectal cancer (CRC) is a leading fatal carcinoma worldwide. Our goal was to investigate the effects of genistein on WNT signaling, which is involved in colon epithelial cell growth and apoptosis. Human colon cancer cell line DLD-1 was treated for four days with 75 μmol/L genistein. Decreased nuclear β-catenin and increased phospho- β-catenin accumulation was detected, showing a change in WNT signaling. Reverse transcriptase-polymerase chain reaction analysis showed increased sFRP2 (a WNT pathway antagonist) mRNA expression following the genistein treatment. Methylation selective polymerase chain reaction showed decreased methylation in two CpG islands of the sFRP2 gene following genistein treatment, similar to the effect of 5-aza-cytidine, a demethylation agent. We observed reduced DLD-1 cell viability and increased apoptosis with genistein treatment. Genistein inhibits β-catenin-mediated WNT signaling through increasing sFRP2 gene expression by demethylating its silenced promoter in colon cancer cell line DLD-1.

Dietary patterns and the risk of colorectal adenomas: the Black Women's Health Study

BACKGROUND

Colorectal adenomas are benign lesions that may be precursors to colorectal cancer. No studies of African American women have investigated dietary patterns and the risk of developing colorectal adenomas. We examined data from the Black Women's Health Study to determine whether dietary patterns are associated with the risk of developing colorectal adenomas.

METHODS

This is a prospective cohort study of 59,000 participants followed biennially since 1995. During 155,414 person-years of follow-up from 1997 to 2007 among women who had had at least one screening colonoscopy, 620 incident cases of colorectal adenomas were identified. By using Cox regression models, we obtained incidence rate ratios (IRR) for colorectal adenoma in relation to quintiles of each of two dietary patterns, adjusting for other colorectal adenoma risk factors.

RESULTS

Two dietary patterns, Western and prudent, were utilized to assess the association between dietary intake and adenoma risk. The highest quintile of prudent diet, relative to the lowest quintile, was significantly associated with 34% lower colorectal adenoma risk overall (IRR = 0.66; 95% CI, 0.50-0.88; P(trend) < 0.01). Higher scores on the Western pattern were associated with a higher risk of developing colorectal adenoma (IRR = 1.42; 95% CI, 1.09-1.85 for the highest quintile relative to the lowest; P(trend) = 0.01).

CONCLUSION

Our findings suggest that African American women may be able to reduce their risk of developing colorectal adenomas by following a prudent dietary pattern and avoiding a more Western pattern.

IMPACT

A dietary modification could have a strong impact in colorectal adenoma prevention in African American women.

Polyphenols and human health: prevention of disease and mechanisms of action

Polyphenols are found ubiquitously in plants and their regular consumption has been associated with a reduced risk of a number of chronic diseases, including cancer, cardiovascular disease (CVD) and neurodegenerative disorders. Rather than exerting direct antioxidant effects, the mechanisms by which polyphenols express these beneficial properties appear to involve their interaction with cellular signaling pathways and related machinery that mediate cell function under both normal and pathological conditions. We illustrate that their interactions with two such pathways, the MAP kinase (ERK, JNK, p38) and PI3 kinase/Akt signaling cascades, allow them to impact upon normal and abnormal cell function, thus influencing the cellular processes involved in the initiation and progression of cancer, CVD and neurodegeneration. For example, their ability to activate ERK in neurons leads to a promotion of neuronal survival and cognitive enhancements, both of which influence the progression of Alzheimer’s disease, whilst ERK activation by polyphenols in vascular endothelial cells influences nitric oxide production, blood pressure and ultimately CVD risk. The main focus of this review is to provide an overview of the role that polyphenols play in the prevention of cancer, cardiovascular disease and neurodegeneration. We present epidemiological data, human intervention study findings, as well as animal and in vitro studies in support of these actions and in each case we consider how their actions at the cellular level may underpin their physiological effects.

Increasing incidence of rectal cancer in patients aged younger than 40 years: an analysis of the surveillance, epidemiology, and end results database

BACKGROUND

The incidence of rectal cancer in the United States in young patients is considered to be low. Underestimating this incidence may result in a failure to diagnose younger patients with rectal cancer in a timely manner.

METHODS

The authors conducted a retrospective cohort study using Surveillance, Epidemiology, and End Results (SEER) cancer registry data. A total of 7661 patients with colon, rectal, and rectosigmoid cancer who were diagnosed at age <40 years were identified between 1973 and 2005. The change in incidence over time for colon and rectal/rectosigmoid cancer was calculated and the annual percent change for anatomic subsites of colorectal cancer compared.

RESULTS

SEER data demonstrated an increase in the incidence of rectal cancer without any increase in colon cancer (annual percent change of 2.6% vs -0.2%). The difference was statistically significant and extended to rectosigmoid cancer, but not cancer of the sigmoid colon or descending colon (annual percent change of 2.2% vs 0.4% and -2.8%, respectively). Joinpoint analysis of the slope of the curve of rectal and rectosigmoid cancer incidence identified the beginning of the increase to be 1984. All races and both sexes demonstrated similar statistically significant increases in the incidence of rectal and rectosigmoid cancer.

CONCLUSIONS

The incidence of rectal and rectosigmoid cancer appears to be increasing in patients aged <40 years. Patients presenting with rectal bleeding or other alarming signs or symptoms should be evaluated with this finding in mind.

Dietary feeding of grape seed extract prevents intestinal tumorigenesis in APCmin/+ mice

Chemopreventive effects and associated mechanisms of grape seed extract (GSE) against intestinal/colon cancer development are largely unknown. Herein, we investigated GSE efficacy against intestinal tumorigenesis in APC(min/+) mice. Female APC(min/+) mice were fed control or 0.5% GSE (wt/wt) mixed AIN-76A diet for 6 weeks. At the end of the experiment, GSE feeding decreased the total number of intestinal polyps by 40%. The decrease in polyp formation in the small intestine was 42%, which was mostly in its middle (51%) and distal (49%) portions compared with the proximal one. GSE also decreased polyp growth where the number of polyps of 1 to 2 mm in size decreased by 42% and greater than 2 mm in size by 71%, without any significant change in polyps less than 1 mm in size. Immunohistochemical analyses of small intestinal tissue samples revealed a decrease (80%-86%) in cell proliferation and an increase (four- to eight-fold) in apoptosis. GSE feeding also showed decreased protein levels of cyclooxygenase-2 (COX-2) (56%-64%), inducible nitric oxide synthase (iNOS) (58%-60%), and beta-catenin (43%-59%) but an increased Cip1/p21-positive cells (1.9- to 2.6-fold). GSE also decreased cyclin D1 and c-Myc protein levels in small intestine. Together, these findings show the chemopreventive potential of GSE against intestinal polyp formation and growth in APC(min/+) mice, which was accompanied with reduced cell proliferation and increased apoptosis together with down-regulation in COX-2, iNOS, beta-catenin, cyclin D1, and c-Myc expression, but increased Cip1/p21. In conclusion, the present study suggests potential usefulness of GSE for the chemoprevention of human intestinal/colorectal cancer.

Modifier-concept of colorectal carcinogenesis: Lipidomics as a technical tool in pathway analysis

In the modifier concept of intestinal carcinogenesis, lipids have been established as important variables and one focus is given to long-chain fatty acids. Increased consumption of long-chain fatty acids is in discussion to modify the development of colorectal carcinoma in humans. Saturated long-chain fatty acids, in particular, are assumed to promote carcinogenesis, whereas polyunsaturated forms are likely to act in the opposite way. At present, the molecular mechanisms behind these effects are not well understood. Recently, it has been demonstrated by lipidomics and associated molecular techniques, that activation and metabolic channeling of long-chain fatty acids are important mechanisms to modify colorectal carcinogenesis. In this Editorial, an overview about the present concept of long-chain fatty acids and its derivatives in colorectal carcinogenesis as well as technical algorithms in lipid analysis is given.

Dietary fat-influenced development of colon neoplasia in Apc Min mice exposed to benzo(a)pyrene

Colorectal cancer, responsible for 50,000 deaths per year, is a contributing factor for considerable mortalities in the United States. Consumption of well-done red meat and saturated fats rich in polycyclic aromatic hydrocarbons may be one of the causative factors for sporadic colon cancer. The objective of this study was to investigate whether the formation of colon tumors in adult Apc(Min) mice was influenced by the ingestion of different types of fat containing benzo(a)pyrene [B(a)P], a polycyclic aromatic hydrocarbon compound. Treatment consisted of 50 and 100 microg B(a)P/kg body weight dissolved in peanut or coconut oil (representatives of unsaturated and saturated fats, respectively) administered daily to six-week-old male Apc(Min) mice via oral gavage for sixty days. At the end of exposure, mice were sacrificed; jejunum and colons were retrieved and preserved in 10% formalin for observation for gross pathological changes. An increased prevalence of adenomas in colons of mice that ingested B(a)P through saturated dietary fat compared to unsaturated fat and controls (p < .05) was noticed. Interestingly, we also observed adenomas with high-grade dysplasia in the B(a)P + saturated fat group, and these incidences were frequent at the 100 microg/kg B(a)P dose. On the other hand, the B(a)P-alone and unsaturated-fat groups did not show significant differences in the numbers of adenomas and invasive tumors in the both jejunum and the colon. Our studies established that dietary fat, especially saturated fat, potentiates the development of colon tumors caused by B(a)P in the Apc(Min) mouse.