Biochemistry and Molecular Biology
I received my Ph.D. from the University of Virginia, Department of Biochemistry, at the School of Medicine. My work with Dr. Clive Bradbeer was on vitamin transport in bacteria. My post-doctoral work was at University of Maryland, Baltimore County in the area of coated vesicles with Dr. Tom Roth and at the Johns Hopkins University in the area of tumor biology with Dr. Jerry Hart. While at Hopkins my work on the role of cell surface glycosylation in tumor metastasis led to my subsequent staff position at the NIH (National Institute on Aging) where I focused on tumor angiogenesis. My academic appointment at the University of Maryland is in the Department of Pathology with an affiliation in the Program in Oncology at the Marlene and Stewart Greenebaum Cancer Center. I have a joint appointment in the Department of Biochemistry & Molecular Biology. In addition to my research programs in angiogenesis and breast cancer biology I also direct the Advanced Cancer Biology course in the Molecular Medicine program and participate in Cell and Molecular Biology clinical conferences for medical students.
My laboratory has studied how endothelial cells contribute to tumor vascular formation and what mechanisms regulate endothelial cell proliferation, survival, and differentiation, which may promote angiogenesis. The long-term goal is to exploit these mechanisms for therapeutic intervention. We have developed a variety of in vitro and in vivo assays to quantify some of the essential steps in angiogenesis including endothelial cell migration, invasion, and differentiation. These approaches have proven useful in screening and characterizing chemotherapeutic drugs that function as both anti-angiogenic and anti-tumor agents. Our in vivo quantitative assay for angiogenesis has been used by many academic research institutions and pharmaceutical companies to test anti-angiogenic drugs. We used this method to discover a new factor – the DNA-binding protein RUNX2 – as a potent regulator of angiogenesis. RUNX2 is expressed in the neovasculature and may regulate the expression of downstream genes involved in EC migration, proliferation, and survival including proteases (MT1MMP, MMP13, MMP9), angiogenic factors (VEGF), and matrix molecules (bone sialoprotein, osteopontin). We have shown that insulin-like growth factor (IGF)-1 receptor-selective or VEGF receptor-selective kinase antagonists inhibit RUNX2 expression and reduce EC survival and that RUNX2 DNA-binding activity depends on cell cycle-specific phosphorylation of RUNX2 by the cyclin-dependent kinase cdk1 at a unique serine residue in the C-terminus of the protein. We recently found that nutrient levels and glucose-mediated autocrine IGF-1 secretion and IGFR phosphorylation regulate RUNX2 activity. Inhibition of RUNX2 activity in hyperglycemia is mediated by aldose reductase (AR) expression (sorbitol pathway) and production of reactive oxygen species. Further, we have developed a high-throughput DNA binding ELISA method to measure RUNX2 activity that could be used for the rapid screening of anti-angiogenic factors.
Breast Cancer Research
We have found that RUNX2 promotes oncogenic transformation through its direct interaction with the coactivator protein, Yap, which is known to associate with proto-oncogenes of the c-src family. These studies and the ability to screen chemical databases by computer-assisted drug design (CADD) methods led to the discovery that one of the vitamin D3 prohormones (cholecalciferol) was a direct regulator of RUNX2 DNA binding. We are currently testing these and other compounds for their ability to interfere with growth in suspension, metastasis in mice, and breast cancer progression using epithelial-mesenchymal transition markers. Using high-through-put screening assays to optimize their activity, these compounds will be retested in animal models and, eventually, will be proposed for clinical trials.
||Endothelial cell wound healing is regulated by aldose reductase (AR) in hyperglycemia. EC cultured in euglycemia (5mM) undergo efficient wound healing but in hyperglycemia (25mM) wound healing is only possible after siRNA-mediated knockdown of AR. |
||Subnuclear localization of RUNX2 in response to glucose. Endothelial cells were treated with 5mM glucose and RUNX2 (visualized with specific antibodies) was found within focal subnuclear regions 4 hours later. This localization was dependent on glucose-mediated phosphorylation of RUNX2 at a specific cyclin-dependent kinase site.|
|| Computer-aided drug design (CADD) methods and quantitiative DNA-binding assays identified putative interacting molecules (aqua), which fit between the wing (red), tail (purple), and adjacent (yellow) domains of the RUNX DNA-binding domain.|
- Anglin, I. and Passaniti, A. (2004) Runx protein signaling in human cancers. Cancer Treat Res 119:189-215.
- Sun, L., Vitolo, M.I., Qiao, M., Anglin, I.E., and Passaniti, A. (2004) Regulation of TGFß-mediated growth inhibition and apoptosis by RUNX2 isoforms in endothelial cells. Oncogene 23:4722-34.
- Qiao, M., Shapiro, P., Fosbrink, Rus, H., Kumar, R., and Passaniti, A. (2006) Cell Cycle-dependent Phosphorylation of the RUNX2 Transcription Factor by Cdc2 Regulates Endothelial Cell Proliferation. J. Biol. Chem. 281:7118-28.
- Sun L, Hui A-M, Su Q, Vortmeyer A, Kotliarov Y, Pastorino S, Passaniti A, Menon J, Bailey R, Rolsenblum M, Mikkelson T, Fine HA. (2006) Neuronal and Glioma-Derived Stem Cell Factor Induces Angiogenesis within the Brain. Cancer Cell 9:287-300.
- Vitolo, M.I., Anglin, I.E., Mahoney, W., Renoud, K.J., Gartenhaus, R.B., Bachman, K.E., and Passaniti, A. (2007) The RUNX2 Transcription Factor Cooperates With the YES-associated Protein, YAP65, to Promote Cell Transformation Cancer Biol Ther 6: 856-863.
- D’Souza, DR, Salib, M, Bennett, J, Mochin-Peters, M, Asrani, K, Goldblum, SE, Renoud, KJ, and Passaniti, A (2009) Hyperglycemia regulates RUNX2 activation through the aldose reductase polyol pathway. J Biol Chem, 284: 17947-17955.
- Zhang, Y., Ali, T.Z., Zhou, H., D’Souza, D.R., Lu, Y., Jaffe, J., Liu, Z., Passaniti, A., and Hamburger, A.W. (2010) ErbB3 binding protein 1 represses metastasis-promoting gene anterior gradient protein 2 in prostate cancer. Cancer Res. 70:240-8.
- D’Souza, DR, Girnun, G., Pierce, A., and Passaniti, A. (2010) Glucose metabolism, transcriptional regulation, and angiogenesis. Curr. Topics Biochem. Res. 11(2): 41-55.
- Hyun, SW, Anglin, IE, Liu, A, Yang, S, Sorkin, JD, Lillehoj, E, Tonks, NK, Passaniti, A, and Goldblum, SE (2011) Diverse Injurious Stimuli Reduce Protein Tyrosine Phosphatase-μ Expression and Enhance Epidermal Growth Factor Receptor Signaling in Human Airway Epithelia. Exp Lung Res., 37(6):327-343.
- Cross, AS, Hyun, SW, Feng, C, Liu,, A, Nguyen, C, Zhang, L, Twaddell, WS, Passaniti, A, Lillehoj, EP, Puchè, AC, Huang, W, Wang, L-X, and Goldblum, SE (2012) NEU1 and NEU3 sialidase activity expressed in human lung microvascular endothelia: NEU1 restrains endothelial cell migration whereas NEU3 does not. J. Biol. Chem. 287(19):15966-80
- Pierce, AD, Anglin, IE, Vitolo, MI, Mochin, MT, Underwood, KF, Goldblum, SE, Kommineni, S, and Passaniti, A. (2012) Glucose-activated RUNX2 phosphorylation promotes endothelial cell proliferation and an angiogenic phenotype. J. Cell. Biochem. 113(1):282-92
- Underwood, K.F., D’Souza, D.R., Pierce, A.D., Mochin, M.T., Kommineni, S., Bennett, J., Choe, M., Gnatt, A., Habtemariam, B., MacKerell, A., and Passaniti, A. (2012) Regulation of RUNX2 transcription factor-DNA interactions and cell proliferation by Vitamin D3 (cholecalciferol) prohormone activity. J. Bone Min. Res. 27(4):913-25.
- Di Rosa, M., Malaguarnera, M., Zanchi, A., Passaniti, A., and Malaguarnera, L. (2013) Vitamin D3 Insufficiency and Colorectal Cancer. Crit Rev Oncol. Hematol. 88(3):594-612.
- Underwood, K.F., Mochin, M.T., Brusgard, J.L., Choe, M., Gnatt, A., and Passaniti, A. (2013) A quantitative DNA-binding assay to study protein:DNA interactions, discover transcriptional regulators of gene expression, and identify novel anti-tumor agents. J Vis Exp, Epub ; 2013, Aug 31 (78).
- Brusgard, J.L. and Passaniti, A. (2013) “RUNX2 transcriptional regulation in development and disease” in Nuclear Signaling Pathways and Targeting Transcription in Cancer; Series Title: Cancer Drug Discovery and Development; edited by R. Kumar; Springer, New York/Heidelberg.