Effects of selenomethionine on the gene expression profile of cloned human prostate cancer cells representing a phenotypic continuum of cancer progression.

We previously characterized three cell clones that were derived by limiting dilution from a human prostate cancer cell line (LNCaP) representing a phenotypic continuum of cancer progression (1). The present study was undertaken to examine the effects of L-selenomethionine (SeM), a potential cancer chemopreventive agent, on the gene expression profile of the cultured cell clones. Following a three-day incubation period with SeM, total RNA was extracted, and the gene expression profile was evaluated using Affymetrix human HG U133A microarrays and analyzed by ViaLogy's (Altadena, CA) VMAxS platform deploying quantum resonance interferometry (QRI) processing. The differentially expressed genes and corresponding biological processes were compared across the different treatments and cell types. Whereas SeM significantly affected RNA-DNA metabolism and protein transport and metabolism in all of the cell types evaluated, significant effects of SeM on genes mainly involved in the pathways of cell cycle, growth, differentiation, and apoptosis were observed only in the cell clone with a more malignant phenotype.