Masaru Hori1 Hiromasa Tanaka1 Masaaki Mizuno1 Kenji Ishikawa1 Shinya Toyokuni1 Hiroaki Kajiyama1 Fumitaka Kikkawa1

1, Nagoya University, Nagoya, , Japan

We have previously developed plasma sources with high electron density, and applied for cancer treatments [1]. We found anti-tumor effects by plasma-treated medium, and this medium with anti-tumor effects was denoted “plasma activated medium” or PAM [2]. Anti-tumor effects by PAM have been widely investigated in various cancer cell such as glioblastoma, ovarian, gastric, pancreatic, and lung cancers. We have also developed a novel plasma activated solution, plasma activated Ringer’s lactate solution (PAL) for cancer treatments [3]. We have studied intensively mechanisms of anti-tumor effects by PAM based on plasma science and molecular biological science (plasma medical science) [4].
Plasma which consists of electrons, ions, radicals, and light interacts with oxygen, nitrogen, and water in humid air to produce molecules such as nitric oxide and hydroxyl radicals, and moves into the liquid phase to generate molecules such as hydrogen peroxide (H2O2), nitrites and nitrates. These bioactive molecules trigger signaling cascades that mediate plasma-induced effects in cells. PAM influence cell signaling networks, in turn affecting gene regulatory and metabolic networks.

We have focused on the effects on cells by PAM in gene regulatory networks and signaling networks. We treated glioblastoma cells with PAM or PAL, and prepared for cell lysates to investigate gene expression levels by real-time PCR methods and activation of specific proteins by western blotting methods.
Gene expression levels related in survival and proliferation signaling were affected by PAM and PAL, but the patterns were different with each other. Activation of proteins in the survival and proliferation signaling were also affected by PAM and PAL, and the activation/deactivation patterns were different with each other. Our results suggest that these approached are useful to understand PAM or PAL-treated cells comprehensively.

Obtaining a comprehensive understanding of gene regulatory networks, signaling networks, and metabolic networks will be important to accurately determine the effects of PAM on specific cellular processes.

This work was partly supported by a Grant-in-Aid for Scientific Research on Innovative Areas “Plasma Medical Innovation” Grant No. 24108002 and 24108008.

[1] H. Tanaka, et al., Rev. Mod. Plasma Phys. , 1, 1: 3 (2017).
[2] H. Tanaka, et al., Plasma Medicine, 1, 265-277 (2013).
[3] H. Tanaka, et al., Sci Rep, 6, 36282 (2016).
[4] H. Tanaka, et al., Ieee Transactions on Plasma Science, 42, 3760-3764 (2014).