Open Access

Lyubomir Haralambiev, Josephine Jacoby, Silas Strakeljahn, Andreas Nitsch, Sander Bekeschus, Peter Hinz, Alexander Mustea, Axel Ekkernkamp, Mladen Tzvetkov, Matthias Stope

• Osteosarcoma and Ewing’s sarcoma are the most common malignant bone tumors.Conventional therapies such as polychemotherapy, local surgery, and radiotherapy improve theclinical outcome for patients. However, they are accompanied by acute and chronic side effectsthat affect the quality of life of patients, motivating novel research lines on therapeutic optionsfor the treatment of sarcomas. Previous experimental work with physical plasma operated atbody temperature (cold atmospheric plasma, CAP) demonstrated anti-oncogenic effects on differentcancer cell types. This study investigated the anti-cancer effect of CAP on two bone sarcomaentities, osteosarcoma and Ewing’s sarcoma, which were represented by four cell lines (U2-OS,MNNG/HOS, A673, and RD-ES). A time-dependent anti-proliferative effect of CAP on all cell lineswas observed. CAP-induced alterations in cell membrane functionality were detected by performinga fluorescein diacetate (FDA) release assay and an ATP release assay. Additionally, modifications ofthe cell membrane and modifications in the actin cytoskeleton composition were examined usingfluorescence microscopy monitoring dextran-uptake assay and G-/F-actin distribution. Furthermore,the CAP-induced induction of apoptosis was determined by TUNEL and active caspases assays.The observations suggest that a single CAP treatment of bone sarcoma cells may have significantanti-oncogenic effects and thus may be a promising extension to existing applications.