TOP1 and urinary bladder carcinoma: In contrast to these findings for CPTs, the FL118-sensitive bladder cancer cell lines (T24, UMUC-3) resulted in the least Top1 expression after FL118 treatment (Figure 5B,C, Figure S5), while the FL118-resistant HT1376 cell line still had a substantial level of Top1 expression after FL118 treatment (Figure 5A).