. Author manuscript; available in PMC: 2021 Apr 30.

Published in final edited form as: J Med Chem. 2018 Oct 31;61(22):9908–9930. doi: 10.1021/acs.jmedchem.8b00639

Table 4.

Cytotoxicity of the 19a in Drug-Resistant Isogenic Human Cancer Cell Lines

	GI₅₀ ± SD (μM)^a
compd	parental cell line	resistant subline	resistance ratio^b
	HCT116	HCT116-siTOP1
19a	0.076 ± 0.010	0.45 ± 0.31	5.9
1	0.009 ± 0.001	0.075 ± 0.014	8.3
	DU-145	DU145-RC0.1
19a	0.018 ± 0.002	2.38 ± 0.34	132
1	0.021 ± 0.016	4.73 ± 0.68	225
	MCF-7	MCF-7/ADR
19a	0.34 ± 0.098	0.95 ± 0.35	2.8
DOX	0.15 ± 0.003	11.67 ± 1.94	77.8
	HepG2	HepG2/ADR
19a	0.30 ± 0.050	3.20 ± 0.40	10.7
DOX	0.19 ± 0.048	9.04 ± 0.14	47.6

GI₅₀ values (means ± SD) were defined as the concentrations of compounds that resulted in 50% cell growth inhibition and obtained from MTT assay. Every experiment was repeated at least three times.

Resistance ratio was calculated by dividing the GI₅₀ of the mutant cell line by the GI₅₀ of the corresponding parental cell line.