Figure 2
From: The Cell Activation Phenomena in the Cold Atmospheric Plasma Cancer Treatment
The reactive species cannot explain the cytotoxicity of a direct CAP treatment on pancreatic adenocarcinoma cell line PA-TU-8988T. (a) A direct CAP treatment caused a stronger killing effect on PA-TU-8988T cells than an indirect CAP treatment under the same experimental conditions. The direct CAP treatment was performed by treating cancer cells on a 96-well plate. These cells were immersed in 50 μL DMEM. The indirect CAP treatment was performed by treating 50 μL DMEM in a 96-well plate. The 50 μL of treated DMEM was immediate transferred to affect the growth of cancer cells in an another 96-well plate. (b) Unknown cell-based protective factors existed in the medium after the direct CAP treatment. The direct CAP treatment was performed by treating the cancer cells immersed in 55 μL DMEM on a 96-well plate. After the treatment, 50 μL of these DMEM was immediately (<30 s after the treatment) transferred to affect the cancer cells grown in a new 96-well plate. These DMEM contains the CAP-originated reactive species and all known cell-based production during the CAP treatment. In contrast, the indirect CAP treatment was performed by treating 55 μL DMEM in a 96-well plate without touching any cells. 50 μL of these DMEM was immediately (<30 s after the treatment) transferred to affect the new cancer cells grown in a new 96-well plate. These DMEM just contained the CAP-originated reactive species. All cells were cultured 3 days before the cell viability assay. All experiments were performed in triplicate and were independently repeated for at least three times. The results are shown as the mean ± standard deviation (sd).
