2022, Miebach, Lea, Freund, Eric, Cecchini, Alessandra Lourenço, Bekeschus, Sander

Reactive species generated by medical gas plasma technology can be enriched in liquids for use in oncology targeting disseminated malignancies, such as metastatic colorectal cancer. Notwithstanding, reactive species quantities depend on the treatment mode, and we recently showed gas plasma exposure in conductive modes to be superior for cancer tissue treatment. However, evidence is lacking that such a conductive mode also equips gas plasma-treated liquids to confer augmented intraperitoneal anticancer activity. To this end, employing atmospheric pressure argon plasma jet kINPen-treated Ringer’s lactate (oxRilac) in a CT26-model of colorectal peritoneal carcinomatosis, we tested repeated intraabdominal injection of such remotely or conductively oxidized liquid for antitumor control and immunomodulation. Enhanced reactive species formation in conductive mode correlated with reduced tumor burden in vivo, emphasizing the advantage of conduction over the free mode for plasma-conditioned liquids. Interestingly, the infiltration of lymphocytes into the tumors was equally enhanced by both treatments. However, significantly lower levels of interleukin (IL)4 and IL13 and increased levels of IL2 argue for a shift in intratumoral T-helper cell subpopulations correlating with disease control. In conclusion, our data argue for using conductively over remotely prepared plasma-treated liquids for anticancer treatment.

2023, Troschke-Meurer, Sascha, Zumpe, Maxi, Meißner, Lena, Siebert, Nikolai, Grabarczyk, Piotr, Forkel, Hannes, Maletzki, Claudia, Bekeschus, Sander, Lode, Holger N.

Anti-disialoganglioside GD2 antibody ch14.18/CHO (dinutuximab beta, DB) improved the outcome of patients with high-risk neuroblastoma (HR-NB) in the maintenance phase. We investigated chemotherapeutic compounds used in newly diagnosed patients in combination with DB. Vincristine, etoposide, carboplatin, cisplatin, and cyclophosphamide, as well as DB, were used at concentrations achieved in pediatric clinical trials. The effects on stress ligand and checkpoint expression by neuroblastoma cells and on activation receptors of NK cells were determined by using flow cytometry. NK-cell activity was measured with a CD107a/IFN-γ assay. Long-term cytotoxicity was analyzed in three spheroid models derived from GD2-positive neuroblastoma cell lines (LAN-1, CHLA 20, and CHLA 136) expressing a fluorescent near-infrared protein. Chemotherapeutics combined with DB in the presence of immune cells improved cytotoxic efficacy up to 17-fold compared to in the controls, and the effect was GD2-specific. The activating stress and inhibitory checkpoint ligands on neuroblastoma cells were upregulated by the chemotherapeutics up to 9- and 5-fold, respectively, and activation receptors on NK cells were not affected. The CD107a/IFN-γ assay revealed no additional activation of NK cells by the chemotherapeutics. The synergistic effect of DB with chemotherapeutics seems primarily attributed to the combined toxicity of antibody-dependent cellular cytotoxicity and chemotherapy, which supports further clinical evaluation in frontline induction therapy.

2022, Rath, Matthias, Schwefel, Konrad, Malinverno, Matteo, Skowronek, Dariush, Leopoldi, Alexandra, Pilz, Robin A., Biedenweg, Doreen, Bekeschus, Sander, Penninger, Josef M., Dejana, Elisabetta, Felbor, Ute

Cerebral cavernous malformations (CCM) are low-flow vascular lesions prone to cause severe hemorrhage-associated neurological complications. Pathogenic germline variants in CCM1, CCM2, or CCM3 can be identified in nearly 100% of CCM patients with a positive family history. In line with the concept that tumor-like mechanisms are involved in CCM formation and growth, we here demonstrate an abnormally increased proliferation rate of CCM3-deficient endothelial cells in co-culture with wild-type cells and in mosaic human iPSC-derived vascular organoids. The observation that NSC59984, an anticancer drug, blocked the abnormal proliferation of mutant endothelial cells further supports this intriguing concept. Fluorescence-activated cell sorting and RNA sequencing revealed that co-culture induces upregulation of proangiogenic chemokine genes in wild-type endothelial cells. Furthermore, genes known to be significantly downregulated in CCM3−/− endothelial cell mono-cultures were upregulated back to normal levels in co-culture with wild-type cells. These results support the hypothesis that wild-type ECs facilitate the formation of a niche that promotes abnormal proliferation of mutant ECs. Thus, targeting the cancer-like features of CCMs is a promising new direction for drug development.

2023, Troschke-Meurer, Sascha, Zumpe, Maxi, Meißner, Lena, Siebert, Nikolai, Grabarczyk, Piotr, Forkel, Hannes, Maletzki, Claudia, Bekeschus, Sander, Lode, Holger N.

Anti-disialoganglioside GD2 antibody ch14.18/CHO (dinutuximab beta, DB) improved the outcome of patients with high-risk neuroblastoma (HR-NB) in the maintenance phase. We investigated chemotherapeutic compounds used in newly diagnosed patients in combination with DB. Vincristine, etoposide, carboplatin, cisplatin, and cyclophosphamide, as well as DB, were used at concentrations achieved in pediatric clinical trials. The effects on stress ligand and checkpoint expression by neuroblastoma cells and on activation receptors of NK cells were determined by using flow cytometry. NK-cell activity was measured with a CD107a/IFN-γ assay. Long-term cytotoxicity was analyzed in three spheroid models derived from GD2-positive neuroblastoma cell lines (LAN-1, CHLA 20, and CHLA 136) expressing a fluorescent near-infrared protein. Chemotherapeutics combined with DB in the presence of immune cells improved cytotoxic efficacy up to 17-fold compared to in the controls, and the effect was GD2-specific. The activating stress and inhibitory checkpoint ligands on neuroblastoma cells were upregulated by the chemotherapeutics up to 9- and 5-fold, respectively, and activation receptors on NK cells were not affected. The CD107a/IFN-γ assay revealed no additional activation of NK cells by the chemotherapeutics. The synergistic effect of DB with chemotherapeutics seems primarily attributed to the combined toxicity of antibody-dependent cellular cytotoxicity and chemotherapy, which supports further clinical evaluation in frontline induction therapy.

2022, Wolff, Christina M., Kolb, Juergen F., Bekeschus, Sander

In modern oncology, therapies are based on combining monotherapies to overcome treatment resistance and increase therapy precision. The application of microsecond-pulsed electric fields (PEF) is approved to enhance local chemotherapeutic drug uptake within combination electrochemotherapy regimens. Reactive oxygen species (ROS) have been implicated in anticancer effects, and cold physical plasma produces vast amounts of ROS, which have recently been shown to benefit head and neck cancer patients. PEF and cold plasma technology have been linked to immunogenic cell death (ICD) induction, a regulated cell death accompanied by sterile inflammation that promotes antitumor immunity. To this end, we investigated the combined effect of both treatments regarding their intracellular ROS accumulation, toxicity, ICD-related marker expression, and optimal exposure sequence in a leukemia model cell line. The combination treatment substantially increased ROS and intracellular glutathione levels, leading to additive cytotoxic effects accompanied by a significantly increased expression of ICD markers, such as the eat-me signal calreticulin (CRT). Preconditioned treatment with cold plasma followed by PEF exposure was the most potent treatment sequence. The results indicate additive effects of cold plasma and PEF, motivating further studies in skin and breast tumor models for the future improvement of ECT in such patients.

2022, Kamionka, Julia, Matthes, Rutger, Holtfreter, Birte, Pink, Christiane, Schlüter, Rabea, von Woedtke, Thomas, Kocher, Thomas, Jablonowski, Lukasz

Objectives: Biofilm removal is the decisive factor for the control of peri-implantitis. Cold atmospheric pressure plasma (CAP) can become an effective aid due to its ability to destroy and to inactivate bacterial biofilm residues. This study evaluated the cleaning efficiency of CAP, and air-polishing with glycine (APG) or erythritol (APE) containing powders alone or in combination with CAP (APG + CAP, APE + CAP) on sandblasted/acid etched, and anodised titanium implant surface. Materials and methods: On respective titanium discs, a 7-day ex vivo human biofilm was grown. Afterwards, the samples were treated with CAP, APG, APE, APG + CAP, and APE + CAP. Sterile and untreated biofilm discs were used for verification. Directly after treatment and after 5 days of incubation in medium at 37 °C, samples were prepared for examination by fluorescence microscopy. The relative biofilm fluorescence was measured for quantitative analyses. Results: Air-polishing with or without CAP removed biofilms effectively. The combination of air-polishing with CAP showed the best cleaning results compared to single treatments, even on day 5. Immediately after treatment, APE + CAP showed insignificant higher cleansing efficiency than APG + CAP. Conclusions: CAP supports mechanical cleansing and disinfection to remove and inactivate microbial biofilm on implant surfaces significantly. Here, the type of the powder was not important. The highest cleansing results were obtained on sandblasted/etched surfaces. Clinical relevance. Microbial residuals impede wound healing and re-osseointegration after peri-implantitis treatment. Air-polishing treatment removes biofilms very effectively, but not completely. In combination with CAP, microbial free surfaces can be achieved. The tested treatment regime offers an advantage during treatment of peri-implantitis.

2023, Förster, Sarah, Niu, Yuequn, Eggers, Benedikt, Nokhbehsaim, Marjan, Kramer, Franz-Josef, Bekeschus, Sander, Mustea, Alexander, Stope, Matthias B.

Over the past 15 years, investigating the efficacy of non-invasive physical plasma (NIPP) in cancer treatment as a safe oxidative stress inducer has become an active area of research. So far, most studies focused on the NIPP-induced apoptotic death of tumor cells. However, whether NIPP plays a role in the anti-tumor immune responses need to be deciphered in detail. In this review, we summarized the current knowledge of the potential effects of NIPP on immune cells, tumor–immune interactions, and the immunosuppressive tumor microenvironment. In general, relying on their inherent anti-oxidative defense systems, immune cells show a more resistant character than cancer cells in the NIPP-induced apoptosis, which is an important reason why NIPP is considered promising in cancer management. Moreover, NIPP treatment induces immunogenic cell death of cancer cells, leading to maturation of dendritic cells and activation of cytotoxic CD8+ T cells to further eliminate the cancer cells. Some studies also suggest that NIPP treatment may promote anti-tumor immune responses via other mechanisms such as inhibiting tumor angiogenesis and the desmoplasia of tumor stroma. Though more evidence is required, we expect a bright future for applying NIPP in clinical cancer management.

2023, Miebach, Lea, Mohamed, Hager, Wende, Kristian, Miller, Vandana, Bekeschus, Sander

Survival rates among patients with pancreatic cancer, the most lethal gastrointestinal cancer, have not improved compared to other malignancies. Early tumor dissemination and a supportive, cancer-promoting tumor microenvironment (TME) limit therapeutic options and consequently impede tumor remission, outlining an acute need for effective treatments. Gas plasma-oxidized liquid treatment showed promising preclinical results in other gastrointestinal and gynecological tumors by targeting the tumor redox state. Here, carrier solutions are enriched with reactive oxygen (ROS) and nitrogen (RNS) species that can cause oxidative distress in tumor cells, leading to a broad range of anti-tumor effects. Unfortunately, clinical relevance is often limited, as many studies have forgone the use of medical-grade solutions. This study investigated the efficacy of gas plasma-oxidized Ringer’s lactate (oxRilac), a physiological solution often used in clinical practice, on two pancreatic cancer cell lines to induce tumor toxicity and provoke immunogenicity. Tumor toxicity of the oxRilac solutions was further confirmed in three-dimensional tumor spheroids monitored over 72 h and in ovo using stereomicroscope imaging of excised GFP-expressing tumors. We demonstrated that cell death signaling was induced in a dose-dependent fashion in both cell lines and was paralleled by the increased surface expression of key markers of immunogenic cell death (ICD). Nuclear magnetic resonance (NMR) spectroscopy analysis suggested putative reaction pathways that may cause the non-ROS related effects. In summary, our study suggests gas plasma-deposited ROS in clinically relevant liquids as an additive option for treating pancreatic cancers via immune-stimulating and cytotoxic effects.

2018, Pasqual-Melo, Gabriella, Gandhirajan, Rajesh Kumar, Stoffels, Ingo, Bekeschus, Sander

Melanoma is the deadliest form of cutaneous neoplasia. With a five-year survival rate of only 5–19%, metastatic melanoma presents severe challenges in clinical therapies. In addition, palliation is often problematic due to large numbers of fast growing metastasis. This calls for new therapeutic avenues targeting highly aggressive melanoma in palliative patients. One recently suggested innovative approach for eradication of topical tumor lesions is the application of cold physical plasma. This partially ionized gas emits a cocktail of reactive oxygen and nitrogen species (ROS/RNS). ROS/RNS have been shown to be a double-edged sword in fueling cancer growth at low doses but abrogating it at higher doses. The ROS/RNS output of plasma devices is tunable, and many studies have successfully decreased cancer cell growth in vitro and tumor burden in vivo. In general, increasing numbers of clinical trials suggest combination therapies to outperform monotherapies with regard to prognosis in patients. This review describes current challenges in melanoma treatment and highlights the concept of plasma therapy in experimental studies performed in melanoma research. Future perspectives are given that combine the usage of physical plasma with e.g. chemotherapy, immunotherapy, and ionizing radiation in melanoma medical oncology.

2021, Kordt, Marcel, Trautmann, Isabell, Schlie, Christin, Lindner, Tobias, Stenzel, Jan, Schildt, Anna, Boeckmann, Lars, Bekeschus, Sander, Kurth, Jens, Krause, Bernd J., Vollmar, Brigitte, Grambow, Eberhard

Background: Skin cancer is the most frequent cancer worldwide and is divided into non-melanoma skin cancer, including basal cell carcinoma, as well as squamous cell carcinoma (SCC) and malignant melanoma (MM). Methods: This study evaluates the effects of cold atmospheric pressure plasma (CAP) on SCC and MM in vivo, employing a comprehensive approach using multi-modal imaging techniques. Longitudinal MR and PET/CT imaging were performed to determine the anatomic and metabolic tumour volume over three‐weeks in vivo. Additionally, the formation of reactive species after CAP treatment was assessed by non‐invasive chemiluminescence imaging of L‐012. Histological analysis and immunohistochemical staining for Ki‐67, ApopTag®, F4/80, CAE, and CD31, as well as protein expression of PCNA, caspase‐3 and cleaved‐caspase‐3, were performed to study proliferation, apoptosis, inflammation, and angiogenesis in CAP‐treated tumours. Results: As the main result, multimodal in vivo imaging revealed a substantial reduction in tumour growth and an increase in reactive species after CAP treatment, in comparison to untreated tu-mours. In contrast, neither the markers for apoptosis, nor the metabolic activity of both tumour entities was affected by CAP. Conclusions: These findings propose CAP as a potential adjuvant therapy option to established standard therapies of skin cancer.