Single cell transcriptome profiling reveals cell-to-cell variability during the continuous treatment of tamoxifen.

The process of acquiring drug resistance in cancer cells can be understood as a process of rewiring of molecular network stimulated by the change of extracellular environment. To elucidate the cell-to-cell variability in breast cancer cells during the acquiring process of resistance to estrogen receptor antagonist, Human breast cancer MCF-7 cells were exposed to 1 uM of tamoxifen for 3, 6, and 9 weeks, and then we conducted single cell RNA sequencing. Our data showed that resistant cells to tamoxifen at week nine consists of two completely different groups; one is autophagy-activated, stem cell-like transcriptomic profile, and the other is epigenetically changed, mesenchymal type.