Changes in Serum Proteomic Patterns by Presurgical α-Tocopherol and l-Selenomethionine Supplementation in Prostate Cancer
- Jeri Kim1,
- Peiyu Sun6,
- Ying-Wai Lam6,
- Patricia Troncoso2,
- Anita L. Sabichi3,
- Richard J. Babaian4,
- Louis L. Pisters4,
- Curtis A. Pettaway4,
- Christopher G. Wood4,
- Scott M. Lippman3,
- Timothy J. McDonnell5,
- Ronald Lieberman7,
- Christopher Logothetis1 and
- Shuk-Mei Ho6
- Departments of 1Genitourinary Medical Oncology, 2Pathology, 3Clinical Cancer Prevention, 4Urology, and 5Molecular Pathology, University of Texas M.D. Anderson Cancer Center, Houston, Texas; 6Department of Surgery, Division of Urology, University of Massachusetts Medical School, Worcester, Massachusetts; and 7Prostate and Urologic Cancer Research Group, Division of Cancer Prevention, National Cancer Institute, Bethesda, Maryland
- Requests for reprints:
Shuk-Mei Ho, University of Massachusetts Medical School, Lazare Research Building, Room 504, 364 Plantation Street, Worcester, MA 01605-2324. Phone: 508-856-1909; Fax: 508-856-8699. E-mail: shuk-mei.ho{at}umassmed.edu
Abstract
Background: Evidence of the chemopreventive effects of the dietary antioxidants α-tocopherol (vitamin E) and l-selenomethionine (selenium) comes from secondary analysis of two phase III clinical trials that found treatment with these antioxidants reduced the incidence of prostate cancer. To determine the effects of selenium and vitamin E in blood and prostate tissue, we undertook a preoperative feasibility study complementary to the currently ongoing Selenium and Vitamin E Cancer Prevention Trial.
Methods: Forty-eight patients with clinically localized prostate cancer enrolled on this 2 × 2 factorial design study were randomized to take selenium, vitamin E, both, or placebo for 3 to 6 weeks before prostatectomy. Sera were collected from patients before and after dietary supplementation. Thirty-nine patients were evaluable, and 29 age-matched disease-free men served as controls. Mass profiling of lipophilic serum proteins of lower molecular weight (2-13.5 kDa) was conducted, and mass spectra data were analyzed using custom-designed software.
Results: Weighted voting analyses showed a change in sera classification from cancerous to healthy for some patients with prostate cancer after dietary intervention. ANOVA analysis showed significantly different treatment effects on prediction strength changes among the four groups at a 95% confidence level. Eliminating an outlying value and performing post hoc analysis using Fisher's least significant difference method showed that effects in the group treated with the combination were significantly different from those of the other groups.
Conclusion: In sera from patients with prostate cancer, selenium and vitamin E combined induced statistically significant proteomic pattern changes associated with prostate cancer–free status.
Footnotes
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↵8 Modulized Classification System, Sun and Ho, unpublished.
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Grant support: Research grants CA88761 and CA88084 (to J. Kim) from the National Cancer Institute, NIH, Department of Human Services.
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The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked advertisement in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
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Note: J. Kim and P. Sun contributed equally to this work.
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- Accepted April 21, 2005.
- Received September 14, 2004.
- Revision received April 11, 2005.
