Table 1.

IC₅₀ values of As₂S₂ in human breast cancer cell lines exposed for different time

	IC50 (µM as As2S2)
	24 h	48 h	72 h
MCF-7	15.27±0.49	8.13±1.11##	3.69±0.47##,&
MDA-MB-231	25.5±4.00	9.18±1.78##	5.37±0.12##,$

Data are the means ± SEM from at least three independent experiments.

^## P < 0.01 vs. 24 h.

^& P < 0.05 vs. 48 h.

^$ P < 0.05 vs. MCF-7 with the same exposure time.