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1.
Dietary calcium, vitamin D, VDR genotypes and colorectal cancer   总被引:7,自引:0,他引:7  
The vitamin D receptor (VDR) may importantly modulate risk of colorectal cancer either independently or in conjunction with calcium and vitamin D intake. We evaluate the association between calcium, vitamin D, dairy products, and VDR polymorphisms in 2 case-control studies of colon and rectal cancer (n = 2,306 cases and 2,749 controls). Dietary intake was evaluated using a detailed diet history questionnaire. Two VDR polymorphisms were evaluated: an intron 8 Bsm 1 polymorphism and a 3' untranslated region poly-A length polymorphism (designated S for short and L for long). The SS genotype reduced risk of colorectal cancer for men (odds ratio [OR] = 0.71; 95% confidence interval [CI] = 0.55-0.92). High levels of calcium intake reduced risk of rectal cancer in women (OR = 0.39; 95% CI = 0.24-0.64) but were not associated with rectal cancer in men (OR = 1.02; 95% CI = 0.66-1.56). Similar reduced rectal cancer risk among women was observed at high levels of vitamin D (OR = 0.52; 95% CI = 0.32-0.85) and low-fat dairy products (OR = 0.61; 95% CI = 0.39-0.94). High levels of sunshine exposure reduced risk of rectal cancer among those diagnosed when <60 years of age (OR = 0.62, 95% CI = 0.42-0.93). Examination of calcium in conjunction with VDR genotype showed that a significant 40% reduction in risk of rectal cancer was observed for the SS or BB VDR genotypes when calcium intake was low (p interaction = 0.01 for calcium interaction). For colon cancer, high levels of dietary intake of calcium, vitamin D, and low-fat dairy products reduced risk of cancer for the SS or BB VDR genotypes, although the p for interaction was not statistically significant. These data support previous observations that high levels of calcium and vitamin D reduce risk of rectal cancer and provide support for a weak protective effect for the SS and BB VDR genotypes. The risk associated with VDR genotype seems to depend upon the level of dietary calcium and vitamin D and tumor site.  相似文献   

2.
Objective: Few data exist regarding the association between calcium intake and adenoma recurrence, and no data exist for vitamin D. We investigated the role of dietary and supplemental sources of calcium and vitamin D in the etiology of adenoma recurrence. Methods: Analyses were conducted among 1304 male and female participants in the Wheat Bran Fiber (WBF) trial of adenoma recurrence. Multiple logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs). Results: In the fully adjusted multivariate model, the OR for participants with dietary calcium intake above 1068 versus those with intake below 698 mg/day was 0.56 (95% CI = 0.39–0.80; p-trend = 0.007). Calcium supplementation at doses above 200 mg/day did not affect risk of recurrence. Although a borderline inverse association between dietary vitamin D and recurrence was observed after adjustment for age and gender, the association weakened in the fully adjusted model (OR = 0.78 for individuals in the upper compared to the lower quartile; 95% CI = 0.54–1.13). No association was shown for supplemental sources of vitamin D. Conclusions: Results of this study indicate that a higher intake of calcium decreases the risk of adenoma recurrence by approximately 45%, whereas vitamin D has no significant effect on recurrence rates.  相似文献   

3.
Objective: Calcium, vitamin D, and dairy product intake may reduce the risk of colorectal cancer. We therefore examined the association between these factors and risk of colorectal cancer in a large prospective cohort of United States men and women. Methods: Participants in the Cancer Prevention Study II Nutrition Cohort completed a detailed questionnaire on diet, medical history, and lifestyle in 1992–93. After excluding participants with a history of cancer or incomplete dietary information, 60,866 men and 66,883 women remained for analysis. During follow-up through 31 August 1997 we documented 421 and 262 cases of incident colorectal cancers among men and women, respectively. Multivariate-adjusted rate ratios (RR) were calculated using Cox proportional hazards models. Results: Total calcium intake (from diet and supplements) was associated with marginally lower colorectal cancer risk in men and women (RR = 0.87, 95% CI 0.67–1.12, highest vs lowest quintiles, p trend = 0.02). The association was strongest for calcium from supplements (RR = 0.69, 95% CI 0.49–0.96 for 500 mg/day vs none). Total vitamin D intake (from diet and multivitamins) was also inversely associated with risk of colorectal cancer, particularly among men (RR = 0.71, 95% CI 0.51–0.98, p trend = 0.02). Dairy product intake was not related to overall risk. Conclusions: Our results support the hypothesis that calcium modestly reduces risk of colorectal cancer. Vitamin D was associated with reduced risk of colorectal cancer only in men.  相似文献   

4.
Vitamin D receptor (VDR) activation inhibits proliferation and angiogenesis in the colorectal epithelium, and inhibits metastasis of colorectal tumors. Polymorphisms in the VDR gene alter receptor cellular levels and functioning, and may confer altered susceptibility to colorectal neoplasia. We aimed to investigate the influence of VDR polymorphisms and dietary factors impacting on vitamin D metabolism on colorectal adenoma (CRA) recurrence. Data on dietary intakes of calcium, vitamin D and dairy products were collected from 853 participants in the United Kingdom Colorectal Adenoma Prevention trial, a randomized trial of aspirin and folate for CRA recurrence prevention. The VDR Cdx2, FokI, BsmI, ApaI and TaqI polymorphisms were genotyped in 546 participants with available DNA, and gene-diet interaction analyses performed in 480. Dairy product intake was inversely related to CRA recurrence risk independent of calcium and vitamin D [relative risk (RR) = 0.64; 95% confidence intervals (CIs): 0.47-0.88, for subjects in the highest compared to lowest intake tertile, p(trend) = 0.005]. Milk accounted for 60% of dairy product intake, and on analysis of milk and nonmilk dairy products separately recurrence risk in individuals in the highest tertile of milk intake was half that of lowest tertile individuals (RR = 0.52; 95% CI: 0.38-0.72, p(trend) = 3.2 x 10(-5)), whereas nonmilk dairy products did not influence recurrence. VDR polymorphism genotypes and haplotypes did not directly alter recurrence risk, but the reduction in risk associated with high dairy product intake was confined to individuals with ApaI aA/AA genotype (p(interaction) = 0.02). These findings indicate dairy products, and in particular milk, have chemopreventive activity against CRA recurrence.  相似文献   

5.
High dietary intakes of calcium and dairy products have been hypothesized to enhance prostate cancer risk, but available prospective data regarding these associations are inconsistent. We examined dietary intakes of calcium and dairy products in relation to risk of prostate cancer in the Alpha-Tocopherol, Beta-Carotene (ATBC) Cancer Prevention Study, a cohort of 29,133 male smokers aged 50-69 years at study entry. Dietary intake was assessed at baseline using a validated 276-item food use questionnaire. Cox proportional hazards regression was used to adjust for known or suspected risk factors for prostate cancer. During 17 years of follow-up, we ascertained 1,267 incident cases of prostate cancer. High versus low intake of dietary calcium was associated with a marked increase in prostate cancer risk. The multivariate relative risk (RR) of prostate cancer for > or =2,000 mg/day compared to <1,000 mg/day of calcium intake was 1.63 (95% confidence interval (CI), 1.27-2.10; p trend < 0.0001). Total dairy intake was also positively associated with risk of prostate cancer. The multivariate RR of prostate cancer comparing extreme quintiles of intake was 1.26 (95% CI, 1.04-1.51; p trend = 0.03). However, no association with total dairy intake remained after we adjusted for calcium (p trend = 0.17). Findings were similar by stage and grade of prostate cancer. The results from this large prospective study suggest that intake of calcium or some related component contained in dairy foods is associated with increased prostate cancer risk.  相似文献   

6.
Objectives: Dairy products consistently have been associated with an increased risk of prostate cancer, yet the mechanism of this relationship remains unknown. Recent hypotheses propose that 1,25 dihydroxyvitamin D (1,25 D) is protective for prostate cancer. One study in the United States found that calcium consumption, which can lower circulating 1,25 D, was associated with higher risk of advanced prostate cancer, and we sought to address this hypothesis in a distinct population.Methods: We analyzed data from a population-based case- control study of prostate cancer conducted in Örebro, Sweden, with 526 cases and 536 controls. Using unconditional logistic regression models, we examined the relationship of dairy products, dietary calcium, phosphorous, and vitamin D with risk of total, extraprostatic, and metastatic prostate cancer.Results: Calcium intake was an independent predictor of prostate cancer (relative risk (RR)=1.91, 95 percent confidence interval (CI) 1.23-2.97 for intake 1183 vs. <825mg/day), especially for metastatic tumors (RR=2.64, 95 percent CI 1.24-5.61), controlling for age, family history of prostate cancer, smoking, and total energy and phosphorous intakes. High consumption of dairy products was associated with a 50 percent increased risk of prostate cancer.Conclusions: Our results support the hypothesis that high calcium intake may increase risk of prostate cancer, and this relation may underlie previously observed associations between dairy products and prostate cancer.  相似文献   

7.
Objective: Epidemiologic studies on calcium, vitamin D and colon cancer are inconsistent, whereas experimental studies more regularly show a protective effect. To evaluate potential sources of inconsistencies, data from a large case–control study were analyzed, stratifying on potential effect modifiers. Methods: Data were collected by certified interviewers in Northern California, Utah and Minnesota. Analyses included 1993 incident colon cancer cases and 2410 population-based controls. Multivariate logistic regression models included age, sex, BMI, family history, physical activity, intake of energy, dietary fiber, aspirin and NSAIDs. Results: Dietary calcium was inversely associated with colon cancer risk in men (OR highest vs lowest quintile = 0.6, 95% CI = 0.5–0.9) and women (OR = 0.6, 95% CI = 0.4–0.9). No statistically significant associations were observed for dietary vitamin D or sunshine exposure. Consumption of total low-fat dairy products was associated with a statistically significantly decreased risk in men and women (ORs highest vs lowest category of intake = 0.8 and 0.7 respectively). Calcium supplement use was inversely associated with risk in both sexes (ORs use vs non-use = 0.8). Vitamin D supplements were inversely associated with risk in men (OR = 0.5) and women (OR = 0.6) but confidence limits included 1.0. Conclusions: These data provide additional support of an inverse association between high levels of calcium intake and colon cancer risk.  相似文献   

8.
9.
In a prospective study of 10,011 men with 815 prostate cancer cases, despite plausible biological mechanisms, neither increasing intake levels of dairy products nor calcium from dairy products (P trend; 0.23 and 0.64, respectively), or calcium supplements was associated with prostate cancer risk (relative risk, 1.05; 95% confidence interval, 0.84-1.31).  相似文献   

10.
Cyclin D1 A870G polymorphism and the risk of colorectal cancer and adenoma   总被引:3,自引:0,他引:3  
Cyclin D1 (CCND1) plays a key role in cell cycle control, particularly in the transition from G1 to S phase, which is regulated by cyclin-dependent kinases. A common adenine to guanine polymorphism (A870G) in the CCND1 gene has been associated with a longer-life protein and an increased risk of colorectal cancer and adenoma in some studies. Among subjects with hereditary nonpolyposis colorectal cancer, the A870G polymorphism has also been associated with a younger age of onset of colorectal cancer. We analysed 181 colorectal cancer cases and 475 matched controls and 524 adenoma cases and 517 matched controls within women in the Nurses' Health Study (NHS) cohort, 171 colorectal cancer cases and 347 matched controls and 372 adenoma cases and 712 matched controls nested within men in the Health Professionals' Follow-Up Study (HPFS) cohort, and 258 colorectal cancer cases and 415 matched controls within men in the Physicians' Health Study (PHS) cohort to assess the risk associated with the CCND1 A870G genotype. Moreover, we assessed whether CCND1 genotype modified the effect of a sporadic (nonsyndromic) family history of colorectal cancer as well as the effect of other dietary and lifestyle risk factors for colorectal cancer and adenoma. In all cohorts combined, the CCND1 polymorphism did not show statistically significant associations to risk of colorectal cancer (odds ratio (OR) for A allele carriers, 1.04; 95% confidence interval (95% CI), 0.82-1.32) or adenoma (OR, 0.96; 95% CI, 0.79-1.18). The CCND1 A870G genotype was associated with a modest, although nonsignificantly elevated risk of colorectal cancer (OR, 1.59; 95% CI, 0.98-2.57) in women. In contrast, the polymorphism was not associated with increased risk of adenoma in either men or women. Among participants with the A870G genotype, a family history of colorectal cancer conferred a substantially greater risk of colorectal cancer in the women (P for interaction=0.06) and adenoma in the men (P for interaction=0.02). Current postmenopausal hormone (PMH) use was associated with a significant reduction in the risk of colorectal cancer and adenoma among women with the A870G genotype, whereas there was no effect of PMH use among those with the GG genotype. The CCND1 polymorphism appeared to confer a modest elevation in the risk of colorectal cancer among women. Moreover, the A870G genotype may enhance the protective effect of postmenopausal oestrogen use on the development of colorectal neoplasia.  相似文献   

11.
Serum 25-hydroxyvitamin D (25(OH)D) has been demonstrated to be associated with risk of colorectal cancer (CRC). However, it remains unclear whether this association was modified by vitamin D-related polymorphisms. We evaluated association of serum 25(OH)D concentration with CRC risk among 403 170 participants from UK Biobank Project. Two variants of vitamin D binding protein (VDBP), rs4588 and rs7041, were included to estimate the binding affinity of 25(OH)D to VDBP, and three variants of vitamin D receptor (VDR), rs11568820, rs2228570 and rs1544410, which may influence VDR activity, were also investigated. Multivariable Cox proportional hazards regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). During 4 957 677 person-years of follow-up, 5053 incident CRC cases were documented. Higher serum 25(OH)D concentrations were significantly associated with lower CRC incidence in a dose-response manner, with HR (95% CIs) being 0.94 (0.91-0.97) per 1 SD increment of serum 25(OH)D level (Ptrend < .001). When separated by anatomic site, we observed a significant association between higher 25(OH)D and lower incidence of colon cancer (Ptrend < .001), but not rectal cancer (Ptrend = .880). The inverse associations between 25(OH)D level and CRC risk were demonstrated in almost all individuals carrying different GC or VDR genotypes, except for those with rs1544410 TT or rs4588 TT genotypes. There was no significant interaction between any single variant, or haplotypes of GC or VDR, and 25(OH)D level. Our findings suggest the potential benefits of maintaining adequate vitamin D for CRC prevention, particularly for tumors from colon.  相似文献   

12.
13.

Background:

In an earlier study, a 25-hydroxyvitamin D3 (25(OH)D) score calculated from known predictors of vitamin D status significantly predicted plasma levels of 25(OH)D and the risk of colorectal cancer, but the influence of the 25(OH)D score on survival after diagnosis is unknown.

Materials and methods:

We prospectively examined the influence of post-diagnosis predicted 25(OH)D levels on mortality among 1017 participants in the Nurses'' Health Study and Health Professionals Follow-Up Study who were diagnosed with colorectal cancer from 1986 to 2004. Colorectal cancer-specific and overall mortality according to quintiles of predicted 25(OH)D levels were assessed. Cox proportional hazards models were used to calculate hazard ratios (HRs) adjusted for other risk factors of survival.

Results:

Higher predicted 25(OH)D levels were associated with a significant reduction in colorectal cancer-specific (P trend=0.02) and overall mortality (P trend=0.002). Compared with levels in the lowest quintile, participants with predicted 25(OH)D levels in the highest quintile had an adjusted HR of 0.50 (95% CI, 0.26–0.95) for cancer-specific mortality and 0.62 (95% CI, 0.42–0.93) for overall mortality.

Conclusion:

Higher predicted 25(OH)D levels after a diagnosis of colorectal cancer may be associated with improved survival. Further study of the vitamin D pathway in colorectal cancer is warranted.  相似文献   

14.
Although calcium and vitamin-D intake were consistently shown to be inversely associated with colorectal cancer risk in several large prospective studies and protective against adenoma and cancer in multiple randomized trials, the Women's Health Initiative (WHI) of calcium and low-dose vitamin-D supplementation trial found no overall effects on colorectal cancer. However, the previous report did not recognize an important biologic interaction with estrogen therapy. We investigated the treatment interaction of estrogen with calcium and vitamin-D on risk of colorectal cancer via a reanalysis of primary data results from the WHI calcium and vitamin-D supplementation trial (1,000 mg elemental calcium, 400 IU of vitamin-D3, or placebo), reanalyzing results from women concurrently randomized to estrogen interventions and placebo. Results indicate that concurrent estrogen therapy was a strong effect modifier of calcium and vitamin-D supplementation on colorectal cancer risk. While calcium plus vitamin-D supplementation among women concurrently assigned to estrogen therapies suggested increased risk (Hazard Ratio = 1.50, 95% CI: 0.96-2.33), among women concurrently assigned to placebos arms of the estrogen trials, calcium plus vitamin-D indicated suggestive benefits (HR = 0.71, 95% CI: 0.46-1.09) (p-for-estrogen-interaction = 0.018). Consistent interaction was also found by reported estrogen use (p interaction = 0.037). Results indicate contrasting effects of calcium and vitamin-D by concurrent estrogen therapy on colorectal cancer risk. Although further clinical and mechanistic studies are warranted, the potential clinical implications of the apparent interaction of estrogen therapy with calcium and vitamin-D supplementation should be recognized. Important biological mechanisms related to the key membrane receptor megalin and estrogen-dependent protein calbindin are discussed.  相似文献   

15.
16.
Coffee is a commonly consumed beverage which contains several potential anticarcinogenic and chemopreventive compounds, and has been hypothesized to have protective effects in colorectal neoplasia. However, the limited available data on coffee consumption in relation to colorectal adenoma (CRA), a precursor lesion to most colorectal cancers, remain largely inconsistent. In this study, we evaluated the association of coffee intake with the risk of CRA in a middle‐aged Japanese population. Study subjects were selected from examinees who underwent total colonoscopy as part of a cancer screening program and responded to self‐administered dietary and lifestyle questionnaires. A total of 738 patients with adenoma and 697 controls were included in the study. Coffee intake was assessed with a food frequency questionnaire, and divided into quartiles based on the distribution among controls. Unconditional logistic regression models were used to estimate odds ratio (OR) and 95% confidence interval (CI) of CRA, with adjustment for potential confounding factors. High coffee consumption was associated with a reduced risk of CRA, with a multivariate‐adjusted OR for the highest versus lowest quartile of coffee intake of 0.67 (95% CI = 0.48–0.93; ptrend = 0.02). The inverse association of coffee intake was limited to proximal (OR = 0.64; 95%CI = 0.44–0.95; ptrend = 0.04) and distal colon adenoma (OR = 0.62; 95%CI = 0.39–0.99; ptrend = 0.06), and appeared to be more evident with small (OR = 0.68; 95%CI = 0.49–0.96; ptrend = 0.04) and single adenomas (OR = 0.65; 95%CI = 0.44–0.95; ptrend = 0.02). Green tea intake was not found to be associated with CRA risk. This study provides support for the protective effect of coffee drinking on colon adenomas, a precursor of colon cancer.  相似文献   

17.
18.
A reanalysis of the Women's Health Initiative (WHI) randomized clinical trial found a significant interaction between supplementation with vitamin D/calcium and estrogen therapy and the risk of colorectal cancer risk, with reduced risks from supplementation limited to the placebo arms of the estrogen trials. To explore whether the vitamin D effects are modified by estrogen therapy, we report a largely cross‐sectional, analysis of the association between sun exposure, which is an important vitamin D source, and colorectal cancer risk among postmenopausal women in the U.S. Radiologic Technologists study. Among 21,695 participants, there were a total of 108 cases. Sun exposure was based on time outdoors and on ambient ultraviolet radiation (UV) exposure based on residence linked to erythemal exposures derived from the Total Ozone Mapping Spectrometer database. Although there was no relationship between outdoor time or ambient UV measure and colorectal cancer risk in current hormone replacement therapy (HRT) users, in never/past HRT users, there was an inverse association with higher ambient UV exposure, RR for highest vs. lowest tertile = 0.40; 95% CI 017, 0.93; p for trend = 0.04. Non‐significant lower risks were also associated with higher levels of outdoor time (≥3.5 hr/week) in never/past HRT users. The interaction between both indicators of sun exposure and HRT and CRC risk was not significant. These data, although exploratory, are consistent with evidence from the WHI suggesting a decrease in colorectal cancer risk may be associated with vitamin D exposure among postmenopausal women who are not taking HRT, but not among current HRT users.  相似文献   

19.
Lignans and proanthocyanidins are plant polyphenols that have shown protective properties against colorectal neoplasms in some human studies. Using logistic regression, we estimated odds ratios (ORs) and 95% confidence intervals (CIs) to prospectively evaluate the association between lignan and proanthocyanidin intake, estimated from databases linked to a food frequency questionnaire, and adenoma recurrence in 1,859 participants of the Polyp Prevention Trial. Overall, individual or total lignans or proanthocyanidins were not associated with colorectal adenoma recurrence. However, in sex-specific analyses, total lignan intake was positively associated with any adenoma recurrence in women (highest vs. lowest lignan intake quartile OR = 2.07, 95% CI: 1.22-3.52, p trend = 0.004) but not in men (p interaction = 0.04). To conclude, dietary lignan and proanthocyanidin consumption were not generally related to colorectal adenoma recurrence; however, high lignan intake may increase the risk of adenoma recurrence in women.  相似文献   

20.
A protective effect of calcium against colorectal cancer has been described in Anglo-Saxon but not in Latin communities, and no such effect has been observed regarding adenomas. We investigated the relationship between calcium, dairy products and the adenoma-carcinoma sequence in a French region by comparing small adenoma ( < 10 mm, n = 154), large adenoma (n = 208) and polyp-free (n = 426) subjects, and cancer cases (n = 171) with population controls (n = 309). There was no protective effect of calcium against colorectal tumours except for low fat calcium and large adenomas in men (OR for highest quintile = 0.3, P for trend = 0.06). There was even a trend towards an increased risk of cancer with dairy calcium in men and non-dairy calcium in women. Vitamin D was inversely related to the risk of small adenomas in women (OR for highest quintile = 0.4, P for trend = 0.04). Regarding dairy products, only consumption of yoghurt displayed an inverse relationship with risk of large adenomas, in both men and women. These data failed to demonstrate a protective effect of calcium against colorectal carcinogenesis. They suggest that the type of dairy product might be the important factor with regard to prevention of colorectal tumours.  相似文献   

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