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(PHO-0554) To Determine the Effect of Vitamin D and Calcium on Genes in the colon

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High vs Low Calcium Intake in the Presence of High Vitamin D: Effect on Gene Expression in the Colon (PHO-0554)

Principal Investigator:
Peter R. Holt M.D.


Contact Information:
Elizabeth Londono
Rockefeller University
1230 York Avenue
New York, NY 10021
Telephone: 1800-RU-CARES
Enrollment Status:
Closed to Enrollment

Brief Summary of Protocol:
We are involved in a research program to understand how vitamin D and calcium in the diet or as supplements may lower the risk of colorectal polyps and cancer. To that end, we are conducting a study of vitamin D supplementation in which volunteer subjects are provided a Western style diet for 2 separate 4 week periods at the Rockefeller University Hospital. During one of these 4 week in patient periods they receive calcium supplement and during the other 4 week inpatient period they receive a placebo tablet. We determine changes within the colon as a result of supplementing the vitamin D in the presents of high and low calcium. A more detailed description of the study is provided below.

Detailed Description of Protocol:
Study subjects participate for about 3 months. During this time, there is one outpatient visit, a 4 week inpatient period, a 4 week outpatient period known as a wash out period and finally another 4 week inpatient period. During the inpatient periods The Rockefeller University Hospital becomes your home the subject must sleep here every night and consume all the food provided. During the screening visit blood and urine samples will be taken and an EKC (electrocardiogram) and a complete physical exam will be done. After enrollment into the study, the first 4 week inpatient period begins. You may continue to go to work or do other activities as long as you eat the diet provided and sleep at the Rockefeller University Hospital. You must eat everything that we give you and you may not substitute or supplement the diet in any way. During each 4 week stay at The Rockefeller University Hospital, there will be three flexible sigmoidoscopies done and biopsies taken of the mucosal lining of the colorectum. This procedure is painless and takes about 5 minutes. In addition, blood samples will be taken every few days for follow-up and research, two 24 hour urine samples will be done on separate days during the hospitalization. Vital signs are measured every day and your weight will be measured three times per week. During the four week wash out period, the subject will return to their home, go about their normal activities and consume their normal diet. The subject will return to The Rockefeller University Hospital for the second 4 week inpatient period. The procedures and laboratory tests are the same during the second inpatient period. The study concludes with the subjects discharge from the RUH. Profile:
Healthy volunteer

What specifically makes a person eligible for the study?
You may be eligible to enter this study:

You have a history of colorectal adenomatous polyps.

And /or

You have a family history of colorectal adenomatous polyps or colon cancer


48-72 years

Children permitted to participate:

Potential Benefits.....
Comprehensive physical exam

Total compensation amount is $3200

$250 per week for the 8 week inpatient ($2000)

$200 per biopsy for the 6 biopsies ($1200)