Controlling the propagation of primary tumors is fundamental to avoiding the epithelial to mesenchymal transition process leading to the dissemination and seeding of tumor cells throughout the body. Here we demonstrate that nanoparticles (NPs) limit the propagation of cell aggregates of CT26 murine carcinoma cells used as tumor models. The spreading behavior of these aggregates incubated with NPs is studied on fibronectin-coated substrates. The cells spread with the formation of a cell monolayer, the precursor film, around the aggregate. We study the effect of NPs added either during or after the formation of aggregates. We demonstrate that, in both cases, the spreading of the cell monolayer is slowed down in the presence of NPs and occurs only above a threshold concentration that depends on the size and surface chemistry of the NPs. The density of cells in the precursor films, measured by confocal microscopy, shows that the NPs stick cells together. The mechanism of slowdown is explained by the increase in cell-cell interactions due to the NPs adsorbed on the membrane of the cells. The present results demonstrate that NPs can modulate the collective migration of cells; therefore, they may have important implications for cancer treatment.

中文翻译：

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聚合纳米颗粒限制了细胞聚集体的集体迁移。

控制原发性肿瘤的扩散是避免上皮向间质过渡过程的基础，该过程会导致肿瘤细胞在体内扩散和播种。在这里，我们证明了纳米颗粒（NPs）限制了CT26鼠癌细胞用作肿瘤模型的细胞聚集体的繁殖。研究了这些与NPs一起孵育的聚集体在纤连蛋白包被的基质上的扩散行为。细胞在聚集体周围扩散，形成细胞单层，即前体膜。我们研究了在聚集体形成期间或之后添加NP的影响。我们证明，在两种情况下，细胞单层的扩散在NP存在下均减慢，并且仅在取决于NP大小和表面化学性质的阈值浓度以上才发生。通过共聚焦显微镜测量，前体膜中的细胞密度表明NP将细胞粘在一起。减慢的机理可以解释为由于NP吸附在细胞膜上而引起的细胞间相互作用的增加。目前的结果表明，NPs可以调节细胞的集体迁移。因此，它们可能对癌症治疗具有重要意义。