[Inhibitory Effect of Ascorbic Acid on Myelodysplastic Syndrome Cells and Its Mechanism]

To investigate the inhibitory effect of ascorbic acid single or combination of decitabine on tumor cells of myelodysplastic syndrome (MDS) and explore its related mechanism.

The human MDS cell lines SKM-1 and MUTZ-1 were treated with different concentrations of ascorbic acid, and the cell proliferation activity was detected by the CCK-8 assay. The reactive oxygen species (ROS) level, labile iron pool (LIP), cell cycle, and apoptosis of SKM-1 and MUTZ-1 cells were detected by flow cytometry. The control group, ascorbic acid monotherapy group, decitabine monotherapy group, and combination group of ascorbic acid and decitabine were set up, the cell proliferation activity and apoptosis were detected in each group.

High-dose ascorbic acid could reduce the cell proliferation activity of SKM-1 (R=0.886, p=0.000) and MUTZ-1 (R=0.880, p=0.000). With the increase of ascorbic acid concentration, the ROS level in SKM-1 and MUTZ-1 cells increased (r=0.816, r=0.942), the proportion of cells stagnation in G₂ phase increased (r=0.970, p=0.000; r=0.962, p=0.000), the proportion of surviving cells decreased (r=-0.966, p=0.000; r=-0.952, p=0.000), and the apoptosis cells significantly increased (r=0.966, p=0.000; r=0.958, p=0.000). Nevertheless, the level of LIP showed no significant changes. After the combined application of ascorbic acid and decitabine, MDS tumor cells showed decreased proliferative activity and increased apoptosis compared with single-agent ascorbic acid and decitabine group.

High-dose ascorbic acid shows a cytotoxic effect on MDS tumor cells, inhibiting cell proliferation and increasing apoptosis. Ascorbic acid combined decitabine have a synergistic effect of anti-MDS tumor cells.