Antitumoral effects of combined non thermal plasma and gemcitabine treatments on a MIA PaCa-luc orthotopic pancreatic carcinoma model

Cancer of the exocrine pancreas, especially ductal adenocarcinoma, the most common pancreatic cancer, is rarely curable and has an overall survival rate of less than 4%. Moreover, chemotherapy and radiotherapy of pancreatic cancer are only, up to now, palliative treatments. New therapeutic approaches are then necessary. Recent results were obtained on the treatment of glioblastoma and colon carcinoma using non thermal plasma (NTP). They led us to assess the antitumoral effect of NTP alone or in combination with Gemcitabine, a, reference chemotherapeutic agent with radiosensitizing properties, on pancreatic cancer. Experiments were carried out using the Plasma Gun developed in GREMI both in vitro on MIA PaCa2-luc cell lines (ductal adenocarcinoma cells) then in vivo on orthotopically grafted tumor cells to induce a pancreatic carcinoma model in immune deficient nude mice. Plasma Gun NTP had an in vitro significant antitumor activity with an IC50 corresponding to 13 s exposure duration. In vivo experiments were carried out using four mouse groups: one control group, one group treated only with Gemcitabine (200mg/kg), one group treated only using the Plasma Gun, and one group treated using a combination of Gemcitabine (200mg/kg) and Plasma Gun . The striking results of these series of experiments is that, not only, the plasma treatment appeared more efficient than Gemcitabine alone, but that the combination of both led to a most effective tumor growth inhibition supporting the possible interest to use NTP in combination with a chemotherapeutical agent.