Selenomethionine treatment does not alter gene expression in normal squamous esophageal mucosa in a high-risk Chinese population

NCI-Frederick, Фредерик, Maryland, United States
Cancer Epidemiology Biomarkers & Prevention (Impact Factor: 4.13). 06/2006; 15(5):1046-7. DOI: 10.1158/1055-9965.EPI-06-0135
Source: PubMed


Selenium is a promising cancer chemoprevention agent. A recent randomized controlled chemoprevention trial found that selenomethionine (SeMet) supplementation for 10 months favorably effected a change in esophageal dysplasia grade among participants who started the trial with mild dysplasia. To further explore the role of SeMet in this trial, we compared gene expression profiles by treatment group using Affymetrix HU 133A chips in before/after supplementation paired normal esophageal biopsies from a subset of 29 trial participants, 16 who received SeMet, and 13 who received placebo. Using P < 0.001 as a cutoff, 11 differentially expressed genes were found in the SeMet supplementation group but these genes did not include either known selenoprotein genes or genes previously shown to be modulated by selenium treatment. Because the number of differentially expressed genes (n = 11) was less than expected by chance (n = 18), we concluded that SeMet supplementation had no measurable effect on gene expression in the normal squamous esophagus of these subjects with dysplasia.

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    • "This work demonstrated that expression profiling in animal models may lead to the identification of novel genes involved in human prostate cancer biology. Joshi et al. (2006) compared gene expression profiles using Affymetrix HU 133A chips in before/after supplementation paired normal esophageal biopsies. They found that the number of differentially expressed genes (n=11) was less than expected by chance (n=18). "
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