Steuer A, Wende K, Babica P, Kolb J F
Leibniz Institute for Plasma Science and Technology, Felix-Hausdorff-Strasse 2, 17489, Greifswald, Germany.
Faculty of Science, Research Centre for Toxic Compounds in the Environment (RECETOX), Masaryk University, Brno, Czech Republic.
Eur Biophys J. 2017 Sep;46(6):567-580. doi: 10.1007/s00249-017-1205-y. Epub 2017 Apr 1.
Nanosecond pulsed electric fields (nsPEFs) applied to cells can induce different biological effects depending on pulse duration and field strength. One known process is the induction of apoptosis whereby nsPEFs are currently investigated as a novel cancer therapy. Another and probably related change is the breakdown of the cytoskeleton. We investigated the elasticity of rat liver epithelial cells WB-F344 in a monolayer using atomic force microscopy (AFM) with respect to the potential of cells to undergo malignant transformation or to develop a potential to metastasize. We found that the elastic modulus of the cells decreased significantly within the first 8 min after treatment with 20 pulses of 100 ns and with a field strength of 20 kV/cm but was still higher than the elasticity of their tumorigenic counterpart WB-ras. AFM measurements and immunofluorescent staining showed that the cellular actin cytoskeleton became reorganized within 5 min. However, both a colony formation assay and a cell migration assay revealed no significant changes after nsPEF treatment, implying that cells seem not to adopt malignant characteristics associated with metastasis formation despite the induced transient changes to elasticity and cytoskeleton that can be observed for up to 1 h.
施加于细胞的纳秒级脉冲电场（nsPEFs）可根据脉冲持续时间和场强诱导不同的生物学效应。一个已知的过程是诱导细胞凋亡，目前正在研究将nsPEFs作为一种新型癌症治疗方法。另一个可能相关的变化是细胞骨架的破坏。我们使用原子力显微镜（AFM）研究了单层培养的大鼠肝上皮细胞WB-F344的弹性，以了解细胞发生恶性转化或产生转移潜能的可能性。我们发现，在用100纳秒的20个脉冲、场强为20千伏/厘米处理后的前8分钟内，细胞的弹性模量显著下降，但仍高于其致瘤对应物WB-ras的弹性。原子力显微镜测量和免疫荧光染色显示，细胞肌动蛋白细胞骨架在5分钟内发生了重组。然而，集落形成试验和细胞迁移试验均显示，nsPEF处理后没有显著变化，这意味着尽管在长达1小时内可观察到弹性和细胞骨架的诱导性短暂变化，但细胞似乎并未呈现出与转移形成相关的恶性特征。
