Changes occur in the sensitivity of the individual lobes of the rat prostate to androgen during aging. These studies provide a fundamental basis for studies of cell proliferation and cell death related to age-dependent alterations in tissue- and cell-specific structure and function associated with carcinogenesis and hyperplasia of the prostate. We are currerntly investigating the regulation of stem/progenitor cell renewal, proliferation and differentiation in the aging prostate. We are particularly interested in how the stromal-epithelial cell microenvironment influences the quiescence and proliferation of stem/progenitor cells relative to the pathogenesis of prostatic hyperplasia in aging rats and men.

A second project focuses upon spermatogenesis and its dependence upon adequate levels of intratesticular androgen, primarily testosterone, and how the androgen receptor mediates the actions of androgens in Sertoli cells. Our goal is to identify and characterize the transcription factors that regulate AR gene expression and other factors that interact with AR to facilitate or repress its activity in the regulation of androgen-dependent genes in the testis.

Biochemistry and molecular biology, reproductive biology, androgens, androgen receptor, prostate, testis, male reproduction

President, American Society of Andrology 2007-08 President, Faculty Senate, Bloomberg School of Public Health 2009-10

Gene expression changes are age-dependent and lobe-specific in the brown Norway rat model of prostatic hyperplasia. Bethel CR, Chaudhary J, Anway MD, Brown TR. Prostate. 2009 Jun 1;69(8):838-50.

Differential age-associated regulation of clusterin expression in prostate lobes of brown Norway rats. Omwancha J, Anway MD, Brown TR. Prostate. 2009 Feb 1;69(2):115-25.

Regulation of energy metabolism pathways by estrogens and estrogenic chemicals and potential implications in obesity associated with increased exposure to endocrine disruptors. Chen JQ, Brown TR, Russo J. Biochim Biophys Acta. 2009 Jul;1793(7):1128-43.

Mechanisms of hormone carcinogenesis: evolution of views, role of mitochondria. Chen JQ, Brown TR, Yager JD. Adv Exp Med Biol. 2008;630:1-18. Review.

Effect of glutathione depletion on Leydig cell steroidogenesis in young and old brown Norway rats. Chen H, Pechenino AS, Liu J, Beattie MC, Brown TR, Zirkin BR. Endocrinology. 2008 May;149(5):2612-9.

Cell proliferation and expression of cell cycle regulatory proteins that control the G1/S transition are age dependent and lobe specific in the Brown Norway rat model of prostatic hyperplasia. Yan J, Brown TR. Endocrinology. 2008 Jan;149(1):193-207.

Serum estrogen, but not testosterone, levels differ between black and white men in a nationally representative sample of Americans. Rohrmann S, Nelson WG, Rifai N, Brown TR, Dobs A, Kanarek N, Yager JD, Platz EA. J Clin Endocrinol Metab. 2007 Jul;92(7):2519-25.

A naturally occurring mutation in the human androgen receptor of a subject with complete androgen insensitivity confers binding and transactivation by estradiol. Bonagura TW, Deng M, Brown TR. Mol Cell Endocrinol. 2007 Jan 15;263(1-2):79-89. Epub 2006 Oct 2.

Superoxide dismutase in the prostate lobes of aging Brown Norway rats. Pechenino AS, Brown TR. Prostate. 2006 Apr 1;66(5):522-35.

Selective androgen receptor modulators: in pursuit of tissue-selective androgens. Omwancha J, Brown TR. Curr Opin Investig Drugs. 2006 Oct;7(10):873-81. Review.