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Multifaceted functions of the so-called "oncogene" Wip1 have been reported in a previous study, while its actual role remains to be explored in serous ovarian cancer (SOC). In this study, by performing bioinformatic analysis with a public database and immunohistochemical staining of Wip1 in tumour tissue from SOC, we concluded that decreased expression of Wip1 was associated with a higher rate of tumour metastasis and platinum-based therapy resistance and increased ascites volume, which led to poorer prognosis in SOC patients. We also found that overexpression of Wip1 in SKOV3 cells decreased the levels of several cytokines, including VEGF, by secretome profiling analysis, and Wip1 overexpression suppressed angiogenesis both in vitro and in vivo. Mechanistic studies indicated that overexpression of Wip1 decreased the expression of VEGF at both the protein and mRNA levels and that the inhibitory effect was mediated by dephosphorylation of STAT3 at Ser727. Our study uncovered the role of Wip1 in SOC and provides a novel therapeutic strategy for suppressing angiogenesis., (© 2022. The Author(s).)

Purpose: The heterogeneous phenotype of epithelial ovarian cancer (EOC) explains the unpredictable behaviour in terms of response to therapy, time to progression and survival. In this context, CD146, a cell adhesion molecule, has been focused on as a marker of poor prognosis in various solid cancers, being also capable to modulate the activity of endothelial cells. Therefore, we proposed to investigate its role in serous ovarian carcinoma., Methods: The study included 101 patients diagnosed with EOC and treated within "Ion Chiricuta" Oncology Institute by optimal surgical debulking followed by platinum-based chemotherapy. Clinico-pathological characteristics were collected from patient files. CD146 expression was assessed by immunohistochemistry in serous ovarian carcinoma primary tumours, taking into account both staining intensity and the percentage of positive tumor cells. Expression of CD146 in endothelial cells of tumour microvessels was also evaluated. CD34 immunostaining was used for intratumoral microvessel density estimation., Results: CD146 positivity in tumor cells was objectified in 49.5% of samples and 37.1% presented a high CD146 endothelial expression. Our analysis showed that CD146 was as reliable as CD34 for microvascular density estimation. The distribution of cases according to CD146 tumor expression was similar regardless of age, initial serum CA125 level, FIGO stage, presence/absence of malignant ascites. Multivariate analysis confirmed that expression of CD146 in tumor cells was a negative prognostic factor for overall survival, significantly asociated with a higher risk of chemotherapy resistance., Conclusions: Although CD146 immunoreactivity in tumor cells did not correlate with the routinely used clinico-pathological parameters, expression of CD146 in tumor cells was an independent pronostic factor for survival in serous ovarian carcinomas. Moreover, CD146 might be regarded as a novel biomarker of tumor neovasculature.

Objective: The impact of angiogenesis on long-term survival of high-grade serous ovarian cancer (HGSOC) patients remains unclear. This study investigated whether angiogenic markers correlated with 5-year progression-free survival (PFS) in a large cohort of matched advanced HGSOC tissue samples., Methods: Tumor samples from 124 primary HGSOC patients were retrospectively collected within the Tumor Bank Ovarian Cancer ( http://www.toc-network.de ). All patients were in advanced stages (FIGO stage III-IV). No patient had received anti-angiogenesis therapy. The cohort contains 62 long-term survivors and 62 controls matched by age and post-surgical tumor residuals. Long-term survivors were defined as patients with no relapse within 5 years after the end of first-line chemotherapy. Controls were patients who suffered from first relapse within 6-36 months after primary treatment. Samples were assessed for immunohistochemical expression of vascular endothelial growth factor (VEGF) A and VEGF receptor 2 (VEGFR2). Expression profiles of VEGFA and VEGFR2 were compared between the two groups., Results: Significant correlation between VEGFA and VEGFR2 expression was observed (p < 0.0001, Spearman coefficient 0.347). A high expression of VEGFR2 (VEGFR2 high ) was found more frequently in long-term survivors (77.4%, 48/62) than in controls (51.6%, 30/62, p = 0.001), independent of FIGO stage and VEGFA expression in multivariate analysis (p = 0.005). Also, VEGFR2 high was found the most frequently in women with PFS ≥ 10 years (p = 0.001) among all 124 patients. However, no significant association was detected between VEGFA expression and 5-year PFS (p = 0.075)., Conclusions: VEGFR2 overexpression significantly correlated with long-term PFS in HGSOC patients, independent of age, FIGO stage, tumor residual and VEGFA expression.

High-grade serous ovarian carcinoma (HGSOC) is one of the most lethal gynecologic malignancies. Currently, anti-angiogenesis therapy is the most promising strategy for the successful treatment of HGSOC. In this study, we found Neferine could inhibit the angiogenesis of ovarian cancer cells both in vitro and in vivo. Further analysis revealed that its suppressive effect on human umbilical vein endothelial cell (HUVEC) proliferation correlated with promoting cell cycle arrest and autophagy. The cell cycle genes were dose-dependently reduced and the level of LC3II/LC3I (microtubule associated protein 1 light chain 3) was increased. Using a specific marker for macrophages (CD206 and Mrc1), we indicated that Neferine could inhibit M2-macrophage in vivo. Finally, CD206 was stained in 150 HGSOC samples and its high expression predicted inferior overall survival. Our current study is the first to demonstrate the anti-angiogenesis mechanism of Neferine by inducing autophagy via mTOR/p70S6K pathway inhibition and suppressing M2-macrophage polarization. Our findings suggest that Neferine is an attractive reagent with great potential in HGSOC therapy, especially in standard-therapy resistant cases., (Copyright © 2018. Published by Elsevier B.V.)

Objective: We recently established that high STAT1 expression and associated T helper type I tumour immune microenvironment (TME) are prognostic and chemotherapy response predictive biomarkers in high-grade serous ovarian cancer (HGSC). STAT1 induced chemokine CXCL10 is key to the recruitment of lymphocytes in the TME and is significantly highly expressed in the tumours from patients with longer survival. In the current study we therefore aimed to elucidate the role CXCL10 in disease progression and tumour immune transcriptomic alterations using the ID8 syngeneic murine model of HGSC., Methods: ID8 ovarian cancer cells were engineered for stable knockdown (KD) and overexpression (OX) of CXCL10. The OX and KD cell line derivatives, along with their respective vector controls, were implanted in immunocompetent C57BL/6 mice via intra-peritoneal injections. At end point, immune transcriptomic profiling of tumour tissues and multiplex cytokine profiling of ascites, was performed. Effect of CXCL10 expression on the tumour vasculature and tumour cell proliferation was evaluated by CD31 and Ki67 immunostaining, respectively., Results: Increased CXCL10 expression led to decreased tumour burden and malignant ascites accumulation in the ID8 syngeneic murine model of HGSC. The ascites levels of IL-6 and VEGF were significantly reduced in OX mice compared to the vector controls. The OX tumours also showed reduced vasculature (CD31) and proliferative index (Ki67) compared to the control tumours. Significantly higher expression of genes associated with antigen processing, apoptosis and T cell function was observed in OX tumours compared to the controls. Reduced CXCL10 expression in tumours from KD mice led to increased ascites accumulation and disease progression compared to the controls., Conclusion: CXCL10 is a positive determinant of anti-tumour immune responses in HGSC TME and disease progression. These findings are foundational for future translational studies aimed at improving treatment response and survival in HGSC patients, via exploiting the TME., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Angiogenesis is a hallmark of ovarian cancer (OC); the ingrowth of blood vessels promotes rapid cell growth and the associated metastasis. Melatonin is a well-characterized indoleamine that possesses important anti-angiogenic properties in a set of aggressive solid tumors. Herein, we evaluated the role of melatonin therapy on the angiogenic signaling pathway in OC of an ethanol-preferring rat model that mimics the same pathophysiological conditions occurring in women. OC was chemically induced with a single injection of 7,12-dimethylbenz(a)anthracene (DMBA) under the ovarian bursa. After the rats developed serous papillary OC, half of the animals received intraperitoneal injections of melatonin (200 µg/100 g body weight/day) for 60 days. Melatonin-treated animals showed a significant reduction in OC size and microvessel density. Serum levels of melatonin were higher following therapy, and the expression of its receptor MT1 was significantly increased in OC-bearing rats, regardless of ethanol intake. TGFβ1, a transforming growth factor-beta1, was reduced only after melatonin treatment. Importantly, vascular endothelial growth factor (VEGF) was severely reduced after melatonin therapy in animals given or not given ethanol. Conversely, the levels of VEGF receptor 1 (VEGFR1) was diminished after ethanol consumption, regardless of melatonin therapy, and VEGFR2 was only reduced following melatonin. Hypoxia-inducible factor (HIF)-1α was augmented with ethanol consumption, and, notably, melatonin significantly reduced their levels. Collectively, our results suggest that melatonin attenuates angiogenesis in OC in an animal model of ethanol consumption; this provides a possible complementary therapeutic opportunity for concurrent OC chemotherapy.

Fatty acid binding protein 4 (FABP4) is a fatty acid chaperone, which is induced during adipocyte differentiation. Previously we have shown that FABP4 in endothelial cells is induced by the NOTCH1 signalling pathway, the latter of which is involved in mechanisms of resistance to antiangiogenic tumour therapy. Here, we investigated the role of FABP4 in endothelial fatty acid metabolism and tumour angiogenesis. We analysed the effect of transient FABP4 knockdown in human umbilical vein endothelial cells on fatty acid metabolism, viability and angiogenesis. Through therapeutic delivery of siRNA targeting mouse FABP4, we investigated the effect of endothelial FABP4 knockdown on tumour growth and blood vessel formation. In vitro, siRNA-mediated FABP4 knockdown in endothelial cells led to a marked increase of endothelial fatty acid oxidation, an increase of reactive oxygen species and decreased angiogenesis. In vivo, we found that increased NOTCH1 signalling in tumour xenografts led to increased expression of endothelial FABP4 that decreased when NOTCH1 and VEGFA inhibitors were used in combination. Angiogenesis, growth and metastasis in ovarian tumour xenografts were markedly inhibited by therapeutic siRNA delivery targeting mouse endothelial FABP4. Therapeutic targeting of endothelial FABP4 by siRNA in vivo has antiangiogenic and antitumour effects with minimal toxicity and should be investigated further.

Only recently low-grade serous carcinoma (LGSOC) of the ovary has been recognized as a disease entity distinct from the more common high-grade serous carcinoma (HGSOC), with significant differences in pathogenesis and clinical and pathologic features. The present study aimed at evaluating whether the different natural histories and patterns of response to therapy demonstrated for LGSOC and HGSOC, along with a diverse genomic landscape, may also reside in the supporting tumor stroma, specifically in the state of differentiation and activation of tumor associated macrophages (TAMs). TAMs play complex roles in tumorigenesis since they are believed to possess both tumor rejecting (M1 macrophages) and tumor promoting (M2 macrophages) activities. Here we showed that, when compared to HGSOC (n = 55), LGSOC patients (n = 25) exhibited lower density of tumor-infiltrating CD68+ macrophage, along with an attenuated M2-skewed (CD163+) phenotype. Accordingly, assessment of intratumoral vascularization and of matrix metalloproteinase 9 expression (a key protein involved in tumor invasion and metastasis) revealed lower expression in LGSOC compared to HGSOC patients, in line with emerging evidence supporting a role for TAMs in all aspects of tumor initiation, growth, and development. In conclusion, results from the present study demonstrate that microenvironmental factors contribute greatly to determine clinical and pathological features that differentiate low and high grade serous ovarian carcinomas. This understanding may increase possibilities and opportunities to improve disease control and design new therapeutic strategies.

Vasculogenic minicry (VM), an alternative blood supply modality except to endothelial cells-mediated vascular network, is a potential therapeutic target for ovarian cancer due to VM correlated with poor prognosis in ovarian cancer patients. Accelerated extracellular matrix (ECM) degradation is prerequisite for VM formation induced by epithelial-mesenchymal transition (EMT). Previous reports demonstrate uPA has ability to degrade ECM thereby promoting tumor angiogenesis. Also, exogenous cRGD sequence enables to modulate uPA expression, attenuate EMT and suppress endothelial-lined channels. Till now, the correlation of uPA and VM formation and the effect of exogenous cRGD on VM formation remain unknown. Herein, we validate uPA expression is positively correlated with VM formation in ovarian cancer tissues (90 cases) and ovarian cancer cells (SKOV-3, OVCAR-3 and A2780 cells). In particular, silencing uPA experiments show that down-regulated uPA causes notable decrease for the complete channels formed by SKOV-3 and OVCAR-3 cells. Mechanism study discloses uPA promotes VM formation by regulating AKT/mTOR/MMP-2/Laminin5γ2 signal pathway. The result demonstrates uPA may serve as therapeutic target of VM for ovarian cancer. Also, it is found exogenous cRGD enables to inhibit VM formation in ovarian cancer via not only down-regulating uPA expression but also reducing EMT. Exogenous cRGD may be a promising angiogenic inhibitor for ovarian cancer therapy due to its inhibiting effect on VM formation as well as endothelial cells-mediated vascular network., Competing Interests: The authors report no conflicts of interest in this work.

Fibroblast growth factor 18 (FGF18) has been suggested to play important roles in promoting progression of ovarian high-grade serous carcinoma. Our aim was to investigate FGF18 expression in the whole spectrum of serous and mucinous ovarian tumors, highlighting differences in expression within the adenoma-carcinoma sequence and differences between type I and type II tumors. We also aimed to test the prognostic significance of this expression and its relation to microvessel density (MVD). We evaluated the immunohistochemical expression of FGF18 and CD31 in 103 ovarian tumors and statistically analyzed their association with clinicopathological variables and patients' outcome. FGF18 score increased significantly within the adenoma-carcinoma sequence for serous and mucinous tumors. MVD increased significantly only among serous tumors. FGF18 and MVD correlated significantly (overall and among serous tumors only) and were significantly higher in type II than type I tumors. Cox regression models were built. Independent predictors could not be determined due to multicollinearity between the predictors. However, the combination of International Federation of Gynecology and Obstetrics (FIGO) stage, ovarian carcinoma type, and/or FGF18 score achieved the highest predictability of poor prognosis. FGF18 could play a role within the adenoma-carcinoma sequence in type I tumors and might modulate angiogenesis among serous tumors. Our findings further augment the differences between type I and type II tumors. The combination of FIGO stage, ovarian carcinoma type, and/or FGF18 score could predict poor prognosis among ovarian carcinoma patients. Our work identifies FGF18 in ovarian neoplasia as a promising field of research, although evaluation of the performance of the developed models is still needed.

Objectives: To identify angiogenic biomarkers associated with tumor angiogenesis and clinical outcome in high-grade serous ovarian cancer (HGSC)., Methods: 51 HGSC samples were analyzed using Affymetrix HG-U133A microarray. Microvessel density (MVD) counts were determined using CD31 and CD105. Associations between mRNA expression levels and overall survival were assessed using rank score statistic. Effect size was estimated as a hazard ratio (HR) under a proportional hazard model. The Storey q-value method was used to account for multiple testing within the false-discovery rate (FDR) framework. Publicly available databases including TCGA and GSE were used for external confirmation., Results: Thirty-one angiogenic-related genes were significantly associated with survival (q≤0.05). Of these 31 genes, 4 were also associated with outcome in the TCGA data: AKT1 (q=0.02; TCGA p=0.01, HR=0.8), CD44 (q=0.003; TCGA p=0.05, HR=0.9), EPHB2 (q=0.01; TCGA p=0.05, HR=1.2), and ERBB2 (q=0.02; TCGA p=0.05, HR=1.2). While 5 were associated with outcome in the GSE database: FLT1 (q=0.03; GSE26712 p=0.01, HR=3.1); PF4 (q=0.02; GSE26712 p=0.01, HR=3.0); NRP1 (q=0.02; GSE26712 p<0.04, HR>1.4); COL4A3 (q=0.04; GSE26712 p=0.03, HR=1.3); and ANGPTL3 (q=0.02; GSE14764 p=0.02, HR=1.5). High AKT1 and CD44 were associated with longer survival. In contrast, high expression of EPHB2, ERBB2, FLT1; PF4, NRP1, COL4A3, and ANGPTL3 were associated with shorter survival. CD105-MVD and CD31-MVD were not significantly associated with angiogenic gene expression., Conclusions: Thirty-one angiogenic-related genes were associated with survival in advanced HGSC and nine of these genes were confirmed in independent publicly available databases., (Copyright © 2015 Elsevier Inc. All rights reserved.)

MicroRNAs (miRNAs) have been shown to play an important role in diverse biological processes and cancer progression. The objective of the present study was to investigate the role of miR-497 in ovarian cancer angiogenesis. We found that miR-497 expression was downregulated in human ovarian cancer tissues, and the low miR-497 expression was significantly associated with increased angiogenesis. Functionally, exogenous expression of miR-497 suppressed the ability of ovarian cancer cells to promote capillary tube formation of endothelial cells. We further disclosed that miR-497 exerted its function of anti-angiogenesis by suppressing VEGFA expression in ovarian cancer cells and, in turn, impairing the VEGFR2-mediated PI3K/AKT and MAPK/ERK pathways. Our findings suggest that downregulation of miR-497 may contribute to angiogenesis in ovarian cancer. miR-497 may be a promising candidate target for prevention and treatment of ovarian cancer.

Background: When T cells infiltrate the tumor environment they encounter a myriad of metabolic stressors including hypoxia. Overcoming the limitations imposed by an inadequate tumor vasculature that contributes to these stressors may be a crucial step to immune cells mounting an effective anti-tumor response. We sought to determine whether the functional capacity of tumor infiltrating lymphocytes (TIL) could be influenced by the tumor vasculature and correlated this with survival in patients with ovarian cancer., Methodology and Principal Findings: In 196 high-grade serous ovarian tumors, we confirmed that the tumor vascularity as measured by the marker CD31 was associated with improved patient disease-specific survival. We also found that tumors positive for markers of TIL (CD8, CD4 and forkhead box P3 (FoxP3)) and T cell function (granzyme B and T-cell restricted intracellular antigen-1 (TIA-1)) correlated significantly with elevated vascularity. In vitro, hypoxic CD8 T cells showed reduced cytolytic activity, secreted less effector cytokines and upregulated autophagy. Survival analysis revealed that patients had a significant improvement in disease-specific survival when FoxP3 expressing cells were present in CD31-high tumors compared to patients with FoxP3 expressing cells in CD31-low tumors [HR: 2.314 (95% CI 1.049-5.106); p = 0.0377]. Patients with high vascular endothelial growth factor (VEGF) expressing tumors containing granzyme B positive cells had improved survival compared to patients with granzyme B positive cells in VEGF-low tumors [HR: 2.522 (95% CI 1.097-5.799); p = 0.0294]., Significance: Overall, this data provides a rationale for developing strategies aimed at improving the adaptability and function of TIL to hypoxic tumor conditions.

Epithelial ovarian cancer is the most lethal gynecologic malignancy; it is highly aggressive and causes almost 125,000 deaths yearly. Despite advances in detection and cytotoxic therapies, a low percentage of patients with advanced stage disease survive 5 y after the initial diagnosis. The high mortality of this disease is mainly caused by resistance to the available therapies. Here, we profiled microRNA (miR) expression in serous epithelial ovarian carcinomas to assess the possibility of a miR signature associated with chemoresistance. We analyzed tumor samples from 198 patients (86 patients as a training set and 112 patients as a validation set) for human miRs. A signature of 23 miRs associated with chemoresistance was generated by array analysis in the training set. Quantitative RT-PCR in the validation set confirmed that three miRs (miR-484, -642, and -217) were able to predict chemoresistance of these tumors. Additional analysis of miR-484 revealed that the sensitive phenotype is caused by a modulation of tumor vasculature through the regulation of the VEGFB and VEGFR2 pathways. We present compelling evidence that three miRs can classify the response to chemotherapy of ovarian cancer patients in a large multicenter cohort and that one of these three miRs is involved in the control of tumor angiogenesis, indicating an option in the treatment of these patients. Our results suggest, in fact, that blockage of VEGF through the use of an anti-VEGFA antibody may not be sufficient to improve survival in ovarian cancer patients unless VEGFB signaling is also blocked.

Vasohibin-1 (VASH1) is a VEGF-inducible endothelium-derived angiogenesis inhibitor and VASH2 is its homolog. Our previous analysis revealed that VASH1 is expressed in endothelial cells to terminate angiogenesis, whereas VASH2 is expressed in infiltrating mononuclear cells mobilized from bone marrow to promote angiogenesis in a mouse model of hypoxia-induced subcutaneous angiogenesis. To test the possible involvement of VASH2 in the tumor, we examined human ovarian cancer cells for the presence of VASH2. Immunohistochemical analysis revealed that VASH2 protein was preferentially detected in cancer cells of serous ovarian adenocarcinoma. We then used SKOV-3 and DISS, two representative human serous adenocarcinoma cell lines, and examined the role of VASH2 in the tumor. The knockdown of VASH2 showed little effect on the proliferation of cancer cells in vitro but notably inhibited tumor growth, peritoneal dissemination, and tumor angiogenesis in a murine xenograft model. Next, we stably transfected the human VASH2 gene into two types of murine tumor cells, EL-4 and MLTC-1, in which endogenous VASH2 was absent. When either EL-4 or MLTC-1 cells were inoculated into VASH2 (-/-) mice, the VASH2 transfectants formed bigger tumors when compared with the controls, and the tumor microvessel density was significantly increased. VASH2 stimulated the migration of endothelial cells, and its increased expression in cancer cells is related to the decrease of mir-200b. These results indicate that VASH2 expressed in serous ovarian carcinoma cells promoted tumor growth and peritoneal dissemination by promoting angiogenesis.

Currently, great interest is focused on the anti-neoplastic effects of CXC chemokine ligand 10 (IP-10/CXCL10). IP-10 has shown significant antitumor and anti-metastatic properties via immunological, antiangiogenic and anti-neoplastic mechanisms. However, very few studies on the antitumor activity of IP-10 in human ovarian cancer have been reported. The use of polymeric nanoparticles to deliver functional genes intraperitoneally holds much promise as an effective therapy for ovarian cancer. In our study, a recombinant plasmid expressing IP-10 (pVITRO-IP-10) was constructed, and biodegradable cationic heparin-polyethyleneimine (HPEI) nanogels were prepared to deliver pVITRO-IP-10 into SKOV3 human ovarian cancer cells. Transfection efficiency was detected by expression profiling of green fluorescent protein. The expression of IP-10 was determined using RT-PCR and western blot analysis. In vitro, cell proliferation was evaluated by MTT assay. Apoptosis was examined by Hoechst33258/PI staining and flow cytometry assays. The effect on the inhibition of angiogenesis was evaluated by tube formation assay using human umbilical vein endothelial cells (HUVECs). Moreover, a SKOV3 intraperitoneal ovarian carcinomatosis model was established to investigate the antitumor activity of HPEI+pVITRO-IP-10 complexes in nude mice. Tumor weights were evaluated during the treatment course. Cell proliferation and apoptosis were evaluated by Ki-67 immunochemical staining and TUNEL assay, and the antiangiogenic effect of pVITRO-IP-10 was assessed by CD31 immunochemical staining and alginate-encapsulated tumor cell assay. pVITRO-IP-10 was efficiently transfected into SKOV3 cells by HPEI nanogels. Intraperitoneal administration of HPEI+pVITRO-IP-10 complexes led to effective growth inhibition of ovarian cancer, in which tumor weight decreased by ~69.92% in the treatment group compared with that in the empty vector control group. Meanwhile, decreased cell proliferation, increased tumor cell apoptosis and reduction in angiogenesis were observed in the HPEI+pVITRO-IP-10 group compared with those in the control groups. These results indicated that HPEI nanogel delivery of pVITRO-IP-10 may be of value in the treatment against human ovarian cancer.

The aim of the study was to assess the microvessel density (MVD) and vascular endothelial growth factor (VEGF) expression in ovarian serous carcinoma and to examine their relation with apoptosis.Paraffin-embedded specimens of 41 cases of ovarian serous carcinomas were evaluated by immunohistochemistry for VEGF, p53, and bcl-2 expression. MVD was assessed with CD31 staining. We investigated the association of tumor angiogenesis (MVD and VEGF) with clinicopathologic factors, p53 overexpression, and bcl-2 expression.There was a significant correlation between high MVD and suboptimal debulking and advanced stage disease. A significant negative correlation was expressed between bcl-2 and VEGF expression. In univariate analysis, only stage had a significant impact on disease-free survival.The results of this study suggest that higher degree of angiogenesis is associated with suboptimal debulking and advanced-stage disease. Expression of VEGF had negative association with VEGF expression.

Objective: The purpose of this study is to examine the role of versican (VCAN) in advanced stage serous ovarian cancer by investigating its expression, its function, and its correlation with clinical outcomes., Methods: Microarray analysis was performed on RNA isolated from tumor and stromal components of advanced stage serous ovarian cancer and normal ovarian epithelial tissue to identify genes up-regulated in ovarian tumor stroma. Validation studies using immunohistochemistry and quantitative real-time PCR (Q-RT-PCR) was performed on one of the up-regulated genes, VCAN. Immunolocalization of VCAN (n=111) and CD31 (n=56) was done on serous ovarian tumors. CD31 staining was performed to examine microvessel density (MVD). Q-RT-PCR was performed on 65 samples to evaluate the differential expression of VCAN isoforms. Cell proliferation and invasion assays were performed to examine how V1-treated ovarian cancer cell lines and an endothelial cell line would differ from controls. Univariate survival analyses were done with VCAN expression. Correlation analysis was done with CD31, platinum resistance, and clinical data., Results: Validation studies using Q-RT-PCR and immunohistochemistry showed significantly higher VCAN V1 isoform expression in ovarian cancer stroma compared with normal ovarian stroma and ovarian cancer cells. Correlation studies showed stromal VCAN expression was associated with poorer overall and progression-free survival, platinum resistance, and increased MVD. VCAN-treated ovarian cancer and endothelial cells showed increased invasion potential., Conclusions: VCAN overexpression is associated with increased MVD and invasion potential, which may lead to poorer overall and progression-free survival and platinum resistance., (Copyright © 2010 Elsevier Inc. All rights reserved.)

The Risk of Malignancy Index (RMI) is used for the prediction of ovarian malignancy. It includes menopausal status, carbohydrate antigen 125 serum levels, and ultrasound criteria. Three-dimensional power Doppler (3-DPD) is a reproducible investigation for assessment of tumor vascularity, classifying vascularity to avascular, parallel, and chaotic patterns. In this study; 3-DPD was added to RMI for prediction of malignancy in 400 cases of ovarian masses. Sensitivity of RMI for prediction of malignancy was 88%, with a cutoff value of 202.5 at 95% confidence interval. Sensitivity of 3-DPD for prediction of malignancy was 75%, adding 3-DPD to RMI increased its sensitivity to 99%. Considering the pilot nature of the study, further studies are needed to corroborate such findings.

Aims: Clinical stage at the time of diagnosis and achievement of complete macroscopic resection during initial surgery are key factors determining the outcome of ovarian cancer. However, prediction of outcome lacks accuracy and more reliable prognostic factors are required. Therefore, an analysis and evaluation of key angiogenic factors was carried out to determine their diagnostic and prognostic value in serous ovarian cancer., Methods: Expression levels of vascular endothelial growth factor (VEGF)-A, hypoxia-inducible factor (HIF)1-alpha and inducible nitric oxide synthase (i-NOS) were analysed by immunohistochemistry in a homogenous group of 112 patients with serous adenocarcinoma of the ovary. Vascular density as an indicator of angiogenesis was assessed using the Chalkley eyepiece method after staining for CD34. The correlation of these data with survival and established prognostic factors such as histological grade, Federation of Gynecology and Obstetrics (FIGO) stage, and residual tumour after surgery, was evaluated. Survival analyses, multivariate analyses and correlation tests were performed., Results: In the patient group with macroscopic complete tumour resection (R0) there was a significant correlation between VEGF-A and i-NOS expression. Kaplan-Meier analysis further revealed improved progression-free survival for R0 patients with VEGF-A-positive and i-NOS-negative tumours. The predictive relevance of VEGF-A regarding progression-free survival was sustained in multivariate analysis using FIGO stage, grading and resection status as fixed variables., Conclusion: VEGF-A and i-NOS are prognostic markers for clinical outcome in serous ovarian cancer patients with macroscopic complete tumour resection (R0). Hence, pre-therapeutic assessment of VEGF-A as predictive factor for an antiangiogenic therapy might be of clinical value.

Objective: To clarify the association of EGFR expression with angiogenesis and chemoresistance in ovarian cancer., Methods: Immunohistochemical PV-6000 staining was used to detect the expression of EGFR, LRP protein and MVD in 102 ovarian tumor specimens., Results: EGFR, LRP positive rates and MVD in borderline and malignant ovarian specimens were significantly higher than those in the normal and benign ones (P < 0.01). EGFR positive expression rate in stage III-IV carcinoma tissues, poor differentiation and with ascites was higher than that in stage I-II carcinomas of well differentiation and without ascites (P < 0.05). MVD was related to histological grade, residual tumor and ascites, LRP positive expression had no correlation with the clinicopathologic parameters (P > 0.05). The effective rate of chemotherapy in patients with EGFR and LRP-positive expression were 57.1% and 53.7%, respectively, significantly lower than that in cases with EGFR and LRP-negative expression (85.0% and 90.9%, P < 0.05). In the 64 cases with complete data, the three-year survival rate was 53.0%. The survival time was shorter in the cases with EGFR and LRP-positive expression, poor differentiation, ascites and chemoresistance (P < 0.01), and only LRP-positive expression and chemotherapeutic effect were independently related to survival time (P < 0.05). There was a correlation between EGFR and MVD (r = 0.548, P < 0.01), EGFR and LRP positive expression (P = 0.020)., Conclusion: The expression of EGFR in ovarian cancer is related to angiogenesis and chemoresistance. EGFR and LRP-positive expression are related to chemoresistance, and detection of the two proteins may be helpful in guiding chemotherapy choice for ovarian cancer. LRP-positive expression and chemotherapeutic effect may be independent prognostic factors.

Lymph node involvement is seen in approximately one quarter of women with surgically staged ovarian serous tumors of low malignant potential (serous borderline tumors), and this finding apparently does not adversely impact their overall survival. To help illuminate some of the pathomechanisms underlying this novel phenomenon, in which a largely noninvasive epithelial neoplasm is able to exit its primary site and be transported to lymph nodes with such a substantial frequency, we investigated whether significant differences in lymphatic vessel density exist between ovarian serous borderline tumors that show lymph node involvement and those that do not. The lymphatic vessel density of 13 conventional ovarian serous borderline tumors (i.e. tumors without stromal microinvasion, micropapillary/cribriform areas, or invasive implants) with at least 1 positive lymph node (study group) was compared with the lymphatic vessel density of an age- and disease extent-matched control group of 13 similarly selected lymph node-negative ovarian serous borderline tumors. Lymphatic vessel density was determined by counting the total number of vascular spaces immunohistochemically stained by the lymphatic endothelium marker D2-40 in 5 consecutive microscopic fields (x20 objective, field area of 1 microscopic field, 0.95 mm) in the most vessel-dense areas and calculating the average value per microscopic field. The peritumoral lymphatic vessel density was significantly higher than the intratumoral lymphatic vessel density in both groups. However, no statistically significant differences were found between the study and control groups regarding intratumoral lymphatic vessel density (8.0 vs. 7.61; P=0.77), peritumoral lymphatic vessel density (20.33 vs. 21.0; P=0.79), or combined, that is, peritumoral plus intratumoral lymphatic vessel density (27.81 vs. 28.62; P=0.83). Our findings, in conjunction with others in the medical literature, do not support a role for tumor lymphatics in nodal metastasis in this neoplasm. We discuss the possibility that nodal deposits may represent metastatic disease from secondary tumor implants.

Objective: To evaluate the correlations of microvessel density (MVD), vascular endothelial growth factor (VEGF), thrombospodin1 (TSP1) and p53 protein with prognosis in epithelial ovarian cancer., Methods: Samples from 57 patients with primary epithelial ovarian cancer were examined by immunohistochemical staining using anti-VEGF, anti-TSP1, anti-p53 and anti-CD34 antibodies. The correlation of MVD, expression of VEGF, TSP1 and p53 protein with postoperative recurrence and overall survival were analyzed retrospectively., Results: VEGF, TSP1 and p53 protein was positively detected in 40 (70.2%), 27 (47.4%) and 35 (61.4%) of those patients, respectively. The mean MVD in this series was 30.3 +/- 8.5. High MVD, positive VEGF expression and negative TSP1 expression were positively correlated with postoperative recurrence. Univariate analysis showed that patients with high MVD, positive expression of VEGF and p53 had shorter median overall survival time than those with lower MVD, negative expression of VEGF and p53 (P = 0.0187, P = 0.010 and P = 0.005, respectively), while TSP1 expression was revealed as a protective factor for prognosis. Patients with positive expression of TSP1 had longer median overall survival time than those with negative TSP1 expression (P = 0.042). Multivariate analysis showed that MVD and p53 expression were two independent prognostic factors in epithelial ovarian cancer (P = 0.018 and P = 0.009, respectively)., Conclusion: VEGF, TSP1 and p53 protein may play an important role in the angiogenesis of epithelial ovarian cancer. High MVD level and p53 protein expression are two independent poor prognostic factors.

The study objective was to determine whether tumor vascularity correlates with patient survival, to compare newer semiautomated methods of angiogenesis assessment to older methods, and to determine if advanced image analysis methods can offer useful patient outcome data in serous ovarian cancer. Using the specific endothelial marker CD34, microvessel determinations were quantified in 132 serous ovarian tumors by manual counting at final magnifications of x 200 and x 400 in the most highly vascular areas. Computer-assisted image analysis microvessel counts, endothelial area estimates, and minimum spanning tree (MST) analysis of capillary architecture, which involves assessment of intercapillary distances, were correlated with traditional manual techniques.Manual, semiautomated, and advanced image analysis methods were found to be highly reproducible and express strong correlation with one another. Univariate cyclooxygenase analysis revealed angiogenesis parameters to be highly significant predictors for overall survival (OS) and disease-free survival. Multivariate cyclooxygenase analysis revealed maximum MST (P = 0.009), length MST (P = 0.005), 1 nearest neighbor (P

Introduction: The goal of this study is to evaluate the relation of maspin expression and its cellular localization to markers of angiogenesis in epithelial ovarian serous carcinoma (OSC)., Materials and Methods: We identified 118 patients with high-grade advanced stage OSC who were treated at our institution. Clinical data were collected, and immunohistochemistry (IHC) with antibodies to VEGF, CD34, COX-2, and maspin was performed on paraffin-embedded tumor blocks. CD34 immunostaining was used to determine microvessel density. The correlation between the various molecular markers was assessed using the Chi-square test. Survival analysis was computed using the Kaplan-Meier model, and various prognostic variables were compared using Cox regression analysis., Results: Maspin expression was noted in 81.4% (96/118) of tumors. Expression was localized to the nuclear compartment in 21.2% of cases, whereas 60.2% of cases showed evidence of cytoplasmic +/- nuclear expression. Tumors that exhibited nuclear maspin expression had lower VEGF and COX-2 expression than tumors with negative or cytoplasmic expression. Tumors with high nuclear maspin expression had lower mean MVD than those with low or negative expression. The median survival based on localization of maspin was 1146 days for those with negative tumors, 1803 days for those with nuclear maspin, and 637 days for those with cytoplasmic maspin (P < 0.001). In a Cox regression analysis, maspin localization was an independent prognostic factor., Conclusion: Maspin expression and localization seem to play a role in ovarian cancer angiogenesis and progression. High nuclear expression was associated with reduced markers of angiogenesis and prolonged survival.

High vascularization is noted in serous papillary ovarian tumors of a low malignancy grade, particularly in malignant serous ovarian tumors with low vascularization in benign neoplasms. Pronounced morphological changes in the vascular wall are found mainly in malignant tumors and tumors of a low malignancy grade where primitive blood vessels of a sinusoid type with a thin muscle wall prevail. Types of vascularization in the tumors studied are variable and this correlates with results of color doppler mapping.

To determine if the immunohistochemical expression of hyaluronan synthase (HAS) correlates with the clinicopathological manifestations or clinical outcomes of ovarian carcinoma, sections of tumor tissue from 33 ovarian cancer patients were immunostained by the avidin-biotin-peroxidase complex method using anti-HAS1, anti-HAS2, anti-HAS3 and anti-CD44 antibody. A section was defined as having positive expression when >50% of the tumor cells were intensely stained. The microvessel density, which was defined as the mean number of new vessels, was determined under light microscopy. In the 33 ovarian cancer cases, 12 cases had positive expression of HAS1, 21 cases had positive expression of HAS2 and 11 cases had positive expression of HAS3. The expression of HAS1, HAS2 and HAS3 was unrelated to the stage of disease. CD44 expression occurred more frequently in the HAS1-positive group than in the HAS1-negative group, but the expression of HAS2 and HAS3 was unrelated to CD44 expression. The microvessel density was higher in the HAS1-positive group than in the HAS1-negative group. But the microvessel density did not differ in relation to the expression of HAS2 and HAS3. In the 23 patients that received chemotherapy, the expression of HAS1, HAS2 and HAS3 was unrelated to the chemotherapy response. The overall survival time was longer in the HAS1-negative group than in the HAS1-positive group. However, the expression of HAS2 and HAS3 was unrelated to the overall survival time. These results suggest that HAS1 expression in ovarian cancer may be associated with disease progression through angiogenesis and is an independent predictor of patient survival.

Objectives: Ovarian neoplasms are very important problem in medicine, because they account for 23% of all female genital neoplasms, and they are the cause of 47% deaths among women suffering from gynecological cancers. Progression of neoplasmatic disease depends also on dynamism of angiogenesis, because better oxygen and nutrition substances supply increase tumor growth. To increase the tumor volume of 1 mm3, the development of new vessels is needed, and that also increases the risk of distant metastases., Aim: The aim of the study was the evaluation of clinical parameters compared with histological and laboratory findings in serous carcinomas. The research analyzed of angiogenesis level (antigen CD34) in patients with ovarian cancers and in control group., Materials and Methods: The material consisted of 41 cases of serous ovarian cancer. For clinical examinations we chose only patients who underwent primary surgical operation. The control group for CD34 levels were 15 patients with benign serous adenomas. The microscopic (200x) evaluation of blood vessel in paraffin samples were made by showing the reaction of endothelial CD34 antigen with DAKO serum (Monoclonal Mouse Anti Human CD34 class 1-N 1574 LSAB)., Results: The level of statistical significance for grading and total vessels' area was p = 0.01 (G1--0.037 mm2, G2--0.019 mm2, G3--0.015 mm2). No difference in vascularity was observed at the level of total vascularisation of serous ovarian cancers (0.021 mm2) and in benign serous adenomas (0.023 mm2)., Conclusions: Among analysed clinical and laboratory parameters only histological grade (G) correlates significantly with the level of vascularisation of ovarian serous cancers.

Objective: To elucidate the efficacy of TNP-470 on ovarian carcinomas by using cis-diamminedichloroplatinum (CDDP)-resistant cell lines., Methods: The susceptibility of human ovarian carcinoma-derived cell lines and its resistant cell lines against cis-diamminedichloroplatinum (CDDP) to angiogenesis inhibitor, TNP-470, were analyzed using three human cultured cell lines derived from ovarian carcinoma (TYK, KF-92, and Nakajima) and each CDDP-resistant cell line (TYK-R, TYK-R', KF/ra, KF/rb, Nakajima-S1, and Nakajima-S2)., Results: TNP-470 revealed suppression of thymidine incorporation by all of the nine cell lines linearly dependent on the concentration of TNP-470. Significant suppression was not observed for either uridine or leucine incorporation by all nine cell lines. To elucidate the site of each cell line, in which TNP-470 revealed the antitumor effect, the incorporation of (3)H-TNP-470 by cultured cells or by DNA extracted from cultured cells was examined in the cell lines, and the ratio of (3)H-TNP-470 incorporation by DNA to (3)H-TNP-470 incorporation by cultured cells ranged from 2.3% to 4.4% in three parent cell lines. The ratio in the CDDP-resistant cell lines ranged from 11.0% to 46.7%. The ability of TNP-470 to inhibit neoplastic growth in vivo was evaluated using KF-92, KF/ra, KF/rb, Nakajima, Nakajima-S1, and Nakajima-S2. Concerning KF-92, KF/ra, and KF/rb, 30 mg/kg of TNP-470 significantly suppressed the tumorigenicity of KF-92, 10 and 30 mg/kg of TNP-470 suppressed the tumorigenicity of KF/ra, and 30 mg/kg of TNP-470 suppressed the tumorigenicity of KF/rb. Concerning Nakajima, Nakajima-S1, and Nakajima-S2, TNP-470 revealed no inhibitory effect on the tumorigenicity of Nakajima. Contrary, significant inhibition was observed when 30 mg/kg of TNP-470 was used to the CDDP-resistant cell lines Nakajima-S1 and Nakajima-S2., Conclusion: These results suggest that the clinical application of TNP-470 may be one of the possible treatments for the CDDP-resistant ovarian carcinomas.

Metastasis or progression of ovarian cancer cells is known to be due to the action of various angiogenic factors. We determined the expression of thymidine phosphorylase/platelet-derived endothelial cell growth factor (TP/PD-ECGF) and vascular endothelial growth factor (VEGF) in cell lines established from 3 serous adenocarcinomas, 3 clear cell carcinomas and 2 mucinous carcinomas of the human ovary. TP activity and the TP mRNA level were much higher in the serous adenocarcinoma cells than in the clear cells and mucinous carcinoma cells, and TP expression was extremely low in the clear cell carcinoma cells. Expression of VEGF mRNA was variable, but not significantly different between the 3 histological types of ovarian cancer. In vivo angiogenesis in the ovarian cancer cells was evaluated by the dorsal air sac assay and revealed that SHIN-3 and HRA serous adenocarcinoma cells, which have high levels of TP expression, induced angiogenesis, while KK clear cell carcinoma cells with low TP expression, did not. The degree of ovarian-cancer-induced angiogenesis seemed to be independent of expression of VEGF in the cells. To confirm that the serous adenocarcinoma-induced angiogenesis is dependent on TP levels, a potent and specific inhibitor of TP was administered orally to mice implanted with a chamber containing SHIN-3 or HRA cells. The TP inhibitor significantly inhibited the angiogenesis induced by the serous adenocarcinoma cells. These results suggest that the angiogenic potency of ovarian cancer cells differs with the histological type and is controlled by expression of TP/PD-ECGF, not by VEGF, and that TP-mediated angiogenesis may be the main factor responsible for progression or metastasis of ovarian serous adenocarcinomas.

The role of vascular endothelial growth factor (VEGF) during peritoneal dissemination of ovarian carcinoma and the association with tumor microvessel density (MVD) and matrix metalloproteinase (MMP) activity was investigated. To this end, MVD, tumor tissue and ascitic fluid levels of VEGF, and MMP activity of ascitic fluid were examined in patients with ovarian cancer and benign ovarian tumor. The effect of ascites on cell growth, cell invasion activity and angiogenesis was investigated in vitro. Ascitic fluid and tumor tissue samples were obtained from 15 patients with benign ovarian tumor and 24 patients with ovarian carcinoma. Tissue extract and ascitic fluid levels of VEGF were measured using enzyme immunoassay. Tumor microvessels were detected immunohistochemically. MMP activity was measured by gelatin zymography. For the in vitro experiment, the SKOV-3 human ovarian carcinoma cell line was utilized. Cell growth was examined using MTT-assay, cell invasion activity was measured by Matrigel in vitro invasion assay, and neovascularization was assessed using an angiogenesis kit. VEGF levels in tissue extract and ascitic fluid, MVD, expression of active form MMP-2 in ascitic fluid and ascites volume were higher in ovarian cancer patients than in benign ovarian tumor patients. In addition, these were elevated in stage III and IV diseases compared to stage I and II diseases in ovarian cancer patients. MVD and expression of active form MMP-2 in ascitic fluid were closely correlated with VEGF level in tissue extracts, and MVD and ascites volume were closely correlated with VEGF level in ascitic fluid. Cell invasive activity and angiogenesis activity increased when cells were exposed to ascites. These increases were apparent when exposed to ascites obtained from ovarian cancer patients and were related to VEGF concentrations of ascitic fluid and expression of active form MMP-2 in ascitic fluid. The increased VEGF secreted from tumor cells is suggested to enhance tumor growth through angiogenesis, to produce ascites and to elevate ascitic VEGF concentrations and expression of active form MMP-2. The progression of peritoneal involvement may be induced by elevated VEGF and expression of active form MMP-2, followed by increased VEGF in the primary tumor. Control of VEGF in the primary tumor may become an effective strategy against peritoneal dissemination of ovarian carcinoma.

Vasculogenic mimicry reflects the plasticity of aggressive tumor cells that express vascular cell markers and line tumor vasculature; such has been demonstrated in aggressive ovarian carcinoma. This study measured the clinical significance of tumor cell-lined vasculature in ovarian carcinomas (n=77), which was detected in 23 (29.8%) tumors. The data show that tumor cell-lined vasculature was associated with aggressive tumor features and with shorter overall survival (p<0.001). Cox proportional hazards model revealed that tumor cell-lined vasculature (p=0.002) was independently associated with poor survival. This is the first study demonstrating the clinical implications of tumor cell-lined vasculature in ovarian carcinoma.

To investigate tumor angiogenesis in benign, borderline and malignant epithelial ovarian tumors and its relation with the pathogenesis of ovarian carcinoma, polycolonal antibody directed against human von Willebrand factor (factor VIII) was used to measure the microvessel density (MVD) in 66 cases (11 benign, 10 borderline, and 45 malignant) of epithelial ovarian tumors by using immunohistochemistry. The results showed that the mean MVD in epithelial ovarian cancer (31.7 +/- 11.2, 400 X) was higher than in benign and borderline tumors (16.7 +/- 6.3, 20.7 +/- 8.8 respectively, P < 0.05). There was no difference in MVDs among those in different tumor grades (P > 0.05). But there was significant difference in MVDs among those in different tumor stages (P < 0.05). MVD in stage III-IV cancer was higher than that in stage I-II (P < 0.05). It is concluded that the tumor angiogenesis is an early event in ovarian tumorgenesis. The increased tumor micovessel might be responsible for tumor development.

Aim: To determine whether three-dimensional power Doppler can improve the recognition of pelvic tumor morphology and angiogenesis., Methods: Using this technique we analyzed 180 adnexal masses and 110 uterine lesions. Tumor volume, morphology, and vascularity were evaluated in each patient. Irregular and randomly dispersed vessels with complex branching depicted by comprehensive three dimensional display were suggestive of pelvic malignancy, while linear-like vascular morphology, single vessel arrangement and regular branching were typical for benign structures., Results: Addition of qualitative analysis of vascular architecture of adnexal tumor to morphological parameters reached 96.15% sensitivity and 98.73% specificity. When endometrial lesions were prospectively analyzed, sensitivity and specificity were 91.67% and 98.49%, respectively. Because the lowest positive predictive value of 16.67% was obtained for myometrial lesions, this method should not be advised for their eva luation., Conclusion: Good results achieved by three dimensional ultrasound can be explained by improved recognition of the pelvic lesion anatomy, characterization of the surface features, detection of the tumor infiltration, and precise depiction of the size and volume. Three dimensional power Doppler imaging can detect structural abnormalities of the malignant tumor vessels, such as arteriovenous shunts, microaneurysms, tumoral lakes, disproportional calibration, coiling, and dichotomous branching. Therefore it enhances and facilitates the morphologic and functional evaluation of both benign and malignant pelvic tumors.

VEGF is an angiogenic factor with potent endothelial cell (EC) proliferative actions. Our aim was to investigate whether expression of VEGF and its receptors and EC proliferation differ between ovarian tumour types and regions of the vasculature. VEGF, VEGFR-1, VEGFR-2 and EC proliferation were examined immuno-histochemically, and in situ hybridisation (ISH) studies of VEGF mRNA expression were performed and assessed in regions of high (HVD) and average (AVD) vessel density. VEGF immunostaining was significantly stronger in HVD regions of malignant compared with borderline serous tumours. VEGF immunostaining did not differ between tumour types; however, the percentage of VEGFR-1- and VEGFR-2-positive vessels was significantly lower in mucinous tumours. No differences were observed between HVD and AVD regions. VEGF ISH signal was observed in 2/7 borderline mucinous tumours, 8/14 malignant serous tumours and 5/13 benign tumours. The EC proliferation index was significantly lower in the HVD regions of serous relative to benign tumours. A negative correlation between VEGFR-1 immunostaining and microvessel density was observed in benign and serous tumours. However, EC proliferation index and VEGFR-1 positivity were positively correlated in benign tumours. Our results suggest that VEGF may play a role in the control of angiogenesis in serous and benign tumours but it does not appear to contribute to the previously reported higher microvessel density in mucinous tumours or to influence heterogeneity of microvessel density in ovarian tumours.

Angiogenesis plays an important role in ovarian cancer growth and metastasis formation. Adenosine is one of the most potent stimulator of neovascularisation. The aim of present study was to determine if theobromine, adenosine receptor antagonist, influences angiogenic activity and proangiogenic cytokines production. Theobromine caused significant inhibition of angiogenic activity of ovarian cancer cells. In in vivo and in vitro cultures theobromine diminished vascular endothelial growth factor (VEGF) production. Production of basic fibroblast growth factor (bFGF) and interleukin-8 (IL-8) was not altered by the examined drug. These findings suggest that theobromine might be a potent inhibitor of angiogenesis induced by ovarian cancer cells and its mechanism of action is related to inhibition of VEGF production.

Vascular endothelial growth factor (VEGF) expression and microvessel density were studied in cases of advanced epithelial ovarian carcinoma to evaluate their usefulness as prognostic variables. Tumor samples from 18 patients with advanced stage serous epithelial ovarian cancer were evaluated for VEGF expression by reverse-transcriptase polymerase chain reaction (RT-PCR) analysis. Immunohistochemical study of corresponding archival tissues with an antibody to von Willebrand factor (vWF; FVIII-RA) was used for tumor microvessel count determinations. The correlation of VEGF expression and mean microvessel counts was determined by an unpaired t-test. Survival analysis for known prognostic factors and VEGF expression was performed. Survival distributions were calculated by the product limit of Kaplan and Meier and significant differences between distributions were analyzed with a log rank test. From the RT-PCR analysis of tumor VEGF expression, 12 samples were found to be strongly positive, whereas six samples had low/negative VEGF expression. The median survival was 60 months for the VEGF-low/negative group and 28 months for the VEGF-positive group (P = 0.058). Other prognostic variables had minimal impact on survival, i.e. age < 65 years (P = 0.873), FIGO stage (P = 0.06), grade (P = 0.236) and debulking status (P = 0.842). Fourteen of 18 tumor specimens were suitable for microvessel counting. The mean microvessel counts of the VEGF-positive group and the VEGF-negative group were 27/hpf and 35/hpf, respectively (P = 0.16). In this preliminary analysis, high VEGF expression in epithelial ovarian carcinomas was associated with poor overall survival. Further study will be necessary to elucidate the lack of association of VEGF expression and tumor microvessel counts.

It is now well established that unrestricted growth of tumors is dependent upon angiogenesis. However, previous studies on tumor growth have not yet revealed how the transition to an angiogenetic state in ovarian malignancy is reflected in the vascular architecture of the ovary. We report here our preliminary observations based upon three-dimensional imaging of normal and tumor-induced ovarian angiogenesis created with a computer-assisted three-dimensional interactive application. The findings suggest that tumor-induced angiogenesis creates a bizarre vascular architecture, with a possible link to chaotic behavior.