Jan 4, 2007 - Toward this end, we compared the effects of naturally occurring selenomethionine (SM) and Se- ... human prostate cancer. ' 2006 Wiley-Liss, Inc. .... pounds were removed; cells were rinsed with saline and fresh media added.
Int. J. Cancer: 120, 1410–1417 (2007) ' 2006 Wiley-Liss, Inc.
Differential effects of naturally occurring and synthetic organoselenium compounds on biomarkers in androgen responsive and androgen independent human prostate carcinoma cells John T. Pinto1*, Raghu Sinha2, Kate Papp1, Nicole D. Facompre2, Dhimant Desai2 and Karam El-Bayoumy2 1 Laboratory of Molecular Neurobiology, Cornell-Burke Medical Research Institute, White Plains, NY 2 Biochemistry and Molecular Biology, Penn State College of Medicine, Hershey, PA
Epidemiological studies and clinical trials show that selenium supplementation results in reduction of prostate cancer incidence; however, the form of selenium and mechanisms underlying protection remain largely unknown. Toward this end, we compared the effects of naturally occurring selenomethionine (SM) and Semethylselenocysteine (MSC) and synthetic 1,4-phenylenebis(methylene)selenocyanate (p-XSC) and p-xylylbis(methylselenide) pXMS) organoselenium compounds in androgen responsive (AR) LNCaP and its androgen independent clone (AI) LNCaP C4-2 human prostate carcinoma cells on cell growth, secretion of prostate specific antigen (PSA), intracellular redox status and genomic profiles with emphasis on identifying redox sensitive genes. Both p-XSC and p-XMS reduced cell number and total protein concentration compared to control-treated AR and AI cells, while SM and MSC exhibited no effect on growth of AR and AI cells. SM, p-XSC and p-XMS but not MSC inhibited levels of secreted PSA in AR cells. SM, MSC and p-XMS increased glutathione (GSH) levels in AI LNCaP cells. By contrast, in both cell types, only pXSC significantly decreased GSH concentrations to
