Nazir Barekzi

Dose-dependent killing of leukemia cells by low-temperature plasma

The effect of low-temperature atmospheric pressure plasma towards the progression of cancerous human T-cell leukemia cells was investigated. The plasma pencil, which utilizes short duration high voltage pulses, was used to generate a low-temperature plasma (LTP) plume in ambient air. Our data showed that cell morphology and cell viability were affected in a dose-dependent manner after treatment with LTP. The outcome of this study revealed that the effect of plasma exposure was not immediate, but had a delayed effect and increasing the time of plasma exposure resulted in increased leukemia cell death.

Evaluation of the effects of a plasma activated medium on cancer cells

The interaction of low temperature plasma with liquids is a relevant topic of study to the field of plasma medicine. This is because cells and tissues are normally surrounded or covered by biological fluids. Therefore, the chemistry induced by the plasma in the aqueous state becomes crucial and usually dictates the biological outcomes. This process became even more important after the discovery that plasma activated media can be useful in killing various cancer cell lines. Here, we report on the measurements of concentrations of hydrogen peroxide, a species known to have strong biological effects, produced by application of plasma to a minimum essential culture medium. The activated medium is then used to treat SCaBER cancer cells. Results indicate that the plasma activated medium can kill the cancer cells in a dose dependent manner, retain its killing effect for several hours, and is as effective as apoptosis inducing drugs.

Killing adherent and nonadherent cancer cells with the plasma pencil

The application of low temperature plasmas in biology and medicine may lead to a paradigm shift in the way various diseases can be treated without serious side effects. Low temperature plasmas generated in gas mixtures that contain oxygen or air produce several chemically reactive species that have important biological implications when they interact with eukaryotic or prokaryotic cells. Here, a review of the effects of low temperature plasma generated by the plasma pencil on different cancerous cells is presented. Results indicate that plasma consistently shows a delayed killing effect that is dose dependent. In addition, there is some evidence that apoptosis is one of the pathways that leads to the death of the cells, indicating that plasma initiates cell signaling pathways.

Fibroblast Cell Morphology Altered by Low-Temperature Atmospheric Pressure Plasma

Low-temperature atmospheric pressure plasmas (LTAPPs) have garnered great scientific interest in recent years because of their chemically reactive properties. The LTAPP is currently being studied for potential applications in the field of plasma medicine including, but not limited to, wound healing and cancer therapy. In this paper, images of fibroblast cells exposed to different treatment times of LTAPP are presented. The results reveal the morphological cell changes associated with LTAPP treatment and indicate the potential use of LTAPP to alter physical attributes of mammalian cells.

Effects of growth medium treated by plasma pencil on the viability of scaber cancer cells

Low temperature plasma (LTP) generates biologically tolerable gas discharges, suitable for the treatment of biological tissues1. In recent years extensive research has been done on the biomedical applications of LTP including bacteria inactivation and cancer cell treatment.

Images of SCaBER Cells Treated by a Low Temperature Plasma Jet

Squamous cell carcinoma of the bladder is a rare type of bladder cancer that forms as a result of chronic irritation of the epithelial lining of the bladder. The cell line used in this paper is SCaBER (ATCC HTB3) derived from squamous cell carcinoma of the human urinary bladder. Current treatments of bladder cancer include surgery, radiation, and chemotherapy. However, the cost of these treatments, potential toxicity of the chemotherapeutic agents, and systemic side-effects warrant an alternative to current cancer treatment. In this paper, we present images of SCaBER cells treated by the plasma pencil, a device that generates a low temperature plasma plume at atmospheric pressure. The images show that after plasma treatment of only a few minutes substantial killing of SCaBER cells occur and that the cells die in a delayed manner, postplasma treatment.

Effects of aged PAM on cancer cells

The study of the effects of low temperature plasma (LTP) on cancer cells, in vitro and in vivo, is today one of the most active research areas of plasma medicine. Here, we study the interaction of LTP with cancer cells which were grown overnight and then seeded into MEM (minimal essential medium) growth culture treated by the plasma pencil at different exposure times. Plasma activated media (PAM) proved to be very effective in killing cancer cells. In our study we used “aged” PAM for different lengths of time to determine how long the treated media can be stored and still maintain its potency against cancerous cells. We found that fresh PAM (not aged) is most potent, but PAM produced by 4 minutes exposure to LTP and aged for up to 8 hours was still able to induce cell killing. Cell viability was determined immediately after treatment and at various times (hours/days) post plasma exposure, by Trypan Blue exclusion assay. The pH of the medium was monitored by a pH meter at various exposure times. Our measurements showed that buffered PAM maintained a stable pH value and therefore acidification of the media was not an issue. We hypothesize that it was the long lived solvated oxygen reactive species and nitrogen reactive species and their reaction by-products in the media that are responsible for the observed effects.

Inactivation pathways of reactive species generated by low temperature atmospheric pressure plasma

Summary form only given. Non thermal atmospheric gas plasmas have been exploited in biology, medicine, dentistry, and material science as a novel technology for health care. The unique enhanced helium gas-phase chemistry of the plasma plume is obtained when the electrons undergo collisions with the background gas and facilitate the formation of radical and metastable states. As a result, the plasma does not cause any thermal damage, since the heavy species such as the ions and neutrals remain within the biologically tolerant temperature regime1. The production of different reactive species such as metastable helium atoms help produce short-lived and long-lived reactive species (O, O 2 , O 2 −, O 3 , OH, NO, and NO 2 ) 2 when air molecules mix with the plume.

Low temperature atmospheric pressure plasma kills leukemia cells

Summary form only given. Acute lymphoblastic leukemia (ALL) is one of the most common cancers diagnosed in children1. Breakthroughs such as tyrosine kinase inhibitors and other targeted treatments have increased overall patient survivability. However, chemotherapeutic agents can lead to acquired molecular resistance resulting in recurrent tumor tissue, severe toxicity in non-tumor tissues, and systemic side-effects. In order to circumvent these negative attributes of cancer treatment regimes, our work studies the effects of low temperature atmospheric pressure plasma on a cell line of human T-cell acute lymphoblastic leukemia cells.