Vitamin D, Genes and Colorectal Cancer

Study Overview
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Brief Summary
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The aim of this study is to investigate the interaction between intake of vitamin D and polymorphisms in GC and CYP2R1 in relation to risk of colorectal cancer in a Danish prospective cohort study.

Detailed Description
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The association between vitamin D and incidence of colorectal cancer (CRC) has been thoroughly investigated in both observational and experimental studies, but the results are conflicting. Genetic epidemiology is an advantageous alternative to randomized, clinical trials for ethical and economic reasons. The aim of this study is to investigate whether polymorphisms in GC and CYP2R1 that predicts 25-hydroxycholecalciferol (25(OH)D) concentrations after both ultraviolet B radiation and consumption of vitamin D3-fortified bread and milk in Danes are associated with risk of CRC; and further, to examine whether intake of vitamin D through diet and supplementation alter the risk of CRC. Data are retrieved from the Danish prospective Diet, Cancer and Health study encompassing 57,053 persons which were recruited between 1993 to 1997. Between 1994 and 31th December 2009, 1038 CRC cases has been diagnosed. A sub-cohort of 1857 persons has been randomly selected within the full cohort at time of entry into the cohort. The study design is a nested case-cohort study.

Official Title
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Associations Between Genetically Determined Low Vitamin D Level, Vitamin D Intake and Risk of Colorectal Cancer in a Prospective Case-cohort Study in Danes

Conditions
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Colorectal Cancer

Intervention / Treatment
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* Other: Observational


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Born in Denmark No previous cancers at study entry Age between 50-64 Exclusion Criteria: Previous or present cancer(s) at study entry

Ages Eligible for Study
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Minimum Age: 50 Years
Maximum Age: 64 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Colorectal cancer cases<br>1038 participants diagnosed with colorectal cancer from the Diet, Cancer and Health cohort. | Other: Observational<br>* Information on diet, lifestyle, weight, height, medical treatment, environmental exposures, and other socio-economic factors were collected at enrolment using questionnaires and interviews<br>|
| Sub-cohort members<br>1857 persons randomly selected within the full cohort at time of entry into the Diet, Cancer and Health cohort. These participants serve as controls for the colorectal cancer cases. | Other: Observational<br>* Information on diet, lifestyle, weight, height, medical treatment, environmental exposures, and other socio-economic factors were collected at enrolment using questionnaires and interviews<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of colorectal cancer in the DCH cohort | Risk of coloractal cancer compared to healthy sub-cohort members and interaction with Vitamin D metabolizing genes and vitamin D intake | Between 1994 and 31th December 2009 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Vitamin D, GC, CYP2R1, Gene-environment interaction, prospective case-cohort study, single nucleotide polymorphisms, colorectal cancer