Table 3. In vitro cytotoxicity of drug combinations of 1 and DOX upon incubation with HeLa, A2780adr and MIHA cells, respectively, for 72 h.

Cell lines	Compounds/drug combinations	1 at IC50/μM	DOX at IC50/μM	Total dose at IC50/μM	CI a
HeLa	1	1.91	—	1.91	—
	DOX alone	—	0.57	0.57	—
	Co-incubation ([1] : [DOX] = 7 : 1)	0.74	0.11	0.85	0.57
	NC1	0.62	0.09	0.71	0.48
A2780adr	1	1.51	—	1.51	—
	DOX alone	—	0.68	0.68	—
	Co-incubation ([1] : [DOX] = 7 : 1)	0.85	0.12	0.97	0.75
	NC1	0.53	0.08	0.61	0.47
MIHA	1	14.49	—	14.49	—
	DOX alone	—	0.10	0.10	—
	Co-incubation ([1] : [DOX] = 7 : 1)	0.57	0.08	0.65	0.86
	NC1	3.24	0.46	3.80	4.87

^aCombination index determined by CompuSyn.