Physical Electronics Dept.

You are invited to attend a lecture

By

Prof. Michael Keidar

(Mechanical & Aerospace Engineering, George Washington University, Washington DC)

E-mail: keidar@gwu.edu

Cold Plasma Selectivity and Application for Cancer Therapy

Plasma is an ionized gas that is typically generated in high-temperature laboratory conditions. Recent progress in atmospheric plasmas led to the creation of cold plasmas with ion temperature close to room temperature. We have demonstrated the efficacy of cold plasma in a pre-clinical model of various cancer types (long, bladder, and skin) [1]. Both in-vitro and in-vivo studies revealed that cold plasmas selectively kill cancer cells. We showed that: (a) Cold plasma application selectively eradicates cancer cells in vitro without damaging normal cells. For instance a strong selective effect was observed: 60–70% of SW900 cancer cells were detached from the plate in the zone treated with plasma, whereas no detachment was observed in the treated zone for the normal NHBE cells under the same treatment conditions. (b) Significantly reduced tumor size in vivo. Treatment of more than 10 mice showed that cold plasma ablated tumors without affecting neighboring tissues. We found that tumors of about 5mm in diameter were ablated after 2 min of a single plasma treatment. The two best known cold plasma effects, plasma-induced apoptosis and the decrease of cell migration velocity, can have important implications in cancer treatment by localizing the affected area of the tissue and by decreasing metastasic development. In addition, cold plasma treatment has affected the cancer cell cycle. In particular, cold plasma robustly arrested the G2/M – cell cycle in both carcinoma and papilloma, while normal epithelial cells (WTK) were not significantly affected. It was shown that reactive oxygen species metabolism and oxidative stress responsive genes are deregulated. We investigated the production of reactive oxygen species (ROS) with cold plasma treatment as a potential mechanism for the tumor ablation observed.

References:[1]. M. Keidar, R. Walk, A. Shashurin, P. Srinivasan, A. Sandler, S. Dasgupta , R. Ravi, R. Guerrero-Preston, B. Trink,   Cold plasma selectivity and the possibility of a paradigm shift in cancer therapy, British Journal of Cancer, Vol. 105, No. 1295-1301, 2011