Human prostate cell cultures

Lycopene Oxidation, Uptake, and Activity in Human Prostate Cell Cultures... 

Results obtained from human prostate cell cultures and cell-free systems demonstrated inhibitory effects of palmitoleic, oleic, and myristoleic acids on the activity of human and rat microsomal 5a-reductase, which converts testosterone into 5a-dihydrotestosterone (Liang and Liao, 1992). The latter binds to androgen receptors and functions in the nucleus to regulate the expression of specific genes. 5a-Dihydrotestosterone promotes benign prostatic hyperplasia and female hirsutism. Certain 4-azasteroids are potent competitive inhibitors of 5a-dihydrotestosterone and have shown therapeutic value for treating prostate cancer. The inhibitory effect of palmitoleic acid on microsomal 5a-reductase activity may represent a mechanism related to its anti-tumour effects. 

F6. Figueroa, J. A., Lee, A. V., Jackson, J. G., and Yee, D., Proliferation of cultured human prostate cells is inhibited by insulin-like growth factor (IGF) binding protein-1 Evidence for an IGF-II... 

All-trans lycopene is rapidly isomerized to an equilibrium mixture with its cis isomers both in cell culture medium (Liu et al. 2006) and in vivo in prostate tissue (Clinton et al. 1996, van Breemen et al. 2002). The cis isomers of lycopene are absorbed better than the all -trans isomers when fed to humans (Unlu et al. 2007). The 5 -cis isomer predominates in plasma (Gustin et al. 2004). Since lycopene absorption by prostate cells might be due to facilitated diffusion (Liu et al. 2006), it is likely that the cis isomers of lycopene form a significant proportion of intracellular lycopene in the experiments that are reviewed later. 

Although the influence of lycopene and proliferation of carcinoma cells appears not limited to its ability to modulate Cx43 expression, lycopene as well as its oxidation products have been reported to enhance GJC in cultured cells (Livny et al., 2002 Stahl et al., 2000). Recent data indicate that lycopene may indeed increase connexin-43 expression in human prostate (Kucuk et al., 2001). 

Singh AV, Xiao D, Lew KL, Dhir R, Singh SV. (2004) Sulforaphane induces caspase-mediated apoptosis in cultured PC-3 human prostate cancer cells and retards growth of PC-3 xenografts in vivo. Carcinogenesis 25 83-90. 

SR038 Delos, S., ]. L. Carsol, E. Ghazarossian, ]. P. Raynaud, and P. M. Martin. Testosterone metabolism in primary cultures of human prostate epithelial cells and fibroblasts. J Steroid Biochem Mol Biol 1995 55(3-4) 375-383. 

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