Chemical alternative for cell identification and cross-contamination detection.

Misidentification of human cell lines has previously led to confusing results during cell culture experiments. Although several enzymatic as well as molecular analysis approaches have been developed for cell-line authentication, these methods remain costly. In the present paper, we describe a simple chemical alternative based on known compound cell cytotoxicity. In addition to cisplatin, a pool of eight tamoxifen derivative compounds was used to compare the cytotoxic effects on three different breast cancer cell lines: MCF-7, T47D and MDA-MB-231. Our results show that four out of the eight cytotoxic-related compounds allowed to distinguish the different cell lines based on their IC (the half maximal inhibitory concentration) values which are cell type dependent. The remaining chemicals, particularly the most cytotoxic P15, showed close IC values for all the cell lines. Interestingly, flow cytometry experiments have identified notable differences among the three cell lines treated with P15. T47D and MDA-MB231 cells were blocked in SubG1 phase and S phase, respectively, while no significant change in cell cycle profile was noticed for MCF-7 cells. Differences were also noted at the level of caspase-3 activity and cell proliferation in P15-treated cells.