H2AX and breast carcinoma: In vitro evaluations included stability assays, cellular uptake (flow cytometry), cytotoxicity (MTT assay), mitochondrial membrane potential (JC-1 staining), apoptosis (Annexin V/PI), DNA damage (γ-H2AX immunofluorescence), and cell cycle analysis in BT549 breast cancer and MCF-10A normal cells.