Phase I Biomarker Study of Dietary Grape-derived Low Dose Resveratrol for Colon Cancer Prevention

January 22, 2021 updated by: University of California, Irvine
This study is designed to investigate the dietary influence of grapes in colon cancer prevention. A natural compound found in the skin of grapes, resveratrol, may protect against cancer by acting as an antioxidant (a chemical compound or substance that helps reduce damages due to oxygen). This compound is known to block colon cancer cell lines from growing in the laboratory. The purpose of this study is to determine the minimum amount of resveratrol-rich fresh red grapes needed to exhibit such signs of prevention.

Study Overview

Detailed Description

It has long been recognized that dietary factors influence the risk of developing colon cancer, with populations consuming a higher proportion of fruits and vegetables having lower risk. A compound found in the skin of grapes, resveratrol, has been purported to have colon cancer prevention activity though the dosages obtained through the diet have always seemed too low to produce inhibitory effects against cancer cells in the laboratory. We have found that low concentrations of resveratrol inhibit the Wnt pathway, a key signaling pathway which is activated in over 85% of colon cancers. We have also found in a small pilot trial that low dosages of freeze-dried grape powder can directly inhibit Wnt signaling in the normal colon and that grape powder was more effective than resveratrol alone in blocking Wnt throughput. This suggests that components of grapes may have direct activity in inhibiting a key signaling pathway and that this may correlate with cancer prevention activity.

In this study, we will directly test the impact of a diet containing a specific amount of red grapes in the context of a controlled amount of other resveratrol containing foodstuffs on Wnt signaling in the colon. This grape-supplemented diet provides a low-dose of resveratrol in conjunction with other potentially active components contained within the grapes. Participants will be normal volunteers and molecular studies will be done on colon tissue obtained by a limited flexible sigmoidoscopy before, and after, the red grape-containing diet is ingested. Different dosages of grapes will be utilized. This study will define the effect of dietary grape-derived low dose resveratrol on biomarkers related to the Wnt pathway, and provide critical information as to the utility of this nutritional approach toward colon cancer prevention.

For this study, seedless red grapes will be used. Ten participants will be enrolled at each dose level of grapes as follows:

  • Dose level 1: 1 lb/day fresh red grapes
  • Dose level 2: 2/3 lb/day fresh red grapes
  • Dose level 3: 1/3 lb/day fresh red grapes

Participants will be normal volunteers identified through advertisements, referrals, and community outreach.

Primary Objective:

Define the minimum dietarily achievable amount of resveratrol-rich fresh red grapes which are effective in inhibiting Wnt signaling in human colonic mucosa.

Secondary Objectives

  1. Define whether grape-supplemented diet affects colonic mucosa cell proliferation.
  2. Define any side-effects associated with the resveratrol-rich dietary program.

Study Type

Interventional

Phase

  • Phase 1

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • California
      • Orange, California, United States, 92868
        • University of California, Irvine Medical Center

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years and older (ADULT, OLDER_ADULT)

Accepts Healthy Volunteers

Yes

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • 18 years of age or older, male or female
  • Participants must sign informed consent for enrollment
  • Participants must have values for tests included in CBC, CMPAN and UA within normal range or no greater than 1.5x ULN or less than 0.75x LLN at prestudy to proceed to registration
  • Participants must have normal limited flexible sigmoidoscopic examination on Day 15 to proceed to re-registration
  • To receive Day 28 limited flexible sigmoidoscopy, participants must have taken >80% of prescribed dose of red grapes (based on food diary review)

Exclusion Criteria:

  • Pregnant or lactating (and/or elevated ßHCG at enrollment)
  • Known history of diabetes

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: PREVENTION
  • Allocation: RANDOMIZED
  • Interventional Model: PARALLEL
  • Masking: NONE

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
ACTIVE_COMPARATOR: Dose Level 1
1 lb/day fresh red grapes
1 pound of seedless red grapes
Other Names:
  • dietary
2/3 lb/day fresh red grapes
Other Names:
  • dietary
1/3 lb/day fresh red grapes
Other Names:
  • dietary
ACTIVE_COMPARATOR: Dose Level 2
2/3 lb/day fresh red grapes
1 pound of seedless red grapes
Other Names:
  • dietary
2/3 lb/day fresh red grapes
Other Names:
  • dietary
1/3 lb/day fresh red grapes
Other Names:
  • dietary
ACTIVE_COMPARATOR: Dose Level 3
1/3 lb/day fresh red grapes
1 pound of seedless red grapes
Other Names:
  • dietary
2/3 lb/day fresh red grapes
Other Names:
  • dietary
1/3 lb/day fresh red grapes
Other Names:
  • dietary

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
Expression and cellular localization of beta-catenin in intestinal mucosa: localization of β-catenin. Expression of Wnt pathway target genes in intestinal mucosa: Wnt target gene expression
Time Frame: 2 yrs
2 yrs

Secondary Outcome Measures

Outcome Measure
Time Frame
Define whether grape supplemented diet affects colonic mucosa cell proliferation. Ki67 staining method will be utilized on the pre- and post-resveratrol biopsy specimens.
Time Frame: 2 yrs
2 yrs
Define any side-effects associated with the resveratrol-rich dietary program. Laboratory testing is performed at specified timepoints in this protocol, along with history & physical, for the purposes of toxicity monitoring.
Time Frame: 2 yrs
2 yrs
Monitor resveratrol content of grapes throughout the course of the study. Grapes will be obtained from the same source as participants monthly throughout the study and the content of resveratrol will be measured.
Time Frame: 2 yrs
2 yrs

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: Randall F Holcombe, M.D., University of California, Irvine

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

December 1, 2007

Primary Completion (ACTUAL)

December 1, 2007

Study Completion (ACTUAL)

December 1, 2007

Study Registration Dates

First Submitted

December 18, 2007

First Submitted That Met QC Criteria

December 18, 2007

First Posted (ESTIMATE)

December 21, 2007

Study Record Updates

Last Update Posted (ACTUAL)

January 25, 2021

Last Update Submitted That Met QC Criteria

January 22, 2021

Last Verified

January 1, 2021

More Information

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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