Molecular Mechanisms of the Efficacy of Cold Atmospheric Pressure Plasma (CAP) in Cancer Treatment

Abstract

Recently, the potential use of cold atmospheric pressure plasma (CAP) in cancer treatment has gained increasing interest. Especially the enhanced selective killing of tumor cells compared to normal cells has prompted researchers to elucidate the molecular mechanisms for the efficacy of CAP in cancer treatment. This review summarizes the current understanding of how CAP triggers intracellular pathways that induce growth inhibition or cell death. We discuss what factors may contribute to the potential selectivity of CAP towards cancer cells compared to their non-malignant counterparts. Furthermore, the potential of CAP to trigger an immune response is briefly discussed. Finally, this overview demonstrates how these concepts bear first fruits in clinical applications applying CAP treatment in head and neck squamous cell cancer as well as actinic keratosis. Although significant progress towards understanding the underlying mechanisms regarding the efficacy of CAP in cancer treatment has been made, much still needs to be done with respect to different treatment conditions and comparison of malignant and non-malignant cells of the same cell type and same donor. Furthermore, clinical pilot studies and the assessment of systemic effects will be of tremendous importance towards bringing this innovative technology into clinical practice.

Combination Treatment with Cold Physical Plasma and Pulsed Electric Fields Augments ROS Production and Cytotoxicity in Lymphoma

“…The latter play a crucial role in mediating the plasma effects in cells [3][4][5] by mediating oxidative modifications [6][7][8] to induce signaling pathways [9][10][11]. First discovered as a new tool for disinfection and wound healing [12][13][14], plasma also demonstrates cytotoxicity towards cancer cells [15][16][17]. A range of cellular responses have been found, including apoptosis, growth inhibition, cell cycle arrest, as well as cytoskeletal and mitochondrial damage [18][19][20].…”

Special Issue “Plasma Technology for Biomedical Applications”

“…The plasma action will raise ROS concentration in both cell types, but only in cancer cells this will go beyond the threshold leading to apoptosis [11]. Reactive nitrogen species are also considered to be important in determining the plasma action, although their role is less understood [12].…”

Inhibition of Angiogenesis by Treatment with Cold Atmospheric Plasma as a Promising Therapeutic Approach in Oncology

“…The medical application of CAP has already been established in wound therapy, the sterilization of medical implants and devices, and the disinfection of air [ 30 , 31 ]. Another promising application of CAP is its use in the field of oncology, since an anti-proliferative effect of CAP on cancer cells of various cancers has already been demonstrated [ 32 , 33 , 34 , 35 ]. It is believed that, among other effects, the induction of apoptosis is the main reason for the anti-proliferative effect of CAP on cancer cells [ 34 ].…”