Department of Experimental Biomolecular Physics/Applied Physics, KTH-Royal Institute of Technology, AlbaNova University Center, Stockholm, Sweden.
Cytometry A. 2013 Sep;83(9):855-65. doi: 10.1002/cyto.a.22304. Epub 2013 May 8.
The ability of tumor cells to invade into the surrounding tissue is linked to defective adhesive and mechanical properties of the cells, which are regulated by cell surface adhesions and the intracellular filamentous cytoskeleton, respectively. With the aim to further reveal the underlying mechanisms and provide new strategies for early cancer diagnostics, we have used ultrahigh resolution stimulated emission depletion (STED) microscopy as a means to identify metastasizing cells, based on their subcellular protein distribution patterns reflecting their specific adhesive and mechanical properties. We have compared the spatial distribution of cell-matrix adhesion sites and the vimentin filamentous systems in a matched pair of primary, normal, and metastatic human fibroblast cells. We found that the metastatic cells showed significantly increased densities and more homogenous distributions of nanoscale adhesion-related particles. Moreover, they showed an increase in the number but reduced sizes of the areas of cell-matrix adhesion complexes. The organization of the vimentin intermediate filaments was also found to be significantly different in the metastasizing cells, showing an increased entanglement and loss of directionality. Image analysis procedures were established, allowing an objective detection and characterization of these features and distinction of metastatic cells from their normal counterparts. In conclusion, our results suggest that STED microscopy provides a novel tool to identify metastasizing cells from a very sparse number of cells, based on the altered spatial distribution of the cell-matrix adhesions and intermediate filaments.
肿瘤细胞侵袭周围组织的能力与细胞黏附及机械性能的缺陷有关，这些特性分别受细胞表面黏附及细胞内丝状细胞骨架的调节。为了进一步揭示潜在的机制，并为早期癌症诊断提供新策略，我们使用超高分辨率受激辐射耗尽（STED）显微镜，根据反映其特定黏附及机械性能的亚细胞蛋白分布模式，来识别转移细胞。我们比较了一对原发性、正常和转移性人成纤维细胞中细胞-基质黏附位点和波形蛋白丝状系统的空间分布。我们发现转移细胞的纳米级黏附相关颗粒的密度显著增加，分布更加均匀。此外，细胞-基质黏附复合物的面积数量增加，但面积减小。迁移细胞中波形蛋白中间丝的组织也存在显著差异，表现为缠结增加和方向性丧失。建立了图像分析程序，可以客观地检测和描述这些特征，并将转移细胞与正常细胞区分开来。总之，我们的结果表明，基于细胞-基质黏附及中间丝空间分布的改变，STED 显微镜为从非常少量的细胞中识别转移细胞提供了一种新的工具。
