Application of arsenic trioxide in preparation of tumour immunomodulator

The invention belongs to the field of pharmaceuticals and relates to a tumour immunomodulator, specifically to a new application of arsenic trioxide (As2O3) in the preparation of a tumour immunomodulator. According to the invention, in vivo and in vitro interventions by arsenic trioxide with MDSCs in spleen of laboratory mice are conducted. The results show that arsenic trioxide inhibits proliferation of MDSCs, induces apoptosis and promotes mature phenotype distribution by lowering levels of p-STAT3, p-AKT, p-MEK and p-ERK in vitro and arsenic trioxide can reduce rate of MDSCs, promote its mature phenotype distribution and lower immunosuppressive activity of MDSCs in vivo. Results have effectively verified that arsenic trioxide has a killing effect on tumor-induced MDSCs and can be used in the preparation of a tumour immunomodulator, especially in the preparation of an immunomodulatory drug for myeloid-derived suppressor cells MDSCs.