A Physically Triggered Cell Death via Transbarrier Cold Atmospheric Plasma Cancer Treatment

Abstract

Cold atmospheric plasma (CAP) is a near room-temperature ionized gas composed of highly reactive species. CAP also generates thermal radiation, ultraviolet radiation, and electromagnetic (EM) waves. So far, nearly all biological effects of CAP have relied on the chemical factors in CAP. Here, we first show that the EM emission from CAP can lead to the death of melanoma cells via a transbarrier contactless method. Compared with reactive species, the effect of the physical factors causes much stronger growth inhibition on a reactive species-resistant melanoma cell line B16F10. Such a physically triggered growth inhibition is due to a new cell death type, characterized by the rapid leakage of bulk solutions from the cells, resulting in cytoplasm shrinkage and bubbling on the cell membrane. The physically based CAP-triggered cell death can occur even there is a macroscale gap between the bulk CAP and cells, which includes an air gap (∼8 mm) and a dielectric material of the dish or plate (∼1 mm). Either a too large or a too small gap will inhibit such cell death. The physically triggered cellular pressure may cause the bubbling on cells, which can be inhibited in a hypotonic environment via the extracellular osmotic pressure. This study builds a foundation to use CAP as a physically based noninvasive cancer treatment.

Combination therapy of cold atmospheric plasma (CAP) with temozolomide in the treatment of U87MG glioblastoma cells

“…Attesting to the significant role of CAP emitted electromagnetic waves, is was recently revealed that CAP could cause cell death even when a physical barrier was introduced between the cells and the CAP jet. However, the role of EM waves in CAP-TMZ treatment is yet to be investigated 70 .…”

Cold atmospheric plasma cancer treatment, direct versus indirect approaches

“…130 It is promising that we may see that many new unknows about the biological impact of bulk CAP, such as potential physical effect. 131,132…”

Cold Atmospheric Plasma Changes the Amino Acid Composition of Solutions and Influences the Anti-Tumor Effect on Melanoma Cells

“…Another important reason for the stronger anti-tumor effect of direct CAP treatment could be physical. Next to RONS production, CAP also generates thermal-and ultraviolet (UV) radiation, which also have a strong impact on tumor cell behavior [54][55][56], and which are not available in the case of indirect treatment with PTS.…”