TP53 and breast cancer: Upon endocrine therapy in ER + breast cancer cell line, MCF7, a rare subpopulation of pre-adapted cells with high plasticity have been found to have district transcriptomic signatures (upregulation of genes involved in p53 signalling pathway, epithelial-mesenchymal transition (EMT), hypoxia and cell polarity) with features of dormancy as well as mixed epithelial and mesenchymal characteristics.