Table 1.

IC₅₀ values of 5,6 α/β-EC for the different periods of treatment.

		24 h	48 h	72 h
JJN3	5,6 α-EC 5,6 β-EC	20 ± 2.2 31 ± 1.1	11 ± 0.4 14 ± 0.3	14 ± 0.5 7 ± 0.4
U266	5,6 α-EC 5,6 β-EC	26 ± 1.7 25 ± 0.5	31 ± 1.2 21 ± 0.4	30 ±0.8 12 ± 0.2

MM cell lines were seeded in 96-well plates at the density of 2 × 10⁴ cells per well, then treated for 24–72 h with vehicle, 5,6 α-EC or 5,6 β-EC (5–80 µg/mL). Cell viability was assessed using an MTT assay. The IC₅₀ were calculated after drawing the inhibition curves using the Excel software and verified with the CompuSyn software (www.combosyn.com/, accessed on 21 July 2021). The indicated values are means ± SD from three different assays, with triplicate samples for each culture condition.