Abstract
Cell lines are used in life science research worldwide as biological surrogates. All cell lines are subject to major limitations when used as research tools, including (i) cross-contamination with other cells cultured in the same laboratory environment and (ii) evolution in vitro that renders a given cell line inappropriate as a surrogate for a specific biological hypothesis. There is ample evidence that cross-contamination or phenotypic drift of cells in culture can generate irreproducible or misleading data. A small number of scientific journals-the International Journal of Cancer being at the forefront-and funding agencies have recently moved forward to ask for obligatory cell line authentication data. The history of implementing such rules by the International Journal of Cancer exemplifies the difficulties encountered when installing mandatory quality measures in life sciences.