STAT3 and neoplasm: Therefore, Stat3 is important for tumor angiogenesis and metastasis.12, 18, 44 Our in vivo studies indicated that the treatment of mice with nifuroxazide caused a significant reduction in the number of MDSCs in the spleen, blood and tumors compared with that of the vehicle group, which was also accompanied by an increased infiltration of CD8+ T cells in the tumors.