Table 3. Cytotoxicity assessed by the MTT test in HEK293. Cells (5 × 10³ mL^–1) were treated for 72 h with increasing concentrations of tested compounds. The cytotoxicity was assessed by the MTT test. IC₅₀ values were calculated by a four parameter logistic model (P < 0.05). S.D. = standard deviation. Selectivity index (SI) is defined as IC₅₀ non-tumor/tumor cell line.

Class	Compound	IC50 (μM) HEK293	Selectivity index (SI)
			PSN-1	BCPAP	LoVo
COXi, PDKi	CAD	0.09 ± 0.02	1.5	1.5	0.1
	CID	0.07 ± 0.03	0.9	0.5	0.2
HDACi, COXi	CPA	0.11 ± 0.01	1.2	1.8	2.0
	CPI	0.13 ± 0.03	0.1	1.6	0.6
	CVA	0.59 ± 0.21	4.5	59.0	0.6
	CVI	0.47 ± 0.08	6.7	0.7	13.8
HDACi, PDKi	CPD	1.56 ± 0.22	15.6	14.2	82.1
	CVD	1.98 ± 0.26	3.2	198.0	2.6
Reference	CDDP	19.62 ± 2.33	1.1	2.6	2.1