Diet, physical activity, and colorectal cancer among Chinese in North America and China

Exercise and colorectal cancer: prevention and molecular mechanisms

Exercise and physical activity have been shown to be strongly associated with a decreased incidence rate of various chronic diseases especially numerous human malignancies. A huge number of clinical trials and meta-analysis have demonstrated that exercise is significantly effective in lowering the risk of colorectal cancer. In addition, it is suggested as an effective therapeutic modality against this cancer type. Therefore, in this review, we will review comprehensibly the effects of exercise in preventing, treating, and alleviating the adverse effects of conventional therapeutic options in colorectal cancer. Moreover, the possible mechanisms underlying the positive effects of exercise and physical activity in colorectal cancer, including regulation of inflammation, apoptosis, growth factor axis, immunity, epigenetic, etc. will be also discussed.

Exercise is an effective post-treatment management program in colorectal cancer survivals

Exercise improves muscle strength, cardiorespiratory fitness, emotional distress, physical activity, fatigue, and sleep quality in colorectal patients undergoing chemotherapy

Targeting and modulating insulin-like growth factor (IGF) system, inflammation, apoptosis, immunity, epigenetic, Leptin and Ghrelin, and signaling pathways are major underlying mechanisms for preventive effects of exercise in colorectal cancer

Dietary Characteristics and Influencing Factors on Chinese Immigrants in Canada and the United States: A Scoping Review

Background: Chinese immigrants are an integral part of Canadian and American society. Chinese immigrants believe diet to be an important aspect of health, and dietary behaviours in this population have been associated with changes in disease risk factors and disease incidence. This review aims to summarize the characteristics of the dietary behaviours of Chinese immigrants and the associated influencing factors to better inform individual, clinical, and policy decisions. Methods: This scoping review was written in accordance with PRISMA guidelines. MEDLINE, PsychINFO, CINAHL, AgeLine, ERIC, ProQuest, Nursing and Allied Health Database, PsychARTICLES, and Sociology Database were utilized for the literature search. Articles were included if they explored dietary or nutritional intake or its influencing factors for Chinese immigrants to Canada or the United States. Results: A total of 51 papers were included in this review. Among Chinese immigrants in Canada and the United States, the intake of fruits and vegetables, milk and alternatives, and fiber were inadequate against national recommendations. Chinese immigrants showed increased total consumption of food across all food groups and adoption of Western food items. Total caloric intake, meat and alternatives intake, and carbohydrate intake increased with acculturation. Individual factors (demographics, individual preferences, and nutritional awareness), familial factors (familial preferences and values, having young children in the family, and household food environment), and community factors (accessibility and cultural conceptualizations of health and eating) influenced dietary behaviours of Chinese immigrants. Discussion and Conclusion: Efforts should be undertaken to increase fruit, vegetable, and fibre consumption in this population. As dietary acculturation is inevitable, efforts must also be undertaken to ensure that healthy Western foods are adopted. It is important for healthcare providers to remain culturally sensitive when providing dietary recommendations. This can be achieved through encouragement of healthy ethnocultural foods and acknowledgement and incorporation of traditional health beliefs and values into Western evidence-based principles where possible.

Association of sedentary work with colon and rectal cancer: systematic review and meta-analysis

OBJECTIVES

There has been no research on sedentary behaviour in the occupational domain that occupies a large portion of the daily life.

METHODS

We conducted a meta-analysis to investigate the association between sedentary work and colorectal cancer. We searched PubMed, Embase and Cochrane databases up to 12 August 2020 for peer-reviewed journal articles that assessed the association between sedentary work and colon or rectal cancer. Pooled estimates of ORs were obtained using random effects models. Statistical tests for publication bias, heterogeneity and sensitivity analysis were applied.

RESULTS

Of the 5 381 studies initially identified, 23 studies with 64 reports were eligible for inclusion. Sedentary work significantly increased the risk of colon cancer (pooled OR=1.21, 95% CI 1.11 to 1.31, p value ≤0.0001) and rectal cancer (pooled OR=1.08, 95% CI 1.00 to 1.16, p value=0.0395). The adjustment for leisure time physical activity attenuated the association and made the risk estimates non-significant for sedentary behaviour, but the association was independent of sex, control of body mass index and assessment of sedentary behaviour.

CONCLUSIONS

We found evidence of association between sedentary work and the risk of colon or rectal cancer. Limiting excessive sedentary work could be an important means of preventing colon and rectal cancer.

A clinical study of newly-diagnosed colorectal cancer over 2 years in a gastroenterology center in Iraq

Background and study aims Colorectal cancer (CRC) is the most common gastrointestinal cancer and the third most commonly diagnosed malignancy affecting about one million individuals each year. The etiology for most cases of CRC appears to be related to environmental factors. This study to describe the main characteristics of this malignancy regarding age, gender, and anatomical sub site distribution, as well as the main presenting symptoms in Iraqi patients.

Patients and methods Patients with newly-diagnosed CRC by colonoscopy findings and confirmed by histopathological examination of endoscopic colonic biopsies were studied.

Results Sixty three cases with a newly-diagnosed CRC were included in this study. There were 31 (49.2%) males and 32 (50.8%) females. CRC peaked in the 60–69 years old age group (p < 0.05), more than 60% were between 40 and 69 years old. Fresh bleeding per rectum was the most common symptom occurred in 48 (76.2%) patients; while the least common was weight loss (19%). The mean duration of symptoms before referral was 7.3 ± 12.6 months. The tumor sites of the CRC were the rectum and sigmoid region seen in 77.8% (p < 0.05), the rectum alone reported in 37 patients (58.7%); followed by sigmoid colon in 12 (19%) patients, cecum in 7 (11.1%) patients and the ascending colon seen in 2 (3.2%) patients.

Conclusions In this study CRC occurs in relatively younger age groups in comparison to studies in the developed countries with rectal cancer predominates of all colorectal cancers.

Evodiamine inhibits high-fat diet-induced colitis-associated cancer in mice through regulating the gut microbiota

OBJECTIVE

High-fat diet is one of the main risk factors that disrupt the balance of gut microbiota, which eventually will induce colorectal cancer (CRC). Evodiamine (EVO) is a wildly used multifunctional traditional Chinese medicine extract. In this study, we investigated the role of gut microbiota in high-fat diet-propelled CRC and the potential of EVO for CRC chemoprevention.

METHODS

Gut microbiota, serum d-lactic acid and endotoxin from 38 patients with colon cancer and 18 healthy subjects were detected by quantitative real-time polymerase chain reaction and enzyme-linked immunosorbent assay (ELISA). In addition, body mass index, phospho-signal transducer and activator of transcription 3 (p-STAT3) expression in cancer tissues and paracancerous tissues were detected by immunohistochemistry. A mouse intestinal inflammatory tumor model was established by azomethane/sodium dextran sulfate, followed by treatment with EVO and 5-aminosalicylic acid (ASA). Gut microbiota and inflammatory factors were detected by quantitative polymerase chain reaction, while serum d-lactic acid and endotoxin were detected by ELISA. Furthermore, cell proliferation, cell apoptosis, and interleukin (IL)-6/STAT3/P65 pathway were evaluated by 5-ethynyl-2'-deoxyuridine, terminal-deoxynucleotidyl transferase-mediated nick-end labeling, and Western blot assays.

RESULTS

In patients with colon cancer, the numbers of Enterococcus faecalis and Escherichia coli were increased, while those of Bifidobacterium, Campylobacter and Lactobacillus were decreased. Serum endotoxin and d-lactic acid levels and p-STAT3 levels were significantly increased. In the mouse model, both EVO and ASA inhibited tumor formation, decreased the proliferation of tumor cells, and induced apoptosis of tumor cells. Compared with the control group, the numbers of E. faecalis and E. coli were decreased, while Bifidobacterium, Campylobacter and Lactobacillus numbers were increased. In the EVO group, serum endotoxin and d-lactic acid levels and inflammatory factors were significantly decreased. Further, the IL6/STAT3/P65 signaling pathway was inhibited in the EVO group.

CONCLUSION

EVO may inhibit the occurrence of colon cancer by regulating gut microbiota and inhibiting intestinal inflammation. The potential mechanism involves inhibition of the IL6/STAT3/P65 signaling pathway, revealing its potential therapeutic significance in clinical applications.

Development, validation and utilisation of dish-based dietary assessment tools: a scoping review

Objective:

To summarise the existing evidence of development, validation and current status of utilisation of dish-based dietary assessment tools.

Design:

Scoping review.

Setting:

Systematic search using PubMed and Web of Science.

Results:

We identified twelve tools from seventy-four eligible publications. They were developed for Koreans (n 4), Bangladeshis (n 2), Iranians (n 1), Indians/Malays/Chinese (n 1), Japanese (n 3) and Chinese Americans (n 1). Most tools (10/12) were composed of a dish-based FFQ. Although the development process of a dish list varied among the tools, six studies classified mixed dishes based on the similarity of their characteristics such as food ingredients and cooking methods. Tools were validated against self-reported dietary information (n 9) and concentration biomarkers (n 1). In the eight studies assessing the differences between the tool and a reference, the mean (or median) intake of energy significantly differed in five studies, and 26–83 % of nutrients significantly differed in eight studies. Correlation coefficients for energy ranged from 0·15 to 0·87 across the thirteen studies, and the median correlation coefficients for nutrients ranged from 0·12 to 0·77. Dish-based dietary assessment tools were used in fifty-nine studies mainly to assess diet–disease relationships in target populations.

Conclusions:

Dish-based dietary assessment tools have exclusively been developed and used for Asian-origin populations. Further validation studies, particularly biomarker-based studies, are needed to assess the applicability of tools.

Occupational sitting time and subsequent risk of cancer: The Japan Public Health Center-based Prospective Study

Although occupational sitting time has been associated with adverse health outcomes and mortality, the association with cancer incidence remains unknown. This study investigated the association between occupational sitting time and risk of total and site‐specific cancer in a Japanese population. We evaluated 33 307 participants aged 50‐79 years who responded to a questionnaire in 2000‐2003 in the Japan Public Health Center‐based Prospective Study and were followed until 2013. Participants were grouped by sitting time at work. Hazard ratio (HR) and 95% confidence interval (CI) of cancer incidence were calculated with adjustment for potential confounders including moderate‐to‐vigorous physical activity. During 10.2 years of follow‐up, 3807 newly diagnosed cases of cancer were identified. Occupational sitting time was marginally associated with total cancer, with multivariable HRs for the ≥7 h/d vs 1 to <3 h/d category of 1.12 (95% CI, 0.99‐1.26; P for trend = .071) in men, but not women. Among findings for cancers at specific sites, long occupational sitting time was associated with increased risk of pancreas cancer, with multivariable HRs for the ≥7 h/d vs 1 to <3 h/d category of 2.25 (95% CI, 1.17‐4.34; P for trend = .021) in men, and lung cancer, with multivariable HRs for the ≥7 h/d vs 1 to <3 h/d category of 2.80 (95% CI, 1.33‐5.90; P for trend = .013) in women. Extended sitting time at work was associated with an increased risk of pancreas cancer in men and lung cancer in women.

Role of intestinal microbiome in American ginseng-mediated colon cancer prevention in high fat diet-fed AOM/DSS mice [corrected]

OBJECTIVE

Chronic intestinal inflammation is a risk factor for colorectal cancer (CRC) initiation and development. Diets that are rich in Western style fats have been shown to promote CRC. This study was conducted to investigate the role of intestinal microbiome in American ginseng-mediated CRC chemoprevention in a mouse model. The population and diversity of enteric microbiome were evaluated after the ginseng treatment.

METHODS

Using an azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced gut inflammation and tumorigenesis mouse model, the effects of oral American ginseng on high fat diet-associated enteric pathology were determined. After establishment of a 16S rRNA illumina library from fecal samples, MiSeq sequencing was carried out to reveal the microbial population. The alpha and beta diversities of microbiome were analyzed.

RESULTS

American ginseng significantly attenuated AOM/DSS-induced colon inflammation and tumorigenesis by reducing the colitis score and colon tumor multiplicity. The MiSeq results showed that the majority of sequences fell into three phyla: Firmicutes, Bacteroidetes and Verrucomicrobia. Further, two significant abundance shifts at the family level, Bacteroidaceae and Porphyromonadaceae, were identified to support ginseng's anti-colitis and anti-tumor effects. In addition, alpha and beta diversity data demonstrated that ginseng led to a profound recovery from the AOM/DSS-induced dysbiosis in the microbial community.

CONCLUSION

Our results suggest that the CRC chemopreventive effects of American ginseng are mediated through enteric microbiome population-shift recovery and dysbiosis restoration. Ginseng's regulation of the microbiome balance contributes to the maintenance of enteric homeostasis.

Daily sedentary time and its association with risk for colorectal cancer in adults: A dose-response meta-analysis of prospective cohort studies

Sedentary behavior is emerging as an independent risk factor for health. However, previous studies have indicated that sedentary behaviors are associated with the colorectal cancer risk, but presented controversial results.Studies in PubMed and EMBASE were searched update to February 2017 to identify and quantify the potential dose-response association between daily sedentary time and colorectal cancer.Twenty-eight eligible studies involving a total of 47,84,339 participants with 46,071 incident cases were included in this meta-analysis. Our results showed statistically significant association between prolong television viewing time and colorectal cancer (odds ratio [OR] 1.17, 95% confidence interval [CI] 1.09-1.24, P < .001). Additionally, we obtained the best fit at an inflection point of 2 hours per day in piecewise regression analysis, the summary relative risk (RR) of colorectal cancer for an increase of 2 hours per day television viewing was 1.07 (95% CI 1.05-1.10, P < .001). Furthermore, prolong occupational sitting time was correlated with a significantly higher risk of colorectal cancer (OR 1.15, 95% CI 1.08-1.22, P < .001), increasing 2 hours per day of occupational sitting time per day was associated with a 4% incremental in the risk of colorectal cancer (RR 1.04, 95% CI 1.01-1.08). Additionally, prolong total sitting time was associated with a significantly higher risk of colorectal cancer (OR 1.06, 95% CI 1.03-1.09, P < .001). Increasing 2 hours of total sitting time per day was associated with a 2% incremental in the risk of colorectal cancer (RR 1.02, 95% CI 1.01-1.06). Subgroup meta-analyses in study design, study quality, number of participants, and number of cases showed consistent with the primary findings.Prolonged television viewing, occupational sitting time, and total sitting time are associated with increased risks of colorectal cancer.

Association between dietary fat intake and colorectal adenoma in korean adults: A cross-sectional study

The incidence of colorectal cancer is rapidly increasing in South Korea. It is important to clarify the association between colorectal cancer and diet, being one of the main modifiable risk factors, as such studies in the Korean population are lacking.A cross-sectional study was performed using data from participants who had undergone a screening colonoscopy and a nutritional assessment during a routine health check-up from January 2008 to December 2011. Dietary intake data were derived from 1-day food records; colorectal adenoma was histopathologically confirmed by biopsy during colonoscopy. Eventually, 2604 participants were included in the analysis. The risk of colorectal adenoma by quintile of dietary fat intake was analyzed using logistic regression. Subgroup analyses by degree of risk and by location of colorectal adenoma were additionally performed.In men, total fat intake was not associated with risk of colorectal adenoma. However, risk of colorectal adenoma increased with higher saturated fatty acid (SFA) intake. The adjusted odds ratio in the highest quintile was 1.71 (95% confidence interval, 1.01-2.91) compared with that in the lowest quintile. There was no significant association between fat intake and risk of colorectal adenoma characterized by subsite. In female participants, total fat and specific fatty acid intake were not associated with risk of colorectal adenoma.These data support that high SFA intake is associated with risk of colorectal adenoma in Korean men.

Dietary sources of calcium among parents and their early adolescent children in the United States by parent race/ethnicity and place of birth

Dietary calcium sources may differ by race/ethnicity and dietary acculturation. A cross-sectional, convenience sample including 587 United States (US) Asian, Hispanic and non-Hispanic White parent-child (10-13 years) pairs completed a calcium food frequency questionnaire. Calcium sources were ranked by mean percent contribution to total adjusted calcium intake, and compared by ethnic group and parents' location of birth. Five foods (fluid milk, cheese, milk on cereal, yogurt, and lattes) represented 49% of total calcium intake for parents. The same foods (except lattes) represented 55% of total calcium for early adolescent children. Fluid milk provided the largest mean percentage of intake for all race/ethnic groups among parents and children. Several food sources of calcium were greater for foreign-born versus US-born Asian or Hispanic parents and children. Understanding calcium food sources and changes in dietary patterns that affect calcium intake among parents and children is important to better promote adequate intake.

The association between comorbidities and the quality of life among colorectal cancer survivors in the People's Republic of China

BACKGROUND

Cancer survivors with certain comorbidities had lower quality of life (QOL). This study was performed to investigate the prevalence of comorbidities and the association between comorbidities and the QOL among Chinese colorectal cancer survivors (CCS).

METHODS

A cross-sectional study was conducted among 1,398 CCS between April and July 2013 in Shanghai, People's Republic of China. All the participants were asked to complete a simplified Chinese version of the European Organization for Research and Treatment quality of life version 3 questionnaire and questions on sociodemographic characteristics and comorbidities. In order to mitigate the bias caused by confounding factors, multiple linear regression models were employed to calculate the adjusted means of QOL scores.

RESULTS

The proportion of participants without any comorbidity was only 20.2%. The CCS with comorbidities except hypertension scored significantly lower on the European Organization for Research and Treatment quality of life version 3 questionnaire global health and functioning scales and Functional Assessment of Cancer Therapy-General scales but higher on the European Organization for Research and Treatment quality of life version 3 questionnaire symptom scores, indicating that they had poorer QOL, particularly for cardiovascular, respiratory, digestive, and musculoskeletal diseases.

CONCLUSION

There exists a significant association between comorbidities and QOL among Chinese CCS, and participants with comorbidities generally reported lower QOL scores. These findings suggested comprehensive care for CCS.

Hospital outpatients are satisfactory for case-control studies on cancer and diet in China: a comparison of population versus hospital controls

BACKGROUND

To investigate the internal validity of a food-frequency questionnaire (FFQ) developed for use in Chinese women and to compare habitual dietary intakes between population and hospital controls measured by the FFQ.

MATERIALS AND METHODS

A quantitative FFQ and a short food habit questionnaire (SFHQ) were developed and adapted for cancer and nutritional studies. Habitual dietary intakes were assessed in 814 Chinese women aged 18-81 years (407 outpatients and 407 population controls) by face-to-face interview using the FFQ in Shenyang, Northeast China in 2009-2010. The Goldberg formula (ratio of energy intake to basal metabolic rate, EI/BMR) was used to assess the validity of the FFQ. Correlation analyses compared the SFHQ variables with those of the quantitative FFQ. Differences in dietary intakes between hospital and population controls were investigated. Odds ratios (ORs) and 95% confidence intervals (CIs) were obtained using conditional logistic regression analyses.

RESULTS

The partial correlation coefficients were moderate to high (0.42 to 0.80; all p<0.05) for preserved food intake, fat consumption and tea drinking variables between the SFHQ and the FFQ. The average EI/BMR was 1.93 with 88.5% of subjects exceeding the Goldberg cut-off value of 1.35. Hospital controls were comparable to population controls in consumption of 17 measured food groups and mean daily intakes of energy and selected nutrients.

CONCLUSIONS

The FFQ had reasonable validity to measure habitual dietary intakes of Chinese women. Hospital outpatients provide a satisfactory control group for food consumption and intakes of energy and nutrients measured by the FFQ in a Chinese hospital setting.

Foreign- vs US-born Asians and the association of type I uterine cancer

OBJECTIVE

The purpose of this study was to determine the association of type I endometrioid uterine cancer in US-born vs immigrant Asian women.

STUDY DESIGN

Data were obtained from the Surveillance, Epidemiology, and End Results Program from 2001-2009. Chi-squared, Kaplan-Meier, and binomial logistic regression analyses were used for statistics.

RESULTS

Of 4834 Asian women with uterine cancer, 62% were US-born and 38% were immigrants. Of these women, 2972 (61%) had type I (grade 1 or 2, endometrioid histologic type) uterine cancer. Compared with patients with type II disease (grade 3, clear cell and serous histologic type), patients with type I disease were younger (age 55 vs 59 years; P < .01) and had lower stage disease (90% vs 71%; P < .01). US-born Asian women had a significantly higher proportion of type I uterine cancers in contrast to their immigrant counterparts (65% vs 56%; P < .01). Of all immigrants, the proportion of type I cancers was lowest in Japanese women followed by Chinese and Filipino women, respectively (48% vs 52% vs 58%; P < .01). The 5-year disease-specific survivals of US-born vs immigrant Asian women with type I cancer was 92% for both groups. Over 3 time periods (2001-2003, 2004-2006, and 2007-2009), there was an increase in type I cancers among US-born Asian women (61% to 65% to 68%; P < .01).

CONCLUSION

US-born Asian women are more likely to be diagnosed with type I uterine cancer compared with immigrants. Over the study period, there was a trend towards an increase in type I cancers among US-born Asian women.

Physical inactivity, water intake and constipation as risk factors for colorectal cancer among adults in Jordan

BACKGROUND

Physical activity has been found to play a role in cancer prevention. The purpose of this matched case-control study was to investigate the association between physical activity levels, water intake, constipation and colorectal cancer (CRC).

MATERIALS AND METHODS

Two hundred and thirty-two patients diagnosed with CRC (125 male, 107 female) were enrolled in this case-control study. Cases were matched to 271 population controls (137 male, 134 female).

RESULTS

Drinking more than 4 cups of water daily decreased the risk of CRC by 33-42%; however, this effect was non-significant. Having constipation was found to be a significant risk factor for developing CRC with an OR=6.284 (95%CI=2.741-14.40). With reference to sedentary behavior, minimum activity (600-3000 Metabolic Equivalents Task (MET)) had 43% protection against CRC and the level of Health Enhancing Physical Activity OR was 0.58 (at 95%CI; 0.37-0.92). A significant negative association was found between CRC and physical activity levels expressed as both METs and MET-hours/week (p for trend=0.017 and 0.03, respectively). Among females, a significant trend of reduction in CRC by 62% was observed with increasing the level of physical activity expressed in MET (p for trend=0.04).

CONCLUSIONS

The risk of CRC may be reduced by adopting a healthy lifestyle and practicing physically activity regularly, especially among females. Consuming adequate amounts of water and healthy bowel motility could also reduce the risk of CRC.

Cytoreductive surgery plus hyperthermic intraperitoneal chemotherapy improves survival for patients with peritoneal carcinomatosis from colorectal cancer: a phase II study from a Chinese center

Background

Peritoneal carcinomatosis (PC) is a difficult clinical challenge in colorectal cancer (CRC) because conventional treatment modalities could not produce significant survival benefit, which highlights the acute need for new treatment strategies. Our previous case-control study demonstrated the potential survival advantage of cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) over CRS alone. This phase II study was to further investigate the efficacy and adverse events of CRS+HIPEC for Chinese patients with CRC PC.

Methods

A total of 60 consecutive CRC PC patients underwent 63 procedures consisting of CRS+HIPEC and postoperative chemotherapy, all by a designated team focusing on this combined treatment modality. All the clinico-pathological information was systematically integrated into a prospective database. The primary end point was disease-specific overall survival (OS), and the secondary end points were perioperative safety profiles.

Results

By the most recent database update, the median follow-up was 29.9 (range 3.5–108.9) months. The peritoneal cancer index (PCI) ≤20 was in 47.0% of patients, complete cytoreductive surgery (CC0-1) was performed in 53.0% of patients. The median OS was 16.0 (95% confidence interval [CI] 12.2–19.8) months, and the 1-, 2-, 3-, and 5-year survival rates were 70.5%, 34.2%, 22.0% and 22.0%, respectively. Mortality and grades 3 to 5 morbidity rates in postoperative 30 days were 0.0% and 30.2%, respectively. Univariate analysis identified 3 parameters with significant effects on OS: PCI ≤20, CC0-1 and adjuvant chemotherapy over 6 cycles. On multivariate analysis, however, only CC0-1 and adjuvant chemotherapy ≥6 cycles were found to be independent factors for OS benefit.

Discussion

CRS+HIPEC at a specialized treatment center could improve OS for selected CRC PC patients from China, with acceptable perioperative safety.

Observations on the epidemiology of gastrointestinal and liver cancers in the Asia-Pacific region

Gastric cancer (GC) has long been thought to be an Asian type of cancer that is broadly associated with poverty, whereas colorectal cancer (CRC) has been thought to be a Western type of cancer associated with affluence. The incidence of GC has declined dramatically in the West but has a very high incidence in East Asia. The age-standardized incidence rates (ASR) have also declined. The decrease in the incidence of GC is associated with the decrease in the prevalence of Helicobacter pylori (H. pylori) infection worldwide. The discrepancy between a high H. pylori infection rate and a low GC incidence is seen chiefly among southern Asians of Indian origin and has been aptly termed the "Indian enigma". CRC is a new emerging cancer in this region. Some of the highest CRC ASR have been reported from Asian countries, in many of which it has now surpassed that of GC. Liver cancer is also an important cancer in the Asia-Pacific region. The highest ASR worldwide is reported from the Asian countries of Mongolia, Korea and Japan. The predominant underlying etiology across the region has been hepatitis B virus infection, except in Japan, where hepatitis C is an important cause of hepatocellular carcinoma (HCC). With mass vaccination of hepatitis B at birth and improved public health measures in many countries, hepatitis B and C are set to decline with time. However, the exponential increase in obesity and consequent non-alcoholic fatty liver disease portends a future epidemic of fatty liver-related HCC.

Burgers or tofu? Eating between two worlds: risk information seeking and processing during dietary acculturation

This study attempted to examine what factors might motivate Chinese international students, the fastest growing ethnic student group in the United States, to seek and process information about potential health risks from eating American-style food. This goal was accomplished by applying the Risk Information Seeking and Processing (RISP) model to this study. An online 2 (severity: high vs. low) × 2 (coping strategies: present vs. absent) between-subjects experiment was conducted via Qualtrics to evaluate the effects of the manipulated variables on the dependent variables of interest as well as various relationships proposed in the RISP model. A convenience sample of 635 participants was recruited online. Data were analyzed primarily using structural equation modeling (SEM) in AMOS 21.0 with maximum likelihood estimation. The final conceptual model has a good model fit to the data given the sample size. The results showed that although the experimentally manipulated variables failed to cause any significant differences in individuals' perceived severity and self-efficacy, this study largely supported the RISP model's propositions about the sociopsychological factors that explain individual variations in information seeking and processing. More specifically, the findings indicated a prominent role of informational subjective norms and affective responses (both negative and positive emotions) in predicting individuals' information seeking and processing. Future implications and limitations are also discussed.

Nativity, duration of residence and chronic health conditions in Australia: do trends converge towards the native-born population?

Using data from waves 3, 7 and 9 of the Household, Income and Labour Dynamics in Australia (HILDA) survey, a group-mean-centred multilevel mixed model and self-reported chronic conditions, this study contributes to the limited longitudinal evidence on the nativity health gap in Australia. We investigated whether differences exist in the reporting of any chronic condition (including cancer, cardiovascular disease (CVD), arthritis, diabetes and respiratory disease), and in the total number of chronic conditions, between foreign-born (FB) from English speaking (ES) and non-English speaking (NES) countries and native-born (NB) Australians. We also investigated differences between these groups in the reporting of any chronic condition, and the total number of chronic conditions, by duration of residence. After adjusting for time varying and time invariant covariates, we found a significant difference by nativity status in the reporting of chronic condition, with immigrants from both ES and NES countries less likely to report a chronic condition and having fewer chronic conditions compared with the NB. Immigrants from both ES and NES countries living in Australia for less than 20 years were significantly less likely to report a chronic condition compared with the NB. However, the health of both these groups converged to that of the NB population in terms of reporting a chronic condition after 20 years of stay in Australia.

The association of percentage energy from fat and colon cancer risk among members of the US military

Epidemiologic studies have previously reported an association between high fat intake and colon cancer risk. However, findings have generally been inconclusive. This study aimed to investigate the association between fat as a percentage of energy intake and colon cancer risk. Study subjects included 215 cases and 215 matched controls identified by the Defense Medical Surveillance System. Percentage energy from fat (Pfat) was estimated using a short dietary screener developed by the National Cancer Institute for two time periods: the year before the first blood draw and the year before colon cancer diagnosis. Conditional logistic regression analysis was used to assess the relationship between colon cancer risk and Pfat. Odds ratios and 95% confidence intervals (CIs) were calculated. Compared with the lowest quartile of Pfat, the adjusted odds of having colon cancer were 2.00 (95% CI 0.96-4.18), 2.83 (95% CI 1.41-5.66), and 3.37 (95% CI 1.58-7.17), respectively, for the second, third, and highest quartiles in the year before cancer diagnosis. Similar results were observed for Pfat at an earlier time point. Our findings suggest a positive association between Pfat and colon cancer in the US military population.

Dietary changes in Vietnamese marriage immigrant women: The KoGES follow-up study

BACKGROUND/OBJECTIVES

The immigrant population has grown considerably in South Korea since the early 1990s due to international marriages. Dietary changes in immigrants are an important issue, because they are related to health and disease patterns. This study was conducted to compare changes in dietary intake between baseline and follow-up periods.

SUBJECTS/METHODS

Two hundreds thirty three Vietnamese female married immigrants. Baseline data were collected during 2006-2009, and the follow-up data were collected during 2008 and 2010. Food consumption was assessed using a 1-day 24-hour recall.

RESULTS

The amount of the total food consumed (P < 0.001) including that of cereals (P = 0.004), vegetables (P = 0.003), and fruits (P = 0.002) decreased at follow-up compared to that at baseline, whereas consumption of milk and dairy products increased (P = 0.004). Accordingly, the overall energy and nutrient intake decreased at follow-up, including carbohydrates (P = 0.012), protein (P = 0.021), fiber (P = 0.008), iron (P = 0.009), zinc (P = 0.006), and folate (P = 0.002). Among various anthropometric and biochemical variables, mean skeletal muscle mass decreased (P = 0.012), plasma high density lipoprotein-cholesterol increased, (P = 0.020) and high sensitivity C-reactive protein decreased at follow-up (P < 0.001).

CONCLUSIONS

A long-term follow-up study is needed to investigate the association between changes in food and nutrient intake and anthropometric and biochemical variables in these Vietnamese female marriage immigrants.

Association of sedentary behaviour with colon and rectal cancer: a meta-analysis of observational studies

BACKGROUND

Sedentary behaviour is ubiquitous in modern society. Emerging studies have focused on the health consequences of sedentary behaviour, including colorectal cancer, but whether sedentary behaviour is associated with the risks of colon and rectal cancer remains unclear. No systematic reviews have applied quantitative techniques to independently compute summary risk estimates. We aimed to conduct a meta-analysis to investigate this issue.

METHODS

We searched PubMed, Embase, and Google Scholar databases up to May 2013 to identify cohort and case-control studies that evaluated the association between sedentary behaviour and colon or rectal cancer. A random-effect model was used to pool the results of included studies. Publication bias was assessed by using Begg's funnel plot.

RESULTS

Twenty-three studies with 63 reports were included in our meta-analysis. These groups included 4,324,462 participants (27,231 colon cancer cases and 13,813 rectal cancer cases). Sedentary behaviour was significantly associated with colon cancer (relative risk (RR): 1.30, 95% confidence interval (CI): 1.22-1.39) but did not have a statistically significant association with rectal cancer (RR 1.05, 95% CI, 0.98-1.13). Subgroup analyses suggested that the odds ratio (OR) of colon cancer was 1.46 (95% CI: 1.22-1.68) in the case-control studies, and the RR was 1.27 (95% CI: 1.18-1.36) in the cohort studies, the OR of rectal cancer was 1.06 (95% CI: 0.85-1.33) in the case-control studies, and the RR was 1.06 (95% CI, 1.01-1.12) in the cohort studies.

CONCLUSION

Sedentary behaviour is associated with an increased risk of colon cancer. Subgroup analyses suggest a positive association between sedentary behaviour and risk of rectal cancer in cohort studies. Reducing sedentary behaviour is potentially important for the prevention of colorectal cancer.

Prevalence of adenomas and sessile serrated adenomas in Chinese compared with Caucasians

BACKGROUND AND AIMS

Colonic adenomas and sessile serrated adenomas (SSA) are the most common premalignant polyps identified at colonoscopy. This study compares the prevalence of neoplastic polyps in Chinese and Caucasians in a general gastroenterology outpatient practice in Australia.

METHODS

This study included consecutive unselected colonoscopies performed for standard clinical indications by a single endoscopist (JMH). All polyps detected were measured, resected, and sent for histopathology. The prevalence of adenomas, advanced adenomas, SSA, and cancer in the Chinese and Caucasian cohorts were compared. Advanced adenomas were defined as adenomas > 10 mm, villous histology, or high-grade dysplasia.

RESULTS

The study included 346 Chinese and 654 Caucasians. There was no significant difference in the baseline characteristics including age, gender, and indications of colonoscopy, although Chinese were more likely to present with rectal bleeding (22.8% vs 15.9%, P = 0.01). The prevalence of adenomatous polyps was similar in both Caucasians (34.3%) and Chinese (35.3%). However, advanced adenomas were more significantly common in Caucasians (11.3%) compared with Chinese (4.6%) (P < 0.001). SSA was rare in Chinese (2%) but present more frequently in Caucasians (7%) (P = 0.001). Multivariate analysis showed that Caucasian ethnicity (odds ratio 2.4, 95% confidence interval 1.6-3.6) and the presence of SSA (odds ratio 4.4, 95% confidence interval 2.3-8.6) were independent predictors for the detection of an advanced adenoma.

CONCLUSIONS

The prevalence of significant colorectal lesions, including advanced adenomas, large adenomas, and SSA, were lower in Chinese compared with Caucasians. These findings may influence the guidelines for colonic cancer screening in Chinese populations.

Chicken skin mucosa surrounding adult colorectal adenomas is a risk factor for carcinogenesis

OBJECTIVES

Transformation of normal mucosa to colorectal adenoma could occur over a span of 5 to 20 years, whereas transformation of colorectal adenoma to colorectal cancer could take an additional 5 to 15 years. This study aims to investigate whether chicken skin mucosa (CSM) surrounding adult colorectal adenomas may be a risk factor for carcinogenesis.

METHODS

Patients with colorectal mucosa, colorectal adenomas without CSM, or colorectal adenomas with CSM were enrolled in this study. Immunohistochemistry and enzyme-linked immunosorbent assays were used to determine the expression levels of proliferation markers (ki-67 and COX-2) and apoptosis factors (survivin and caspase-3) in tissues.

RESULTS

The expression of ki-67 was significantly higher in colorectal adenomas with CSM compared with colorectal adenoma tissues (P < 0.01). Colorectal adenocarcinoma showed significantly higher levels of COX-2 protein compared with normal colorectal mucosa and colorectal adenoma tissues (P < 0.001). COX-2 expression was significantly higher in adenomas with CSM compared with normal colorectal mucosa (P < 0.001). Adenomas with CSM and adenocarcinomas exhibited significantly higher levels of survivin when compared with colorectal adenoma without CSM and normal tissues (P < 0.001). Although we found no significant difference in caspase-3 levels between adenocarcinomas and adenomas with CSM, caspase-3 expression was significantly lower in these tissues when compared with colorectal adenomas without CSM and normal mucosa (P < 0.001).

CONCLUSIONS

The biological characteristics of colorectal adenomas with CSM were different from those of colorectal adenomas without CSM. Colorectal adenomas with CSM exhibited active cell proliferation and inhibition of apoptotic pathways, suggesting an increased risk of carcinogenesis in these adenomas.

Associations of recreational physical activity and leisure time spent sitting with colorectal cancer survival

PURPOSE

Little is known about the association of recreational physical activity or leisure time spent sitting with survival after colorectal cancer diagnosis. This study examined the associations of prediagnosis and postdiagnosis recreational physical activity and leisure time spent sitting with mortality among patients with colorectal cancer.

PATIENTS AND METHODS

From a cohort of adults without colorectal cancer at baseline in 1992-1993, we identified 2,293 participants who were diagnosed with invasive, nonmetastatic colorectal cancer up to mid-2007. At baseline, before their cancer diagnosis, and again after their cancer diagnosis, participants completed detailed questionnaires that included information concerning recreational physical activity and leisure time spent sitting.

RESULTS

During a maximum follow-up of 16.1 years after colorectal cancer diagnosis, 846 patients with colorectal cancer died, 379 of them from colorectal cancer. Engaging in 8.75 or more metabolic equivalent (MET) hours per week of recreational physical activity (equivalent to approximately 150 minutes per week of walking) compared with fewer than 3.5 MET hours per week was associated with lower all-cause mortality (prediagnosis physical activity: relative risk [RR], 0.72; 95% CI, 0.58 to 0.89; postdiagnosis physical activity: RR, 0.58; 95% CI, 0.47 to 0.71). Spending 6 or more hours per day of leisure time sitting compared with fewer than 3 hours per day was associated with higher all-cause mortality (prediagnosis sitting time: RR, 1.36; 95% CI, 1.10 to 1.68; postdiagnosis sitting time: RR, 1.27; 95% CI, 0.99 to 1.64).

CONCLUSION

More recreational physical activity before and after colorectal cancer diagnosis was associated with lower mortality, whereas longer leisure time spent sitting was associated with higher risk of death.

Physical activity and risks of proximal and distal colon cancers: a systematic review and meta-analysis

BACKGROUND

Although there is convincing epidemiological evidence that physical activity is associated with a reduced risk of colon cancer, it is unclear whether physical activity is differentially associated with the risks of proximal colon and distal colon cancers. We conducted a systematic review and meta-analysis to investigate this issue.

METHODS

MEDLINE and EMBASE were searched for English-language cohort and case-control studies that examined associations between physical activity and the risks of proximal colon and distal colon cancers. A random-effects meta-analysis was conducted to estimate the summary relative risks (RRs) for the associations between physical activity and the risks of the two cancers. All statistical tests were two-sided.

RESULTS

A total of 21 studies met the inclusion criteria. The summary relative risk of the main results from these studies indicated that the risk of proximal colon cancer was 27% lower among the most physically active people compared with the least active people (RR = 0.73, 95% confidence interval [CI] = 0.66 to 0.81). An almost identical result was found for distal colon cancer (RR = 0.74, 95% CI = 0.68 to 0.80).

CONCLUSION

The results of this systematic review and meta-analysis suggest that physical activity is associated with a reduced risk of both proximal colon and distal colon cancers, and that the magnitude of the association does not differ by subsite. Given this finding, future research on physical activity and colon cancer should focus on other aspects of the association that remain unclear, such as whether sedentary behavior and nonaerobic physical activity are associated with the risk of colon cancer.

Physical Activity and Colon Cancer

Despite the convincing evidence that physical activity reduces the risk of colon cancer, there are some aspects of the association that remain unclear. These include the appropriate timeframe of exposure, whether the intensity of physical activity matters, and whether sedentary behavior is a distinct risk factor. This review summarized the research that has investigated these issues. In terms of timing, physical activity at any age (with the exception of physical activity performed up to and including the late teens) has been shown to be associated with a significantly reduced risk of colon cancer. Physical activity performed between 30 and 50 years of age, as well as long-term or lifetime physical activity, has been most consistently shown to reduce risk. For intensity, research to date suggests that more intense activity (particularly vigorous activity) may be associated with a greater reduction in the risk of colon cancer for males but not for females. Finally, most of the studies that have investigated the effect of sedentary behavior on the risk of colon or colorectal cancer have shown an increased risk, suggesting that sedentary behavior may be a distinct risk factor for colon cancer.

The association between active participation in a sports club, physical activity and social network on the development of lung cancer in smokers: a case-control study

BACKGROUND

This study analyses the effect of active participation in a sports club, physical activity and social networks on the development of lung cancer in patients who smoke. Our hypothesis is that study participants who lack social networks and do not actively participate in a sports club are at a greater risk for lung cancer than those who do.

METHODS

Data for the study were taken from the Cologne Smoking Study (CoSmoS), a retrospective case-control study examining potential psychosocial risk factors for the development of lung cancer. Our sample consisted of n = 158 participants who had suffered lung cancer (diagnosis in the patient document) and n = 144 control group participants. Both groups had a history of smoking.Data on social networks were collected by asking participants whether they participated in a sports club and about the number of friends and relatives in their social environment. In addition, sociodemographic data (gender, age, education, marital status, residence and religion), physical activity and data on pack years (the cumulative number of cigarettes smoked by an individual, calculated by multiplying the number of cigarettes smoked per day by the number of years the person has smoked divided by 20) were collected to control for potential confounders. Logistic regression was used for the statistical analysis.

RESULTS

The results reveal that participants who are physically active are at a lower risk of lung cancer than those who are not (adjusted OR = 0.53*; CI = 0.29-0.97). Older age and lower education seem also to be risk factors for the development of lung cancer. The extent of smoking, furthermore, measured by pack years is statistically significant. Active participation in a sports club, number of friends and relatives had no statistically significant influence on the development of the cancer.

CONCLUSIONS

The results of the study suggest that there is a lower risk for physically active participants to develop lung cancer. In the study sample, physical activity seemed to have a greater protective effect than participation in a sports club or social network of friends and relatives. Further studies have to investigate in more detail physical activity and other club participations.

Population versus hospital controls for case-control studies on cancers in Chinese hospitals

BACKGROUND

Correct control selection is crucial to the internal validity of case-control studies. Little information exists on differences between population and hospital controls in case-control studies on cancers in Chinese hospital setting.

METHODS

We conducted three parallel case-control studies on leukemia, breast and colorectal cancers in China between 2009 and 2010, using population and hospital controls to separately match 540 incident cases by age, gender and residency at a 1:1 ratio. Demographic and lifestyle factors were measured using a validated questionnaire in face-to-face interview. Odds ratios (ORs) and 95% confidence intervals (CIs) were obtained using conditional logistic regression analyses.

RESULTS

The two control groups had closely similar exposure distributions of 15 out of 16 factors, with the only exception being that hospital controls were less likely to have a BMI ≥ 25 (OR = 0.71, 95% CI: 0.54, 0.93). For exposure of green tea drinking, the adjusted ORs (95% CIs) comparing green tealeaves intake ≥ 1000 grams annually with non-drinkers were 0.51 (0.31, 0.83) and 0.21 (0.27, 0.74) for three cancers combined, 0.06 (0.01, 0.61) and 0.07 (0.01, 0.47) for breast cancer, 0.52 (0.29, 0.94) and 0.45 (0.25, 0.82) for colorectal cancer, 0.65 (0.08, 5.63) and 0.57 (0.07, 4.79) for leukemia using hospital and population controls respectively.

CONCLUSIONS

The study found that hospital controls were comparable with population controls for most demographic characteristics and lifestyle factors measured, but there was a slight difference between the two control groups. Hospital outpatients provide a satisfactory control group in hospital-based case-control study in the Chinese hospital setting.

Performance of a colorectal cancer screening protocol in an economically and medically underserved population

The performance of combining fecal immunochemical tests (FITs) and a high-risk factor questionnaire (HRFQ) in colorectal cancer (CRC) screening in economically and medically underserved populations is uncertain. This study investigated the performance of a CRC screening protocol of combining FITs and an HRFQ as primary screening methods in a rural Chinese population. A CRC mass screening was conducted using FITs and an HRFQ as the first and colonoscopy as the second stage of screening in Jiashan, 2007-2009. The target population was 31,963 residents in three communities. The compliance was 84.7% for HRFQ, 76.4% for FITs, and 78.7% for colonoscopy. The detected rates of cancer, adenoma, nonadenomatous polyps, and advanced neoplasm were 2.7%, 14.8%, 5.9%, and 8.9% by FITs, which were higher than those by HRFQ (0.5%, 9.2%, 4.8%, and 3.8%, respectively). There was no significant difference in detected rate for nonadenomatous polyps between FITs and HRFQ. A total of 41.2% adenomas, 53.2% nonadenomatous polyps, and 29.8% advanced neoplasms were detected by HRFQ but missed by FITs. Positive predictive value of the screening protocol of combining FITs and HRFQ for advanced neoplasm was 5.7%, which was higher than FITs alone. Men had a higher prevalence of advanced neoplasm than women. Results indicate that combining FITs and HRFQ as primary screening methods is an efficient CRC screening strategy in economically and medically underserved populations.

Green tea consumption and colorectal cancer risk: a report from the Shanghai Men's Health Study

Tea and its constituents have demonstrated anticarcinogenic activity in both in vitro and in vivo animal studies. Results from epidemiologic studies, however, have been inconsistent. Some factors that coexist with tea consumption, such as cigarette smoking, may confound or modify the association between tea consumption and cancer risk. The objective of this study was to comprehensively evaluate the association between green tea consumption and colorectal cancer risk in a population-based prospective cohort study, the Shanghai Men's Health Study. The analysis included 60,567 Chinese men aged 40-74 years at baseline. During ∼5 years of follow-up, 243 incident cases of colorectal cancer were identified. Multivariable Cox regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) of developing colorectal cancer. Regular green tea consumption (ever drank green tea at least three times per week for more than six consecutive months) was associated with reduced risk of colorectal cancer in non-smokers (multivariable-adjusted HR = 0.54, 95% CI: 0.34-0.86). The risk decreased as the amount of green tea consumption increased (P(trend) = 0.01). Each 2 g increment of intake of dry green tea leaves per day (approximately equivalent to the amount of tea in a tea bag) was associated with a 12% reduction in risk (HR = 0.88, 95% CI: 0.78-0.99). No significant association was found among smokers (HR = 0.94, 95% CI: 0.66-1.34). This study suggests that regular consumption of green tea may reduce colorectal cancer risk among non-smokers.

Low-to-moderate alcohol intake and breast cancer risk in Chinese women

BACKGROUND

Despite extensive investigation of the association between alcohol consumption and breast cancer risk, effect of low-to-moderate alcohol intake on breast cancer incidence has been inconsistent.

METHODS

A case-control study was conducted in China, 2004-2005 to examine the association by menopausal status, oestrogen (ER) and progesterone receptor (PR) status of the tumour. There were 1009 incident cases with histologically confirmed breast cancer and 1009 age-matched controls recruited. We assessed alcohol consumption by face-to-face interview using a validated questionnaire and obtained tumour ER and PR status from pathology reports.

RESULTS

Low-to-moderate alcohol consumption was inversely associated with breast cancer risk. Compared with nondrinkers, the adjusted odds ratios (ORs) for alcohol <5 g per day were 0.41 (95% confidence interval 0.27-0.62) and 0.62 (0.48-0.79) in postmenopausal and premenopausal women, respectively. The inverse association was consistent for alcohol <15 g per day across hormone receptor status groups with ORs of 0.36-0.56 in postmenopausal women and 0.57-0.64 in premenopausal women. An exception was that alcohol ≥15 g per day appeared to increase the risk of breast cancers with discordant receptor status in postmenopausal women, that is, ER+/PR- or ER-/PR+ (4.27, 1.57-11.65).

CONCLUSION

We found that low-to-moderate alcohol intake was not associated with increased risk of breast cancer in pre- or postmenopausal Chinese women. Future studies are required to understand differences in effect of alcohol on breast cancers by tumour hormone receptor status.

Long-term sedentary work and the risk of subsite-specific colorectal cancer

Research suggests that sedentary behavior may increase the risk of some chronic diseases. The aims of the study were to examine whether sedentary work is associated with colorectal cancer and to determine whether the association differs by subsite. A total of 918 cases and 1,021 controls participated in a population-based case-control study of colorectal cancer in Western Australia in 2005-2007. Data were collected on lifestyle, physical activity, and lifetime job history. The estimated effects of sedentary work on the risk of cancers of the proximal colon, distal colon, and rectum were analyzed by using multinomial logistic regression. Compared with participants who did not spend any time in sedentary work, participants who spent 10 or more years in sedentary work had almost twice the risk of distal colon cancer (adjusted odds ratio = 1.94, 95% confidence interval: 1.28, 2.93) and a 44% increased risk of rectal cancer (adjusted odds ratio = 1.44, 95% confidence interval: 0.96, 2.18). This association was independent of recreational physical activity and was seen even among the most recreationally active participants. Sedentary work was not associated with the risk of proximal colon cancer. These results suggest that long-term sedentary work may increase the risk of distal colon cancer and rectal cancer.

Dietary glycemic load and risk of colorectal cancer in Chinese women

BACKGROUND

Mixed results have been reported in recent epidemiologic studies in Western populations that have investigated the hypothesis that high glycemic load may increase the risk of colorectal cancer. This association has not been prospectively evaluated in other populations.

OBJECTIVE

We examined the association of overall glycemic index and glycemic load with colorectal cancer risk in a prospective cohort of Chinese women.

DESIGN

A total of 73,061 women aged 40-70 y and free of cancer at enrollment were included in this analysis. Usual dietary intake was assessed at baseline (1997-2000) and reassessed during the first follow-up (2000-2002) through in-person interviews by using a validated food-frequency questionnaire.

RESULTS

During an average follow-up of 9.1 y, 475 incident colorectal cancer cases were identified. Glycemic load was not associated with colorectal cancer risk (P for trend = 0.84). The multivariable hazard ratio for the highest compared with the lowest quintile of glycemic load was 0.94 (95% CI: 0.71, 1.24). Similar results were also observed for associations with dietary glycemic index and total carbohydrate intake, and results did not vary by excluding individuals with a history of diabetes from the analysis.

CONCLUSION

This prospective study, conducted in a population with a high intake of carbohydrates, provides no evidence that a high-glycemic index diet or high glycemic load is associated with an increased risk of colorectal cancer.

Effect of dietary intake of isoflavones on the estrogen and progesterone receptor status of breast cancer

To examine if higher intake of isoflavones prior to diagnosis was associated with a positive status of estrogen receptors (ER) and progesterone receptors (PR) in breast tumor tissue, a retrospective study was conducted in 2004 to 2005 in 756 Chinese women with histologically confirmed breast cancer. We administered a food frequency questionnaire by face-to-face interview to assess the intake of the isoflavones daidzein and genistein. Unconditional logistic regression analysis was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) adjusted for potential confounders. Comparing the highest to lowest intake quartiles, the adjusted ORs for daidzein were 1.94 (95% CI = 1.20-3.32) and 2.18 (95% CI = 1.28-3.73) for ER positive and PR positive tumors, respectively, in premenopausal patients. The ORs for both ER and PR positive status combined were 2.48 (95% CI = 1.37-4.49) for daidzein and 1.94 (95% CI = 1.21-3.14) for genistein in premenopausal patients with statistically significant tests for trend. There was little or no evidence of associations in postmenopausal patients. We conclude that higher intake of daidzein and genistein before diagnosis was associated with ER and PR positive status in premenopausal Chinese women with breast cancer. The association might confer a more favorable prognosis.

Fruit and vegetable intakes are associated with lower risk of breast fibroadenomas in Chinese women

Fibroadenomas are common benign breast conditions among women and account for approximately 50% of breast biopsies performed. Dietary factors are known to influence benign breast conditions in the aggregate, but little is known of their association specifically with fibroadenoma. Our objective in this study was to evaluate the association between dietary and other factors and fibroadenoma risk. A case-control study, nested in a randomized trial of breast self-examination (BSE) in Chinese textile workers in Shanghai, China, was conducted between 1989 and 2000. The study sample included 327 affected women and 1070 controls. Women were administered a FFQ and a questionnaire that elicited reproductive and gynecological history and other information. Odds ratios, as estimates of relative risks, were calculated using multivariate conditional logistic regression. Significant decreasing trends in risk of fibroadenoma were observed with intake of fruits and vegetables and with number of live births, and a reduced risk was also associated with natural menopause, oral contraceptive use, and moderate exercise (walking and gardening). Increased risk of fibroadenoma was associated with heavy physical activity in one's 20s, breast cancer in a first-degree relative, and a history of prior benign breast lumps; and significant increasing trends in risk were observed with numbers of BSE per year and years of education. In conclusion, a diet rich in fruits and vegetables and the use of oral contraceptives may reduce risk of fibroadenoma.

Menopausal transition and changes of body composition: a prospective study in Chinese perimenopausal women

OBJECTIVES

Whether age or menopause per se influences fat distribution remains controversial. This study aimed to investigate the change of body composition, particularly body fat distribution, in relation to menopausal transition in a 30-month prospective study of perimenopausal women.

METHODS

A total of 438 community-based healthy women aged 44-55 years participated in the Hong Kong Perimenopausal Women Osteoporosis Study. Data were obtained at baseline, and at 9-, 18- and 30-month during the follow-up. Soft tissue measurements consisting of fat mass and lean muscle mass of the trunk and whole body were obtained by the dual energy X-ray absorptiometry. Percentage change of body measurements over the follow-up period was compared between women who remained premenopausal, those who went through menopausal transition, and those who were menopausal since baseline.

RESULTS

A slight decrease in the lean mass but an increase in the total fat mass and trunk fat mass (TFM) over the follow-up period were noted. Multivariate linear regression analysis showed that age was negatively associated with an increase in central obesity. Adjusted for the important predictors--age, age of menarche and education level, menopausal status was a significant and independent predictor of the decrease in lean mass and the increase in percent of body fat, TFM and trunk-leg fat mass ratio.

CONCLUSION

Our 30-month longitudinal study showed that menopause has an independent effect on an increase in fat mass, and an increase in central obesity in perimenopausal Chinese women.

Establishment and characterization of 13 human colorectal carcinoma cell lines: mutations of genes and expressions of drug-sensitivity genes and cancer stem cell markers

Thirteen human colorectal cancer (CRC) cell lines were established from 10 primary tumors and 3 metastatic tumors obtained from 13 Korean patients. Characteristics of the cell lines including morphology in vivo and in vitro; mutations of the K-ras, p53, APC and MMR genes and microsatellite instability (MSI) status in vitro were determined. Expression of drug-sensitivity genes including MDR1, MXR, MRP1 and COX2 was also analyzed. The cell lines were unique as judged by DNA fingerprinting using 16 short tandem repeats. Eleven of the cell lines grew as adherent populations and the remaining two as floating aggregates. None of the cell lines were contaminated with Mycoplasma or bacteria. All cell lines showed high viability with relatively long doubling times. Six cell lines contained mutations at K-ras. Seven cell lines displayed p53 gene missense, nonsense and frameshift mutations. MSI was found in three cell lines and two cell lines with an MSI-high phenotype-possessed hMLH1 mutations. Nine cell lines had an APC mutation. MRP1 was highly expressed in all cell lines, and high expression of MDR1, MXR and COX2 evident in eight, six and six cell lines, respectively. Embryonal stem cell markers (MELK, SOX4 and OCT4) were expressed in most of cell lines. The cancer stem cell biomarkers CD133, CD44 and Lgr5 were expressed in 12, 13 and 13 cell lines, respectively. The presently well-characterized CRC cell lines should be useful in investigations of the biological characteristics of CRC, particularly for investigations related to gene alterations associated with CRC and biology of cancer stem cells.

Physical activity and gastrointestinal cancer prevention

Colorectal cancer is the third most common cancer globally and is a leading cause of cancer death. Gastric cancer contributes significantly to the global cancer burden, particularly in low- and middle-income countries. We reviewed the literature for studies on physical activity or exercise and colon, rectal, and gastric cancers as well as colonic adenomatous polyps. We identified 52 studies of colon cancer, 31 studies of rectal cancer, 23 studies of colon polyps, and 16 studies of gastric cancer. Of the 52 studies of physical activity and colon cancer, 37 found a statistically significant association between increased levels of physical activity and decreased colon cancer risk in at least one comparison. Accumulated evidence suggests that physical activity is associated with a 25% reduction in colon cancer risk. In line with previous reports, we found no indication that the association was more pronounced for occupational versus recreational physical activity, with both resulting in a risk reduction of about 22%. Evidence for other domains of physical activity (i.e., transportation or household physical activity) is limited. Evidence is emerging that individuals who are consistently active across the lifetime may obtain greater risk reductions than those who are only active in recent years. Despite consistent associations with colon cancer, evidence is more limited though suggestive that physical activity reduces risk of colon adenomas or adenoma recurrence. There is clear evidence that physical activity is not associated with rectal or gastric cancers.

A quantitative analysis of body mass index and colorectal cancer: findings from 56 observational studies

To perform a systematic review of studies reporting on the association between body mass index (BMI) and the risk of colorectal cancer, we conducted a meta-analysis and meta-regression analysis. The identified 56 studies were conducted among 7 213 335 individuals including 93 812 cases. Compared with BMI < 23.0 kg m(-2), BMI of 23.0-24.9, 25.0-27.4, 27.5-29.9 and > or = 30.0 kg m(-2) were associated with 14%, 19%, 24% and 41% increased risks, respectively. Asians and premenopausal women had sharply increased risk from BMI < 23 kg m(-2) to general 'normal' range (23-25 kg m(-2)). Each 5 kg m(-2) increment was associated with 18% increased risk. Meta-regression analysis indicated that the association was stronger for colon than rectal cancer (P < 0.001), for men than women (P < 0.001), for self-reported BMI than directly measured BMI (P < 0.001), and for studies adjusting for physical activity than not adjusting (P < 0.001). The variation of the reported risk estimates for the association can be partly explained by cancer site, sex, women menopausal status, BMI assessment and adjustment of confounding variables.

Physical activity, obesity and risk for esophageal adenocarcinoma

Over the past three decades, an increasing incidence of esophageal adenocarcinoma (EADC) has been reported throughout North America and Europe at a rate exceeding that of any other human solid tumor. Recent studies have clearly implicated chronic gastroesophageal reflux disease and several lifestyle risk factors, including tobacco consumption, diet and obesity, to be associated with increased risk of EADC. Although physical inactivity is now recognized as a risk factor for several chronic diseases including cancer, only a very limited number of studies have specifically evaluated the association between physical activity and esophageal malignancy. Furthermore, the precise biological mechanisms underlying the association between physical activity, obesity and cancer risk remain unclear. Since successful promotion of healthy body weight and exercise may substantially reduce the future incidence of cancer in the population, the purpose of this review is to explore current evidence linking physical activity, obesity and risk of malignancy – specifically EADC.

Dietary habits and health beliefs of Chinese Canadians

PURPOSE

The relationships among dietary behaviours, traditional health beliefs (THB), and demographic characteristics of Chinese Canadians living in Toronto were examined, as were their primary sources of nutrition information.

METHODS

Through the use of probability sampling, 106 adult subjects who originated from China, Hong Kong, or Taiwan were recruited from five Chinese community organizations. A telephone interview, employing a tested questionnaire, was conducted in Cantonese or Mandarin. All data were analyzed with MS Excel and SPSS statistical software.

RESULTS

Dietary acculturation is gradual and individual. Participants reported regular intakes of fruits and vegetables and fat-reducing behaviours. Most used both Chinese and Western cooking methods. Practices based on traditional Chinese health beliefs (THB), such as balancing yin and yang foods to promote health, were prevalent. Participants were grouped as THB-strong, THB-moderate, or THB-weak, on the basis of their health belief scores. Various significant relationships among the variables were identified. Chinese media, friends, and family were the primary sources of nutrition information; dietitians were identified by only 12%.

CONCLUSIONS

This is the first study to apply a THB grouping for Chinese Canadians. Results will provide an important basis for nutrition interventions to encourage immigrants to make healthy food choices, using both traditional and Western foods.