Tissue culture as a hostile environment: identifying conditions for breast cancer progression studies.

The cell culture environment (substrate, atmosphere, and medium) can have a significant influence on the characteristics of cells that propagate from clinical samples. In this issue of Cancer Cell, Ince and colleagues report improved conditions for the culture of primary human breast epithelial cells. They demonstrate that, when cells cultured using the new conditions are experimentally transformed, they are more tumorigenic, form tumor xenografts that closely resemble human breast ductal adenocarcinoma, and are more metastatic compared to cells cultured under standard conditions similarly transformed. This suggests that pre-existing differences in cell culture can modulate the tumor phenotype.