Low temperature plasma: a novel focal therapy for localized prostate cancer?

Treating head and neck venous malformations with cold helium plasma electrosurgical device: A 17 patients case series

Venous malformations (VMs) are some of the most common vascular malformations. Their treatment varies from laser to sclerotherapy and surgery. For many years, radiofrequency and argon plasma devices have been used on soft tissues VMs. However, their use has been limited because of high thermal impact of nearby structures. The here described cold-helium plasma electrosurgical device carries intrinsic bio-technical advantages, as the helium plasma beam manages to move towards tissues with less impedance, such as VM vessels. The primary objective of this study was to assess if J-Plasma® could be effective on treating the superficial portion of VMs, in a single or multimodal approach. From January 2022 to January 2024, 17 patients affected by head and neck VM involving mucosa or skin were treated using J-Plasma®, in addition to sclerotherapy. More than 1 session was needed in all but 1 patient. All patients showed a progressive shrinkage of the venous chambers and thickening of the surface, while no major intraoperative and perioperative complications, such as necrosis or severe bleeding were observed. Minor complications like oedema or exfoliation were mild. All 17 patients had a complete healing of the mucosal surface one week after treatment. The grade of effectiveness and the stability of the results correlated with the complexity of the VMs. This research may serve as groundwork for future studies that may aim to explore the use of this device on other vascular malformations. LEVEL OF EVIDENCE: Case series: level 4.

Peroxiredoxin 1 modulates oxidative stress resistance and cell apoptosis through stemness in liver cancer under non-thermal plasma treatment

The role of peroxiredoxin 1 (PRDX1), a crucial enzyme that reduces reactive oxygen and nitrogen species levels in HepG2 human hepatocellular carcinoma (HCC) cells, in the regulation of HCC cell stemness under oxidative stress and the underlying mechanisms remain largely unexplored. Here, we investigated the therapeutic potential of non-thermal plasma in targeting cancer stem cells (CSCs) in HCC, focusing on the mechanisms of resistance to oxidative stress and the role of PRDX1. By simulating oxidative stress conditions using the plasma-activated medium, we found that a reduction in PRDX1 levels resulted in a considerable increase in HepG2 cell apoptosis, suggesting that PRDX1 plays a key role in oxidative stress defense mechanisms in CSCs. Furthermore, we found that HepG2 cells had higher spheroid formation capability and increased levels of stem cell markers (CD133, c-Myc, and OCT-4), indicating strong stemness. Interestingly, PRDX1 expression was notably higher in HepG2 cells than in other HCC cell types such as Hep3B and Huh7 cells, whereas the expression levels of other PRDX family proteins (PRDX 2-6) were relatively consistent. The inhibition of PRDX1 expression and peroxidase activity by conoidin A resulted in markedly reduced stemness traits and increased cell death rate. Furthermore, in a xenograft mouse model, PRDX1 downregulation considerably inhibited the formation of solid tumors after plasma-activated medium (PAM) treatment. These findings underscore the critical role of PRDX 1 in regulating stemness and apoptosis in HCC cells under oxidative stress, highlighting PRDX1 as a promising therapeutic target for NTP-based treatment in HCC.

Future aspects of plant derived bioactive metabolites as therapeutics to combat benign prostatic hyperplasia

ETHNOPHARMACOLOGICAL RELEVANCE

Benign prostatic hyperplasia (BPH), characterized by prostate enlargement due to cell proliferation, is a common urinary disorder in men over 50, manifesting as lower urinary tract symptoms (LUTS). Currently, several therapeutic options are accessible for treating BPH, including medication therapy, surgery and watchful waiting. Conventional drugs such as finasteride and dutasteride are used as 5α-reductase inhibitors for the treatment of BPH. However long-term use of these drugs is restricted due to their unpleasant side effects. Despite the range of available medical therapies, the effective treatment against BPH is still inadequate. Certain therapeutic plants and their phytochemicals have the aforementioned goals and work by regulating this enzyme.

AIM OF THE STUDY

This review aims to provide a comprehensive insight to advancements in diagnosis of BPH, modern treatment methods and the significance of ethnobotanically relevant medicinal plants as alternative therapeutics for managing BPH.

MATERIAL AND METHODS

A thorough and systematic literature search was performed using electronic databases and search engines such as PubMed, Web of Science, NCBI and SciFinder till October 2023. Specific keywords such as "benign prostatic hyperplasia", "medicinal plants", "phytochemicals", "pharmacology", "synergy", "ethnobotany", "5-alpha reductase", "alpha blocker" and "toxicology". By include these keywords, a thorough investigation of pertinent papers was assured, and important data about the many facets of BPH could be retrieved.

RESULTS

After conducting the above investigation, 104 herbal remedies were found to inhibit Phosphodiesterase-5 (PDE-5) inhibition, alpha-blockers, or 5α -reductase inhibition effects which are supported by in vitro, in vivo and clinical trial studies evidence. Of these, 89 plants have ethnobotanical significance as alpha-blockers, alpha-reductase inhibition, or PDE-5 inhibition, and the other fifteen plants were chosen based on their ability to reduce BPH risk factors. Several phytocompounds, including, rutaecarpine, vaccarin, rutin, kaempferol, β-sitosterol, quercetin, dicaffeoylquinic acid, rutaevin, and phytosterol-F have been reported to be useful for the management of BPH. The use of combination therapy offers a strong approach to treating long-term conditions compare to single plant extract drugs. Furthermore, several botanical combinations such as lycopene and curcumin, pumpkin seed oil and saw palmetto oil, combinations of extracts from Funtumia africana (Benth.) Stapf and Abutilon mauritianum (Jacq.) Medik., and Hypselodelphys poggeana (K.Schum.) Milne-Redh. and Spermacoce radiata (DC.) Sieber ex Hiern are also supported through in vitro and in vivo studies for managing BPH through recuperation in patients with chronic long-term illnesses, as measured by the International Prostate Symptom Score.

CONCLUSION

The review proposes and endorses careful utilization of conventional medications that may be investigated further to discover possible PDE-5, 5 alpha-reductase, an alpha-blocker inhibitor for managing BPH. Even though most conventional formulations, such as 5 alpha-reductase, are readily available, systemic assessment of the effectiveness and mechanism of action of the herbal constituents is still necessary to identify novel chemical moieties that can be further developed for maximum efficacy. However, there exist abundant botanicals and medicinal plants across several regions of Africa, Asia, and the Americas, which can be further studied and developed for utilization as a potential phytotherapeutic for the management of BPH.

Emerging innovations in cold plasma therapy against cancer: A paradigm shift

Cancer is one of the major causes of mortality, accounting for ∼ 9.5 million deaths globally in 2018. The spectrum of conventional treatment for cancer includes surgery, chemotherapy and radiotherapy. Recently, cold plasma therapy surfaced as a novel technique in the treatment of cancer. The FDA approval of the first trial for the use of cold atmospheric plasma (CAP) in cancer therapy in 2019 is evidence of this. This review highlights the mechanisms of action of CAP. Additionally, its applications in anticancer therapy have been reviewed. In summary, this article will introduce the readers to the exciting field of plasma oncology and help them understand the current status and prospects of plasma oncology.

Cold atmospheric plasma enhances doxorubicin selectivity in metastasic bone cancer

High-dose systemic chemotherapy constitutes a main strategy in the management of bone metastases, employing drugs like doxorubicin (DOX), related with severe side effects. To solve this issue, Cold Atmospheric Plasmas (CAP) have been proposed as potential non-invasive anti-cancer agents capable of improving the efficacy of traditional drugs. Here, we investigate the cytotoxic effects of Plasma Conditioned Medium (PCM) in combination with DOX in prostate cancer cells from bone metastases (PC-3) as well as in non-malignant bone-cells. PCM was able to enhance the cytotoxic potential of DOX both in monolayer and in a 3D bioengineered model mimicking the bone matrix. The combined treatment of PCM + DOX resulted in a profound downregulation of the redox defenses (CAT1, SOD2, GPX1) and drug resistance genes (MRP1, MDR1, BCRP1), resulting in an enhanced uptake of DOX coupled to an overload of intracellular ROS. Besides, PCM improved the cytotoxic potential of DOX interfering on the migratory and clonogenic potential of PC-3 cells. Importantly, non-malignant bone cells were unaffected by the combination of PCM + DOX. Overall, these new findings may represent a new therapeutic approach for the management of bone metastatic prostate cancer in the future.

Applications of Plasma-Activated Water in Dentistry: A Review

The activation of water by non-thermal plasma creates a liquid with active constituents referred to as plasma-activated water (PAW). Due to its active constituents, PAW may play an important role in different fields, such as agriculture, the food industry and healthcare. Plasma liquid technology has received attention in recent years due to its versatility and good potential, mainly focused on different health care purposes. This interest has extended to dentistry, since the use of a plasma–liquid technology could bring clinical advantages, compared to direct application of non-thermal atmospheric pressure plasmas (NTAPPs). The aim of this paper is to discuss the applicability of PAW in different areas of dentistry, according to the published literature about NTAPPs and plasma–liquid technology. The direct and indirect application of NTAPPs are presented in the introduction. Posteriorly, the main reactors for generating PAW and its active constituents with a role in biomedical applications are specified, followed by a section that discusses, in detail, the use of PAW as a tool for different oral diseases.

Cold Atmospheric Pressure Microplasma Pipette for Disinfection of Methicillin-Resistant Staphylococcus aureus

Microbial infections should be controlled and prevented for successful wound healing and tissue regeneration. Various disinfection methods exist that use antibiotics, ultraviolet (UV), heat, radiation, or chemical disinfectants; however, cold atmospheric pressure plasma has exhibited a unique and effective antibacterial ability that is not affected by antibiotic resistance or pain. This study develops a cold atmospheric pressure microplasma pipette (CAPMP) that outputs an Ar plasma plume through a tube with an inner radius of 180 μm for disinfection in a small area. The CAPMP was evaluated using Staphylococcus aureus and methicillin-resistant Staphylococcus aureus diluted in liquid media, spread on solid agar, or covered by dressing gauze. An increase in the treatment time of CAPMP resulted in a decrease in the number of colonies of the grown microorganism (colony forming unit) and an increase in the disinfected area for both bacteria. The disinfection ability of CAPMP was observed when the bacteria were covered with dressing gauze and was dependent on the number of gauze layers.

Dielectric barrier discharge cold atmospheric plasma: Influence of processing parameters on microbial inactivation in meat and meat products

Decontamination of meat is commonly practiced to get rid of or decrease the microbial presence on the meat surface. Dielectric barrier discharge cold atmospheric plasma (DBD-CAP) as innovative technology is a food microbial inactivation technique considered in high regard by food scientists and engineers in present times. However, cold atmospheric plasma application is at the experimental stage, due to lack of sufficient information on its mode of action in inactivating microbes, food shelf-life extensibility, whereas, the nutritional value of food is preserved. In this review, we have appraised recent work on DBD-CAP concerning the decontamination treatment of meat products, highlighting the processing value results on the efficacy of the DBD-CAP microbial inactivation technique. Also, the paper will review the configurations, proposed mechanisms, and chemistry of DBD-CAP. Satisfactory microbial inactivation was observed. In terms of DBD-CAP application on sensory evaluation, inferences from reviewed literature showed that DBD has no significant effect on meat color and tenderness, whereas in contrast, TBARS values of fresh and processed meat are affected. DBD seems economically efficient and environmentally sustainable.

Cold Atmospheric Plasma: A New Strategy Based Primarily on Oxidative Stress for Osteosarcoma Therapy

Osteosarcoma is the most common primary bone tumor, and its first line of treatment presents a high failure rate. The 5-year survival for children and teenagers with osteosarcoma is 70% (if diagnosed before it has metastasized) or 20% (if spread at the time of diagnosis), stressing the need for novel therapies. Recently, cold atmospheric plasmas (ionized gases consisting of UV-Vis radiation, electromagnetic fields and a great variety of reactive species) and plasma-treated liquids have been shown to have the potential to selectively eliminate cancer cells in different tumors through an oxidative stress-dependent mechanism. In this work, we review the current state of the art in cold plasma therapy for osteosarcoma. Specifically, we emphasize the mechanisms unveiled thus far regarding the action of plasmas on osteosarcoma. Finally, we review current and potential future approaches, emphasizing the most critical challenges for the development of osteosarcoma therapies based on this emerging technique.

Cold Atmospheric Pressure Plasma (CAP) as a New Tool for the Management of Vulva Cancer and Vulvar Premalignant Lesions in Gynaecological Oncology

Vulvar cancer (VC) is a specific form of malignancy accounting for 5–6% of all gynaecologic malignancies. Although VC occurs most commonly in women after 60 years of age, disease incidence has risen progressively in premenopausal women in recent decades. VC demonstrates particular features requiring well-adapted therapeutic approaches to avoid potential treatment-related complications. Significant improvements in disease-free survival and overall survival rates for patients diagnosed with post-stage I disease have been achieved by implementing a combination therapy consisting of radical surgical resection, systemic chemotherapy and/or radiotherapy. Achieving local control remains challenging. However, mostly due to specific anatomical conditions, the need for comprehensive surgical reconstruction and frequent post-operative healing complications. Novel therapeutic tools better adapted to VC particularities are essential for improving individual outcomes. To this end, cold atmospheric plasma (CAP) treatment is a promising option for VC, and is particularly appropriate for the local treatment of dysplastic lesions, early intraepithelial cancer, and invasive tumours. In addition, CAP also helps reduce inflammatory complications and improve wound healing. The application of CAP may realise either directly or indirectly utilising nanoparticle technologies. CAP has demonstrated remarkable treatment benefits for several malignant conditions, and has created new medical fields, such as “plasma medicine” and “plasma oncology”. This article highlights the benefits of CAP for the treatment of VC, VC pre-stages, and postsurgical wound complications. There has not yet been a published report of CAP on vulvar cancer cells, and so this review summarises the progress made in gynaecological oncology and in other cancers, and promotes an important, understudied area for future research. The paradigm shift from reactive to predictive, preventive and personalised medical approaches in overall VC management is also considered.

Cold atmospheric plasma treatment inhibits growth in colorectal cancer cells

Plasma oncology is a relatively new field of research. Recent developments have indicated that cold atmospheric plasma (CAP) technology is an interesting new therapeutic approach to cancer treatment. In this study, p53 wildtype (LoVo) and human p53 mutated (HT29 and SW480) colorectal cancer cells were treated with the miniFlatPlaSter - a device particularly developed for the treatment of tumor cells - that uses the Surface Micro Discharge (SMD) technology for plasma production in air. The present study analyzed the effects of plasma on colorectal cancer cells in vitro and on normal colon tissue ex vivo. Plasma treatment had strong effects on colon cancer cells, such as inhibition of cell proliferation, induction of cell death and modulation of p21 expression. In contrast, CAP treatment of murine colon tissue ex vivo for up to 2 min did not show any toxic effect on normal colon cells compared to H2O2 positive control. In summary, these results suggest that the miniFlatPlaSter plasma device is able to kill colorectal cancer cells independent of their p53 mutation status. Thus, this device presents a promising new approach in colon cancer therapy.

Pyruvate Plays a Main Role in the Antitumoral Selectivity of Cold Atmospheric Plasma in Osteosarcoma

Osteosarcoma (OS) is the most common primary bone tumor but current therapies still have poor prognosis. Cold Atmospheric Plasma (CAP) and Plasma activated media (PAM) have shown potential to eliminate cancer cells in other tumors. It is thought that Reactive Oxygen and Nitrogen species (RONS) in PAM are key players but cell culture media composition alters treatment outcomes and data interpretation due to scavenging of certain RONS. In this work, an atmospheric pressure plasma jet was employed to obtain PAM in the presence or absence of pyruvate and used to treat the SaOS-2 (OS) cell line or hBM-MSC healthy cells. OS cells show higher sensitivity to PAM treatment than healthy cells, both in medium with and without pyruvate, activating apoptosis, DNA damage and deregulating cellular pathways mediated by c-JUN, AKT, AMPK or STAT3. In line with previous works, lack of pyruvate increases cytotoxic potential of PAM affecting cancer and healthy cells by increasing 10–100 times the concentration of H₂O₂ without altering that of nitrites and thus decreasing CAP anti-tumor selectivity. Suitable conditions for CAP anti-cancer selectivity can be obtained by modifying plasma process parameters (distance, flow, treatment time) to obtain adequate balance of the different RONS in cell culture media.

Current trends in the treatment of liver abscesses

The paper includes the statistics of liver abscesses, etiology and related features of the diseases. The most common methods of conservative and surgical treatment of liver abscesses, currently used in surgical clinics of the Russian Federation, are presented. A small historical excursus about the existed methods of treatment is given in the paper. A comparative analysis of the currently used methods, their advantages and disadvantages is carried out. Some possible criteria for a certain method of treatment of liver abscesses are listed as well.

Cold atmospheric plasma in orthopaedic and urologic tumor therapy

Cold atmospheric plasma (CAP) is a highly reactive ionized physical state thereby provoking divers biological effects. In medical applications, CAP treatment promotes wound healing, provokes immunostimulation, and is antiseptically active. Moreover, CAP interacts with antiproliferative mechanisms suggesting CAP treatment as a promising anticancer strategy. Here we review the current state of science concerning the so far investigated CAP effects on different cancer entities in orthopaedic and urologic oncology.

Laser induced breakdown spectroscopy and acoustic response techniques to discriminate healthy and cancerous breast tissues

Laser induced breakdown spectroscopy and subsequent acoustic response during microplasma formation are employed to identify cancerous human breast tissues. The characteristic optical emissions identify Ca, Na, and Mg rich species in cancerous tissues compared to those of healthy ones. Furthermore, we show that the characteristic parameters of the microplasma, generated on the unhealthy tissues, are elevated. We report higher decibel audio signals emanating from laser induced microplasma and a subsequent audio blueshift for malignant tissues. The higher abundance of trace elements in cancerous tissues as well as higher plasma temperature and electron density in laser induced microplasma (leading to a stronger shockwave) intensify the acoustic signals.

Visible tumor surface response to physical plasma and apoptotic cell kill in head and neck cancer

The aim of the study was to learn, whether clinical application of cold atmospheric pressure plasma (CAP) is able to cause (i) visible tumor surface effects and (ii) apoptotic cell kill in squamous cell carcinoma and (iii) whether CAP-induced visible tumor surface response occurs as often as CAP-induced apoptotic cell kill. Twelve patients with advanced head and neck cancer and infected ulcerations received locally CAP followed by palliative treatment. Four of them revealed tumor surface response appearing 2 weeks after intervention. The tumor surface response expressed as a flat area with vascular stimulation (type 1) or a contraction of tumor ulceration rims forming recesses covered with scabs, in each case surrounded by tumor tissue in visible progress (type 2). In parallel, 9 patients with the same kind of cancer received CAP before radical tumor resection. Tissue specimens were analyzed for apoptotic cells. Apoptotic cells were detectable and occurred more frequently in tissue areas previously treated with CAP than in untreated areas. Bringing together both findings and placing side by side the frequency of clinical tumor surface response and the frequency of analytically proven apoptotic cell kill, detection of apoptotic cells is as common as clinical tumor surface response. There was no patient showing signs of an enhanced or stimulated tumor growth under influence of CAP. CAP was made applicable by a plasma jet, kINPen(®) MED (neoplas tools GmbH, Greifswald, Germany).

Clinical and Biological Principles of Cold Atmospheric Plasma Application in Skin Cancer

Plasma-based electrosurgical devices have long been employed for tissue coagulation, cutting, desiccation, and cauterizing. Despite their clinical benefits, these technologies involve tissue heating and their effects are primarily heat-mediated. Recently, there have been significant developments in cold atmospheric pressure plasma (CAP) science and engineering. New sources of CAP with well-controlled temperatures below 40 °C have been designed, permitting safe plasma application on animal and human bodies. In the last decade, a new innovative field, often referred to as plasma medicine, which combines plasma physics, life science, and clinical medicine has emerged. This field aims to exploit effects of mild plasma by controlling the interactions between plasma components (and other secondary species that can be formed from these components) with specific structural elements and functionalities of living cells. Recent studies showed that CAP can exert beneficial effects when applied selectively in certain pathologies with minimal toxicity to normal tissues. The rapid increase in new investigations and development of various devices for CAP application suggest early adoption of cold plasma as a new tool in the biomedical field. This review explores the latest major achievements in the field, focusing on the biological effects, mechanisms of action, and clinical evidence of CAP applications in areas such as skin disinfection, tissue regeneration, chronic wounds, and cancer treatment. This information may serve as a foundation for the design of future clinical trials to assess the efficacy and safety of CAP as an adjuvant therapy for skin cancer.

Effects of nitrogen on the apoptosis of and changes in gene expression in human lymphoma U937 cells exposed to argon-based cold atmospheric pressure plasma

Cold atmospheric pressure plasma (CAP) is known as a source of biologically active agents, such as reactive oxygen species (ROS) and reactive nitrogen species (RNS). In the present study, we examined the effects of nitrogen (N2) on the apoptosis of and changes in gene expression in human lymphoma U937 cells exposed to argon (Ar)-CAP. Enormous amounts of hydroxyl (·OH) radicals in aqueous solution were produced using Ar‑CAP generated using a 20 kHz low frequency at 18 kV with a flow rate of 2 l/min. The increase in the levels of ·OH radicals was significantly attenuated by the addition of N2 to Ar gas. On the other hand, the level of total nitrate/nitrite in the supernatant was significantly elevated in the Ar + N2-CAP‑exposed U937 cells. When the cells were exposed to Ar‑CAP, a significant increase in apoptosis was observed, whereas apoptosis was markedly decreased in the cells exposed to Ar + N2-CAP. Microarray and pathway analyses revealed that a newly identified gene network containing a number of heat shock proteins (HSPs), anti-apoptotic genes, was mainly associated with the biological function of the prevention of apoptosis. Quantitative PCR revealed that the expression levels of HSPs were significantly elevated in the cells exposed to Ar + N2-CAP than those exposed to Ar‑CAP. These results indicate that N2 gas in Ar‑CAP modifies the ratio of ROS to RNS, and suppresses the apoptosis induced by Ar‑CAP. The modulation of gaseous conditions in CAP may thus prove to be useful for future clinical applications, such as for switching from a sterilizing mode to cytocidal effect for cancer cells.

Non-thermal plasmas: novel preventive and curative therapy against melanomas?

Malignant melanoma is a very aggressive cancer with a very poor short-term prognosis once metastatic. For years, there was no efficient adjuvant therapy after surgery. Chemotherapy and immunotherapy provided hope, but not victory. Further efforts are therefore required, to find new ways to cure this disease. Physics has, once again, opened up new possibilities for treatment, through the use of non-equilibrium atmospheric pressure plasma (NEAPP). The curative potential of this technique was initially assessed on cancer cells, among which melanoma. In a recent issue, Yajima et al. use NEAPP on benign nevi, as a preventive treatment.

Low temperature plasmas as emerging cancer therapeutics: the state of play and thoughts for the future

The field of plasma medicine has seen substantial advances over the last decade, with applications developed for bacterial sterilisation, wound healing and cancer treatment. Low temperature plasmas (LTPs) are particularly suited for medical purposes since they are operated in the laboratory at atmospheric pressure and room temperature, providing a rich source of reactive oxygen and nitrogen species (RONS). A great deal of research has been conducted into the role of reactive species in both the growth and treatment of cancer, where long-established radio- and chemo-therapies exploit their ability to induce potent cytopathic effects. In addition to producing a plethora of RONS, LTPs can also create strong electroporative fields. From an application perspective, it has been shown that LTPs can be applied precisely to a small target area. On this basis, LTPs have been proposed as a promising future strategy to accurately and effectively control and eradicate tumours. This review aims to evaluate the current state of the literature in the field of plasma oncology and highlight the potential for the use of LTPs in combination therapy. We also present novel data on the effect of LTPs on cancer stem cells, and speculatively outline how LTPs could circumvent treatment resistance encountered with existing therapeutics.

Aqueous Plasma Pharmacy: Preparation Methods, Chemistry, and Therapeutic Applications

Plasma pharmacy is a subset of the broader field of plasma medicine. Although not strictly defined, the term aqueous plasma pharmacy (APP) is used to refer to the generation and distribution of reactive plasma-generated species in an aqueous solution followed by subsequent administration for therapeutic benefits. APP attempts to harness the therapeutic effects of plasma-generated oxidant species within aqueous solution in various applications, such as disinfectant solutions, cell proliferation related to wound healing, and cancer treatment. The subsequent use of plasma-generated solutions in the APP approach facilitates the delivery of reactive plasma species to internal locations within the body. Although significant efforts in the field of plasma medicine have concentrated on employing direct plasma plume exposure to cells or tissues, here we focus specifically on plasma discharge in aqueous solution to render the solution biologically active for subsequent application. Methods of plasma discharge in solution are reviewed, along with aqueous plasma chemistry and the applications for APP. The future of the field also is discussed regarding necessary research efforts that will enable commercialization for clinical deployment.

Reaction Chemistry Generated by Nanosecond Pulsed Dielectric Barrier Discharge Treatment is Responsible for the Tumor Eradication in the B16 Melanoma Mouse Model

Melanoma is one of the most aggressive metastatic cancers with resistance to radiation and most chemotherapy agents. This study highlights an alternative treatment for melanoma based on nanosecond pulsed dielectric barrier discharge (nsP DBD). We show that a single nsP DBD treatment, directly applied to a 5 mm orthotopic mouse melanoma tumor, completely eradicates it 66% (n = 6; p ≤ 0.05) of the time. It was determined that reactive oxygen and nitrogen species produced by nsP DBD are the main cause of tumor eradication, while nsP electric field and heat generated by the discharge are not sufficient to kill the tumor. However, we do not discount that potential synergy between each plasma generated component (temperature, electric field and reactive species) can enhance the killing efficacy.

Low-temperature plasma treatment induces DNA damage leading to necrotic cell death in primary prostate epithelial cells

Background:

In recent years, the rapidly advancing field of low-temperature atmospheric pressure plasmas has shown considerable promise for future translational biomedical applications, including cancer therapy, through the generation of reactive oxygen and nitrogen species.

Method:

The cytopathic effect of low-temperature plasma was first verified in two commonly used prostate cell lines: BPH-1 and PC-3 cells. The study was then extended to analyse the effects in paired normal and tumour (Gleason grade 7) prostate epithelial cells cultured directly from patient tissue. Hydrogen peroxide (H₂O₂) and staurosporine were used as controls throughout.

Results:

Low-temperature plasma (LTP) exposure resulted in high levels of DNA damage, a reduction in cell viability, and colony-forming ability. H₂O₂ formed in the culture medium was a likely facilitator of these effects. Necrosis and autophagy were recorded in primary cells, whereas cell lines exhibited apoptosis and necrosis.

Conclusions:

This study demonstrates that LTP treatment causes cytotoxic insult in primary prostate cells, leading to rapid necrotic cell death. It also highlights the need to study primary cultures in order to gain more realistic insight into patient response.