EPCAM and cancer: DAVID functional annotation had selected only 4 out of 16 pathways in the A549 CD166 + EpCAM + CSC subpopulation, and 3 pathways in the A549 CD166-EpCAM– non-CSC subpopulation (Table 1) that were related to cancer diseases and that involved the proteins YWHAB, YWHAQ, and YWHAZ.