James Eliason, Ph.D.
Stephen Ethier, Ph.D.
Joseph A. Fontana MD, Ph.D.
Fred R. Miller, Ph.D.
Robert J. Pauley, Ph.D.
Arun K. Rishi, Ph.D.
Fazlul H. Sarkar, Ph.D.
Malathy Shekhar, Ph.D.
Shijie Sheng, Ph.D.
Debra F. Skafar, Ph.D.
Guri Tzivion, Ph.D.
Wei-Zen Wei, Ph.D.

James Eliason, Ph.D.
Hematology and Oncology
Ph.D., University of Chicago, 1978

Our recent research efforts have been in the area called translational research, specifically to develop better tools for studying cancer from patient tissue samples. Follow-up clinical data is important for many studies on the prognostic implications of various cancer biomarkers. Samples with this type of follow-up information are usually only available as formalin fixed, paraffin embedded clinical diagnostic samples. The fixation process leads to degradation RNA, DNA and proteins so that different technologies have to be applied that are used with cell lines, animal tumors or fresh frozen patient tumors. One area of research in our laboratory is to develop methods that will allow us to predict which patients are resistant to chemotherapeutic agents and thus can be spared the toxicities. We have developed a novel assay enabling us to measure the ratios of two proteins in fixed tissue sections from patient tumors and map them using laser scanning cytometry. We are using this assay to examine expression of the enzyme responsible for activating a commonly used anticancer prodrug, capecitabine, and the enzyme responsible for breakdown of its active product, 5-FU. We have been working with a novel gene microarray technique that allows us to work with RNA extracted from fixed tissues. This enables us to look at large numbers of genes at the same time.

Selected Publications

Cortese, JF, Gowda, AL, Wali, A, Eliason, JF, Pass, HI, and Everson, RB Common EGFR mutations conferring sensitivity to gefitinib in lung adenocarcinoma are not prevalent in human malignant mesothelioma. Int J Cancer, 118: 521-2, 2006.

Yang, LV, Wan, J, Ge, Y, et al. The GATA site-dependent hemogen promoter is transcriptionally regulated by GATA1 in hematopoietic and leukemia cells. Leukemia, 20: 417-25, 2006.

Haller, AC, Kanakapalli, D, Walter, R, Alhasan, S, Eliason, JF, and Everson, RB Transcriptional profiling of degraded RNA in cryopreserved and fixed tissue samples obtained at autopsy. BMC Clin Pathol, 6: 9, 2006.

Glazyrin, A, Shen, X, Blanc, V, and Eliason, JF Direct detection of herceptin/trastuzumab binding on breast tissue sections. J Histochem Cytochem, 55: 25-33, 2007.

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Stephen Ethier, Ph.D.
Breast Cancer
Ph.D., University of Tennessee, Oak Ridge Graduate School of Biomedical Science, 1982

The goals of the Ethier lab are to understand the genetic basis for the development and progression of human breast cancer and to understand how specific genetic alterations contribute to specific aspects of the transformed phenotype. For many years, the Ethier lab has worked to understand the nature of the altered signaling pathways activated by the HER-2 oncoprotein and by the epidermal growth factor receptor when it is over expressed in breast cancer cells. More recently, the lab has developed a focus on discovering novel oncogenes in human breast cancer by investigating specific genomic regions that are commonly increased in copy number in breast cancer. Current studies are centered on the 8p11 region of the genome, which is amplified in approximately 25% of all breast cancers. To date, three novel breast cancer oncogenes have been mapped to this region. Finally, the Ethier lab is using state-of-the-science bioinformatics methodologies to understand better the mechanistic basis for the transforming properties of newly discovered breast cancer oncogenes.

Selected Publications

Streicher, KL, Yang, Z.Q., Draghici, S., and Ethier, S.P.  “Transforming function of the LSM1 oncogene in human breast cancers with the 8p11-12 amplicon”  Oncogene.  September 2006.

Moffa, A., and Ethier, S.P.  “Differential signal transduction of alternatively spliced FGFR2 variants expressed in human mammary epithelial cells.”  J Cell Physiol. November 2006.

Willmarth, N., and Ethier, S.P.  “Autocrine and juxtacrine effects of amphiregulin on the proliverative, invasive, and migratory properties of normal and neoplastic human mammary epithelial cells”. Journal of Biological Chemistry,  281 (49): 37728-37 December 2006.

Yang, Z.Q., Streicher, K.L., Ray, M.E., Abrams, J. and Ethier, S.P.  “Multiple interacting oncogenes on the 8p11-p12 amplicon in human breast cancer.”  Cancer Research 66(24) 11632-11643, 2006.

Neve, R.M., Chin, K., Devries, S., Fridyland, J., Baehner, F.R., Yeh, J., Coppe, J.P., Lapuk, A.,Clark, L., Bayani, N., Tong, F., Speed,T., Stilwell, J., Chew, K., Spellman, P.T., Pinkel, D., Albertson, D., Waldman, F., Ethier, S.P., Gazdar, A., and Gray, J.W. “A breast cancer cell line’ system’ for functional cancer genomics”.  Cancer Cell 10 (6) 515-527, 2006.

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Joseph A. Fontana MD, Ph.D.
Breast Cancer
Ph.D., Johns Hopkins University, 1969
MD, University of Pennsylvania, 1975

Our research effort centers on ascertaining the mechanism of action and potential therapeutic efficacy of a novel class of compounds which we have now synthesized. This class of compound is adamantly derivatives of retinoid-like compounds; however, these compounds possess a unique mechanism(s) of action which does involve the retinoid nuclear receptors. This novel class of compounds are potent inducers of apoptosis of malignant cells both in vitro and in vivo. Our current objectives are to 1) identify a potential receptor for this class of compounds and discern the mechanism by which this receptor is activated. 2) Identify the intermediates involved through which this novel class of compounds triggers apoptosis. 3) Synthesis analogs of this class of compounds which display enhanced in vitro efficacy and or decreased toxicity translating into enhanced in vivo efficacy against malignant cell growth.

Selected Publications

Farhana L, Dawson MI, Huang Y, Zhang Y, Rishi AK, Reddy K, Freeman R, and Fontana JA. Apoptosis signaling by the novel compound 3-Cl-AHPC involves EGFR proteolysis and accompanying decreased phosphatidylinositol 3-kinase and AKT activities. Oncogene 23; 1874-18884, 2004.

Dawson MI, Harris DL, Liu G, Hobbs PD, Lange CW, Jong L, Bruey-Sedano N, James SY, Zhang X-k, Peterson VJ, Leid M, Farhana L, Rishi AK, and Fontana JA. 6-[3’-(1-adamantyl)-4’-hydroxyphenyl]-2-naphthalenecarboxylic acid (AHPN) family of apoptosis unducers that effectively blocks AHPN-induced apoptosis but not cell cycle arrest. J. Medicinal Chem. 47: 3518-3536,, 2004.

Farhana L, Dawson MI, and Fontana JA. Apoptosis induction by a novel retinoid related molecule requires NF?B activation. Cancer Res 65: 4909-4917, 2005.

Fred R. Miller, Ph.D.
Breast Cancer
Ph.D., University of Wisconsin-Madison, 1976

This laboratory has undertaken a genomic and proteomic analysis of progression in the development of breast cancer from high risk premalignant epithelium and the other is in developing a system of high risk human breast epithelium to detect chemopreventive activity of dietary and pharmacological agents. The MCF10AT model is a xenograft system of human breast epithelial cells that span the spectrum from normal, atypical hyperplasia, ductal carcinoma in situ (DCIS), and invasive carcinomas and which therefore constitute a model of early breast cancer progression. We are attempting to identify protein isoforms expressed constitutively in malignant MCF10CA variants that are also induced by E2 in premalignant MCF10AT1 cells. In addition to the detection and separation of proteins of potential relevance to breast cancer progression, the MCF10 system provides a direct means to test the cause and effect relationship of the detected change to the malignant phenotype.

Selected Publications

Miller, F.R. Xenograft models of premalignant human breast disease. Journal of Mammary Gland Biology and Neoplasia 5:379-391, 2000.

Hamler, R.L., Zhu, K., Buchanan, N.S., Kreunin, P., Kachman, M.T., Miller, F.R., Lubman, D.M. A two-dimensional liquid-phase separation method coupled with mass spectrometry for proteomic studies of breast cancer and biomarker identification. Proteomics  4:562-577, 2004.

Zhao, J., Zhu, K., Lubman, D.M., Miller, F.R., Barder, T.J. Proteomic analysis of estrogen response of premalignant human breast cells using a 2-D liquid separation/mass mapping technique. Proteomics 6:3847-3861, 2006.

Tait, L.R., Pauley, R.J., Santner, S.J., Heng, H.H., Heppner, G.H., Rak, J.W., Miller, F.R.  Dynamic stromal-epithelial interactions during progression of MCF10DCIS.com xenografts. International Journal of Cancer120:2127-2134, 2007.

Normal development and differentiation of breast tissue require complex interactions between epithelial cells within the parenchyma and both fibroblasts and myofibroblasts within the stroma.  Changes in the structural organization and function of parenchymal epithelial cells and of stromal fibroblasts characterizes breast neoplasia.  Our research has focused upon the establishment and characterization of key parenchymal and stromal cellular components, as well as to evaluate these for properties important to normal development and neoplasia.  Our studies demonstrated that breast stromal cells in vitro synthesize estrogens by the rate limiting aromatase enzyme, and that CYP19/aromatase gene regulation involves multiple alternative transcription initiation sites that are differentially regulated by hormones and growth factors in stromal myofibroblasts from normal, benign and tumor breast tissues. Breast parenchymal epithelial cells were propagated from breast reduction mammoplasty tissue and demonstrated to exhibit properties of differentiated breast epithelial cells in vitro, including homotypic cell-cell interactions and to acquire a neoplastic phenotype upon transfection.  Recent studies concern three-dimensional in vitro homotypic and heterotypic cell-cell interactions between breast epithelial cells and fibroblasts to model breast tissue differentiation and the neoplastic process, and parallel in vivo studies including a cell line that forms in xenografts lesions containing features of ductal carcinoma in situ, an established human preneoplastic condition for breast cancer, as well as comedo/apoptotic differentiation..

Selected Publications

Pauley, R.J., Soule, H.D., Tait, L., Miller, F.R., Wolman, S.R., Dawson, P.J., Heppner, G.H.  The MCF10 Family of Spontaneously Immortalized Human Breast Epithelial Cell Lines: Models of Neoplastic Progression. European Journal of Cancer Prevention, 2:67-76, 1993.

Miller, F.R., Soule, H.D., Tait, L., Pauley, R.J., Wolman, S.R., Dawson, P.J., Heppner, G.H.  Xenograft Model of Progressive Human Proliferative Breast Disease. J. Natl. Cancer Inst., 85:1725-1737, 1993.

Santner, S.J., Pauley, R.J., Tait, L., Kaseta, J., Santen, R.J.  Aromatase Expression and Regulation in Breast Cancer and Benign Breast Tissue Stromal Cells. J. Clinical Endocrinology and Metabolism, 82:1-9, 1997.

Pauley, RJ, SJ Santner, LR Tait, RK Bright, RJ Santen. Regulation of CYP19 Aromatase in Breast Stromal Fibroblasts.  J. Clinical Endocrinology and Metabolism, 85 (2): 837-846, 2000.

Shekhar, M.P.V., J Werdell, S.J. Santner, R.J. Pauley, L. Tait.  Breast Stroma Plays a Dominant Regulatory Role in Breast Epithelial Growth and Differentiation: Implications for Tumor Development and Progression. Cancer Res 61: 1320-1326, 2001.

Shekhar, M.P.V., R.J. Pauley, G. Heppner. Host microenvironment in breast cancer development:  extracellular matrix-stromal cell contribution to the neoplastic phenotype of epithelial cells in the breast.  Breast Cancer Research 5:  130-135, 2003.

Shen, C., F. Miller, L. Tait, S.J. Santner, R. Pauley, A. Raz, M.A. Tainsky, S.C. Brooks, and Y.A. Wang.  Isolation and characterization of a breast progenitor epithelial cell line with robust DNA damage responses.  Breast Cancer Research & Treatment 98:  357-364, 2006.

Tait, L., R.J. Pauley, S.J. Santner, G.H. Heppner, H.H. Heng, J.W. Rak and F.R. Miller.  Dynamic stromal-epithelial interactions during progression of MCF10DCIS.com xenografts.  Int. J. Cancer 120:  2127-2134, 2007.   

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Arun K. Rishi, Ph.D.
Breast Cancer
Ph.D., Imperial College of Science,
Technology, & Medicine, University of London, U.K., 1987

Research in our laboratory focuses on elucidating pathways regulating cellular growth and apoptosis.  Recently, we described identification and characterization of a novel, apoptosis-regulatory protein termed CARP-1. CARP-1 regulates cell-growth inhibitory and apoptosis-promoting signals by chemotherapy drug adriamycin as well as a novel class of apoptosis-inducing adamantyl retinoids. CARP-1 also regulates epidermal growth factor (EGFR)-dependent signaling events since inhibition of EGFR by ERRP (EGFR-Related Protein, a novel negative regulator of EGFR) causes CARP-1 activation and apoptosis. Loss of CARP-1 inhibits apoptosis induction by ERRP.  While it is evident that CARP-1 is an important apoptosis signal transducer, it is still entirely unclear how CARP-1-dependent apoptosis is accomplished. Our data from biopsies of human breast, colon cancers and lymphomas suggest an inverse correlation of CARP-1 expression with the grades of the tumors, indicating a potential tumor suppressor property of CARP-1. Administration of peptide(s) derived from CARP-1 suppresses growth of human breast cancer cells in vitro as well as human breast cancer cell-derived tumor xenografts in vivo. Our current focus is to understand the apoptosis inducing pathways utilized by CARP-1 that will, in turn, help us define mechanism(s) of action of agents such as ERRP, adriamycin, and ARs to facilitate identification of potential novel targets and development of efficacious therapies against human breast cancer.

Selected Publications

Rishi, A.K., Sun, R-J., Gao, Y., Hsu, C.K.A., Gerald, T.M., Sheikh, M.S., Dawson, M.I., Reichert, U., Shroot, B., Fornace, A.J., Brewer, G., and Fontana, J.A. Posttranscriptional regulation of DNA damage inducible GADD45 gene in the human breast carcinoma cells exposed to a novel retinoid CD437. Nucleic Acids Research 27, 3111-3119, 1999.

Yu, Y., Rishi, A. K., Turner, J. R., Liu, D., Black, E. D., Moshier, J.A., and Majumdar, A.P.N. Cloning of a novel EGFR related peptide: A putative negative regulator of EGFR. American J. Physiology: Cell Physiology  280, C1083-C1089, 2001.

Marciniak, D.J., Moragoda, L., Mohammad, R., Yu, Y., Nagothu, K.K., Aboukameel, A., Sarkar, F.H., Adsay, V.N., Rishi, A.K., and Majumdar, A.P.N. Epidermal growth factor receptor related protein (ERRP): A potential therapeutic agent for colorectal cancer. Gastroenterology 124, 1337-1347, 2003.

Rishi, A.K., Zhang, L., Boyanapalli, M., Wali, A., Mohammad, R.M., Yu, Y., Fontana, J.A., Hatfield, J.S., Dawson, M.I., Majumdar, A.P.N., and Reichert, U. Identification and characterization of a Cell-Cycle and Apoptosis Regulatory Protein (CARP)-1 as a novel mediator of apoptosis signaling by retinoid CD437.  J. Biol. Chem. 278, 33422-33435, 2003.

Rishi, A.K., Zhang, L., Yu, Y., Jiang, Y., Nautiyal, J., Wali, A., Fontana, J.A., Levi, E., Majumdar, A.P.N. Cell cycle and apoptosis regulatory protein (CARP)-1 is involved in apoptosis signaling by epidermal growth factor receptor. J. Biol. Chem. 281, 13188-98, 2006.

Zhang, L., Levi, E., Majumder, P., Yu, Y., Aboukameel, A., Du, J., Xu, H., Mohammad, R.M., Hatfield, J.S., Wali, A., Adsay, V., Majumdar, A.P.N., and Rishi, A.K. TAT-tagged Cell Cycle and Apoptosis Regulatory Protein (CARP)-1 peptides suppress growth of human breast cancer cells in vitro and in vivo. Mol. Cancer Ther. 6(5): 1661-1672, 2007.

Zhang, L., Wali, A., Ramana, C.V., Rishi, A.K. Cell growth inhibition by okadaic acid involves gut-enriched kruppel-like factor-mediated enhanced expression of c-Myc. Cancer Research (in Press), 2007.

Majumdar, A.P.N., Du, J., Yu, Y., Xu, H., Levi, E., Patel, B.B., and Rishi, A.K. cell cycle and apoptosis regulatory protein (CARP)-1: a novel regulator of apoptosis in the colonic mucosa during aging. American J. Physiology: Gastrointestinal and Liver Physiology (in Press), 2007.

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The process of cancer development and progression requires modulation of multiple genetic factors. Differential gene expression and regulation of specific genes appear to play an important role in the developmental cascade of cancer. Many oncogenes and tumor suppressor genes have been shown to be involved in such processes. Investigations are being pursued to study the differential expression of growth factor/growth factor receptor genes, oncogenes and tumor suppressor genes, in understanding the biology of human adenocarcinomas. Parallel investigations are also being pursued to understand the regulation of some key genes in the development and progression of breast and prostate cancer. The identification and characterization of novel transcription factors which regulate the transcription of some key genes may ultimately lead to the understanding of the effects of these genes in cellular growth, differentiation and programmed cell death (apoptosis). Since the development of a cancer mass is dependent upon the ratio of cellular proliferation and apoptotic cell death, molecular biological understanding of some of these genes (which are actively involved in the regulation of cell cycle and apoptotic processes) should yield information that will facilitate the development of novel preventive and therapeutic agents along with traditional treatment modalities for the management of human adenocarcinoma. The current research areas of focus include chemoprevention, molecular mechanism of action of novel agents, research on cellular signaling molecules, processes of cell growth inhibition and apoptosis and clinical translational research involving clinical trials.

Selected Publications

Li Y, Kucuk O, Hussain M, Abrams J, Cher ML, Sarkar FH.  Antitumor and Antimetastatic Activities of Docetaxel Are Enhanced by Genistein through Regulation of Osteoprotegerin/Receptor Activator of Nuclear Factor-{kappa}B (RANK)/RANK Ligand/MMP-9 Signaling in Prostate Cancer.  Cancer Res. 66(9): 4816-25, 2006.

Rahman KW, Li Y, Wang Z, Sarkar SH, Sarkar FH.  Gene expression profiling revealed survivin as a target of 3,3'-diindolylmethane-induced cell growth inhibition and apoptosis in breast cancer cells.  Cancer Res. 66(9): 4952-60, 2006.

Wang Z, Sengupta R, Banerjee S, Li Y, Zhang Y, Rahman KM, Aboukameel A, Mohammad R, Majumdar AP, Abbruzzese JL, Sarkar FH.  Epidermal growth factor receptor-related protein inhibits cell growth and invasion in pancreatic cancer. Cancer Res. 1:66(15):7653-60, 2006.

Bhuiyan MM, Li Y, Banerjee S, Ahmed F, Wang Z, Ali S, Sarkar FH. Down-regulation of androgen receptor by 3,3'-diindolylmethane contributes to inhibition of cell proliferation and induction of apoptosis in both hormone-sensitive LNCaP and insensitive C4-2B prostate cancer cells. Cancer Res. 15;66(20):10064-72, 2006.

El-Rayes BF, Ali S, Ali IF, Philip PA, Abbruzzese J, Sarkar FH. Potentiation of the effect of erlotinib by genistein in pancreatic cancer: the role of Akt and nuclear factor-kappaB. Cancer Res. 1;66(21):10553-9, 2006.

Banerjee S, Zhang Y, Wang Z, Che M, Chiao PJ, Abbruzzese JL, Sarkar FH. In vitro and in vivo molecular evidence of genistein action in augmenting the efficacy of cisplatin in pancreatic cancer. Int J Cancer. 120(4):906-17, 2007.

Kong D, Li Y, Wang Z, Banerjee S, Sarkar FH. Inhibition of angiogenesis and invasion by 3,3'-diindolylmethane is mediated by the nuclear factor-kappaB downstream genes MMP-9 and uPA that regulated bioavailability of vascular endothelial growth factor in prostate cancer. Cancer Res. Apr 1;67(7):3310-9, 2007.

Banerjee S, Hussain M, Wang Z, Saliganan A, Che M, Bonfil D, Cher M, Sarkar FH. In vitro and in vivo molecular evidence for better therapeutic efficacy of ABT-627 and taxotere combination in prostate cancer. Cancer Res. Apr 15; 67(8):3818-26, 2007.

Schmelz EM, Xu H, Sengupta R, Du J, Banerjee S, Sarkar FH, Rishi AK,
Majumdar AP. Regression of Early and Intermediate Stages of Colon Cancer
by Targeting Multiple Members of the EGFR Family with EGFR-Related
Protein. Cancer Res. 67(11):5389-96, 2007.

Li Y, Wang Z, Kong D, Murthy S, Dou QP, Sheng S, Reddy GP, Sarkar FH.
Regulation of FOXO3a/beta-catenin/GSK-3beta signaling by
3,3'-diindolylmethane contributes to inhibition of cell proliferation
and induction of apoptosis in prostate cancer cells. J Biol Chem. 282(29):21542-50,2007

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Malathy Shekhar, Ph.D.
Breast Cancer Program
Ph.D., Indian Institute of Science, 1985

Our research interest is focused on understanding the mechanisms that influence responsiveness/resistance of breast cancer cells to hormones or chemotherapy. It is a well known fact that a third of ERa+ breast tumors fail to respond to antiestrogens despite retention of ERa expression, and majority of ERa+ tumors subsequently develop resistance to antiestrogens. Our hypothesis is that the stromal microenvironment plays a dominant role in influencing or modulating hormonal responsiveness of the breast epithelium. We have developed a novel three-dimensional model system that permits reciprocal interactions between breast stromal cells and epithelial cells, and produces phenotypic changes in the epithelium that are reminiscent of those observed in vivo. This 3-D coculture system allows us to delineate the effects of normal versus tumor-derived stroma on normal versus premalignant breast epithelial cells. We are currently using this system to evaluate functional roles/effects of tumor-derived stroma on breast epithelial growth and response to estrogen/antiestrogens. Towards understanding mechanisms regulating response/resistance to chemotherapeutic drugs, we have identified and characterized the gene Rad6B. Like Rad51, which is a fundamental component of recombination dependent DNA repair, Rad6 is a fundamental component of the postreplication DNA repair or error-prone repair pathway. It is a ubiquitin conjugating enzyme and its function is dependent upon its ubiquitin conjugating activity. Mutation of the ubiquitin conjugating catalytic site renders the cells hypersensitive to a variety of DNA damaging agents; conversely, overexpression of the wild type Rad6 induces resistance to a variety of DNA damaging agents. Our studies have shown that tight regulation of Rad6 expression is essential for maintenance of genomic integrity of breast cells. Rad6 is physically complexed with p53, and treatment with chemotherapeutic drugs results in recruitment of p14ARF into Rad6-p53 complexes and monoubiquitination of p53. Interaction and stabilization of p53 by Rad6 during DNA damage response is required for maintenance of the fidelity of repair process.

Selected Publications

Shekhar, P.V.M., Werdell, J, Santner, S., Pauley, R.J., and Tait, L Breast stroma plays a dominant regulatory role in breast epithelial growth and differentiation: implications for tumor development and progression. Cancer Res., 61, 1320-1326, 2001.

Shekhar, P.V.M., Lyakhovich, A., Heng, H., Visscher, D.W.. and Kondrat, N. RAD6 overexpression induces centrosome amplification, abnormal mitosis, aneuploidy and transformation. Cancer Res., 62:2115-2124,2002.

Lyakhovich, A. and Shekhar, P.V.M. Supramolecular complex formation between Rad6 and proteins of p53 pathway during DNA damage-induced response. Mol. and Cell. Biol, 23: 2463-2475, 2003.

Lyakhovich, A. and Shekhar, P.V.M.  RAD6B overexpression confers chemoresistance: RAD6 distribution during cell cycle, and its redistribution to chromatin during DNA damage-induced response. Oncogene, 23:3098-3107, 2004.

Shekhar, P.V.M., Nangia-Makker, P, Tait, L, Miller, F, and Raz, A. Alterations in galectin-3 expression and distribution correlate with breast cancer progression: Functional analysis of galectin-3 in breast epithelial-endothelial interactions. Amer. J Pathol., 165: 1931-1941, 2004.

Shekhar, P.V.M., Tait, L., and Gerard, B. Essential role of TCF/b-catenin in regulation of Rad6B: A potential mechanism for Rad6B overexpression in breast cancer cells. Mol. Cancer Res., 4: 729-745, 2006.

Zhao, J., Zhu, K., Lubman, D., Miller, F., Shekhar, P.V.M., Gerard, B., and Barder, T.J. Proteomic analysis of estrogen response of premalignant human breast cells using a 2-D liquid separation/mass mapping technique. Proteomics, 6: 3847-3861, 2006.

Shekhar P.V.M., Santner S, Carolin-Amirikia K., and Tait, L. Direct involvement of breast tumor fibroblasts in the modulation of tamoxifen sensitivity. Amer. J Pathol, 170:1546-1560, 2007.

Nangia-Makker, P., Tait, L, Shekhar, P.V.M., Palomino, E., Hogan, V., Funasaka, T., and Raz, A. Inhibition of breast tumor growth and angiogenesis by a medicinal herb: Ocimum gratissimum. Int J Cancer, April 16, E Pub, 2007.

Shekhar, P.V.M. and Larry Tait. Breast cancer stem cell paradigm. In: Stem Cells and Cancer" (Ed. Devon W. Parsons), Nova Science Publishers, Hauppauge, NY, pp. 47-64, 2007.

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Shijie Sheng, Ph.D., M.P.H.
Breast and Prostate Cancer/Proteases and Metastasis
Ph.D., University of Florida, 1993

Dr. Sheng’s laboratory has been interested in the biological functions and underlying molecular mechanisms of maspin is a 42 kDa novel serine protease inhibitor (serpin) with multifaceted tumor suppressive activities. To date, the consensus that maspin expression predicts a better prognosis still largely holds for breast, prostate, colon, and oral squamous cancers. Interestingly, however, more detailed analyses revealed a biphasic expression pattern of maspin in early steps of tumorigenesity and re-expression of maspin in dormant cancer metastastic revertants. These data suggest a sensitivity of maspin expression to changes of epithelial microenvironments, and a role of maspin in epithelial homeostasis. Experimental evidence consistently showed that maspin suppresses tumor growth, invasion and metastasis, induces tumor redifferentiation, and enhances tumor cell sensitivity to apoptosis. Maspin protein isolated from biological sources is a monomer which is present as a secreted, a cytoplasmic, a nuclear, as well as a cell surface-associated protein. Nuclear maspin is associated with better prognoses of cancer. It is further noted that extracellular maspin is sufficient to block tumor induced extracellular matrix degradation, tumor cell motility and invasion, whereas intracellular maspin is responsible for the increased cellular sensitivity to apoptosis. Despite these exciting developments, the mechanistic studies of maspin have proven challenging primarily due to the lack of a prototype molecular model. Although the maspin sequence has overall homologies with other members in the serpin superfamily, it does not behave like a typical serpin, i.e., non-inhibitory toward active serine proteases in solution. This novel feature is in line with the X-ray crystallographic evidence. Several of our recent studies dedicated to finding the maspin partners support a paradigm shift. In brief, intracellular maspin binds and inhibits histone deacetylase, binds and enhances the activity of glutathione s-transferase, and binds and biochemically silence heat shock protein 90. In the meantime, extracellular maspin binds and inhibits cell surface-associated zymogen form of urokinase-type plasminogen activator, binds and inhibits fibrinogen bound tissue type plasminogen activator, binds and protects the proteolytic degradation of extracellular matrix protein type I collagen.  More than a decade after the discovery of the maspin gene, our pursuit of the molecular mechanisms of maspin revealed a significant divergence of maspin from other serpins. This divergence stems from its ancestral sequence code and, accordingly, its novel “meta”-serpin structure.  The uniquely important function of maspin in development and tumor progression is likely due to its ability to target serine protease-like molecules. From an evolution point of view, the conservation of a serine protease-like catalytic center in many molecules requires the co-existence of endogenous antagonists. To this end, the activity of maspin to target serine protease-like molecules such as HDAC1 and pro-uPA may not be substituted by other serpins that have evolved to acquire higher target specificities. Thus, tumor suppressive maspin offers a unique therapeutic opportunity.

Selected Publications

Liu, J., Yin, S., Reddy, N., Spencer, C., Sheng, S.  Bax mediates the apoptosis-sensitizing effect of maspin, Cancer Res. 64: 1703-11, 2004.

Yin, S, Li, X, Meng, Y. Finley, RL Jr, Sakr, W, Yang, H, Reddy, N, and Sheng, S, Tumor Suppressive Maspin Regulates Cell Response to Oxidative Stress by Direct Interaction with Glutathione S-transferase, J. Biol. Chem. 280: 4985-96, 2005.

Yin, S, Lockett, J, Meng, Y, Biliran, HR. Jr, Blouse, G, Lin, X, Anagli, J, Reddy, N, Zhao, Z. Cher, ML, and Sheng, S.  Maspin retards cell detachment via a novel interaction with the uPA/uPAR system. Cancer Res. 66: 4173-81, 2006.

Li, X, Yin, S, Sakr, W, Meng, Y, Zhao, Z, and Sheng, S,  Endogenous inhibition of histone deacetylase 1 by tumor suppressive maspin. Cancer Res. 66: 9330-7, 2006.

Li, X, Chen, D, Yin, S, Meng, Y, Yang, H, Landis-Piwowar, KR, Li, Y, Sarkar, F, Reddy, PVG, Dou, QP, and Sheng, S,  Maspin augments proteasome inhibitor-induced apoptosis in prostate cancer cells. J. Cell. Physiol. as Rapid Communication (Epub ahead of print), 2007.

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The human estrogen receptor-alpha is succinctly described as a gligand-activated transcription factors. It changes conformation in response to the binding of endogenous hormones and exogenous ligands such as the anti-cancer drug tamoxifen; the changes in conformation lead to changes in the oligomeric state of the protein, its affinity for DNA, phosphorylation of specific serine residues by protein kinases, and alterations in the interaction with coregulator proteins that lead to changes in the transcription of specific genes. Biologically, binding to this protein and subsequent changes in the activity of this protein is responsible for many of the physiological activities of the steroid hormone 17__estradiol. Equally importantly, it is a target for the anti-cancer drugs tamoxifen and raloxifene. My laboratory is focused on understanding the conformational changes of this important protein. By understanding the conformation changes of this protein, and what drives them, drugs that produce the desired effects, but not the undesirable side effects, can be designed.

Our general approach is to identify areas likely to be involved in regulating the conformation of the protein. We then use site-directed mutagenesis to alter the identified areas, and test the functions of the mutants in a number of different assays. We supplement our bench studies with molecular modeling of the wild-type and mutated receptors. We aim to provide information that will assist in the development of drugs that selectively, and with minimal side effects, block the growth-promoting effects of estradiol, and so can be used to prevent and treat breast cancer

Selected Publications

Zhao, C., Abrams, J., and Skafar, D.F. Targeted mutation of key residues at the start of helix 12 in the hERalpha ligand-binding domain identifies the role of hydrogen-bonding and hydrophobic interactions in the activity of the protein.J. Steroid Biochem. Mol. Biol. 98:1-11, 2006.

Skafar, D.F. and Koide, S. Understanding the estrogen receptor-alpha using targeted mutagenesis.  Proceedings of the International Symposium on Steroid Hormone Receptors and Molecular Signaling, November 25-27, Trivandrum, Kerala, India.  Molecular and Cellular Endocrinology, 246:83-90, 2006.

Koide, A., Zhao, C., Naganuma, M., Abrams, J., Deighton-Collins, S., Skafar, D.F., and Koide, S. Identification of regions within the F domain of the human estrogen receptor-alpha that are important for modulating transactivation and protein-protein interactions. Molecular Endocrinology, 21:829-842, 2007.

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Guri Tzivion, Ph.D.
Breast Cancer
Ph.D., Hebrew University, Jerusalem, Israel, 1995

Dr.Tzivion's laboratory studies intracellular signaling pathways downstream of growth factor receptors involved in cell growth, cell death and longevity. There are two ongoing projects at the lab that address fundamental questions in cellular signaling: 1. Regulation of c-Raf-1 by Ras and growth factors. 2. 14-3-3 function, structure and regulation. These studies employ various molecular biology, biochemical and proteomics techniques as well as a transgenic mouse model expressing a myc-epitope-tagged 14-3-3 zeta developed at the lab. Through studying basic cellular signaling processes the research examines diverse physiological questions relating to mechanisms of cancer development and treatment. Besides the established projects, a newer third program studies the role of Foxo family transcription factors and nicotinamiadses in aging and cancer.

Selected Publications

Luo ZJ, Tzivion G, Belshaw PJ, Vavvas D, Marshall M and Avruch J. Oligomerization activates c-Raf-1 through a Ras-dependent mechanism. Nature 383:181-85, 1996.

Tzivion G, Luo ZJ and Avruch J. A dimeric 14-3-3 protein is an essential cofactor for Raf kinase activity. Nature 394:88-92, 1998.

Tzivion G, Luo ZJ and Avruch J. Calyculin A-induced vimentin phosphorylation sequesters 14-3-3 and displaces other 14-3-3 partners in vivo. JBC 275:29772-78, 2000.

Cahill CM, Tzivion G, Nasrin N, Ogg S, Dore J, Ruvkun G and Alexander-Bridges M. PI-3 kinase signaling inhibits DAF-16 DNA binding and function via 14-3-3-dependent and 14-3-3-independent pathways. JBC 276:13402-10, 2001.

Tzivion G, Shen YH, Zhu J. 14-3-3 proteins; bringing new definitions to scaffolding. Oncogene 20:6331-38, 2001.

Sathyanarayana P, Barthwal MK, Kundu CN, Lane ME, Bergmann A, Tzivion G and Rana A. Activation of the Drosophila MLK by ceramide reveals TNF-a and ceramide as agonists of mammalian MLK3. Molecular Cell 10:1527-33, 2002.

Tzivion G and Avruch J. 14-3-3 Proteins: Active Cofactors in Cellular Regulation by Serine/Threonine Phosphorylation. JBC 277:3061-64, 2002.

Shen YH, Godlewski J, Zhu J, Sathyanarayana P, Leaner V, Birrer MJ, Rana A and Tzivion G. Cross Talk between JNK/SAPK and ERK/MAPK Pathways: Sustained Activation of JNK Blocks ERK Activation by EGF. JBC 278:26715-21, 2003.

Shen YH, Godlewski J, Bronisz A, Zhu J, Comb MJ, Avruch J and Tzivion G. Significance of 14-3-3 Self-Dimerization for Phosphorylation-Dependent Target Binding. Mol Biol Cell 14:4721-33, 2003.

Zhu J, Balan V, Bronisz A, Balan K, Sun H, Leicht DT, Luo Z, Qin J, Avruch J and Tzivion G. Identification of Raf-1 S471 as a novel phosphorylation site critical for Raf-1 and B-Raf kinase activities and for MEK binding. Mol Biol Cell 16:4733-44, 2005.

Balan V, Leicht DT, Zhu J, Balan K, Kaplun A, Singh-Gupta V, Qin J, Ruan H, Comb MJ and Tzivion G. Identification of novel in vivo Raf-1 phosphorylation sites mediating positive feedback Raf-1 regulation by ERK. Mol Biol Cell 17:1141-53, 2006.

Bronisz A, Sharma SM, Hu R, Godlewski J, Tzivion G, Mansky KC and Ostrowski MC. Microphthalmia-associated transcription factor interactions with 14-3-3 modulate differentiation of committed myeloid precursors. Mol Biol Cell 17:3897-906, 2006.

Tzivion G, Singh-Gupta V, Kaplun L and Balan V. 14-3-3 proteins as potential oncogenes. Semin Cancer Biol 16:203-13, 2006.

Leicht DT, Balan V, Kaplun A, Singh-Gupta V, Kaplun L, Dobson M and Tzivion G  Raf kinases; function, regulation and role in human cancer. BBA- Mol Cell Res 1173:1196-1212, 2007.

Balan V, Miller G, Kaplun L, Balan K, Chong Z, Li F, Kaplun A, VanBerkum MFA, Arking R, Freeman DC, Maiese K and Tzivion G Life-span extension and neuronal cell protection by Drosophila nicotinamidase. PNAS, under review. 2007

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Wei-Zen Wei, Ph.D.
Breast Cancer
Ph.D., Brown University, 1978

The primary goal of this lab is to treat of prevent cancer by active vaccination. ErbB-2 (Her-2/neu) based DNA and cell vaccines have been produced to trigger Her-2 specific anti-tumor immunity. Her-2 is a transmembrane tyrosine kinase which mediates oncogenic activity and is overexpressed by several types of solid tumors including breast, ovarian, small cell lung cancer, etc. Over-expressed Her-2 is recognized by the immune system as a tumor associated antigen and an excellent target of active vaccination. Her-2 based vaccines developed in our lab are free of oncogenic activity and induce Her-2 specific immune response. Transgenic mice expressing Her-2 have been established to mimic human immune tolerance to Her-2. A powerful way to induce anti-tumor immunity in these tolerant mice is to remove regulatory T (Treg) cells before intramuscular electroporation with Her-2 DNA. Established tumors in tolerant hosts are rejected with this regimen. This potent anti-tumor immunity is accompanied by the concurrent induction of immune reactivity to self antigens such as thyroid or nuclear antigens. The immune mechanisms mediating tumor rejection and autoimmunity are being analyzed with the goal of attaining strong anti-tumor immunity with minimal autoimmunity. The most efficacious regimens can be translated into clinical trials.

Selected Publications

Shari A. Pilon, Marie P. Piechocki and Wei-Zen Wei, Vaccination with cytoplasmic ErbB-2 DNA protects mice from mammary tumor growth without anti-ErbB-2 antibody. J. Immunol. 167: 3201-3206, 2001.

Marie P. Piechocki, Shari A. Pilon and Wei-Zen Wei. Complementary anti-tumor immunity induced by plasmid DNA encoding secreted and cytoplasmic human ErbB-2. J. Immunol. 167: 3367-3374, 2001.

Rewale, S., Hrihorczuk, LM., Wei, WZ and Zemlicka, J., Synthesis and biological activity of prodrug of class I major histocompatibility peptide GILGFVFTL activated by beta-glucuronidase. .J. Med. Chem. 45: 937-943, 2002.

Shari A. Pilon, Carmen Kelly and Wei-Zen Wei Broadening of epitope recognition during immune rejection of ErbB-2 positive tumor prevents growth of ErbB-2 negative tumor. J. Immunol. 170(3):1202-1208, 2003.

Marie P. Piechocki, Ye-Shih Ho, Shari Pilon and Wei-Zen Wei, Human ErbB-2 (Her-2) transgenic mice: A model system for testing Her-2 based vaccines. J. Immunol. 171: 5787-5794, 2003.

Wei-Zen Wei, Gerald P. Morris and Yi-chi M. Kong, Anti-tumor immunity and autoimmunity: a balancing act of regulatory T cells. Cancer Immunology and Immunotherapy. 53:73-78, 2004.

Wei, WZ., "Introduction" in "Immunology of Breast Cancer", vol. 20 of "Breast Disease " series. Ed. WZ Wei and D. Lopez. IOS press, Amsterdam, The Netherlands, 2004.

Wei-Zen Wei, Jennifer B. Jacob, John F. Zielinski, Jeffrey C. Flynn, K. David Shim, Ghazwan Alsharabi, Alvaro A. Giraldo, Yi-chi M. Kong, Concurrent induction of anti-tumor immunity and autoimmune thyroiditis in CD4+CD25+ regulatory T cell depleted mice, Cancer Research, 65:8471-8478, 2005.

Jacob, J., Radkevich, O., Forni, G., Zielinski, J., Shim, D., Jones, RF., Wei.WZ., Activity of DNA vaccines encoding self or heterologous Her-2/neu in Her-2 or neu transgenic mice.  Cell Immunol. 240:96-106, 2006.

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