Clifford G. Tepper, Ph.D.
Associate Research Biochemist
Research III, Room 2200A
4645 Second Avenue, Sacramento, CA 95817
Androgen Independence Research Dr. Tepper's laboratory is interested in identifying molecules that mediate survival of prostate cancer cells during androgen ablation therapy. We reasoned that adjuvant targeting of these molecules can delay or abolish the development of androgen independence by increasing apoptosis. To this end, we have utilized a combination of biochemical and microarray profiling to identify genes and pathways critical to androgen-independent survival. Data from the lab showed that the PI3K-Akt pathway is hyperactivated during androgen withdrawal (AW) and that pharmacological inhibition markedly induced apoptosis via combined FKHR transcription factor activation and diminished Bcl-2 expression.
Regulation of Androgen Receptor Expression Androgen ablation therapy of prostate cancer diminishes the androgen receptor (AR) pathway by antagonizing its function, thereby leading to a marked reduction in AR protein expression. However, hormone-refractory disease is generally characterized by AR pathway reinstatement distinguished by elevated levels of AR. One goal of Dr. Tepper's lab is to better understand this phenomenon by focusing upon mechanisms regulating AR expression, degradation, and stability. Data from the lab has shown that counter-regulatory polypeptide growth factor and androgen signaling influence steady-state AR levels by promoting degradation and stability, respectively. In the absence of androgen, AR levels decline rapidly via Akt phosphorylation and ubiquitin-mediated degradation. This is deregulated in androgen-independent sublines as they exhibited elevated AR levels in the presence of Akt hyperactivation.
2008 Gautschi, O., Tepper, C. G., Purnell, P. R., Izumiya, Y., Evans, C. P., Green, T. P., Desprez, P. Y., Lara, P. N., Gandara, D. R., Mack, P. C., Kung, H. J. Regulation of Id1 expression by SRC: implications for targeting of the bone morphogenetic protein pathway in cancer. Cancer Res, 68(7): 2250-8.
2008 Burich, R. A., Holland, W. S., Vinall, R. L., Tepper, C., de Vere White, R. W., Mack, P. C. Genistein combined polysaccharide enhances activity of docetaxel, bicalutamide and Src kinase inhibition in androgen-dependent and independent prostate cancer cell lines. BJU Int, 102: 1458-66.
2008 Shi, X. B., Tepper, C. G., de Vere White, R. W. Cancerous miRNAs and their regulation. Cell Cycle, 7(11): 1529-38.
2008 Shi, X. B., Tepper, C. G., de Vere White, R. W. MicroRNAs and prostate cancer. J Cell Mol Med, 12(5A): 1456-65.
2009 Guo, Z., Yang, X., Sun, F., Jiang, R., Linn, D. E., Chen, H., Kong, X., Melamed, J., Tepper, C. G., Kung, H. J., Brodie, A. M., Edwards, J., Qiu, Y. A novel androgen receptor splice variant is up-regulated during prostate cancer progression and promotes androgen depletion-resistant growth. Cancer Res, 69(6): 2305-13.
2009 Zou, J. X., Guo, L., Revenko, A. S., Tepper, C. G., Gemo, A. T., Kung, H. J., Chen, H. W. Androgen-induced coactivator ANCCA mediates specific androgen receptor signaling in prostate cancer. Cancer Res, 69(8): 3339-46.
Upper division courses
- 192 Internship in Biological Chemistry
- 198 Group Study
- 199 Special Study for Advanced Undergraduates
- 298 Group Study
- 299 Research
Professional courses for medical students
- 498 Group Study
- 499 Research