ABCG2 and cancer: In this study, 14 signaling pathways involved in calcium signaling, hedgehog signaling, cytokine–cytokine receptor interaction, regulation of actin cytoskeleton, TGF-beta signaling, cell adhesion molecules (CAMs), MAPK signaling, pathways in cancer, JAK-STAT signaling, Wnt signaling, chemokine signaling, toll-like receptor signaling, and ABC transporters were differentially enriched in the highly expressed phenotypes of LUM (Table 6, Figure 5, Figure S1).