The role of nutrition in cancer development and prevention

Long Follow-Up Times Weaken Observational Diet-Cancer Study Outcomes: Evidence from Studies of Meat and Cancer Risk

For years, prospective cohort studies of diet and cancer incidence have reported smaller effects than do retrospective case-control (CC) studies. The differences have been attributed to problems with CC studies, including dietary recall bias, poor matching of cases and controls, and confounding. The hypothesis evaluated here is that long follow-up periods between ascertainment of diet and cancer incidence weaken the findings. Prospective studies of cancer incidence with respect to serum 25-hydroxyvitamin D concentration have already shown reduced benefit of higher concentrations for longer follow-up periods. Evaluating that hypothesis for dietary factors involved searching the journal literature for meta-analyses of red meat and processed meat and cancer incidence. I used findings from observational studies for bladder, breast, colorectal, and gastric cancers. To evaluate the effect of duration of follow-up time, I used two approaches. First, I plotted the relative risks for CC studies for gastric cancer with respect to consumption of 100 g/day of red meat and for bladder cancer for 50 g/day of processed meat against the interval between the dietary data and cancer incidence. Second, I compared nested CC studies of meat and cancer incidence for five breast cancer studies and one colorectal cancer study. Both approaches yielded an inverse correlation between interval or follow-up time and relative risk. My findings strongly suggest that diet near time of cancer diagnosis is more important than for longer intervals, that results from meta-analyses should be revised when possible with appropriate adjustments for duration of follow-up, and that dietary guidelines be revised accordingly.

Microbiota as the unifying factor behind the hallmarks of cancer

The human microbiota is a complex ecosystem that colonizes body surfaces and interacts with host organ systems, especially the immune system. Since the composition of this ecosystem depends on a variety of internal and external factors, each individual harbors a unique set of microbes. These differences in microbiota composition make individuals either more or less susceptible to various diseases, including cancer. Specific microbes are associated with cancer etiology and pathogenesis and several mechanisms of how they drive the typical hallmarks of cancer were recently identified. Although most microbes reside in the distal gut, they can influence cancer initiation and progression in distant tissues, as well as modulate the outcomes of established cancer therapies. Here, we describe the mechanisms by which microbes influence carcinogenesis and discuss their current and potential future applications in cancer diagnostics and management.

Are chemical compounds in medical mushrooms potent against colorectal cancer carcinogenesis and antimicrobial growth?

After cardiovascular diseases, cancer is the second main cause of death globally. Mushrooms have been demonstrated to contain amalgamation with properties capable of inhibiting carcinogenesis and microbial growth, principally secondary metabolites such as quinolones, steroids, terpenes, anthraquinones, and benzoic acid derivatives among others. This study aimed to substantiate their potency concerning colon cancer carcinogenesis and antimicrobial growth. A systematic search of important literature was performed considering all the articles published until April 2022. Screening was performed by searching the BMC Springer, Elsevier, Embase, Web of Science, Ovid, and MEDLINE databases. In addition, Google Scholar was used to supplement information. Titles and abstracts that matched the established criteria were selected for full-text article scrutiny and subsequently used in the updated present review. Bioactive compounds present in medicinal mushrooms such as ascorbic acid, organic acids, flavonoids, polysaccharides, glycosides, phenols, linoleic acid, grifolin, and tocopherols among other compounds play a key role in suppressing the proliferation of cancerous cells and selectively act as antibacterial and antifungal agents. These metabolites actively scavenge oxygen free radicals, hydroxyl radicals, and nitrite radicals that would otherwise increase the risks of the growth and development of cancerous cells. Mushrooms' bioactive compounds and metabolites actively inhibit nuclear factor-kappa activation, protein kinase B processes, and ultimately the expression of Cyclooxygenases 2 in cancerous cells. Medicinal mushrooms should be considered as alternative natural chemo-preventive agents in the global fight against colon cancer and the evolution of drug-resistant pathogenic microorganisms, as they exhibit robust potency. They have not been reported to exhibit adverse harmful effects compared to synthetic chemotherapies, yet they have been reported to demonstrate significant beneficial effects.

Prognostic Value of CRP-Albumin-Lymphocyte (CALLY) Index in Patients Undergoing Surgery for Oral Cavity Cancer

Background: The prognostic value of the CRP-albumin-lymphocyte index (CALLY index) was analyzed in patients with oral cavity squamous cell carcinoma (OSCC) undergoing curative surgery.

Methods: We retrospectively included 279 patients who were diagnosed as having primary OSCC and being treated with surgery. The optimal cutoff for the preoperative CALLY index was identified by considering the area under the receiver operating characteristic curve; subsequently, the discriminatory ability of the cutoff was determined. We employed Kaplan-Meier analysis and the log-rank test to elucidate associations between the CALLY index and survival outcomes. We identified prognostic variables by using the Cox proportional hazards model. Finally, we devised a nomogram based on the CALLY index for predicting individualized survival.

Results: The cutoff value of the CALLY index was determined to be 0.65. A CALLY index < 0.65 exhibited a significant association with pathological aggressiveness as well as shorter overall and disease-free survival (OS and DFS, both P < 0.001). A low CALLY index was an independent risk factor for short OS and DFS [hazard ratio = 3.816; 95% confidence interval (CI) 2.393-6.086; P < 0.001; and hazard ratio = 2.103; 95% CI 1.451-3.049; P < 0.001, respectively] in multivariate Cox analysis. The prognostic nomogram based on the CALLY index yielded accurate predictions of OS, as revealed by a concordance index of 0.797.

Conclusions: The preoperative CALLY index is easy and inexpensive to calculate and, in patients with OSCC, can be a valuable prognostic biomarker. The CALLY-index-based nomogram established in this study provides accurate survival predictions.

Prevalence and Factors Associated with Self-Reported Vision Disability among the Elderly in Malaysia: Findings from National Health and Morbidity Survey (NHMS) 2018

Introduction

Disability has adverse effects on health, wellbeing, and life quality. Vision disorder is one of the top-ranked causes of disability in the elderly population. This study aims to determine the prevalence and factors associated with vision disability among the elderly in Malaysia. Methodology. Data collection from National Health and Morbidity Survey (NHMS) 2018 was obtained. This survey focused on elderly health by using two-stage stratified cluster sampling design. The Washington Group Extended Question Set on Functioning (WG ES-F) was used to determine the vision disability. The data were analyzed using SPSS version 21.0 utilizing a complex sample design with multivariable logistic regression analysis to determine the prevalence and associated factors to vision disability.

Results

A total of 3,977 elderly completed the vision disability questionnaire. The overall prevalence of vision disability among those who were 60 years old and above was 4.5%. Multiple logistic regression revealed that no formal education (AOR: 6.69, 95% CI: 1.52, 29.49), only primary education (AOR: 4.26, 95% CI: 1.01, 18.03), unemployed/retiree or homemaker (AOR: 3.25, 95% CI: 1.79, 5.89), hypertension (AOR: 1.45, 95% CI: 1.00, 2.09), and malnourished elderly (AOR: 2.84, 95% CI: 1.76, 461) had higher odds for having vision disability.

Conclusion

The findings suggest that a low education level, unemployment, hypertension, and malnourishment are significant risk factors for VD among Malaysia's elderly. Strengthening awareness campaigns to increase VD awareness and provide high-quality rehabilitation services must target specific groups, such as the elderly with a low level of education and the unemployed. Empower primary healthcare providers with the knowledge and skills necessary to improve the quality of eye care delivery and expand eye screening in settling VD issues nationally.

Dietary and Environmental Determinants of Oesophageal Cancer in Arsi Zone, Oromia, Central Ethiopia: A Case-Control Study

PURPOSE

Oesophageal cancer is ranked 5th of all types of malignancies in Ethiopia and highly prevalent in the Arsi Zone. However, no study was conducted to elucidate the dietary and environmental determinants of oesophageal cancer in the Arsi Zone.

METHODS

A matched case-control study was conducted from June 1, 2019, to June 30, 2020. A total of 104 cases and 208 controls were interviewed. Data were collected using food frequency questionnaires (structured questionnaires). Binary and multiple logistic regression analyses were conducted to check the association between independent and dependent variables. Adjusted odds ratios and the corresponding 95% confidence intervals were estimated for the strength of association. Statistical significance was declared at a P-value of <0.05.

RESULTS

In multivariable logistic regression, drinking very hot coffee (AOR=5.1,[95% CI: (1.95, 13.71), drinking large volume of coffee (AOR=4.9, [95% CI: (2.03, 12.17), very hot porridge (AOR= 3.1,[95% CI: (1.38,7.03) and eating porridge fast (AOR=7.0, [95% CI: (2.48, 20.14), low intake of dairy products (AOR=6.0, [95% CI: (2.29, 15.95), cooking food in sleeping room (AOR=3.7, [95% CI: (1.22, 11.39), exposure to x-ray (AOR=9.4,[95% CI: (3.94, 22.82), nonalcohol homemade drinks (AOR=5.4,[95% CI: (1.97, 15.14), use of chemical containers (AOR=3.4, [95% CI: (1.48, 8.23) were determinants of oesophageal cancer.

CONCLUSION

Coffee temperature, coffee drinking volume, porridge consumption temperature, porridge consumption speed, dairy products intake patterns, food cooking place, x-ray exposure, nonalcohol homemade drink, and use of chemical containers were independent determinants of the increased risk of oesophageal cancer in the study community.

Increased dietary and circulating lycopene are associated with reduced prostate cancer risk: a systematic review and meta-analysis

BACKGROUND

Prostate cancer (PCa) is the fifth leading cause of cancer-related deaths worldwide. Many epidemiological studies have investigated the association between prostate cancer and lycopene, however, results have been inconsistent. This study aims to determine the impact of dietary and circulating concentrations of lycopene on PCa risk and to investigate potential dose-response associations.

METHODS

We conducted a systematic review and dose-response meta-analysis for the for the association between dietary and circulating lycopene and PCa risk. Eligible studies were published before 1 December 2016 and were identified from PubMed, Web of Science and the Cochrane Library. We estimated pooled relative risk ratios (RR) and 95% confidence intervals (CI) using random and fixed effects models. Linear and nonlinear dose-response relationships were also evaluated for PCa risk.

RESULTS

Forty-two studies were included in the analysis, which included 43 851 cases of PCa reported from 692 012 participants. Both dietary intake (RR=0.88, 95% CI: 0.78-0.98, P=0.017) and circulating concentrations (RR=0.88, 95% CI: 0.79-0.98, P=0.019) of lycopene were significantly associated with reduced PCa risk. Sensitivity analyses within the dose-response analysis further revealed a significant linear dose-response for dietary lycopene and PCa risk such that PCa decreased by 1% for every additional 2 mg of lycopene consumed (P=0.026). Additionally, PCa risk decreased by 3.5 to 3.6% for each additional 10 μgdl^-1 of circulating lycopene in the linear and nonlinear models respectively (p_linear=0.004, p_nonlinear=0.006). While there were no associations between lycopene and advanced PCa, there was a trend for protection against PCa aggressiveness (RR=0.74, 95% CI: 0.55-1.00, P=0.052).

CONCLUSIONS

Our data demonstrate that higher dietary and circulating lycopene concentrations are inversely associated with PCa risk. This was accompanied by dose-response relationships for dietary and circulating lycopene. However, lycopene was not associated with a reduced risk of advanced PCa. Further studies are required to determine the mechanisms underlying these associations.

Cancers in Australia in 2010 attributable to inadequate consumption of fruit, non-starchy vegetables and dietary fibre

Objectives

To estimate the number and proportion of cancers occurring in Australia in 2010 attributable to consumption deficits in fruit, non-starchy vegetables and dietary fibre.

Methods

We estimated the population attributable fraction (PAF) for cancers causally associated with inadequate intake of fruit and non-starchy vegetables (oral cavity, pharynx, oesophageal squamous cell carcinoma, stomach, larynx); inadequate intake of fruit (lung); and insufficient intake of fibre (colorectum). We used standard formulae incorporating prevalence of exposure (1995 National Nutrition Survey) and relative risks from independent studies.

Results

Overall, 1,555 (1.4% of all) and 311 (0.3% of all) cancers were attributable to inadequate intakes of fruit and non-starchy vegetables, respectively. A further 2,609 colorectal cancers (18% of colorectal) were attributable to insufficient fibre intake. If Australians increased their fibre intake by eating the recommended daily intakes of fruit and vegetables, an estimated 1,293 (8.8%) colorectal cancers could be prevented.

Conclusions

One in six colorectal cancer cases was attributable to inadequate intake of dietary fibre and about 1,800 cancers at other sites were attributable to insufficient fruit and non-starchy vegetable consumption.

Implications

Increasing the proportion of Australians who consume the recommended intake of fruit, vegetables and fibre could prevent up to 4% of all cancers.

Diet and cancer risk in the Korean population: a meta- analysis

Many studies have found links between diet and cancer. The summary estimates of the association between dietary factors and cancer risk were investigated using previously reported studies of the Korean population. Gastric cancer risk was inversely associated with the high intake of soy foods [OR (95% CI): 0.32 (0.25-0.40) for soybean, 0.56 (0.45-0.71) for soybean curd, and 0.67 (0.46-0.98) for soymilk], allium vegetables [OR (95% CI): 0.37 (0.26-0.53) for green onion, 0.54 (0.40-0.73) for garlic, and 0.54 (0.35-0.85) for onion], fruits [OR (95% CI): 0.61 (0.42-0.88)], and mushrooms [OR (95% CI): 0.43 (0.21-0.88)]. Salt and Kimchi were associated with an increased gastric cancer risk [OR (95% CI): 1.92 (1.52-2.43) and 2.21 (1.29-3.77), respectively]. Colorectal cancer risk was positively associated with meat intake [OR (95% CI): 1.25 (1.15-1.36)]. Total soy products, soybean curd, and soymilk showed an inverse association with breast cancer risk [OR (95% CI): 0.61 (0.38-0.99), 0.47 (0.34-0.66), and 0.75 (0.57-0.98), respectively]. Green/yellow and light colored vegetables were associated with a reduced risk of breast cancer [OR (95% CI): 0.34 (0.23-0.49) and 0.44 (0.21-0.90), respectively]. Mushroom intake was inversely associated in pre-menopausal women only [OR (95% CI): 0.47 (0.26-0.86)]. In conclusion, soy foods, fruits and vegetables might reduce cancer risk in the Korean population. High salt food might be risk factor for gastric cancer, and intake of high amount of meat might cause colorectal cancer.

Be smart against cancer! A school-based program covering cancer-related risk behavior

Background

Several studies suggest that most school-age children are poorly informed about cancer risk factors. This study examines the effectiveness of the ‘Be smart against cancer’ (BSAC) program in promoting cancer awareness and intentions to engage in health-promoting behavior.

Methods

235 seventh-grade students were randomized to either the intervention (N = 152) or the wait-control group (N = 83). The intervention included the modules: “What is cancer?,” “Sun protection,” “Non smoking,” and “Physical activity, Healthy nutrition, and Limited alcohol consumption.” Outcomes measured at baseline and at the end of the one week BSAC program included knowledge of cancer and its behavioral risk factors, health-promoting intentions, and reported risk behavior.

Results

BSAC was effective in increasing knowledge about cancer and risk factors for cancer (p < .001), as well as in increasing intentions to engage in health-promoting behavior (p < .001), independent of a student’s risk profile. Knowledge did not serve as a mediator for intention building.

Conclusions

The BSAC is an effective school-based program for raising awareness of cancer, associated risk factors and intentions to engage in cancer-preventive behavior. The results indicate that the effectiveness of BSAC is independent of a student’s risk profile. Therefore, it holds considerable promise as a broadly applicable program to raise cancer awareness and promote healthy behavior intentions.

Identifying molecular targets of lifestyle modifications in colon cancer prevention

One in four deaths in the United States is cancer-related, and colorectal cancer (CRC) is the second leading cause of cancer-associated deaths. Screening strategies are utilized but have not reduced disease incidence or mortality. In this regard, there is an interest in cancer preventive strategies focusing on lifestyle intervention, where specific etiologic factors involved in cancer initiation, promotion, and progression could be targeted. For example, exposure to dietary carcinogens, such as nitrosamines and polycyclic aromatic hydrocarbons influences colon carcinogenesis. Furthermore, dietary deficiencies could alter sensitivity to genetic damage and influence carcinogen metabolism contributing to CRC. High alcohol consumption increases the risk of mutations including the fact that acetaldehyde, an ethanol metabolite, is classified as a group 1 carcinogen. Tobacco smoke exposure is also a risk factor for cancer development; approximately 20% of CRCs are associated with smoking. Additionally, obese patients have a higher risk of cancer development, which is further supported by the fact that physical activity decreases CRC risk by 55%. Similarly, chronic inflammatory conditions also increase the risk of CRC development. Moreover, the circadian clock alters digestion and regulates other biochemical, physiological, and behavioral processes that could influence CRC. Taken together, colon carcinogenesis involves a number of etiological factors, and therefore, to create effective preventive strategies, molecular targets need to be identified and beleaguered prior to disease progression. With this in mind, the following is a comprehensive review identifying downstream target proteins of the above lifestyle risk factors, which are modulated during colon carcinogenesis and could be targeted for CRC prevention by novel agents including phytochemicals.

Non-digestible fraction of beans (Phaseolus vulgarisL.) modulates signalling pathway genes at an early stage of colon cancer in Sprague–Dawley rats

Colorectal cancer is one of the most common causes of morbidity and mortality in Western countries, the second cause of cancer mortality in the USA and a major public health problem in Mexico. A diet rich in legumes is directly related to the prevention of colon cancer, showing an inverse relationship with the development of colorectal adenomas in human subjects. The present study shows the results of molecular changes involved in theTp53pathway at an early stage in the distal colon tissue of azoxymethane (AOM)-induced colon cancer in rats evaluated by PCR array after exposure to diets containing the non-digestible fraction (NDF) of cooked bean (cultivar Bayo Madero). Significant differences were detected in seventy-two genes of theTp53-mediated signalling pathway involved in apoptosis, cell-cycle regulation and arrest, inhibition of proliferation and inflammation, and DNA repair.Tp53,Gadd45a,Cdkn1aandBaxwere highly expressed (9·3-, 18·3-, 5·5- and 3·5-fold, respectively) in the NDF+AOM group, whereasCdc25c,Ccne2,E2f1andBcl2were significantly suppressed ( − 9·2-, − 2·6-, − 18·4- and − 3·5-fold, respectively), among other genes, compared with the AOM group, suggesting that chemoprevention of aberrant crypt foci results from a combination of cell-cycle arrest in G1/S and G2/M phases and cell death by apoptotic induction. We demonstrate that the NDF from common bean modulates gene expression profiles in the colon tissue of AOM-induced rats, contributing to the chemoprotective effect of common bean on early-stage colon cancer.

The dietary compounds resveratrol and genistein induce activating transcription factor 3 while suppressing inhibitor of DNA binding/differentiation-1

Various chemopreventive compounds alter gene expression, possibly explaining their biological activity. One gene induced by a variety of chemopreventive compounds is the one coding for the transcription factor activating transcription factor 3 (ATF3). In this study, we performed microarray analysis on mRNA isolated from human colorectal cancer cells overexpressing ATF3 to ascertain the biological activity of this gene in cancer. As a result, 64 genes were induced or repressed. One gene identified by microarray analysis as repressed by overexpression of ATF3 was inhibitor of DNA binding/differentiation-1 (Id1). Id1 is important to cell growth and proliferation and therefore may represent an important downstream target of ATF3 responsible for the biological activity of ATF3. Id1 interacts with ATF3, thereby sequestering its activity, making it an ideal candidate for further study. The induction of ATF3 and repression of Id1 in these cells were confirmed at the mRNA and protein levels by semiquantitative real-time reverse transcription-polymerase chain reaction and western blot analysis, respectively. To determine if the repression of Id1 seen following microarray analysis of these cells occurred following treatment with dietary compounds with known chemotherapeutic activity, human colorectal cancer cells were treated with resveratrol and genistein, and their expression was determined. As a result, ATF3 was induced, and Id1 was repressed, by these compounds and by sulindac sulfide, a positive control, at the mRNA and protein level. Further work is needed to determine the molecular mechanism(s) responsible for the regulation of Id1 and to determine if biological activity of ATF3 overexpression is mediated by repression of Id1 by these compounds.

[Interaction between dietary intake and GSTM1 and GSTT1 polymorphisms in head and neck cancer risk: a case-control study in São Paulo, Brazil]

A hospital-based case-control study was conducted to investigate the potential interaction between dietary factors and polymorphisms in phase II metabolic enzymes GSTM1 and GSTT1, associated with head and neck cancer risk. The study included 103 histologically confirmed incident cases and 101 controls. Food intake was estimated with a validated food frequency questionnaire. The gene polymorphisms were evaluated by PCR. Increased risk was observed in the highest tertile of beef consumption in the presence of the GSTM1 (OR = 10.79; 95%CI: 2.17-53.64) and GSTT1 null alleles (OR = 3.41; 95%CI: 0.43-27.21). Assessment of dietary intake considering the ratio between animal product and vegetable consumption showed OR = 2.35 (95%CI: 0.27-19.85) in the intermediate tertile and OR = 3.36 (95%CI: 0.41-27.03) in the highest tertile. The results suggest a possible interaction between meat intake and GSTM1/GSTT1 polymorphisms in modulating the risk of head and neck cancer, influenced by vegetable consumption.

Behavioral Predictors of Low Fat Intake among Economically Disadvantaged African-American Adolescents

Purpose.

To determine whether five behaviors shown to predict low fat intake in adults predicted low fat intake among economically disadvantaged African-American adolescents.

Design.

Cross-sectional.

Subjects and Measures.

Recruited through youth services agencies serving low-income communities in New York and New Jersey, participants were 265 African-American adolescents aged 10 to 14 years. Participants completed the Block Fat Screener and scales for measuring the following behaviors: avoiding fat as a seasoning, modifying meat to make it lower in fat, substituting high-fat foods with manufactured low-fat equivalents, replacing high-fat foods with fruits and vegetables, and replacing high-fat foods with low-fat foods other than fruits and vegetables.

Analysis.

The reliability and construct validity of the scales were assessed using internal consistency reliability and correlation analyses. Multiple regression analysis was used to determine behavioral predictors of low fat intake.

Results.

Scale coefficient alphas ranged from .60 to .80. Fat avoidance, substitution, and replacement with fruits and vegetables were significantly associated with fat intake. The regression equation containing these behaviors accounted for 12% of the variance in intake. All three behaviors were significant predictors of low fat intake.

Conclusions.

Fewer behaviors have salience for predicting low fat intake among economically disadvantaged African-American adolescents than among adults. Interventions to lower youths' intake should emphasize fat avoidance, substitution, and replacement with fruits and vegetables.

Achievements and future of nutritional cancer epidemiology

We consider some of the earlier work and some recent results on diet and cancer (since the 2007 WCRF/AICR report on Diet and Cancer), discuss challenges facing nutritional cancer epidemiology, and consider the field from the perspective of the need to apply what we know in cancer control. We highlight 2 current difficulties; first, we are uncertain on the stage of carcinogenesis on which many nutritional factors act, second, we often do not know what dose of a nutritional factor is needed to achieve its expected protective effect in humans. Part of the difficulty is the measurement error associated with food frequency questionnaires. Calibration studies (as in the European Prospective Investigation on diet and Cancer) have helped to reduce this, and pooled studies have helped to clarify associations. However, there is too little work on new biomarkers of nutrition; with the new techniques available (especially proteomics, and metabolomics) it should be possible to identify more and better biomarkers that could be used in repeated blood or urine samples and give very good information on diet. In cancer control we need to determine how to reduce the prevalence of obesity and increase physical activity in populations, not whether they are causal factors. This could be achieved by community-based interventions linked to some of the new cohort studies being initiated. We conclude we have reached the stage in nutritional cancer epidemiology where we need to concentrate more on applying the lessons we have learnt, than in seeking new aetiological associations.

The role of integrative oncology in a tertiary prevention survivorship program

OBJECTIVE

Since 64% of cancer patients survive more than 5 years beyond diagnosis, oncologists are challenged to expand their focus from acute care to managing the long-term health consequences of cancer treatment and ensuring the integration of cancer prevention into their practices. This review defines the cancer prevention role of integrative oncology as a key component in survivorship programs.

METHODS

A narrative review consisting of the results of preclinical studies, randomized controlled trials and systematic reviews that may contribute to cancer prevention.

RESULTS

Integrative oncology focuses on the complexities of health and proposes a multitude of approaches. Its categories are mind-body techniques, physical therapies, nutrition plus supplements, and botanicals or natural health products. Behavioral modification, through selected integrative oncology interventions may enhance cancer prevention.

CONCLUSION

Opportunities exist for oncologists to promote lifestyle changes that improve patients' length and quality of life. Integrative oncology utilizes techniques for self-empowerment, individual responsibility, and lifestyle changes that could potentially reduce both cancer recurrence and second primary tumors. Education in the principles of integrative oncology and evidence-based complementary therapies is lacking. There is a need for studies on cost-utility and effectiveness of whole systems programs of integrative oncology for the tertiary prevention of cancer.

Nutrient and fiber intake and risk of renal cell carcinoma

This study examines the association between nutrient and fiber intake and the risk of renal cell carcinoma (RCC). Between 1994 and 1997 in 8 Canadian provinces, mailed questionnaires were completed by 1,138 incident, histologically confirmed cases of RCC and 5,039 population controls. Measurement included information on socioeconomic status, lifestyle habits, and diet. A 69-item food frequency questionnaire provided data on eating habits 2 yr before data collection. Odds ratios (ORs) and 95% confidence intervals were derived through unconditional logistic regression. Intakes of total fat, saturated fat, monounsaturated fat, trans-fat, and cholesterol were associated with the risk of RCC; the ORs for the highest vs. the lowest quartile were 1.67, 1.53 and 1.46, 1.31, and 1.48, respectively. The positive association was apparently stronger in women, overweight or obese, and never smokers. Sucrose was related to the risk of RCC. High fiber intake was inversely associated with RCC risk. No association was found with intake of total protein and polyunsaturated fat, n-3 and n-6 polyunsaturated fatty acids, and total carbohydrates. The results were consistent across strata of sex, tobacco, and BMI. The findings suggest that a diet low in fats and cholesterol and rich in fiber could favorably affect the risk of RCC.

Cured meat, vegetables, and bean-curd foods in relation to childhood acute leukemia risk: a population based case-control study

Background

Consumption of cured/smoked meat and fish leads to the formation of carcinogenic N-nitroso compounds in the acidic stomach. This study investigated whether consumed cured/smoked meat and fish, the major dietary resource for exposure to nitrites and nitrosamines, is associated with childhood acute leukemia.

Methods

A population-based case-control study of Han Chinese between 2 and 20 years old was conducted in southern Taiwan. 145 acute leukemia cases and 370 age- and sex-matched controls were recruited between 1997 and 2005. Dietary data were obtained from a questionnaire. Multiple logistic regression models were used in data analyses.

Results

Consumption of cured/smoked meat and fish more than once a week was associated with an increased risk of acute leukemia (OR = 1.74; 95% CI: 1.15–2.64). Conversely, higher intake of vegetables (OR = 0.55; 95% CI: 0.37–0.83) and bean-curd (OR = 0.55; 95% CI: 0.34–0.89) was associated with a reduced risk. No statistically significant association was observed between leukemia risk and the consumption of pickled vegetables, fruits, and tea.

Conclusion

Dietary exposure to cured/smoked meat and fish may be associated with leukemia risk through their contents of nitrites and nitrosamines among children and adolescents, and intake of vegetables and soy-bean curd may be protective.

Obesity Reduction Black Intervention Trial (ORBIT): design and baseline characteristics

BACKGROUND

Obesity is associated with many chronic diseases, and weight loss can reduce the risk of developing these diseases. Obesity is highly prevalent among Black women, but weight loss treatment for black women has been understudied until recently. The Obesity Reduction black Intervention Trial (ORBIT) is a randomized controlled trial designed to assess the efficacy of a culturally proficient weight loss and weight loss maintenance program for black women. This paper describes the design of the trial, the intervention, and baseline characteristics of the participants.

METHODS

Two hundred thirteen obese black women aged 30-65 years were randomized to the intervention group or a general health control group. The intervention consists of a 6-month weight loss program followed by a 1-year maintenance program. Weight, dietary intake, and energy expenditure are measured at baseline, 6 months, and 18 months.

RESULTS

More than 40% of participants had a baseline body mass index (BMI) >40 kg/m(2) (class III obesity). Intake of fat and saturated fat was higher and consumption of fruit, vegetables, and fiber was lower than currently recommended guidelines. Self-reported moderate to vigorous physical activity was high (median 85 min/day). However, objectively measured physical activity among a subgroup of participants was lower (median 15 min/day).

CONCLUSIONS

Weight loss among obese black women has received inadequate attention in relation to the magnitude of the problem. Factors that contribute to successful weight loss and more importantly, weight loss maintenance need to be identified.

Dietary fat intake among urban, African American adolescents

This study examined commonly consumed high-fat food sources to estimate dietary fat intake among 314 urban, African American adolescents (mean age (SD)=12.57 (.98) years; 66% female; 91% African American non-Hispanic; and 9% African American Hispanic). Youths' fat intake was measured using the Block Fat Screener. Most (77%) participants had diets very high in fat (i.e., 40% to 50% of energy). Mean frequencies of consumption revealed youths' preferences for the following high-fat food items: corn chips, potato chips, popcorn, and crackers; fried chicken; and doughnuts, pastries, cake, and cookies. Total fat intake differed based on youths' age. Urban, African American adolescents can benefit from intervention to lower their fat intake. Programs that target and address the food preferences and eating habits of this population are clearly needed.

Fisetin, a novel dietary flavonoid, causes apoptosis and cell cycle arrest in human prostate cancer LNCaP cells

Novel dietary agents for prevention and therapy of prostate cancer (PCa) are desired. The aim of this study was to determine the effect of fisetin, a tetrahydroxyflavone, on inhibition of cell growth and induction of apoptosis in human PCa cells. Treatment of fisetin (10-60 microM, 48 h) was found to result in a decrease in the viability of LNCaP, CWR22Rupsilon1 and PC-3 cells but had only minimal effects on normal prostate epithelial cells as assessed by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazoliumbromide assay. Treatment of LNCaP cells with fisetin also resulted in G(1)-phase arrest that was associated with a marked decrease in the protein expression of cyclins D1, D2 and E and their activating partner cyclin-dependent kinases 2, 4 and 6 with concomitant induction of WAF1/p21 and KIP1/p27. Fisetin treatment also resulted in induction of apoptosis, poly (ADP-ribose) polymerase (PARP) cleavage, modulation in the expressions of Bcl-2 family proteins, inhibition of phosphatidyl inositol 3-kinase and phosphorylation of Akt at Ser(473) and Thr(308). There was also induction of mitochondrial release of cytochrome c into cytosol, downregulation of X-linked inhibitor of apoptosis protein and upregulation of second mitochondria-derived activator of caspase/direct inhibitor of apoptosis-binding protein with low pI on treatment of cells with fisetin. Treatment of cells with fisetin also resulted in significant activation of caspases-3, -8 and -9. Pretreatment of cells with caspase inhibitor (Z-VAD-FMK) blocked fisetin-induced activation of caspases. These data provide the first evidence that fisetin could be developed as an agent against PCa.

The role of dietary measurement error in investigating the hypothesized link between dietary fat intake and breast cancer--a story with twists and turns

The association between dietary fat and breast cancer is one of the most controversial hypotheses in nutritional epidemiology. In this editorial, the authors review the evidence from animal and human studies, including international correlation, case-control, cohort studies, intervention trials, and studies comparing dietary assessment instruments. The authors emphasize the importance of the role played by measurement error arising from assessing dietary habits using self-reported questionnaires, as it can distort estimated associations, not necessarily towards the absence of an association. They describe the twists and turns of the dietary fat and breast cancer debate that have revolved around this issue.

Diet and vitamin or mineral supplementation and risk of rectal cancer in Canada

The study examines the relation of diet and vitamin or mineral supplementation with risk of rectal cancer. Mailed questionnaires were completed by 1 380 newly diagnosed patients with histologically confirmed rectal cancer and 3 097 population controls between 1994 and 1997 in seven Canadian provinces. Measurement included information on socio-economic status, lifestyle, diet and vitamin or mineral supplementation. We derived odds ratios and 95% confidence intervals through unconditional logistic regression. Total of consumption of vegetables, fruit and whole-grain products did not reduce the risk of rectal cancer. Consumption of cruciferous vegetables was inversely associated with risk of rectal cancer among women only, as did chicken intake among men. The strongest dietary association with increased rectal cancer risk appeared in males with increasing total fat intake and in females with bacon intake. Vitamin and mineral supplementation showed significant inverse associations with rectal cancer in women only. These findings suggest that dietary risk factors for rectal cancer in women may differ from those in men.

Perceived causes of sporadic cryptosporidiosis and their relation to sources of information

BACKGROUND

The importance of a person's perceptions about the causes of their disease has been emphasised by research on various diseases. Several studies have found perception may be linked to protective behaviours.

OBJECTIVE

This study intends to identify the main perceived causes of sporadic cryptosporidiosis, and to analyse some of the factors that may influence respondent's perception. The role of respondents' attributions, the scientific plausibility of perceptions, and the importance of specific information sources are also explored.

DESIGN

Quantitative and qualitative analyses of data from a case-control study.

SETTING

General population in Wales and north west England.

PARTICIPANTS

The study is based on a sample of 411 respondents from Wales and north west of England, whose cryptosporidiosis diagnosis was confirmed by a laboratory.

RESULTS

The results show that the most frequent perceived causes are water (by drinking it or swimming), contagion (mostly from children), and contaminated food. Perceived causes are qualitatively similar to the ones described in scientific literature, but some quantitative differences are evident. Respondents' certainty in relation to the cause of illness is directly related with plausibility. The most frequent information sources used by respondents were test stool results, environmental health officers, and doctors or nurses. Results suggest that information sources may influence the perception of the causes of cryptosporidiosis. Qualitative data provided a few clues about situations where sporadic and outbreak cases may be confused.

CONCLUSION

In contrast with outbreaks, various information sources in addition to the media are used by people with sporadic cryptosporidiosis that in turn affects the perception of aetiology. This has implications for the dissemination of information about control measures for cryptosporidiosis and surveillance activities.

Dietary Fat and Postmenopausal Invasive Breast Cancer in the National Institutes of Health-AARP Diet and Health Study Cohort

BACKGROUND

Although ecologic association and animal studies support a direct effect of dietary fat on the development of breast cancer, results of epidemiologic studies have been inconclusive.

METHODS

We prospectively analyzed the association between fat consumption and the incidence of postmenopausal invasive breast cancer in the National Institutes of Health-AARP Diet and Health Study, a US cohort comprising 188,736 postmenopausal women who completed a 124-item food-frequency questionnaire in 1995-1996. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated using Cox proportional hazards regression models with adjustment for energy and potential confounding factors. All statistical tests were two-sided.

RESULTS

Over an average follow-up of 4.4 years, the cohort yielded 3501 cases of invasive breast cancer. The hazard ratio of breast cancer for the highest (median intake, 40.1% energy from total fat; 434 cases per 100,000 person-years) versus the lowest (median intake, 20.3% energy from total fat; 392 cases per 100,000 person-years) quintile of total fat intake was 1.11 (95% CI = 1.00 to 1.24; P(trend) = .017). The corresponding hazard ratio for a twofold increase in percent energy from total fat on the continuous scale was 1.15 (95% CI = 1.05 to 1.26). Positive associations were also found for subtypes of fat (hazard ratio for a twofold increase in percent energy from saturated fat = 1.13; 95% CI = 1.05 to 1.22; from monounsaturated fat, HR = 1.12; 95% CI = 1.03 to 1.21; from polyunsaturated fat, HR = 1.10, 95% CI = 1.01 to 1.20). Correction for measurement error in nutrient intakes, on the basis of a calibration substudy that used two 24-hour dietary recalls, strengthened the associations, yielding an estimated hazard ratio for total fat of 1.32 (95% CI = 1.11 to 1.58). Secondary analyses showed that associations between total, saturated, and monounsaturated fat intakes were confined to women who were not using menopausal hormone therapy at baseline.

CONCLUSION

In this large prospective cohort with a wide range of fat intake, dietary fat intake was directly associated with the risk of postmenopausal invasive breast cancer.

Who remembers whether they had asthma as children?

PURPOSE

To assess misclassification in adults reporting childhood asthma.

METHODS

The Tasmanian Asthma Survey commenced in 1968 when 8,583 7-year-old children attending school in Tasmania (participants) were studied. In 1991-1993, a stratified sample of 1,494 participants was studied. Their recall of childhood asthma was compared to their parents' prospectively gathered report.

RESULTS

Where participants had childhood asthma, those with current asthma, severe eczema, or hay fever were less likely to misclassify while females were more likely to misclassify. Where participants had no childhood asthma, misclassification was associated with current asthma, hay fever, or allergies.

CONCLUSIONS

Retrospective self-assessment of childhood asthma is unreliable.

Methyl deficiency, alterations in global histone modifications, and carcinogenesis

The methyl-deficient model of endogenous hepatocarcinogenesis in rodents is unique in that dietary omission rather than the addition of chemical carcinogens leads to tumor formation. Thus, the biochemical and molecular events predisposing to cancer in this model result from chronic metabolic stress and provide an ideal model system to study progressive alterations that occur during carcinogenesis. Moreover, epigenetic alterations imposed by this diet are believed to be 1 of the main mechanisms responsible for malignant transformation of rat liver cells. In this study we examined the changes in global histone modification patterns in liver during hepatocarcinogenesis induced by methyl deficiency. Feeding animals the methyl-deficient diet (MDD) led to progressive loss of histone H4 lysine 20 trimethylation (H4K20me3), H3 lysine 9 trimethylation (H3K9me3), and histone H3 lysine 9 (H3K9ac) and histone H4 lysine 16 (H4K16ac) acetylation. A considerable decrease of H4K20me3 and H3K9ac was also detected in liver tumors induced by MDD. In contrast, liver tumors displayed an increase in H3K9me3 and H4K16ac. To determine the possible mechanism of alterations of histone modifications, we analyzed the expression of histone-modifying enzymes in liver during hepatocarcinogenesis. The expression of Suv4-20h2 and RIZ1 histone methyltransferases (HMTs) steadily decreased along with the development of liver tumors and reached its lowest level in tumor tissue, whereas the expression of Suv39-h1 HMT and histone acetyltransferase 1 (HAT1) substantially increased in tumors. These results illustrate the complexity and importance of histone modification changes in the etiology of hepatocarcinogenesis induced by MDD.

Opportunities and challenges in the prevention and control of cancer and other chronic diseases: children's diet and nutrition and weight and physical activity

OBJECTIVE

The purpose of this article is to review the role of behavioral research in disease prevention and control, with a particular emphasis on lifestyle- and behavior-related cancer and chronic disease risk factors--specifically, relationships among diet and nutrition and weight and physical activity with adult cancer, and tracking developmental origins of these health-promoting and health-compromising behaviors from childhood into adulthood.

METHOD

After reviewing the background of the field of cancer prevention and control and establishing plausibility for the role of child health behavior in adult cancer risk, studies selected from the pediatric published literature are reviewed. Articles were retrieved, selected, and summarized to illustrate that results from separate but related fields of study are combinable to yield insights into the prevention and control of cancer and other chronic diseases in adulthood through the conduct of nonintervention and intervention research with children in clinical, public health, and other contexts.

RESULTS

As illustrated by the evidence presented in this review, there are numerous reasons (biological, psychological, and social), opportunities (school and community, health care, and family settings), and approaches (nonintervention and intervention) to understand and impact behavior change in children's diet and nutrition and weight and physical activity.

CONCLUSIONS

Further development and evaluation of behavioral science intervention protocols conducted with children are necessary to understand the efficacy of these approaches and their public health impact on proximal and distal cancer, cancer-related, and chronic disease outcomes before diffusion. It is clear that more attention should be paid to early life and early developmental phases in cancer prevention.

Positive selection in the evolution of cancer

We hypothesize that forms of antagonistic coevolution have forged strong links between positive selection at the molecular level and increased cancer risk. By this hypothesis, evolutionary conflict between males and females, mothers and foetuses, hosts and parasites, and other parties with divergent fitness interests has led to rapid evolution of genetic systems involved in control over fertilization and cellular resources. The genes involved in such systems promote cancer risk as a secondary effect of their roles in antagonistic coevolution, which generates evolutionary disequilibrium and maladaptation. Evidence from two sources: (1) studies on specific genes, including SPANX cancer/testis antigen genes, several Y-linked genes, the pem homebox gene, centromeric histone genes, the breast cancer gene BRCA1, the angiogenesis gene ANG, cadherin genes, cytochrome P450 genes, and viral oncogenes; and (2) large-scale database studies of selection on different functional categories of genes, supports our hypothesis. These results have important implications for understanding the evolutionary underpinnings of cancer and the dynamics of antagonistically-coevolving molecular systems.

Fruit and vegetable consumption and colorectal adenomas in the Nurses' Health Study

Consumption of fruits and vegetables may confer protection from colorectal adenomas, but the limited observational and interventional evidence is inconclusive. We examined the association between fruit and vegetable consumption and the prevalence and incidence of adenomas of the distal colon and rectum in the Nurses' Health Study (NHS). We used data from 34,467 women in the NHS who had undergone colonoscopy or sigmoidoscopy during follow-up between 1980 and 1998. Consumption of fruits and vegetables was assessed in 1980, 1984, 1986, 1990, and 1994 using a semiquantitative food frequency questionnaire; 1,720 prevalent cases of adenoma of the distal colon and rectum were diagnosed between 1980 and 1998. Frequent consumption of fruit was inversely related to the risk of being diagnosed with polyps, whereas little association was found for vegetable consumption. Women who reported consuming five or more servings of fruit a day had an odds ratio (OR) of 0.60 [95% confidence interval (95% CI), 0.44-0.81] for developing colorectal adenomas compared with women who consumed only one or fewer servings of fruit per day, after adjustment for relevant covariates (P(trend) = 0.001). The respective OR for vegetable consumption was 0.82 (95% CI, 0.65-1.05; P(trend) = 0.1). Women who consumed four or more servings of legumes per week had a lower incidence of colorectal adenomas than women who reported consuming one serving per week or less (OR, 0.67; 95% CI, 0.51-0.90; P(trend) = 0.005). Frequent consumption of fruit may reduce the risk of colorectal adenomas.

Evolutionary biology of cancer

Cancer is driven by the somatic evolution of cell lineages that have escaped controls on replication and by the population-level evolution of genes that influence cancer risk. We describe here how recent evolutionary ecological studies have elucidated the roles of predation by the immune system and competition among normal and cancerous cells in the somatic evolution of cancer. Recent analyses of the evolution of cancer at the population level show how rapid changes in human environments have augmented cancer risk, how strong selection has frequently led to increased cancer risk as a byproduct, and how anticancer selection has led to tumor-suppression systems, tissue designs that slow somatic evolution, constraints on morphological evolution and even senescence itself. We discuss how applications of the tools of ecology and evolutionary biology are poised to revolutionize our understanding and treatment of this disease.