KRT15 and cancer: Fig 4 shows the tendencies of the 10 cancer signatures along the pseudo-stages. We also plot the expression profiles of genes along W-time in Fig C in S1 File. Only KRT15 and KRT6B are down-regulated by the EMT transition while other signatures do not vary at the E and M stages, but peak at the hybrid E/M stages. Recent experimental and theoretical evidence suggests that the hybrid E/M stages are stable phenotypes and is associated with aggressive tumor progression [49].