Migration-inducing gene 7 promotes tumorigenesis and angiogenesis and independently predicts poor prognosis of epithelial ovarian cancer.

Epithelial ovarian carcinomas (EOC) cause more mortality than any other cancer of the female reproductive system. New therapeutic approaches to reduce EOC mortality have been largely unsuccessful due to the poor understanding of the mechanisms underlying EOC proliferation and metastasis. Progress in EOC treatment is further hampered by a lack of reliable prognostic biomarkers for early risk assessment. In this study, we identify that Migration-Inducting Gene 7 (MIG-7) is specifically induced in human EOC tissues but not normal ovaries or ovarian cyst. Ovarian MIG-7 expression strongly correlated with EOC progression. Elevated MIG-7 level at the time of primary cytoreductive surgery was a strong and independent predictor of poor survival of EOC patients. Cell and murine xenograft models showed that MIG-7 was required for EOC proliferation and invasion, and MIG-7 enhanced EOC-associated angiogenesis by promoting the expression of vascular endothelial growth factor. Inhibiting MIG-7 by RNA interference in grafted EOC cells retarded tumor growth, angiogenesis and improved host survival, and suppressing MIG-7 expression with a small molecule inhibitor D-39 identified from the medicinal plant Liriope muscari mitigated EOC growth and invasion and specifically abrogated the expression of vascular endothelial growth factor. Our data not only reveal a critical function of MIG-7 in EOC growth and metastasis and support MIG-7 as an independent prognostic biomarker for EOC, but also demonstrate that therapeutic targeting of MIG-7 is likely beneficial in the treatment of EOC.

Focal adhesion kinase: an alternative focus for anti-angiogenesis therapy in ovarian cancer.

This investigation describes the clinical significance of phosphorylated focal adhesion kinase (FAK) at the major activating tyrosine site (Y397) in epithelial ovarian cancer (EOC) cells and tumor-associated endothelial cells. FAK gene amplification as a mechanism for FAK overexpression and the effects of FAK tyrosine kinase inhibitor VS-6062 on tumor growth, metastasis, and angiogenesis were examined. FAK and phospho-FAK(Y397) were quantified in tumor (FAK-T; pFAK-T) and tumor-associated endothelial (FAK-endo; pFAK-endo) cell compartments of EOCs using immunostaining and qRT-PCR. Associations between expression levels and clinical variables were evaluated. Data from The Cancer Genome Atlas were used to correlate FAK gene copy number and expression levels in EOC specimens. The in vitro and in vivo effects of VS-6062 were assayed in preclinical models. FAK-T and pFAK-T overexpression was significantly associated with advanced stage disease and increased microvessel density (MVD). High MVD was observed in tumors with elevated endothelial cell FAK (59%) and pFAK (44%). Survival was adversely affected by FAK-T overexpression (3.03 vs 2.06 y, P = 0.004), pFAK-T (2.83 vs 1.78 y, P<0.001), and pFAK-endo (2.33 vs 2.17 y, P = 0.005). FAK gene copy number was increased in 34% of tumors and correlated with expression levels (P<0.001). VS-6062 significantly blocked EOC and endothelial cell migration as well as endothelial cell tube formation in vitro. VS-6062 reduced mean tumor weight by 56% (P = 0.005), tumor MVD by 40% (P = 0.0001), and extraovarian metastasis (P<0.01) in orthotopic EOC mouse models. FAK may be a unique therapeutic target in EOC given the dual anti-angiogenic and anti-metastatic potential of FAK inhibitors.

[Anti-angiogenic effects of zengmian YiIiu granule on ovarian carcinoma xenograft].

OBJECTIVE: To investigate the anti-angiogenic effects and mechanisms of Zengmian Yiliu Granule (ZMYLG) on ovarian carcinoma xenograft. METHODS: The SKOV3 ovarian carcinoma bearing mouse model was established. The tumor-bearing mice were randomly divided into the control group, the paclitaxel group, the high, medium, and low dose ZMYLG group, 8 in each group. The medication was lasted for ten days. The microvessel density (MVD) in the xenograft was calculated by the method of using cell membrane differentiation antigen 34 (CD34) antibody marking new vascular endothelial cells. The protein and mRNA expressions of vascular endothelial growth factor (VEGF) and its receptor fetal liver kinase-1 (FLK-1), hypoxia inducible factor-1alpha (HIF-1alpha) in the tumor were determined using immunohistochemical assay and RT-PCR. RESULTS: The MVD of ovarian carcinoma xenografts in the paclitaxel group, the high, medium, and low dose ZMYLG group obviously decreased, showing statistical difference when compared with the control group (P < 0.01, P < 0.05). Each ZMYLG dose group could down-regulate the protein and mRNA expressions of VEGF, FLK-1, and HIF-1alpha (P < 0.01, P < 0.05). CONCLUSIONS: ZMYLG could inhibit neogenesis of tumor vessels. Its mechanisms might be associated with down-regulating the expression of HIF-1alpha, modifying the hypoxic state, inhibiting the expressions of VEGF and FLK-1, and exerting its anti-angiogenic effects.