GLI1 and malignant colon neoplasm: Moreover, the drug significantly suppressed spheroid formation in CSC221 cells overexpressing Gli1/2 or ΔEN1 (an S2-cleaved but membrane-tethered form of human Notch1) but did not suppress spheroid formation in cells overexpressing both Gli1/2 and ∆EN1, suggesting that physciosporin suppresses colon cancer cell stemness through the Sonic hedgehog and Notch signaling pathways.