It is important to investigate effectiveness and safety for clinical applications of new therapeutic methods. Non-thermal plasma is pretty new technology which is expected to be applied for various medical applications such as blood coagulation , wound healing , and cancer treatments . We have previously developed plasma activated medium (PAM) for cancer treatments . We have also developed plasma activated Ringer’s lactate solution (PAL) for cancer treatments . We would like to discuss effectiveness and safety of these solutions based on our accumulated knowledge through numerous studies.
PAM selectively killed glioblastoma brain tumor cells against astrocyte normal cells . Selective killing of cancer cells by PAM have been reported in not only glioblastoma, but also ovarian, pancreatic, and other cancer cells. We have reported that PAL also selectively killed glioblastoma against normal keratinocyte cells and mammary epithelial cells. These in vitro experiments are good evidence to use PAM/PAL safely.
Various in vivo experiments also demonstrated safety of PAM/PAL. For example, PAM inhibited ovarian cancer cell metastasis, resulting in prolonged survival in a mouse model, while PAM intraperitoneal injection exerted little influence on body weight . Intravitreal injection of PAM suppressed laser-induced choroidal neovascularization, while PAM injection had no effect on regular retinal vessels, nor did it show retinal toxicity . These in vivo experimental results are important evidences to use PAM effectively and safely.
To establish plasma medical science, understanding molecular mechanisms and effectiveness and safety tests are necessary. Since PAM was developed, many in vitro and in vivo experiments have demonstrated its effectiveness and safety especially in cancer treatments. Selective killing of cancer cells by PAM are good evidences for effectiveness and safety of PAM. These results suggest PAM therapy may be a promising treatment option.
This work was partly supported by a Grant-in-Aid for Scientific Research on Innovative Areas “Plasma Medical Innovation” Grant No. 24108002 and 24108008.
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