Effects of a single-dose administration of Bowman-Birk inhibitor concentrate on anti-proliferation and inhabitation of metastasis in M5076 ovarian sarcoma-bearing mice

Abstract

The present study was designed to investigate the effects of Bowman-Birk inhibitor concentrate (BBIC) on anti-proliferation, up-regulation of Connexin 43 (Cx43) expression and inhabitation of hepatic metastasis in mice with M5076 ovarian sarcoma. M5076 ovarian sarcomas (1x106 cells/animal) were subcutaneously transplanted into the back of BDF1 mice. The 'pre-treated' (n=10) and 'post-treated' (n=10) groups were fed a standard diet (CE-2) compounded with 0.5% BBI from 3 weeks before and from the day of tumor inoculation, respectively, until 4 weeks after tumor inoculation. The 'control group' (n=10) was fed CE-2 alone. Relative tumor weights in the pre- (0.013±0.010) and post- (0.012±0.013) treated groups were significantly reduced by 30.0 and 32.5%, respectively, as compared to the control group (0.040±0.022, p<0.01). The relative densities of Cx43 mRNA and Cx43 protein were significantly higher in the BBIC-treated groups than in the control group. The median numbers of macroscopic spontaneous metastases were significantly lower in the pre- (1.0±2.3) and post- (1.9±3.6) treated groups than in the control group (71.4±97.3). These results suggest that BBIC reduces proliferation as a result of increased expression of Cx43 genes in mice with M5076 ovarian sarcoma. In addition, BBIC inhibits hepatic metastasis in M5076-bearing mice.