Tumor cells exhibit two main different migration strategies when invading in 3D environment, i. e. mesenchymal migration and amoeboid migration. This review summarizes the internal reasons and characteristics on various modes of migration adaptation to the microenvironment, and the molecular mechanisms in particular environment where they are mutually interchangeable. A study of the mechanisms that may possibly trigger mesenchymal-amoeboid transition/amoeboid-mesenchymal transition help us to understand the change and the plasticity in the migration strategies of tumor cells. These are important for the development of a cancer treatment, which would efficiently suppress tumor cell invasiveness.
Cell Movement ; physiology ; Extracellular Matrix ; pathology ; Humans ; Integrins ; physiology ; Neoplasm Invasiveness ; Neoplasm Metastasis ; physiopathology

Objective To explore the influence of integrin redistribution on hepatoma cell alignment and migration and the influence of cytoskeleton reassembly on integrin redistribution by the method of mechanical loading unloading and fibronection(FN) coating. Method By using immuneofluescence staining, cofocal laser scanning microscopy and quantitative morphological analysis, integrin distribution change and crtoskeleton assembly adjustment were observed and the deformation of cell movement was tested and analyzed quantitatively. Results (1) cells with different forms have different integrin expressions and distribution features. The β1 integrin expression for spreading cells was higher than that for round (nonspreading) cells. For spreading cells, the strongest staining was found towards the attachment surface. While for round (nonspreading) cells, the integrin staining on the free surface towards medium was stronger than that towards the attachment surface. (2) After 5 hours of mechanical stretch, the β1 integrin expression for both spreading and round cells increased, and distribution peaks towards the attachment surface broadened. At 1 hour after unloading, the β1 integrin expression decreased and the distribution of integrin staining showed the tendency of dispersion, especially for round cells. (3) After coating the substrates with FN, the β1 integrin expression increased. The integrin staining for either spreading or round cells was more towards the attachment surface to reduce the migration of hepatoma cells. 4) After 5 hours of mechanical stretch, 60% of cells showed their orientation of major axes distributed between 70°～110° towards the stretching direction, and the cytoskeleton aligned vertically to the stretching direction. Cytoskeletons were found significantly depolymerized at 1 hour of unloading. Conclusions The change of integrin distribution is affected by cytoskeleton aligned and the number of ligand. The distribution feature of the whole integrin expression on the surface of individual round cells is related to their stronger invasion and metastasis capability.