Edmund C. Chang, Ph.D.
Cancer recurrence may be due to a small sub-population of cancer cells with stem cell like properties which are not easily treated by conventional therapy. Treatments using DNA damaging agents or ionizing radiation effectively target highly-proliferative segments of the tumor, but fail to eradicate quiescent sub-populations of the tumor mass. Therefore, the objective of my research is to identify cancer cells which are resistant to radiation therapy and use lentiviral-based RNAi to dissect mechanisms necessary for DNA damage repair in these radiation-resistant cells. To formally address the cancer stem cell hypothesis, we have also developed a lentiviral barcoding strategy in conjunction with flourescence-activated cell sorting analysis as a novel strategy for cancer cell lineage tracing. We are primarily using the transplantable p53 null mouse tumor model, from which we will be characterizing the radio-sensitizing effects of gene knockdown on heterogenous populations within the tumors.
- Joined Lab: May 2007
- Positions: Postdoctoral Fellow
- Degrees: PhD., University of Illinois, Urbana-Champaign 2007 & BA., University of California, Berkeley, 1997
- Awards: Department of Defense BCRP Postdoctoral Fellowship (2009-2012)
Charn TH, Liu ET, Chang EC, Lee YK, Katzenellenbogen JA, Katzenellenbogen BS. Genome-wide dynamics of chromatin binding of estrogen receptors alpha and beta: mutual restriction and competitive site selection. Mol Endocrinol (2010) vol. 24 pp 47-59
Chang EC, TH Charn, SH Park, Helferich WG, Komm B, Katzenellenbogen JA, Katzenellenbogen BS. Estrogen Receptors alpha and beta as determinants of gene expression: influence of ligand, dose, and chromatin binding. Mol Endocrinol (2008) vol. 22 (5) pp. 1032-43
Frasor J, Chang EC, Komm B, Lin CY, Vega VB, Liu ET, Miller LD, Smeds J, Bergh J, Katzenellenbogen BS.Gene expression preferentially regulated by tamoxifen in breast cancer cells and correlations with clinical outcome. Cancer Res. 2006 Jul 15;66(14):7334-40.
Chang EC, Frasor J, Komm B, Katzenellenbogen BS.Impact of estrogen receptor beta on gene networks regulated by estrogen receptor alpha in breast cancer cells. Endocrinology. 2006 Oct;147(10):4831-42.
Blakely EA, Bjornstad KA, Chang PY, McNamara MP, Chang E, Aragon G, Lin SP, Lui G, Polansky JR.Growth and differentiation of human lens epithelial cells in vitro on matrix. Invest Ophthalmol Vis Sci. 2000 Nov;41(12):3898-907.
Chang PY, Bjornstad K A, Chang E, McNamara M, Barcellos-Hoff MH, Lin SP, Aragon G, Polansky JR, Lui GM, Blakely EA.Particle irradiation induces FGF2 expression in normal human lens cells. Radiat Res. 2000 Nov;154(5):477-84.