Timothy J. Jorgensen

Timothy J. Jorgensen is an Associate Professor in the Departments of Radiation Medicine, and Biochemistry & Molecular Biology. He received his Ph.D. in radiation biology from Johns Hopkins, and subsequently did a research fellowship at Harvard, studying radiation damage to DNA. His research at Georgetown has focused on cellular DNA repair. The joint goals of this work have been to both improve cancer radiotherapy by disrupting DNA repair in tumor cells, as well as to better understand the role of DNA repair in determining cancer risk. In 2003-04, he spent a sabbatical year as Visiting Scholar at Johns Hopkins, funded through a National Cancer Institute Senior Fellow Award, where he investigated the association between DNA repair genes and breast cancer risk among women in Washington County, Maryland. In 2005, he was awarded a Master of Public Health degree in cancer epidemiology. And since 2006, he has served on the National Council for Radiation Protection (NCRP), an independent body of academics that advises the federal government on setting safety limits for radiation exposure to the public.

Recent Publications:

Brewster AM, Jorgensen TJ, Ruczinski I, Yao H, Hoffman S, Thuita L, Newschaffer C, Lunn RM, Bell D, and Helzlsouer KJ: Polymorphisms of the DNA repair genes XPD (Lys751Gln) and XRCC1 (Arg399Gln and Arg194Trp): Relationship to breast cancer risk and familial predisposition to breast cancer. Breast Cancer Research and Treatment 95(1): 73-80, 2005.

Crowe SL, Movsesyan VA, Jorgensen TJ, Kondratyev A: Rapid phosphorylation of histone H2AX following ionotropic glutamate receptor activation. Europ. J. Neuroscience 23 (9): 2351-2361, 2006.

Jorgensen TJ, Kala Visvanathan K, Ingo Ruczinski I, Lucy Thuita L, and Helzlsouer KJ: Breast cancer risk is not associated with polymorphic forms of xeroderma pigmentosum genes in a cohort of women from Washington County, Maryland. Breast Cancer Res. Treat. 95:73-80, 2006.

Jorgensen TJ, Tian H, Ferguson D, Joseph IBJK, Menon K, and Frost D: Chemosensitization and radiosensitization of human lung and colon cancers by antimitotic agent, ABT-751, in athymic murine xenograft models of subcutaneous tumor growth. Cancer Chemother Pharmocol 59:725-732, 2007.

Chen J, Yenokyan G, Jorgensen TJ, Ruczinski I, Yao Y, Alani R, Lieigois N , Hoffman SC, Hoffman-Bolton J, Strickland PT, Hezlzsouer KJ, Alberg AJ: Nonmelanoma skin cancer as a marker of risk for subsequent malignancy: A community-based prospective cohort study. JNCI (in press), 2008.

National Council for Radiation Protection Scientific Committee 6-5 Commentary on “Radiation Protection and Measurement Issues Related to Cargo Scanning with High-Energy X-Rays Produced by Accelerators” (commissioned by U.S. Department of Homeland Security), (in press), 2008. [T.J. Jorgensen SC 6-5 Member, and radiation biology author.]

Jorgensen TJ, Chen K, Chasovskikh S, Roy R, Dritschilo A, and Üren A: Binding kinetics and enzymatic activity of human poly(ADP-ribose) polymerase-1 on double-stranded oligo-deoxyribinucleotide substrates. DNA Repair (submitted), 2008.

Jorgensen TJ, Helzlsouer KJ, Hoffman S, Bolton JH, Crum RM, and Visvanathan K: DNA repair genotypes associated with benign breast disease in women at high breast cancer risk. JNCI (submitted), 2008.