Zijie Sun

Postdoctoral Advisees

Suk Hyung Lee,  Xanthi Stachtea

Graduate & Fellowship Program Affiliations

• Cancer Biology
• Genetics
• Urology

Current Research Interests

Transcriptional control is a key step in the regulation of eukaryotic gene expression. My lab focuses on understanding the molecular mechanism of transcription factors that govern the transformation of normal mammalian cells to a neoplastic state. We are especially interested in the action of the androgen receptor (AR) and interactions between AR and other signaling pathways in development and related human diseases. Our current efforts mainly focus on three different but closely related areas of research.

First, most previous GEM models for study of androgen action and prostate tumorigenesis were generated using the probasin promoter, an androgen-inducible promoter. Therefore, these mouse models can only be used to evaluate androgen-dependent effects. Recently, we generated a conditional AR transgenic mouse strain that can be used to evaluate the role of AR in the absence of androgens (castration). Using this novel mouse model, we are carrying out several projects to directly assess and recapitulate the critical role of AR in prostate development and prostate cancer initiation and progression.

Second, we are investigating a novel role of the AR as a transcriptional repressor. Specifically, we are focusing on AR action in repressing c-Met expression, which may provide fresh insight into the pathogenesis of castration resistant prostate cancer. Currently, using different in vivo and in vitro experimental approaches, we are testing the therapeutic strategy combining c-Met inhibition with standard androgen ablation for treatment of advanced prostate cancer patients.

Third, we are continuing to investigate the molecular mechanisms underlying the interaction between androgen and Wnt signaling pathways in urogenital development and related human diseases. Specifically, we are evaluating the biological role of LZTS2, a novel regulator of beta-catenin, in kidney development and tumorigenesis using the newly developed knockout mouse models.

Clinical Trials

• Identification and Characterization of Novel Proteins in Head and Neck Cancer Recruiting

Publications

• Conditional expression of the androgen receptor induces oncogenic transformation of the mouse prostate. Zhu C, Luong R, Zhuo M, Johnson DT, McKenney JK, Cunha GR, Sun Z. J Biol Chem. 2011; 286 (38): 33478-88
• The beta-catenin binding protein ICAT modulates androgen receptor activity. Zhuo M, Zhu C, Sun J, Weis WI, Sun Z. Mol Endocrinol. 2011; 25 (10): 1677-88
• The leucine zipper putative tumor suppressor 2 protein LZTS2 regulates kidney development. Peng Y, Clark C, Luong R, Tu WH, Lee J, Johnson DT, Das A, Carroll TJ, Sun Z. J Biol Chem. 2011; 286 (46): 40331-42
• ZMIZ1 preferably enhances the transcriptional activity of androgen receptor with short polyglutamine tract. Li X, Zhu C, Tu WH, Yang N, Qin H, Sun Z. PLoS One. 2011; 6 (9): e25040
• A novel role for protein inhibitor of activated STAT (PIAS) proteins in modulating the activity of Zimp7, a novel PIAS-like protein, in androgen receptor-mediated transcription. Peng Y, Lee J, Zhu C, Sun Z. J Biol Chem. 2010; 285 (15): 11465-75