The MnSOD transfected cells were significantly more resistant to ionizing radiation than the non-tranfected cells. However, there was no significant difference in survival between MnSOD-minicircle and MnSOD full plasmid transfected cells. According to Dr. Greenberger, whose group is currently conducting a phase I/II clinical trial in lung cancer patients consisting of twice-weekly swallowed MnSOD for protection of the esophagus from chemoradiotherapy damage, these results suggest that minicircle DNA containing the human MnSOD transgene confers undiminished radioprotection to cells.
"Because we now can deliver MnSOD in this very small vector, we will be able to get this radioprotective enzyme more efficiently into all of the cells of the body and give patients receiving total body radiation for systemic cancers better long-term outcomes. This also has implications for the prophylactic protection of those who may be the first responders to a nuclear accident or a terrorist attack, such as a "dirty bomb," he explained.
Contact: Jim Swyers
University of Pittsburgh Schools of the Health Sciences