Related Experiment Videos
Chemoprevention of cancer
C E Szarka1, G Grana, P F Engstrom
1Division of Population Science, Fox Chase Cancer Center.
Abstract:
Chemoprevention is a strategy used to block the development of cancers in human beings. This emerging field has broad potential for influencing cancer incidence rates in defined high-risk groups and the general population. In this review, we define some of the mechanisms of carcinogenesis, describe some of the genetic markers of carcinogenesis, and list possible biomarkers that may serve as surrogate end points in chemoprevention studies. A major component of this review is a description of the agents that are currently under investigation in animal systems or in human trials. They are grouped according to the agents that block or suppress mutation, such as oltipraz, selenium, vitamin C and the flavones, or according to agents that block promotion and proliferation, such as difluoromethylornithine, tamoxifen, nonsteroidal antiinflammatory drugs, and the vitamin A derivatives. We describe the issues that are considered in the design of chemoprevention trials and in the phase I, II, and III components of these trials. The following national trials are discussed: the Breast Cancer Prevention Trial, which uses tamoxifen; the Prostate Cancer Prevention Trial, which uses finasteride; and a Lung Cancer Prevention Trial, which uses 13-cis-retinoic acid. The review ends with some insights about future studies in chemoprevention.
Insights
Chemoprevention strategies aim to block cancer development using various agents. This review explores mechanisms, biomarkers, and agents under investigation for cancer prevention trials.
Area of Science:
- Oncology
- Preventive Medicine
- Molecular Biology
Background:
- Chemoprevention offers a promising strategy to reduce cancer incidence in high-risk groups and the general population.
- Understanding carcinogenesis mechanisms and genetic markers is crucial for developing effective preventive interventions.
- Biomarkers are essential for serving as surrogate endpoints in chemoprevention studies.
Purpose of the Study:
- To review the mechanisms of carcinogenesis and identify potential biomarkers for chemoprevention.
- To describe agents currently under investigation for cancer prevention in preclinical and clinical settings.
- To discuss the design and components of chemoprevention trials, including national examples.
Main Methods:
- Literature review of carcinogenesis mechanisms, genetic markers, and biomarkers.
- Categorization of chemopreventive agents based on their mechanism of action (mutation suppression or promotion/proliferation blocking).
- Discussion of trial design principles and phases (I, II, III) with examples of national trials.
Main Results:
- Agents are grouped into those suppressing mutation (e.g., oltipraz, selenium, vitamin C, flavones) and those blocking promotion/proliferation (e.g., difluoromethylornithine, tamoxifen, NSAIDs, vitamin A derivatives).
- Key national trials, including the Breast Cancer Prevention Trial (tamoxifen), Prostate Cancer Prevention Trial (finasteride), and Lung Cancer Prevention Trial (13-cis-retinoic acid), are discussed.
- Insights into future directions for chemoprevention research are provided.
Conclusions:
- Chemoprevention research is advancing with a diverse range of agents and strategies.
- Careful trial design and biomarker selection are critical for successful chemoprevention studies.
- Future research should focus on refining existing strategies and exploring novel approaches for cancer prevention.