Table 2. Cytotoxic activity of melphalan and topotecan on endothelial cell types after conventional and metronomic treatment.

	Topotecan			Melphalan
Cell line	Conventional IC50 (nM)	Metronomic IC50 (nM)	IC50 Ratio	Conventional IC50 (μM)	Metronomic IC50 (μM)	IC50 Ratio
HUVEC	32.5 (29.4–42.8)	1.4a (1.3–2.0)	22.9	43.2 (39.8–55.3)	2.0a (1.8–2.6)	21.6
EPC	35.8c (32.9–53.2)	2.0a,c (1.9–3.7)	17.6	66.7b (63.9–77.5)	7.5a, b (7.0–9.9)	8.9

Data are shown as median value of 3 experiments (range).

^a p<0.05 compared to conventional treatment;

^b p<0.05 compared between cell types under the same treatment schedule;

^c p>0.05 compared between cell types under the same treatment schedule.