A method for three-dimensional coculture of cancer cells combined to any other type of cells maintained organotypically.

A three-dimensional cell coculture method is presented where cancer cells can be maintained alone or combined with other cell types in longterm culture in order to reconstitute some of the interactions between the different cell elements in tumors in vivo. The cells are accumulated by centrifugation to form 'nodules' which are cultivated on a semisolid agar medium at medium/air interface. The nodules are not mere cell aggregates, they are able to develop morphological and functional differentiation as well as tissue-like membrane junctions. Studies on short-term and long-term effects of anticancer treatments are possible and their long-term regrowth can be obtained. Especially, in nodules containing cell mixtures, the localization of the different cell types can be determined and their specific differentiation. An example showing stroma-like formations and collagen production in breast cancer cell and breast fibroblast containing nodules is presented.