Allan Hildesheim, Ph.D.
|Organization:||National Cancer InstituteDivision of Cancer Epidemiology & Genetics, Infections and Immunoepidemiology Branch|
|Address:||NCI Shady GroveRoom 6E102|
Dr. Hildesheim was appointed Chief of the Infections and Immunoepidemiology Branch in 2008. He received his Ph.D. in epidemiology from The Johns Hopkins School of Hygiene and Public Health in 1991 and has been at the NCI since 1987. Dr. Hildesheim's research focuses on understanding host and viral factors involved in the pathogenesis of DNA virus-related tumors and in the evaluation of efficacy and underlying immunological mechanisms associated with licensed prophylactic HPV vaccines.
Dr. Hildesheim conducts large-scale population studies to investigate exogenous and host factors involved in the pathogenesis of DNA virus-related tumors. He investigates two groups of tumors—female gynecological cancers linked to HPV and nasopharyngeal cancer (NPC) linked to EBV. Both viral and non-viral factors hypothesized to be involved in the pathogenesis of HPV- and EBV-related cancers are examined, since infection alone is rarely sufficient for the development of cancer. Dr. Hildesheim is also the co-lead on studies to evaluate the long-term impact of HPV vaccination and the immunological mechanisms involved in long-term vaccine efficacy.
Previous studies suggested that in addition to HPV infection, important determinants of cervical disease progression may include host immune response to HPV; exogenous and behavioral factors, such as parity, smoking and oral contraceptive use; and infection with sexually transmitted agents other than HPV. Host genetic factors are also likely to play a role in cervical cancer. To further define the factors related to persistence of HPV infections and to the progression of these infections to high-grade cancer precursors, Dr. Hildesheim is the lead or co-lead on several U.S. and international case-control and cohort studies. His recent focus in this area has been on the evaluation of genetic predisposition risk factors for cervical cancer, including HLA and non-HLA genetic factors.
HPV vaccines designed to prevent infection and associated lesions associated with oncogenic HPV types 16 and 18 have been licensed in many countries. These vaccines have the potential to profoundly impact cervical cancer prevention strategies, and if applied wisely, to reach underserved populations that have historically not benefited from secondary prevention programs based on Pap smears. Dr. Hildesheim is the co-lead NCI investigator on a 7,465 women community-based HPV 16/18 vaccine trial in Costa Rica. Initiated in 2004, this trial is designed to evaluate the safety and efficacy of the HPV 16/18 vaccine, to examine broader questions of long-term population impact of vaccination, and to explore cost-effective ways in which HPV-based vaccination and screening might be applied in the future. The trial involves active follow-up of participants and includes a rich biological specimen collection component that allows for the added evaluation of numerous scientific questions of etiological and immunological interest.
Nasopharyngeal cancer has a very distinct geographic and ethnic distribution, occurring at high rates among ethnic Chinese from southeastern China and at much lower rates among Caucasians. While infection with EBV is believed to be necessary for development of the cancer, both genetic and exogenous factors are also thought to be important. Dr. Hildesheim is the lead NCI investigators on several studies of NPC in Taiwan and collaborates with investigators in China and other countries on studies of NPC. His recent focus in this area has been on the evaluation of EBV-based markers that might be useful to risk stratify individuals at high risk of familial and sporadic NPC and to better understand specific genetic factors associated with the development of NPC.