ANXA5 and breast adenocarcinoma: To shed light on the mechanisms through which As2O3 induced its inhibitory effect on the survival rate of mammary adenocarcinoma cells, MCF-7 were exposed to escalated concentrations of the agent (1-5 μM) and the percentage of the annexin-V and annexin-V/PI positive cells were examined using annexin-V/PI staining assay.