Table 3.

Effects of phytol and heptacosane on intracellular accumulation of doxorubicin in HL-60 and HL-60R cell lines. The cells were treated with phytol, heptacosane (hepta) alone and in combination, or verapamil. After 24 h of incubation, doxorubicin (doxo) was added at different times. The intracellular accumulation of doxorubicin was measured by flow cytometric analysis. The results are presented as percentage of fluorescence intensity (means ± standard error of three experiments).

	Fluorescence %
Treatment	HL-60	HL-60R
Control	0.05 ± 0.03	0.05 ± 0.03
doxo 1 µg/mL 30 min	98.4 ± 0.42 *	7.85 ± 0.10 *
doxo 1 µg/mL 1 h	99.9 ± 0.07 *	9.80 ± 0.14 *
doxo 1 µg/mL 2 h	100 ± 0.0 *	21.8 ± 0.14 *
phytol 25 µg/mL	0.05 ± 0.03	0.05 ± 0.03
heptacosane 50 µg/mL	0.15 ± 0.03	0.25 ± 0.03
phytol 25 µg/mL + heptacosane 50 µg/mL	0.15 ± 0.03	0.05 ± 0.03
verapamil 10 µM	0.05 ± 0.02	0.05 ± 0.03
phytol 25 µg/mL + doxo 1 µg/mL 30 min	99.7 ± 0.12 *	4.70 ± 0.20 *
phytol 25 µg/mL + doxo 1 µg/mL 1 h	99.9 ± 0.03 *	10.8 ± 0.90 *
phytol 25 µg/mL + doxo 1 µg/mL 2 h	100 ± 0.0 *	17.1 ± 1.80 *
heptacosane 50 µg/mL + doxo 1 µg/mL 30 min	98.9 ± 0.67 *	31.0 ± 0.70 *,a
heptacosane 50 µg/mL + doxo 1 µg/mL L h	100 ± 0.0 *	49.6 ± 0.25 *,a
heptacosane 50 µg/mL + doxo 1 µg/mL 2 h	100 ± 0.0 *	71.7 ± 0.12 *,a
phytol 25 µg/mL + hepta 50 µg/mL + doxo 1 µg/mL 30 min	99.9 ± 0.03 *	8.35 ± 0.10 *
phytol 25 µg/mL + hepta 50 µg/mL + doxo 1 µg/mL 1 h	100 ± 0.0 *	19.6 ± 0.30 *,a
phytol 25 µg/mL + hepta 50 µg/mL + doxo 1 µg/mL 2 h	100 ± 0.0 *	39.2 ± 0.57 *,a
verapamil 10 µM + doxo 1 µg/mL 30 min	99.5 ± 0.35 *	58.7 ± 0.53 *,a
verapamil 10 µM + doxo 1 µg/mL 1 h	99.0 ± 0.70 *	70.8 ± 0.57 *,a
verapamil 10 µM + doxo 1 µg/mL 2 h	100 ± 0.0 *	98.0 ± 0.70 *,a

* p < 0.01, vs. the control. ^a p < 0.01 represent significant differences among the treatments in combination with phytol or heptacosane or verapamil compared to doxorubicin alone for the same time (one-way ANOVA followed by Tukey’s test).