OBJECTIVETo in vitro study the inhibition effect and possible mechanism of As2S3 nanoparticles (As2S3 nano) on human MDS cell line MUTZ-1 and to compare with that of traditional As2S3.

METHODMUTZ-1 cells were treated with As2S3 nano and traditional regular-sized particles (TRSP) at different concentrations. The cell growth inhibition rate was determined by MTT assay, cell apoptosis by morphology and flow cytometry (FCM), cell cycle by FCM and the activity of caspase-3 by chemiluminescence assay.

RESULTSTreatment of As2S3 nano and TRSP at concentrations of 2, 4, 8 and 16 micromol/L for 48 h could lead to a significant dose-dependent decrease of MUTZ-1 cells and induce apoptosis. The percentages of inhibition were 48.9%, 75.9%, 89.4% and 96.5% in As2S3 nano vs 14.5%, 25.4%, 34.7% and 51.5% in TRSP and apoptosis rates were (12.9 +/- 1.9)%, (19.2 +/- 2.2)%, (30.1 +/- 2.5)% and (45.9 +/- 2.3)% in As2S3 nano vs (5.3 +/- 1.8%)%, (11.1 +/- 2.6)%, (19.3 +/- 2.3)% and (25.5 +/- 2.5)% in TRSP respectively. There was statistically significant difference in these two groups (P < 0.01). The proportion of cell in G2/M phase and the activity of caspase-3 of MUTZ-1 cells treated with A2S32 nano were significantly higher than those treated with control group and As2S3 TRSP groups (P < 0.01).

CONCLUSIONSAs2S3 nanoparticles and TRSP can inhibit the proliferation of MUTZ-1 cells and induce apoptosis, which maybe through activating caspase-3 pathways and increasing the proportion of G2/M phase. As2S3 nanoparticles can produce a much better antitumor effect than As2S3 TRSP do.