Clinical significance of macrophage migration inhibitory factor in invasion of ovarian cancer

Abstract

Macrophage migration inhibitory factor (MIF) is closely related to tumorigenesis. This study was to investigate the effects of MIF gene on migration, invasion and proliferation of ovarian cancer cells and to evaluate the significance of MIF protein expression in ovarian cancer tissues. Small interfering RNA was used to transiently knock down the expression of MIF gene in HO-8,910 and OVCAR-3 cells. The effect of RNAi was assessed by RT-PCR and western blot. The migration, invasion and proliferation of ovarian cancer cells were determined by transwell chamber assay, invasion assay and MTT assay, respectively. Immunohistochemistry was utilized to examine the expression status of MIF in ovarian cancer tissues. MIF RNAi significantly inhibited MIF expression in HO-8910 and OVCAR-3 cells and decreased cell proliferation of the two cells (P<0.05). The numbers of migrated and invaded HO-8910 cells were significantly less in the MIF-si1 and MIF-si2 groups than in the NC group, respectively [migration: (48.0+/-7.3) and (38.0+/-3.6) vs. (78.0+/-8.5), P<0.05; invasion: (35.0+/-5.0) and (30.0+/-5.6) vs. (65.0+/-4.6), P<0.05]. The numbers of migrated and invaded OVCAR-3 cells were significantly less in the MIF siRNA groups than in the NC group, respectively [migration: (40.0+/-4.5) and (42.0+/-3.0) vs. (65+/-2.1), P<0.05; invasion: (25.0+/-3.0) and (27.0+/-3.4) vs. (48.0+/-2.4), P<0.05]. Positive expression of MIF protein was detected in 53.5% of ovarian carcinoma tissues and was positively correlated to clinical stages of patients (P<0.01). MIF might play an important role in the pathogenesis and progression of ovarian cancer. Thus, MIF might be used as a potential therapeutic target in ovarian cancer.