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Sponsors and Collaborators: |
Emory University National Institutes of Health (NIH) |
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Information provided by: | Emory University |
ClinicalTrials.gov Identifier: | NCT00208793 |
The purpose of this study is to test whether calcium and/or vitamin D supplementation favorably affects a set of biomarkers of risk for colon cancer in persons who are at higher than average risk for colon cancer (ie, have already undergone the removal of adenomatous polyps, which are known to be precursors to developing colon cancer).
Condition | Intervention | Phase |
---|---|---|
Colonic Polyps Adenomatous Polyps |
Drug: Calcium (as calcium carbonate) Drug: Vitamin D Drug: Calcium and Vitamin D in combination Drug: Placebo |
Phase II |
Study Type: | Interventional |
Study Design: | Prevention, Randomized, Double-Blind, Placebo Control, Factorial Assignment, Efficacy Study |
Official Title: | Calcium, Vitamin D, and Colon Cancer Risk Biomarkers |
Estimated Enrollment: | 88 |
Study Start Date: | May 2005 |
Estimated Study Completion Date: | September 2006 |
There is strong biologic plausibility and animal experimental evidence for protection against colorectal cancer by calcium and vitamin D, calcium significantly reduced adenoma recurrence in a large clinical trial in humans (yet the previously reported observational evidence, although generally supportive, is inconsistent), and the observational literature strongly supports protection from vitamin D. A close physiological relationship between calcium and vitamin D has long been known. Yet, other than a possible reduction of colorectal epithelial cell proliferation by calcium, the effects of calcium and vitamin D, individually or jointly, on the normal human colorectal epithelium remain unknown. There have been no clinical trials involving vitamin D individually or jointly with calcium related to colorectal cancer chemoprevention in humans. There are currently no generally accepted pre-neoplastic biomarkers of risk for colorectal cancer other than the possible exception of proliferation markers that, at best, have limited usefulness as individual markers. Based on recent advances in understanding the molecular basis of colorectal cancer, we developed a panel of newer, plausible, reliable, immunohistochemically detected biomarkers that provides molecular phenotyping of the normal appearing colorectal epithelium: 1) inflammation (COX-2), 2) the expression of genes involved in the normal structure and function of the colorectal epithelium that have been found to be altered early in the two major colorectal carcinogenesis pathways (APC, MSH2, MLH1), and 3) a more complete picture of the cell cycle events in colorectal epithelial crypt cells (short and long-term proliferation: MIB-1 and telomerase; differentiation: p21; apoptosis inhibition and promotion: bcl-2, bax, and bak) that has not yet been tested in a chemoprevention trial.
To address these needs, we will conduct a preliminary, randomized, double-blind, placebo-controlled, 2 x 2 factorial chemoprevention trial (n = 88) of calcium 2,000 mg/day and vitamin D3 800 IU/day, alone and in combination vs placebo over 6 months in patients with recent removal of sporadic adenomatous colorectal polyps, to investigate their effects on the individual components and aggregate profile of our colorectal cancer risk biomarker panel. We will also examine study results stratified by NSAID use and Bsm I vitamin D receptor genotypes. The preliminary estimates of treatment effect sizes and variabilities will be used to refine the biomarker panel and study design and to calculate the needed sample size for a potential full-scale study.
We assert that using biological measurements of risk, as they have for ischemic heart disease, will result in a decline in colorectal cancer incidence and mortality. The proposed project is borne of this vision, and has intertwined missions of exploring the efficacy of two plausible and evidentially well-supported dietary agents, calcium and vitamin D, on the modulation of a plausible panel of molecular phenotypic biomarkers of risk for colorectal neoplasia.
Ages Eligible for Study: | 30 Years to 74 Years |
Genders Eligible for Study: | Both |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
Exclusion Criteria:
United States, Georgia | |
The Emory Clinic, Division of Digestive Diseases | |
Atlanta, Georgia, United States, 30322 |
Principal Investigator: | Roberd M Bostick, MD, MPH | Emory University, Rollins School of Public Health & Winship Cancer Institute |
Study ID Numbers: | 0126-2004, 5 R01 CA104637-02 |
Study First Received: | September 13, 2005 |
Last Updated: | January 12, 2006 |
ClinicalTrials.gov Identifier: | NCT00208793 History of Changes |
Health Authority: | United States: Federal Government |
colonic polyps adenomatous polyps colon cancer prevention dietary supplements |
Pathological Conditions, Anatomical Digestive System Neoplasms Gastrointestinal Diseases Colonic Diseases Colonic Polyps Trace Elements Bone Density Conservation Agents Polyps Calcium Carbonate Intestinal Diseases Intestinal Neoplasms Calcium, Dietary |
Vitamin D Digestive System Diseases Vitamins Gastrointestinal Neoplasms Antacids Micronutrients Adenoma Colonic Neoplasms Adenomatous Polyps Colorectal Neoplasms Neoplasms, Glandular and Epithelial |
Pathological Conditions, Anatomical Molecular Mechanisms of Pharmacological Action Gastrointestinal Diseases Colonic Diseases Physiological Effects of Drugs Polyps Bone Density Conservation Agents Calcium Carbonate Neoplasms by Site Vitamins Micronutrients Adenomatous Polyps Digestive System Neoplasms Neoplasms by Histologic Type Growth Substances |
Colonic Polyps Intestinal Diseases Pharmacologic Actions Intestinal Neoplasms Calcium, Dietary Neoplasms Digestive System Diseases Vitamin D Intestinal Polyps Gastrointestinal Neoplasms Antacids Colonic Neoplasms Adenoma Colorectal Neoplasms Neoplasms, Glandular and Epithelial |