Quantitative in vitro characterization of transformed cell lines as a model for metastatic dissemination

Tumour invasion and metastatic dissemination depends on cell motility, a process that may be studied and quantitatively evaluated by analysing multidimensional digital images. Current methods allow to keep track of the paths followed by specific objects and perform statistical analysis on the recorded data. By adapting a set of tools, independently developed for studying cell movement, to work with multidimensional images, the motility of cells transformed by Ras and Src oncogenes has been evaluated. Fluorescent staining methods in vivo have been used to mark cells and membrane structures, in combination with optical sectioning techniques, to follow cell changes in space and time. The described procedures allow to highlight the motility features of Ras transformed fibroblasts better than Boyden chambers, a tool often used to evaluate the invasiveness of transformed cell lines in end-point assays, and allowed to understand its complexity as deriving from the combination of a variety of cellular processes, all involved, at a different extent, in the assay.