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1.
JAMA Dermatol ; 159(10): 1076-1084, 2023 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-37647056

RESUMEN

Importance: The gut microbiome modulates the immune system and responses to immunotherapy in patients with late-stage melanoma. It is unknown whether fecal microbiota profiles differ between healthy individuals and patients with melanoma or if microbiota profiles differ among patients with different stages of melanoma. Defining gut microbiota profiles in individuals without melanoma and those with early-stage and late-stage melanoma may reveal features associated with disease progression. Objective: To characterize and compare gut microbiota profiles between healthy volunteers and patients with melanoma and between patients with early-stage and late-stage melanoma. Design, Setting, and Participants: This single-site case-control study took place at an academic comprehensive cancer center. Fecal samples were collected from systemic treatment-naive patients with stage I to IV melanoma from June 1, 2015, to January 31, 2019, and from healthy volunteers from June 1, 2021, to January 31, 2022. Patients were followed up for disease recurrence until November 30, 2021. Main Outcomes and Measures: Fecal microbiota was profiled by 16S ribosomal RNA sequencing. Clinical and pathologic characteristics, treatment, and disease recurrence were extracted from electronic medical records. Fecal microbiome diversity, taxonomic profiles and inferred functional profiles were compared between groups. Results: A total of 228 participants were enrolled (126 men [55.3%]; median age, 59 [range, 21-90] years), including 49 volunteers without melanoma, 38 patients with early-stage melanoma (29 with stage I or melanoma in situ and 9 with stage II), and 141 with late-stage melanoma (66 with stage III and 75 with stage IV). Community differences were observed between patients with melanoma and volunteers. Patients with melanoma had a higher relative abundance of Fusobacterium compared with controls on univariate analysis (0.19% vs 0.003%; P < .001), but this association was attenuated when adjusted for covariates (log2 fold change of 5.18 vs controls; P = .09). Microbiomes were distinct between patients with early-stage and late-stage melanoma. Early-stage melanoma had a higher alpha diversity (Inverse Simpson Index 14.6 [IQR, 9.8-23.0] vs 10.8 [IQR, 7.2-16.8]; P = .003), and a higher abundance of the genus Roseburia on univariate analysis (2.4% vs 1.2%; P < .001) though statistical significance was lost with covariate adjustment (log2 fold change of 0.86 vs controls; P = .13). Multiple functional pathways were differentially enriched between groups. No associations were observed between the microbial taxa and disease recurrence in patients with stage III melanoma treated with adjuvant immunotherapy. Conclusions and Relevance: The findings of this case-control study suggest that fecal microbiota profiles were significantly different among patients with melanoma and controls and between patients with early-stage and late-stage melanoma. Prospective investigations of the gut microbiome and changes that occur with disease progression may identify future microbial targets for intervention.


Asunto(s)
Microbioma Gastrointestinal , Melanoma , Masculino , Humanos , Persona de Mediana Edad , Microbioma Gastrointestinal/inmunología , Estudios Prospectivos , Estudios de Casos y Controles , Progresión de la Enfermedad , Melanoma Cutáneo Maligno
2.
Eur Urol Oncol ; 6(3): 282-288, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35995710

RESUMEN

BACKGROUND: Coffee intake may lower prostate cancer risk and progression, but postdiagnosis outcomes by caffeine metabolism genotype are not well characterized. OBJECTIVE: To evaluate associations between coffee intake, caffeine metabolism genotype, and survival in a large, multicenter study of men with prostate cancer. DESIGN, SETTING, AND PARTICIPANTS: Data from The PRACTICAL Consortium database for 5727 men with prostate cancer from seven US, Australian, and European studies were included. The cases included had data available for the CYP1A2 -163C>A rs762551 single-nucleotide variant associated with caffeine metabolism, coffee intake, and >6 mo of follow-up. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Multivariable-adjusted Cox proportional hazards models across pooled patient-level data were used to compare the effect of coffee intake (categorized as low [reference], high, or none/very low) in relation to overall survival (OS) and prostate cancer-specific survival (PCSS), with stratified analyses conducted by clinical disease risk and genotype. RESULTS AND LIMITATIONS: High coffee intake appeared to be associated with longer PCSS (hazard ratio [HR] 0.85, 95% confidence interval [CI] 0.68-1.08; p = 0.18) and OS (HR 0.90, 95% CI 0.77-1.07; p = 0.24), although results were not statistically significant. In the group with clinically localized disease, high coffee intake was associated with longer PCSS (HR 0.66, 95% CI 0.44-0.98; p = 0.040), with comparable results for the group with advanced disease (HR 0.92, 95% CI 0.69-1.23; p = 0.6). High coffee intake was associated with longer PCSS among men with the CYP1A2 AA (HR 0.67, 95% CI 0.49-0.93; p = 0.017) but not the AC/CC genotype (p = 0.8); an interaction was detected (p = 0.042). No associations with OS were observed in subgroup analyses (p > 0.05). Limitations include the nominal statistical significance and residual confounding. CONCLUSIONS: Coffee intake was associated with longer PCSS among men with a CYP1A2 -163AA (*1F/*1F) genotype, a finding that will require further replication. PATIENT SUMMARY: It is likely that coffee intake is associated with longer prostate cancer-specific survival in certain groups, but more research is needed to fully understand which men may benefit and why.


Asunto(s)
Cafeína , Neoplasias de la Próstata , Masculino , Humanos , Cafeína/metabolismo , Café , Citocromo P-450 CYP1A2/genética , Citocromo P-450 CYP1A2/metabolismo , Factores de Riesgo , Australia , Genotipo , Neoplasias de la Próstata/genética
3.
J Nutr ; 149(8): 1443-1450, 2019 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-31100111

RESUMEN

BACKGROUND: Previous studies have found that meat-derived mutagens increase, and vitamin C or E decrease, the risk of pancreatic cancer. OBJECTIVE: The aim of this study was to determine whether intake of vitamin C or E modulates the association between meat-derived mutagen exposure and risk of pancreatic cancer. DESIGN: We conducted a case-control study in 1321 patients with pathologically confirmed pancreatic ductal adenocarcinoma (PDAC) and 1061 healthy controls (aged 28-88 y). Cases and controls were frequency-matched by age, sex, and race/ethnicity. Mutagen intake was assessed using a meat preparation questionnaire. Intakes of vitamin C, E, and other dietary components were assessed via a food-frequency questionnaire in a subset of 811 cases and 818 controls. ORs and 95% CIs were estimated in multivariable-adjusted logistic regression models. RESULTS: The risk of PDAC was not associated with meat intake but was associated with consumption of well-done grilled or barbecued chicken (OR: 1.57; 95% CI: 1.18, 2.09; P = 0.001). Intake of 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline was associated with increased PDAC risk (Ptrend = 0.047). Participants in the highest, as compared with the lowest, quintile of 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline (PhIP) intake experienced a 38% increased risk of PDAC (95% CI: 1.00, 1.90; P = 0.048). Intakes of total vitamin C or E from food and supplements or from supplements alone were each inversely associated with PDAC risk. Stratified analyses showed differential associations for PhIP intake and PDAC risk, such that risk increased among individuals with lower intake of vitamin C or E and decreased among those with higher vitamin intake. Significant interactions of dietary vitamin C, dietary vitamin E, and total vitamin E with PhIP intake were detected (Pinteraction = 0.023, <0.001, and 0.013, respectively). CONCLUSIONS: Consistent with experimental evidence, this study of 811 cases and 818 controls has shown that high intake of dietary vitamin C or E mitigates the risk of PhIP-related PDAC.


Asunto(s)
Ácido Ascórbico/administración & dosificación , Carcinoma Ductal Pancreático/prevención & control , Exposición Dietética , Carne , Mutágenos/toxicidad , Neoplasias Pancreáticas/prevención & control , Vitamina E/administración & dosificación , Anciano , Carcinoma Ductal Pancreático/epidemiología , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/epidemiología , Factores de Riesgo
4.
J Urol ; 201(2): 308-314, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30179617

RESUMEN

PURPOSE: Active surveillance is increasingly used as a management strategy for localized prostate cancer. Coffee intake has been associated with a lower prostate cancer incidence. We assessed whether coffee was associated with disease progression in men on active surveillance. MATERIALS AND METHODS: A total of 411 patients with newly diagnosed Gleason score 6 or 7 prostate cancer were enrolled on a prospective active surveillance protocol for at least 6 months and completed a baseline dietary assessment. The active surveillance protocol included a biennial monitoring regimen with disease progression defined as an increase in the Gleason score. Cox proportional hazards models were used to evaluate associations of coffee intake with progression-free survival. We also evaluated patient genotype in the caffeine metabolism related single nucleotide polymorphism rs762551. RESULTS: Median followup was 36 months (range 6 to 126) and the Gleason score progressed in 76 of the 411 patients (18.5%). Compared to 0 cups per day, in the multivariable model adjusting for prostate specific antigen, patient age and tumor length, less than 1 cup (HR 0.85, 95% CI 0.40-1.71), 1 to 1.9 cups (HR 0.64, 95% CI 0.29-1.43), 2 to 3.9 cups (HR 0.71, 95% CI 0.35-1.47) and 4 cups or more (HR 1.67, 95% CI 0.81-3.45) were not significantly associated with progression-free survival (p for nonlinearity = 0.01). Patients with low/moderate coffee intake and the AA fast caffeine metabolizer genotype were less likely to experience grade progression than nonconsumers (HR 0.36, 95% CI 0.15-0.88, p = 0.03). CONCLUSIONS: Low to moderate coffee intake appears safe in men on active surveillance of localized prostate cancer. Further work is needed to determine whether high consumption is associated with shorter progression-free survival in sensitive groups.


Asunto(s)
Cafeína/metabolismo , Café/efectos adversos , Citocromo P-450 CYP1A2/genética , Neoplasias de la Próstata/mortalidad , Espera Vigilante , Anciano , Cafeína/efectos adversos , Citocromo P-450 CYP1A2/metabolismo , Progresión de la Enfermedad , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Supervivencia sin Progresión , Estudios Prospectivos , Próstata/patología , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Factores de Riesgo , Encuestas y Cuestionarios/estadística & datos numéricos
5.
Mol Carcinog ; 54(4): 270-80, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24166893

RESUMEN

Transforming growth factor alpha (TGFα) and TGFß1 are growth-promoting and -inhibiting autocrine/paracrine growth factors, respectively, that may (1) affect risk for colorectal cancer and (2) be modifiable by anti-proliferative exposures. The effects of supplemental calcium and vitamin D3 on these two markers in the normal-appearing colorectal mucosa in humans are unknown. We conducted a pilot, randomized, double-blind, placebo-controlled, 2 × 2 factorial clinical trial (n = 92; 23/treatment group) of calcium 2 g and/or vitamin D3 800 IU/d versus placebo over 6 mo. TGFα and TGFß1 expression was measured in biopsies of normal-appearing rectal mucosa using automated immunohistochemistry and quantitative image analysis at baseline and 6-mo follow-up. In the calcium, vitamin D3 , and calcium plus vitamin D3 groups relative to the placebo group (1) the mean overall expression of TGFß1 increased by 14% (P= 0.25), 19% (P = 0.17), and 22% (P = 0.09); (2) the ratio of TGFα expression in the upper 40% (differentiation zone) to that in the lower 60 (proliferation zone) of the crypts decreased by 34% (P = 0.11), 31% (P = 0.22), and 26% (P = 0.33); and (3) the TGFα/TGFß1 ratio in the upper 40% of the crypts decreased by 28% (P = 0.09), 14% (P = 0.41), and 22% (P = 0.24), respectively. These preliminary results, although not statistically significant, suggest that supplemental calcium and vitamin D3 may increase TGFß1 expression and shift TGFα expression downward from the differentiation to the proliferation zone in the crypts in the normal-appearing colorectal mucosa of sporadic colorectal adenoma patients, and support further investigation in a larger clinical trial.


Asunto(s)
Adenoma/patología , Anticarcinógenos/uso terapéutico , Calcio de la Dieta/uso terapéutico , Colecalciferol/uso terapéutico , Neoplasias Colorrectales/patología , Mucosa Intestinal/patología , Factores de Crecimiento Transformadores/análisis , Adenoma/prevención & control , Anciano , Neoplasias Colorrectales/prevención & control , Suplementos Dietéticos/análisis , Método Doble Ciego , Femenino , Humanos , Inmunohistoquímica , Mucosa Intestinal/efectos de los fármacos , Masculino , Persona de Mediana Edad , Recto/efectos de los fármacos , Recto/patología , Factor de Crecimiento Transformador alfa/análisis , Factor de Crecimiento Transformador beta1/análisis
6.
Am J Clin Nutr ; 96(2): 374-81, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22695871

RESUMEN

BACKGROUND: Coffee and tea are widely consumed globally and are rich sources of potential chemopreventive compounds. Epidemiologic data for coffee and tea intakes in relation to colorectal cancer remain unclear. Despite differences in gut physiology, few studies have conducted investigations by anatomic subsites. OBJECTIVE: We evaluated coffee and tea intakes (caffeinated and decaffeinated) in relation to colon (proximal and distal) and rectal cancers. DESIGN: The NIH-AARP Diet and Health Study included 489,706 men and women who completed a baseline (1995-1996) self-administered questionnaire of demographics, diet, and lifestyle. Over a median of 10.5 y of follow-up, we identified 2863 proximal colon, 1993 distal colon, and 1874 rectal cancers. Multivariable HRs and 95% CIs were estimated by using Cox regression. RESULTS: Approximately 16% of participants drank ≥4 cups coffee/d. Compared with nondrinkers, drinkers of 4-5 cups coffee/d (HR: 0.85; 95% CI: 0.75, 0.96) and ≥6 cups coffee/d (HR: 0.74; 95% CI: 0.61, 0.89; P-trend < 0.001) had a lower risk of colon cancer, particularly of proximal tumors (HR for ≥6 cups/d: 0.62; 95% CI: 0.49, 0.81; P-trend < 0.0001). Results were similar to those overall for drinkers of predominantly caffeinated coffee. Although individual HRs were not significant, there was a significant P-trend for both colon and rectal cancers for people who drank predominantly decaffeinated coffee. No associations were observed for tea. CONCLUSIONS: In this large US cohort, coffee was inversely associated with colon cancer, particularly proximal tumors. Additional investigations of coffee intake and its components in the prevention of colorectal cancer by subsites are warranted. The NIH-AARP Diet and Health Study was registered at clinicaltrials.gov as NCT00340015.


Asunto(s)
Bebidas/análisis , Cafeína/administración & dosificación , Café/química , Neoplasias Colorrectales/prevención & control , Conducta Alimentaria , Té/química , Neoplasias Colorrectales/etiología , Neoplasias Colorrectales/fisiopatología , Dieta , Femenino , Estudios de Seguimiento , Humanos , Estilo de Vida , Masculino , Persona de Mediana Edad , Análisis Multivariante , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Medición de Riesgo , Factores de Riesgo , Encuestas y Cuestionarios
7.
Cancer Res ; 71(2): 413-23, 2011 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-21084270

RESUMEN

In cancer cell lines and rodent models, calcium and vitamin D favorably modulate cell proliferation, differentiation, and apoptosis in colonic epithelia. These effects may be modulated by local expression of the calcium receptor (CaR), the vitamin D receptor (VDR), and the P450 cytochromes, CYP27B1 and CYP24A1; however, they have yet to be investigated in humans. To address this gap, we conducted a randomized, double-blinded, placebo-controlled 2×2 factorial clinical trial. Patients with at least one pathology-confirmed colorectal adenoma were treated with 2 g/d elemental calcium and/or 800 IU/d vitamin D3 versus placebo over 6 months (n=92; 23 per group). CaR, VDR, CYP27B1, and CYP24A1 expression and distribution in biopsies of normal appearing rectal mucosa were detected by standardized, automated immunohistochemistry and quantified by image analysis. In the calcium-supplemented group, CaR expression increased 27% (P=0.03) and CYP24A1 expression decreased 21% (P=0.79). In the vitamin D3-supplemented group, CaR expression increased 39% (P=0.01) and CYP27B1 expression increased 159% (P=0.06). In patients supplemented with both calcium and vitamin D3, VDR expression increased 19% (P=0.13) and CaR expression increased 24% (P=0.05). These results provide mechanistic support for further investigation of calcium and vitamin D3 as chemopreventive agents against colorectal neoplasms, and CaR, VDR, CYP27B1, and CYP24A1 as modifiable, preneoplastic risk biomarkers for colorectal neoplasms.


Asunto(s)
Adenoma/tratamiento farmacológico , Biomarcadores de Tumor/metabolismo , Calcio/administración & dosificación , Colecalciferol/administración & dosificación , Neoplasias Colorrectales/prevención & control , 25-Hidroxivitamina D3 1-alfa-Hidroxilasa/biosíntesis , Adenoma/sangre , Adenoma/metabolismo , Calcio/metabolismo , Neoplasias Colorrectales/sangre , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/metabolismo , Método Doble Ciego , Femenino , Humanos , Inmunohistoquímica , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/metabolismo , Masculino , Persona de Mediana Edad , Proyectos Piloto , Lesiones Precancerosas/sangre , Lesiones Precancerosas/tratamiento farmacológico , Lesiones Precancerosas/metabolismo , Receptores de Calcitriol/biosíntesis , Receptores Sensibles al Calcio/biosíntesis , Esteroide Hidroxilasas/biosíntesis , Vitamina D/análogos & derivados , Vitamina D/sangre , Vitamina D3 24-Hidroxilasa
8.
Cancer Epidemiol Biomarkers Prev ; 19(1): 280-91, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20056649

RESUMEN

The exact antineoplastic effects of calcium and vitamin D(3) in the human colon are unclear. Animal and in vitro studies show that these two agents reduce oxidative stress; however, these findings have never been investigated in humans. To address this, we conducted a pilot, randomized, double-blind, placebo-controlled, 2 x 2 factorial clinical trial to test the effects of calcium and vitamin D(3) on a marker of oxidative DNA damage, 8-hydroxy-2'-deoxyguanosine (8-OH-dG), in the normal colorectal mucosa. Patients (N = 92) with at least one pathology-confirmed colorectal adenoma were treated with 2 g/d calcium and/or 800 IU/d vitamin D(3) versus placebo over 6 months. Overall labeling and colorectal crypt distribution of 8-OH-dG in biopsies of normal-appearing rectal mucosa were detected by standardized automated immunohistochemistry and quantified by image analysis. After 6 months of treatment, 8-OH-dG labeling along the full lengths of colorectal crypts decreased by 22% (P = 0.15) and 25% (P = 0.10) in the calcium and vitamin D(3) groups, respectively, but not in the calcium plus vitamin D(3) group. The estimated treatment effects were strongest among participants with higher baseline colon crypt vitamin D receptor expression (P = 0.05). Overall, these preliminary results indicate that calcium and vitamin D(3) may decrease oxidative DNA damage in the normal human colorectal mucosa, support the hypothesis that 8-OH-dG labeling in colorectal crypts is a treatable oxidative DNA damage biomarker of risk for colorectal neoplasms, and provide support for further investigation of calcium and vitamin D(3) as chemopreventive agents against colorectal neoplasms.


Asunto(s)
Carbonato de Calcio/uso terapéutico , Colecalciferol/uso terapéutico , Daño del ADN/efectos de los fármacos , Desoxiguanosina/análogos & derivados , Mucosa Intestinal/efectos de los fármacos , Neoplasias Intestinales/prevención & control , 8-Hidroxi-2'-Desoxicoguanosina , Adenoma/patología , Adulto , Anciano , Biomarcadores de Tumor/análisis , Calcio de la Dieta/uso terapéutico , Desoxiguanosina/análisis , Suplementos Dietéticos , Método Doble Ciego , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Estrés Oxidativo/efectos de los fármacos , Proyectos Piloto , Lesiones Precancerosas/patología
9.
Cancer Prev Res (Phila) ; 2(3): 213-23, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19258546

RESUMEN

To further clarify and/or develop calcium and vitamin D as chemopreventive agents against colorectal cancer in humans, understand the mechanisms by which these agents reduce risk for the disease, and develop "treatable" biomarkers of risk for colorectal cancer, we conducted a pilot, randomized, double-blind, placebo-controlled, 2 x 2 factorial clinical trial to test the effects of calcium and vitamin D3, alone and in combination on markers of apoptosis, in the normal colorectal mucosa. Ninety-two men and women with at least one pathology-confirmed colorectal adenoma were treated with 2.0 g/d calcium or 800 IU/d vitamin D3, alone or in combination, versus placebo over 6 months. Overall expression and colorectal crypt distributions of Bcl-2 (an apoptosis inhibitor) and Bax (an apoptosis promoter) in biopsies of normal-appearing rectal mucosa were detected by automated immunohistochemistry and quantified by image analysis. After 6 months of treatment, Bax expression along the full lengths of crypts increased 56% (P = 0.02) in the vitamin D group and 33% in both the calcium (P = 0.31) and calcium plus vitamin D (P = 0.36) groups relative to the placebo group. The vitamin D treatment effect was more pronounced in the upper 40%, or differentiation zone, of crypts (80%; P = 0.01). There were no statistically significant treatment effects on Bcl-2 expression. Overall, these preliminary results suggest that calcium and vitamin D, individually or together, may enhance apoptosis in the normal human colorectal epithelium, and the strongest treatment effects may be vitamin D related and in the upper sections of the colorectal crypts.


Asunto(s)
Adenoma/tratamiento farmacológico , Apoptosis , Calcio/uso terapéutico , Colon/patología , Neoplasias Colorrectales/tratamiento farmacológico , Mucosa Intestinal/patología , Vitamina D/uso terapéutico , Adulto , Anciano , Colecalciferol/metabolismo , Suplementos Dietéticos , Método Doble Ciego , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Placebos
10.
Cancer Epidemiol Biomarkers Prev ; 18(2): 516-25, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19190143

RESUMEN

BACKGROUND: omega-6 and omega-3 polyunsaturated fatty acids intakes may play opposing roles in inflammation-driven colorectal carcinogenesis. We examined the relationship of these polyunsaturated fatty acids and the ratio of their intake with colorectal cancer risk in a large U.S. prospective cohort. DESIGN: Participants in the Cancer Prevention Study-II Nutrition Cohort completed a detailed questionnaire on diet, medical history, and lifestyle in 1999. Between 1999 and 2005, 869 incident colorectal cancer cases (452 men and 417 women) were identified among 99,080 participants (43,108 men and 55,972 women). Multivariate-adjusted rate ratios were calculated using Cox proportional hazards models. RESULTS: The ratio of total omega-6 to total omega-3 intake was not associated with colorectal cancer risk in either sex. Contrary to our initial hypothesis, total omega-6 intake was inversely related to colorectal cancer risk in men [multivariate relative risk (95% confidence interval) for highest to lowest quartile, 0.81 (0.61-1.07); P(trend) = 0.07], and alpha-linolenic acid, the primary contributor to total omega-3 intake, was associated with increased risk in women for quartiles 2 through 4 versus the lowest quartile [relative risk (95% confidence interval), 1.50 (1.12-2.01), 1.40 (1.04-1.87), and 1.38 (1.02-1.85), respectively; P(trend) = 0.13]. In women, total omega-6 and marine omega-3 intake appeared to be associated with higher and lower risk, respectively, but associations were attenuated with adjustment for other risk factors. CONCLUSIONS: The ratio of omega-6 to omega-3 intake was not related to colorectal cancer risk in this cohort, which may be due to unexpected findings for the individual components. Differential associations by sex warrant further investigation.


Asunto(s)
Neoplasias Colorrectales/epidemiología , Ácidos Grasos Omega-3/administración & dosificación , Ácidos Grasos Omega-6/administración & dosificación , Anciano , Distribución de Chi-Cuadrado , Registros de Dieta , Femenino , Humanos , Incidencia , Estilo de Vida , Masculino , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Factores de Riesgo , Encuestas y Cuestionarios , Estados Unidos/epidemiología
11.
J Am Coll Nutr ; 28(6): 678-86, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20516268

RESUMEN

OBJECTIVE: Vitamin D supplementation may be required for certain subgroups in the United States in whom status and intake are inadequate, but the impact of various doses, and whether calcium administration jointly or independently influences vitamin D metabolite levels, is unclear. METHODS: In a pilot chemoprevention trial of biomarkers of risk for colorectal adenoma, we measured the impact of vitamin D supplementation and/or calcium supplementation on plasma vitamin D metabolite concentrations. Ninety-two adult men and women living in the southeastern United States were randomized to 800 IU vitamin D(3), 2000 mg elemental calcium, both, or placebo daily for 6 months. We examined vitamin D status at baseline and postintervention and compared the change in plasma 25-hydroxyvitamin D (25(OH)D) and 1,25(OH)(2)D levels by intervention group using general linear models. RESULTS: Eighty-two percent of the study population had insufficient plasma 25(OH)D concentrations (<75 nmol/L) at baseline, with the lowest levels observed among African American participants. Vitamin D supplements, with or without calcium supplementation, raised plasma 25(OH)D concentrations, on average, by 25 to 26 nmol/L. Half of the study participants were classified as having sufficient 25(OH)D status after 6 months of 800 IU of vitamin D(3) daily. Calcium alone did not influence 25(OH)D concentrations. CONCLUSION: In this southeastern U.S. population, half of the study participants receiving 800 IU vitamin D(3) daily had blood 25(OH)D concentrations of

Asunto(s)
Calcio/administración & dosificación , Colecalciferol/administración & dosificación , Suplementos Dietéticos , Vitamina D/análogos & derivados , Anciano , Alelos , Análisis de Varianza , Distribución de Chi-Cuadrado , Método Doble Ciego , Femenino , Genotipo , Georgia , Humanos , Masculino , Cumplimiento de la Medicación , Persona de Mediana Edad , Proyectos Piloto , Polimorfismo de Nucleótido Simple , Receptores de Calcitriol/genética , Encuestas y Cuestionarios , Resultado del Tratamiento , Vitamina D/sangre
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