These results demonstrate that in breast cancer cells, the overexpression of MIF promotes the secretion of VEGF-C, and the MAPK signaling pathway including p38 signaling pathway and ERK1/2 signaling pathway are activated by increasing the phosphorylation level of p38 and ERK1/2 (p44/42) and play a part in biological effects. The gene discussed is MAPK3; the disease is breast carcinoma.