ABCG2 and spindle cell hemangioma: Interestingly, the SCH cell line, which has the highest expression of ABCG2 among the cell lines tested, also displayed the lowest response to SN-38 exposure (0.004–1 μM) (Figure 8B), whereas treatment with SCO-101 alone (10–50 μM) did not affect cell viability in any cell line (Figure 8C).