ON REDUCING DAMAGE AND INCREASING EFFECTIVENESS OF RADIATION THERAPY AND CHEMOTHERAPY
PROFESSOR EMERITUS, SLAC,
4-5 p.m., Tuesday, 6 November 2007
School of Physics Common Room
Room 64, Old Main Building
This talk describes the use of a modified treatment sequence, i.e., radiation dose, geometry, dwell time, etc., to mitigate some of the deleterious effects of cancer radiotherapy by utilizing natural cell repair processes, i.e., adaptive response. If the bad side effects can be reduced, a more aggressive therapy can be utilized. Cells contain many mechanisms that repair damage of various types, and if not repairable, will induce apoptosis (cell death).
Data will be reviewed that support the fact that a small dose of radiation will activate damage repair genes within a cell, among these are DNA, RNA, heat, and oxidative stress repair. Once the mechanisms are fully active, they will efficiently repair the severe damage from a much larger (~100x) radiation dose.
The data ranges from experiments on specific cell cultures using microarray (gene chip) techniques to experiments on complete organisms. The suggested effect and treatment is consistent with the assumption that all radiation is harmful, no matter how small the dose. Nevertheless, the harm by large radiation exposure can be reduced.
These mechanisms need to be further studied and characterized. In particular, their time dependence needs to be understood before the proposed treatment can be truly optimized. We have carried out radiation experiments on canine cell cultures and on canine cancer patients (not test animals) at the VaTech Veterinary Hospital. Under certain situations it is also possible that low dose can mitigate the deleterious effects of chemotherapy and damage to radiation workers.
Professor Blankenbecler is an adjunct Professor of Physics at Virginia Tech and an adjunct research fellow at the Nevada Cancer Insitute.
audience is invited to meet the speaker beforehand at 3.45 p.m. over
wine and cheese in the Physics Common Room.