As an indirect application of cold atmospheric plasma, the use of plasma-activated solutions has recently attracted significant attention for intracavity tumor perfusion therapy. Here, an underwater plasma-bubble reactor with three discharge modes was applied to activate a cell culture medium, with the aim of inhibiting the growth of bladder cancer T24 cells in vitro. The results showed that although the reactive species in cell culture medium generated by the underwater bubble plasma varied between the dielectric barrier discharge (DBD) mode, spark mode, and hybrid mode, the plasma-activated cell culture medium (PAM) corresponding to all three discharge modes effectively decreased the viability of T24 cells. However, after co-culturing the PAM-pretreated T24 cells with normal T24 cells, it was observed that normal T24 cells were not affected by either the DBD or spark mode; however, the hybrid mode PAM-pretreated T24 cells further induced inactivation and apoptosis of normal T24 cells. Further studies suggested that the aqueous reactive species generated by the underwater bubble plasma in hybrid mode not only induced the apoptosis of T24 cells directly but also triggered PAM-pretreated T24 cell-derived exosome-mediated anticancer activity toward cancer cells. These results may provide a strategy for enhancing the anticancer extent and effect of PAM as well as advancing its clinical application.

中文翻译：

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混合等离子体气泡激活介质诱导的抗癌传播作用


作为冷大气等离子体的间接应用，等离子体激活溶液的使用最近在腔内肿瘤灌注治疗中引起了极大的关注。这里，采用具有三种放电模式的水下等离子体气泡反应器来激活细胞培养基，目的是在体外抑制膀胱癌T24细胞的生长。结果表明，尽管水下气泡等离子体在介质阻挡放电（DBD）模式、火花模式和混合模式下产生的细胞培养基中的反应物种有所不同，但三种模式对应的等离子体激活细胞培养基（PAM）放电模式有效降低了T24细胞的活力。然而，将PAM预处理的T24细胞与正常T24细胞共培养后，观察到正常T24细胞不受DBD或spark模式的影响；然而，混合模式PAM预处理的T24细胞进一步诱导正常T24细胞失活和凋亡。进一步的研究表明，水下气泡等离子体以混合模式产生的水性反应物质不仅直接诱导T24细胞凋亡，而且还触发PAM预处理的T24细胞衍生的外泌体介导的针对癌细胞的抗癌活性。这些结果可能为增强PAM的抗癌程度和效果以及推进其临床应用提供策略。