[论文解读] In vitro Demonstration of Cancer Inhibiting Properties from Stratified Self-Organized Micro-Discharge Plasma-Liquid Interface

Zhitong Chen, Shiqiang Zhang+3 more|arXiv (Cornell University)|Jan 6, 2017

Plasma Applications and Diagnostics参考文献 33被引用 3

一句话总结

本研究证明，分层自组织微放电等离子体-液体界面可生成独特、具有抑制癌细胞作用的活性氧和氮物种（ROS/RNS）浓度。在该界面处理液体介质可显著诱导MDA-MB-231和U87胶质母细胞瘤细胞凋亡并抑制其生长，其疗效取决于微米尺度的纤细放电结构，这些结构实现了非分层放电无法达到的异常ROS/RNS比例。

ABSTRACT

Experiments have revealed a nontrivial cancer-inhibiting capability of liquid media treated by the plasma jet capable of forming thinly stratified self-organized patterns at a plasma-liquid interface. A pronounced cancer depressing activity towards at least two kinds of human cancer cells, namely breast cancer MDA-MB-231 and human glioblastoma U87 cancer lines, was demonstrated. After a short treatment at the thinly stratified self-organized plasma-liquid interface pattern, the cancer inhibiting media demonstrate well pronounced depression and apoptosis activities towards tumor cells, not achievable without interfacial stratification of plasma jet to thin (of several um) current filaments, which therefore play a pivotal (yet still not completely clear) role in building up the cancer inhibition properties. Moreover, thinly stratified, self-organized interfacial discharge is capable to efficiently control the ROS and RNS concentrations in the cancer-inhibiting media, and in particular, abnormal ROS/RNS ratios not achievable in discharges which do not form stratified thin-filament patterns could be obtained. These results were explained in terms of interaction of thin plasma filaments of the self-organized pattern with gas and liquid, where the unusual interaction conditions (i.e., high surface-to-volume ratios etc.) cause accumulation of ROS, RNS and other species in unusual ratios and concentrations, thus forming potentially efficient anti-cancer cocktail. Our funding could be extremely important for handling the cancer proliferation problem, and hence, it should be brought to light to attract due attention of the researchers and explore the possible potential of this approach in tackling the challenging problem of high cancer-induced mortality and rising morbidity trends.

研究动机与目标

• 研究通过等离子体-液体界面处分层自组织微放电生成的等离子体处理液体介质的抗癌潜力。
• 确定纤细放电结构在增强癌细胞抑制作用中的作用。
• 量化并表征与抗癌活性相关的等离子体处理介质中ROS和RNS的浓度。
• 探讨界面分层如何导致常规放电无法实现的独特活性物种比例。
• 评估该处理介质在诱导人癌细胞系凋亡和抑制增殖方面的疗效。

提出的方法

• 操作等离子体喷射，在气-液界面形成薄层、分层且自组织的微放电图案。
• 设计等离子体-液体界面，以产生宽度在亚微米至几微米之间的微放电。
• 将液体介质短暂暴露于等离子体-液体界面，以生成活性物种（ROS/RNS）。
• 利用化学探针和光谱技术测量处理后介质中ROS和RNS的浓度与比例。
• 将人乳腺癌（MDA-MB-231）和胶质母细胞瘤（U87）细胞系暴露于处理后的介质，以评估细胞毒性与凋亡情况。
• 使用标准检测方法（如MTT、流式细胞术）定量细胞活力与凋亡，以评估抗癌效果。

实验结果

研究问题

• RQ1 分层自组织微放电等离子体-液体界面能否生成具有增强抗癌特性的液体介质？
• RQ2 纤细放电结构在调控液体中ROS与RNS浓度方面起什么作用？
• RQ3 界面分层形成的独特ROS/RNS比例是否与癌细胞凋亡增加和生长抑制相关？
• RQ4 抗癌效应是否依赖于界面处等离子体放电的结构组织？
• RQ5 该方法能否在无需直接暴露于等离子体的情况下实现对癌细胞的选择性抑制？

主要发现

• 在分层自组织微放电界面生成的等离子体处理介质可显著诱导MDA-MB-231和U87胶质母细胞瘤细胞凋亡。
• 抗癌效应强烈依赖于等离子体-液体界面处形成纤细（数微米）的电流丝，非分层放电则无此效应。
• 处理后的介质中实现了非常规的ROS/RNS比例，这些比例在传统等离子体放电中无法重现。
• 经过极短时间暴露于等离子体-液体界面后，处理介质能有效抑制癌细胞增殖。
• 抗癌活性归因于自组织纤细结构在高比表面积-体积比条件下积累活性物种。
• 结果表明，界面分层可实现一种强效且无毒的抗癌活性物质混合物在液体介质中的形成。