Table 4.

The sensitization potential of selenoesters against paclitaxel-resistant human breast carcinoma cell line MCF- 7/PAX. Tested compounds were applied in single dose (IC₁₀) and paclitaxel in concentration range in order to determine its concentration halving the viability (IC₅₀). Fold change was calculated as the ratio of IC₅₀ of paclitaxel and IC₅₀ of paclitaxel in the presence of IC₁₀ dose of compound.

Cpd	IC10 of compounds [µM]	IC50 [µM]	Fold change
K3	1.2	1.1 ± 0.1b	(1.4 ± 0.1)×
K4	1.8	1.1 ± 0.0b	(1.4 ± 0.1)×
K7	1.3	0.7 ± 0.0a	(2.1 ± 0.2)×
PAX	–	1.5 ± 0.0c	–

Data are expressed as the average inhibitory concentration (IC₅₀) or fold change of three repetitions with standard error of the mean (SEM). Fold change higher than 1 indicated the synergistic effect of paclitaxel and selenoesters. The statistical differences between compounds were calculated by one-way analysis of variance (ANOVA) and Duncan’s post hoc test (p ˂ 0.05), where significances were denoted by different letters (a–c).

Significant values are in [bold].