VEGF-A and i-NOS expression are prognostic factors in serous epithelial ovarian carcinomas after complete surgical resection

Expression of HIF-1α, Ki67, SMA and E-cadherin in endometriosis, endometrial and ovarian carcinoma

INTRODUCTION

Endometriosis is a benign gynecological condition that shares many characteristics with cancer cells, including immune evasion, survival, adhesion, invasion, and angiogenesis. The simultaneous investigation of tissue hypoxia, EMT, and proliferative index in endometriosis, endometrial, and ovarian carcinomas may provide new insight into the evolution and progression of gynecological neoplasms.

An angiogenic tumor phenotype predicts poor prognosis in ovarian cancer

OBJECTIVE

Epithelial ovarian cancer (OC) is the deadliest gynecological malignancy worldwide. Blocking angiogenesis with bevacizumab, an antibody targeting vascular endothelial growth factor (VEGF), shows efficacy in different lines of OC therapy. This study investigates the clinical impact of tumoral expression of angiogenesis-related genes and their association with bevacizumab response in OC in retrospective analysis of three independent cohorts.

METHODS

mRNA expression of seven angiogenic genes (VEGF, VEGFR2, PDGFA, PDGFB, PDGFRA, PDGFRB, KIT) was quantified in an inception OC cohort (n = 195) and a transcriptional tumor angiogenesis score from 0 to 3 was established and linked to progression-free survival (PFS) and overall survival (OS). This score was corroborated in an independent publicly available cohort from The Cancer Genome Atlas (TCGA, n = 582) and prediction of therapeutic efficacy of bevacizumab by the angiogenesis score was analyzed in the Gene Expression Omnibus (GEO) dataset GSE140082 (n = 380) from the ICON7-trial.

RESULTS

The tumor angiogenesis score prognosticated PFS and OS in patients with OC from the inception cohort (p < 0.001, respectively). Tumoral PDGFA expression (PFS: HR 2.46, p = 0.005; OS: HR 2.26, p = 0.011) and a high tumoral transcriptional angiogenesis score (PFS: HR 1.41, p = 0.018) were identified as independent predictors of clinical outcome. The transcriptional angiogenesis score exhibited a significant though smaller effect size on PFS in the TCGA cohort. However, in the ICON7-trial, the angiogenesis score was not associated with benefit of bevacizumab treatment.

CONCLUSIONS

Our study indicates that tumoral expression of angiogenic genes is unfavorable in OC. The established score could be used to identify patients who respond to targeted angiogenic therapies, a concept that warrants prospective controlled clinical trials.

Lubeluzole Repositioning as Chemosensitizing Agent on Multidrug-Resistant Human Ovarian A2780/DX3 Cancer Cells

In a previous paper, we demonstrated the synergistic action of the anti-ischemic lubeluzole (Lube S) on the cytotoxic activity of doxorubicin (Dox) and paclitaxel in human ovarian cancer A2780 and lung cancer A549 cells. In the present paper, we extended in vitro the study to the multi-drug-resistant A2780/DX3 cell line to verify the hypothesis that the Dox and Lube S drug association may potentiate the antitumor activity of this anticancer compound also in the context of drug resistance. We also evaluated some possible mechanisms underlying this activity. We analyzed the antiproliferative activity in different cancer cell lines. Furthermore, apoptosis, Dox accumulation, MDR1 downregulation, ROS, and NO production in A2780/DX3 cells were also evaluated. Our results confirm that Lube S improves Dox antiproliferative and apoptotic activities through different mechanisms of action, all of which may contribute to the final antitumor effect. Moderate stereoselectivity was found, with Lube S significantly more effective than its enantiomer (Lube R) and the corresponding racemate (Lube S/R). Docking simulation studies on the ABCB1 Cryo-EM structure supported the hypothesis that Lube S forms a stable MDR1-Dox-Lube S complex, which hampers the protein transmembrane domain flipping and blocks the efflux of Dox from resistant A2780/DX3 cells. In conclusion, our in vitro studies reinforce our previous hypothesis for repositioning the anti-ischemic Lube S as a potentiating agent in anticancer chemotherapy.

Impact of Secretion-Active Osteoblast-Specific Factor 2 in Promoting Progression and Metastasis of Head and Neck Cancer

Treatment success of head and neck cancer (HNC) is still hampered by tumor relapse due to metastases. Our study aimed to identify biomarkers by exploiting transcriptomics profiles of patient-matched metastases, primary tumors, and normal tissue mucosa as well as the TCGA HNC cohort data sets. Analyses identified osteoblast-specific factor 2 (OSF-2) as significantly overexpressed in lymph node metastases and primary tumors compared to normal tissue. High OSF-2 levels correlate with metastatic disease and reduced overall survival of predominantly HPV-negative HNC patients. No significant correlation was observed with tumor localization or therapy response. These findings were supported by the fact that OSF-2 expression was not elevated in cisplatin-resistant HNC cell lines. OSF-2 was strongly expressed in tumor-associated fibroblasts, suggesting a tumor microenvironment-promoting function. Molecular cloning and expression studies of OSF-2 variants from patients identified an evolutionary conserved bona fide protein secretion signal (1MIPFLPMFSLLLLLIVNPINA21). OSF-2 enhanced cell migration and cellular survival under stress conditions, which could be mimicked by the extracellular administration of recombinant protein. Here, OSF-2 executes its functions via ß1 integrin, resulting in the phosphorylation of PI3K and activation of the Akt/PKB signaling pathway. Collectively, we suggest OSF-2 as a potential prognostic biomarker and drug target, promoting metastases by supporting the tumor microenvironment and lymph node metastases survival rather than by enhancing primary tumor proliferation or therapy resistance.

Identification of cytokeratin24 as a tumor suppressor for the management of head and neck cancer

To improve management of head and neck squamous cell carcinoma patients, we need to increase our understanding of carcinogenesis, to identify biomarkers, and drug targets. This study aimed to identify novel biomarkers by providing transcriptomics profiles of matched primary tumors, lymph node metastasis, and non-malignant tissue of 20 HNSCC patients as well as by bioinformatic analyses of a TCGA HNSCC cohort, comprising 554 patients. We provide cancer cell signaling networks differentially expressed in tumors versus metastases, such as mesenchymal-epithelial transition, and structural integrity networks. As a proof of principle study, we exploited the data sets and performed functional analyses of a novel cytokeratin, cytokeratin24 (cKRT24), which had not been described as biomarker for tumors before. Survival analysis revealed that low cKRT24 expression correlated with poor overall survival in HNSCC. Experimentally, downregulation of cKRT24 in primary tumors, metastases, and HNSCC cell lines was verified on mRNA and protein level. Cloning and ectopic overexpression of cKRT24 not only affected viability and growth of HNSSC cell lines, but also inhibited tumor growth in murine xenograft studies. We conclude that cKRT24 functions as a tumor suppressor in HNSCC, and may serve as an additional prognostic biomarker and novel target to support current HNSCC treatments.

Cytokines as Prognostic Biomarkers of Epithelial Ovarian Cancer (EOC): A Systematic Review and Meta-Analysis

OBJECTIVES

The value of cytokines as epithelial ovarian cancer (EOC) prognostic factors has been widely investigated. This study aimed to determine the role of single cytokine as a biomarker prognosis in EOC.

MATERIALS AND METHODS

We conducted a systematic review and meta-analysis of studies reporting cytokine as the prognostic predictor in EOC based on PRISMA guideline. We included English articles investigating associations of preoperative cytokines level in tissue, blood or ascites with overall survival (OS) or disease-free survival (DFS) from PUBMED and EBSCO. Summary hazard ratios (HRs) and confidence intervals (CIs) were calculated.

RESULTS

Fifty studies investigating twenty types of cytokines in tumor tissue, serum, and ascites from 5,376 patients were included. Pre-operative high VEGF level was associated with poor OS (HR 2.28, 95%CI [1.28, 3.28]) and DFS (HR 2.13, 95%CI [1.63, 2.78]) in serum and OS (HR 1.80, 95%CI [1.45, 2.23]) in tissue. IL-6 level in blood was associated with DFS (HR 1.60, 95%CI [1.21, 2.11]). There was no single cytokine which investigated by at least 2 studies reporting hazard ratio in ascites, so we did not conduct the meta-analysis. Other cytokines (serum IL-8; ascites fluid IL-8, IL-10, IFN-γ, TNF-α; and ovarian tissue TGF-α, CSF-1, IL-10 ,TGF-β1, IL-17) associated with the poorer prognosis, could not be pooled due to lack of studies.

CONCLUSION

Pre-operative VEGF level in serum and tissue specimen seem to be the potential candidate of an unfavorable prognostic biomarker for EOC. The evidence was lacking to support the other cytokines investigated in blood, tissue and ascites as prognostic biomarkers for EOC.

High expression of Tie-2 predicts poor prognosis in primary high grade serous ovarian cancer

Background

Antiangiogenic therapy, although part of standard treatment in ovarian cancer, has variable efficacy. Furthermore, little is known about the prognostic biomarkers and factors influencing angiogenesis in cancer tissue. We evaluated the expression of angiopoietin-2 and two endothelial tyrosine kinase receptors, Tie-1 and Tie-2, and assessed their value in the prediction of survival in patients with malignant epithelial ovarian cancer. We also compared the expression of these factors between primary high grade serous tumors and their distant metastasis.

Materials and methods

We evaluated 86 women with primary epithelial ovarian cancer. Matched distal omental metastasis were investigated in 18.6% cases (N = 16). The expression levels of angiogenic factors were evaluated by immunohistochemistry in 306 specimens and by qRT-PCR in 111 samples.

Results

A high epithelial expression level of Tie-2 is a significant prognostic factor in primary high grade serous ovarian cancer. It predicted significantly shorter overall survival both in univariate (p<0.001) and multivariate survival analyses (p = 0.022). Low angiopoietin-2 expression levels in primary ovarian tumors were significantly associated with shorter overall survival (p = 0.015) in the univariate survival analysis. A low expression of angiopoietin-2 was also significantly related to high grade tumors, size of residual tumor after primary surgery and the recurrence of cancer (p = 0.008; p = 0.012; p = 0.018) in the whole study population. The expression of angiopoietin-2 and Tie-2 was stronger in distal omental metastasis than in primary high grade serous tumors in matched-pair analysis (p = 0.001; p = 0.002).

Conclusions

The angiogenic factor, angiopoietin-2, and its receptor Tie-2 seem to be significant prognostic factors in primary epithelial ovarian cancer. Their expression levels are also increased in metastatic lesions in comparison with primary tumors.

Assessing the predictive response of a simple and sensitive blood-based biomarker between estrogen-negative solid tumors

PURPOSE

We investigated N^w-hydroxy l-Arginine (NOHA) predictive response in serous ovarian carcinoma based on estrogen-hormone receptor expression status; and assessed the distinctive NOHA response between estrogen-receptor-negative (ER-) tumor subtypes of ovarian and breast cancer.

MATERIALS/METHODS

Three-dimensional (3D) spheroids models of ER- and estrogen-receptor-positive (ER+) from breast and ovarian tumor, cultured for 9 weeks, were assayed for cellular levels of inducible nitric oxide synthase (NOS2), nitric oxide (as total nitrite) and l-Arginine, and compared to NOHA in culture medium. Statistical difference was set at p < 0.01.

RESULTS

Nine-week in vitro studies showed a progressive NOHA reduction in culture medium by at least 0.4-0.8 fold, and 0.65-0.92 fold only in the ER- breast tumor and ER- ovarian tumor 3D spheroids, respectively; with increases in cellular NOS2 and nitric-oxide levels, by at least 1.0-2.45 fold in both ER- tumor subtype 3D spheroids (p < 0.01; n = 6). Within ER- subtypes, medium NOHA decreased by ≥ 38.9% in ovarian cancer over breast cancer 3D-spheroids, with cellular increases in NOS2 (by ≥ 17.4%), and nitric oxide (by ≥ 18.8%). Cellular l-Arginine to medium NOHA ratio was higher, and by at least 6.5-22.5 fold in ER- breast tumor 3D-spheroids, and at least 10-70 fold in ER- ovarian tumor 3D spheroids, than in ER+ and control conditions; and was ≥48% higher in ER- ovarian cancer than in ER- breast cancer 3D-spheroids.

CONCLUSIONS

The present study shows NOHA as a sensitive and selective indicator differentiating and distinguishing ER- subtypes based on the tumor grade.

Yangjing Capsule Can Improve the Function of the Testicular Angiogenesis through Activating VEGFA/eNOS Signaling Pathway

Background

The testicular microcirculation was an important aspect of testicular physiology and it offered a stable environment for the transport of nutrients and secretary products in the testis. Yangjing capsule (YC), a traditional Chinese compound herbal prescription, has been proved as an effective drug to ameliorate spermatogenesis, promote testosterone synthesis in vivo, and cure spermatogenesis in clinical practice.

Objective

This study was aimed at understanding the potential mechanisms of YC exerting angiogenic effects in the mouse spermatogenesis dysfunction model induced by cyclophosphamide (CP) and MLTC-1 cells.

Materials and Methods

Balb/c mice were randomly divided into five groups: control, CP, CP plus YC (630 mg/kg), CP plus YC (1260 mg/kg), and CP plus YC (2520 mg/kg). After 30 days, mice were sacrificed and the expressions of endothelial marker CD34+, angiogenic marker VEGFA, VEGFR1, VEGFR2, and eNOS in the testes of the mice were examined; moreover, Leydig cell line MLTC-1 cells were cultured and treated with different concentrations of YC extracts (YCE), and the expressions of VEGFA, VEGFR1, VEGFR2, and eNOS, as well as the secretion of NO, were evaluated.

Results

We observed that YC significantly increased the expressions of VEGFA, VEGFR1, VEGFR2, and eNOS in testes of CP-treated mice; moreover, YCE has led to increased expressions of VEGFA, VEGFR1, VEGFR2, and eNOS and secretion of NO in MLTC-1 in vitro. These data suggested that the YC might be an alternative treatment for the dysfunction of testicular microcirculation by promoting the angiogenesis in the testis.

Expression profiles of VEGF-A, VEGF-D and VEGFR1 are higher in distant metastases than in matched primary high grade epithelial ovarian cancer

Background

In many malignancies including ovarian cancer, different angiogenic factors have been related to poor prognosis. However, data on their relations to each other or importance as a prognostic factor in ovarian cancer is missing. Therefore, we investigated the expressions of VEGF-A, VEGF-C, and VEGF-D, and the receptors VEGFR1, VEGFR2, and VEGFR3 in patients with malignant epithelial ovarian neoplasms. We further compared expression levels between primary tumors and related distant omental metastases.

Methods

This study included 86 patients with malignant ovarian epithelial tumors and 16 related distant metastases. Angiogenic factor expression was evaluated using immunohistochemistry (n = 102) and qRT-PCR (n = 29).

Results

Compared to primary high grade serous ovarian tumors, the related omental metastases showed higher expressions of VEGF-A (p = 0.022), VEGF-D (p = 0.010), and VEGFR1 (p = 0.046). In univariate survival analysis, low epithelial expression of VEGF-A in primary tumors was associated with poor prognosis (p = 0.024), and short progression-free survival was associated with high VEGF-C (p = 0.034) and low VEGFR3 (p = 0.002). The relative expressions of VEGF-D, VEGFR1, VEGFR2, and VEGFR3 mRNA determined by qRT-PCR analyses were significantly correlated with the immunohistochemically detected levels of these proteins in primary high grade serous ovarian cancer and metastases (p = 0.004, p = 0.009, p = 0.015, and p = 0.018, respectively).

Conclusions

The expressions of VEGF receptors and their ligands significantly differed between malignant ovarian tumors and paired distant metastases. VEGF-A, VEGF-D, and VEGFR1 protein expressions seem to be higher in distant metastases than in the primary high grade serous ovarian cancer lesions.

The Potential Role of iNOS in Ovarian Cancer Progression and Chemoresistance

Inducible nitric oxide synthase (iNOS), the enzyme responsible for nitric oxide (NO) production, is not present in most cells under normal conditions. The expression of its mRNA, as well as its protein synthesis and full enzymatic activity, undergoes multilevel regulation including transcriptional and posttranscriptional mechanisms, the availability of iNOS substrate and cofactors and oxygen tension. However, in various malignant diseases, such as ovarian cancer, the intracellular mechanisms controlling iNOS are dysregulated, resulting in the permanent induction of iNOS expression and activation. The present review summarizes the multistaged processes occurring in normal cells that promote NO synthesis and focuses on factors regulating iNOS expression in ovarian cancer. The possible involvement of iNOS in the chemoresistance of ovarian cancer and its potential as a prognostic/predictive factor in the course of disease development are also reviewed. According to the available yet limited data, it is difficult to draw unequivocal conclusions on the pros and cons of iNOS in ovarian cancer. Most clinical data support the hypothesis that high levels of iNOS expression in ovarian tumors are associated with a greater risk of disease relapse and patient death. However, in vitro studies with various ovarian cancer cell lines indicate a correlation between a high level of iNOS expression and sensitivity to cisplatin.

Comparison of Mean VEGF-A Expression Between Acute Ischemic Stroke Patients and Non-Ischemic Stroke Subjects

BACKGROUND

Glucose and oxygen supply to neurons are disrupted during acute ischemic stroke, resulting in hypoxia. This event, in turn, activates the transcription of hypoxia-inducible factor (HIF-1), which is responsible for activating genes responsible for angiogenesis, including vascular endothelial growth factor (VEGF). VEGF and their receptor systems exert complex mechanisms of angiogenesis, including the stimulator, inhibitors, angiogenic and modulator. VEGF-A is the primary regulator of angiogenesis, both during physiological and pathological conditions. Nevertheless, the role of VEGF on the prognosis of hypoxia remains controversial.

AIM

The purpose of this study was to address if there is any difference between the mean expression of VEGF-A between acute ischemic patients and non-ischemic stroke subjects.

METHODS

This was an observational study with a cross-sectional design, the population in this research is the acute ischemic stroke patients and non-ischemic stroke subjects, which were admitted on Emergency Room and later treated in the Stroke Unit, Dr Sardjito General Hospital, Yogyakarta, Indonesia. Subjects were recruited using the purposive method, yielding a total of 64 subjects on both groups. Diagnosis of acute ischemic stroke was established using a head CT scan. Patients who meet the inclusion criteria and willing to participate in the study were asked to provide informed consent. Laboratory analysis was conducted during the first 24 hours after being treated at Stroke Unit, Dr Sardjito General Hospital, Yogyakarta, Indonesia, with venous blood was withdrawn VEGF-A levels between acute ischemic stroke and non-ischemic stroke subjects were subsequently compared. Categorical variables (including gender) were tested using either chi-square or Fisher exact test. Interval data was examined using student t-test if data distribution was normal.

RESULTS

As many as 35 acute ischemic stroke and 35 non-ischemic stroke patients were included in the study, among whom were 18 men (51.43%) and 17 women (48.57%) among stroke patients and 21 (60%) men and 14 (40%) women among subjects without stroke. The average of the subject's age on stroke and non-ischemic stroke group was 58.51 and 48.57 years old. VEGF-A levels were significantly higher in the non-stroke group (561.77 ± 377.92) compared with stroke group (397.78 ± 181.53) with p = 0.02.

CONCLUSION

expression of VEGF-A in acute ischemic stroke group was lower when compared with the non-stroke group.

Vascular endothelial growth factor receptor 2 (VEGFR2) correlates with long-term survival in patients with advanced high-grade serous ovarian cancer (HGSOC): a study from the Tumor Bank Ovarian Cancer (TOC) Consortium

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.

The relationship of the angiogenesis regulators VEGF-A, VEGF-R1 and VEGF-R2 to p53 status and prognostic factors in epithelial ovarian carcinoma in FIGO-stages I-II

The aim of this study was to evaluate prognostic effect of the angiogenesis regulators VEGF-R1, VEGF-R2 and VEGF-A for recurrent disease and disease-free survival (DFS), and their relation to the apoptosis regulator p53, in 131 patients with FIGO-stages I-II with epithelial ovarian cancer. For the detection of positivity of the markers the techniques of tissue microarrays and immunohistochemistry (IHC) were used. In tumors the frequency of positive staining for VEGF-R1 was 19%, for VEGF-R2 and VEGF-A, it was 77 and 70%, respectively. Positivity for p53 was detected in 25% of tumors. The total number of recurrences in the complete series was 34 out of 131 (26%) and 5-year disease-free survival (DFS) was 68%. Positive staining for VEGF-A (P=0.030), VEGF-R2 (P=0.011) and p53 (P=0.015) was found more frequently in type II tumors than in type I tumors. Patients with VEGF-R1 negative tumors had worse (P=0.021) DFS compared to patients with VEGF-R1 positive tumors. In two multivariate Cox analyzes with DFS as endpoint, FIGO-stage (HR=3.8), VEGF-R2 status (HR=0.4) and p53 status (HR=2.3), all were significant and independent prognostic factors. When the variables VEGF-R2 and p53 were replaced with the new variable VEGF-R2+p53-/other three combinations in one group, it was found that patients from that subgroup had 86% reduced risk of dying in disease (HR=0.24). Findings above, confirmed relationship between VEGF-R2 and VEGF-A and p53, respectively, with regard to recurrent disease and survival. Some findings from the present study are different from results from previous studies on the regulation of angiogenesis. Despite many trials with anti-angiogenic agents in the front line of ovarian cancer have shown to be positive for progression-free survival, no one has demonstrated an impact on overall survival. Therefore, one of the greatest challenges in ovarian cancer research, is to discover predictive and prognostic biomarkers.

The homeoprotein DLX4 controls inducible nitric oxide synthase-mediated angiogenesis in ovarian cancer

Background

Homeobox genes encode transcription factors that control patterning of virtually all organ systems including the vasculature. Tumor angiogenesis is stimulated by several homeobox genes that are overexpressed in tumor cells, but the mechanisms of these genes are poorly understood. In this study, we investigated the mechanisms by which DLX4, a homeobox gene that is associated with increased tumor microvessel density, stimulates ovarian tumor angiogenesis.

Methods

Expression of DLX4 and nitric oxide synthases was analyzed in publicly available transcriptional profiles of ovarian cancer clinical specimens. Levels of inducible nitric oxide synthase (iNOS) were evaluated by quantitative RT-PCR, flow cytometry and nitric oxide assays using ovarian cancer cell lines in which DLX4 was overexpressed or knocked down. Signal Transducer and Activator of Transcription 1 (STAT1) expression and activity were evaluated by luciferase reporter assays, immunofluorescence staining, Western blot and immunoprecipitation. Endothelial cell growth and tumor angiogenesis were evaluated in in vitro assays and xenograft models.

Results

We identified that DLX4 induces expression of iNOS, an enzyme that stimulates angiogenesis by generating nitric oxide. Analysis of datasets of two independent patient cohorts revealed that high DLX4 expression in ovarian cancer is strongly associated with elevated expression of iNOS but not of other nitric oxide synthases. Studies using STAT1-expressing and STAT1-deficient cells revealed that DLX4 interacts with STAT1 and induces iNOS expression in part by stimulating STAT1 activity. Expression of DLX4 in ovarian cancer cells stimulated endothelial cell growth in vitro and increased microvessel density in xenograft models, and these stimulatory effects of DLX4 were abrogated when its induction of iNOS was inhibited.

Conclusion

These findings indicate that DLX4 promotes ovarian tumor angiogenesis in part by stimulating iNOS expression.

Electronic supplementary material

The online version of this article (doi:10.1186/s12943-015-0368-3) contains supplementary material, which is available to authorized users.

Doxorubicin synergizes with 34.5ENVE to enhance antitumor efficacy against metastatic ovarian cancer

PURPOSE

Novel therapeutic regimens are needed to improve dismal outcomes associated with late-stage ovarian cancer. Oncolytic viruses are currently being tested in patients with ovarian cancer. Here, we tested the therapeutic efficacy of combining doxorubicin with 34.5ENVE, an oncolytic herpes simplex virus transcriptionally driven by a modified stem cell-specific nestin promoter, and encoding for antiangiogenic Vasculostatin-120 (VStat120) for use against progressive ovarian cancer.

EXPERIMENTAL DESIGN

Antitumor efficacy of 34.5ENVE was assessed in ovarian cancer cell lines, mouse ascites-derived tumor cells, and primary patient ascites-derived tumor cells by standard MTT assay. The ability of conditioned medium derived from 34.5ENVE-infected ovarian cancer cells to inhibit endothelial cell migration was measured by a Transwell chamber assay. Scope of cytotoxic interactions between 34.5ENVE and doxorubicin were evaluated using Chou-Talalay synergy analysis. Viral replication, herpes simplex virus receptor expression, and apoptosis were evaluated. Efficacy of oncolytic viral therapy in combination with doxorubicin was evaluated in vivo in the murine xenograft model of human ovarian cancer.

RESULTS

Treatment with 34.5ENVE reduced cell viability of ovarian cancer cell lines, and mouse ascites-derived and patient ascites-derived ovarian tumor cells. Conditioned media from tumor cells infected with 34.5ENVE reduced endothelial cell migration. When combined with doxorubicin, 34.5ENVE killed synergistically with a significant increase in caspase-3/7 activation, and an increase in sub-G1 population of cells. The combination of doxorubicin and 34.5ENVE significantly prolonged survival in nude mice bearing intraperitoneal ovarian cancer tumors.

CONCLUSIONS

This study indicates significant antitumor efficacy of 34.5ENVE alone, and in combination with doxorubicin against disseminated peritoneal ovarian cancer.

Vascular endothelial growth factor (VEGF) polymorphism and increased risk of epithelial ovarian cancer

INTRODUCTION

Angiogenesis (AG) is essential for epithelial ovarian cancer (EOC) development. Vascular endothelial growth factor (VEGF), encoded by the VEGF gene, and endostatin, the product of the COL18A1 gene, act as a potent promoter and an inhibitor of AG, respectively. In the present study, we tested whether VEGF C936T and COL18A1 D104N polymorphisms alter the risk of EOC.

METHODS

Genomic DNA from 131 EOC patients and 137 controls were analyzed by polymerase chain reaction and restriction fragment length polymorphism methods. The differences between groups were analyzed by χ (2) or Fisher's exact test and logistic regression analysis.

RESULTS

The frequency of the VEGF 936CC genotype was higher in patients than in controls (84.8% vs. 75.3%, P = 0.03). Individuals with respective genotypes had a 1.98 (95% CI 1.04-3.78)-fold increased risk of EOC than those with the remaining genotypes. An excess of VEGF 936CC plus COL18A1 DN genotype was seen in patients when compared to controls (48.6% vs. 30.5%); however, only a tendency toward a statistically significant difference in genotype frequencies was found in the study (P = 0.06), reflecting a trend toward an increased risk of 2.44 for EOC in carriers of the combined genotype.

CONCLUSION

Our data present, for the first time, preliminary evidence that VEGF C936T alone or combined with the COL18A1 D104N polymorphism of AG constitutes an important inherited EOC determinant.

Dual inhibition of the vascular endothelial growth factor pathway: a phase 1 trial evaluating bevacizumab and AZD2171 (cediranib) in patients with advanced solid tumors

BACKGROUND

The current study was conducted to evaluate the safety and biological activity of dual inhibition of the vascular endothelial growth factor (VEGF) pathway with combined bevacizumab and cediranib (a VEGF receptor tyrosine kinase inhibitor).

METHODS

This was a 3 + 3 dose escalation study in patients with advanced solid tumors. Cediranib was given orally daily for 21 days and bevacizumab intravenously every 2 weeks. Pharmacokinetics and correlates (nitric oxide synthase, nitrate oxide, and circulating tumor cells) were assessed.

RESULTS

Fifty-one patients were treated. Dose-limiting toxicities (DLTs) (grade 3-4; graded according to the National Cancer Institute Common Terminology Criteria of Adverse Events [version 3.0]) observed included 1 patient with chest pain, 1 patient with fatigue, 2 patients with thrombocytopenia, 3 patients with hypertension (1 with intracranial hemorrhage), and 1 patient with grade 5 hemoptysis. Moreover, 2 patients presented with grade 3 intracranial bleeding beyond the DLT window. Dose level 2 (cediranib at a dose of 20 mg/day and bevacizumab at a dose of 5 mg/kg every 2 weeks) was selected as the recommended phase 2 dose (RP2D); 17 patients were treated at dose level 2 with 1 DLT and no intracranial bleeding or severe hypertension reported. Pharmacokinetics of cediranib at dose level 3 demonstrated a 46% to 77% increase in area under the curve (0-24 hours) on cycle 1 day 1 compared with historical controls. Four patients attained partial remissions: inflammatory breast cancer (-54%), basal cell carcinoma (-33%), alveolar soft part sarcoma (-33%), and synovial sarcoma (-32%). Patients with a lower circulating tumor cell count (< 30) at the predose period had a longer time to tumor progression (P = .024, log-rank test).

CONCLUSIONS

Cediranib at a dose of 20 mg/day and bevacizumab at a dose of 5 mg/kg every 2 weeks was found to be the RP2D. Activity in several tumor types was noted. Central nervous system bleeding and severe hypertension were observed at doses above the RP2D.

Discovery of fruquintinib, a potent and highly selective small molecule inhibitor of VEGFR 1, 2, 3 tyrosine kinases for cancer therapy

VEGF/VEGFR signal axis has been proven to be an important target for development of novel cancer therapies. One challenging aspect in small molecular VEGFR inhibitors is to achieve sustained target inhibition at tolerable doses previously seen only with the long-acting biologics. It would require high potency (low effective drug concentrations) and sufficient drug exposures at tolerated doses so that the drug concentration can be maintained above effective drug concentration for target inhibition within the dosing period. Fruquintinib (HMPL-013) is a small molecule inhibitor with strong potency and high selectivity against VEGFR family currently in Phase II clinical studies. Analysis of Phase I pharmacokinetic data revealed that at the maximum tolerated dose of once daily oral administration fruquintinib achieved complete VEGFR2 suppression (drug concentrations were maintained above that required to produce >85% inhibition of VEGFR2 phosphorylation in mouse) for 24 hours/day. In this article, the preclinical data for fruquintinib will be described, including kinase enzyme activity and selectivity, cellular VEGFR inhibition and VEGFR-driven functional activity, in vivo VEGFR phosphorylation inhibition in the lung tissue in mouse and tumor growth inhibition in a panel of tumor xenograft and patient derive xenograft models in mouse. Pharmacokinetic and target inhibition data are also presented to provide a correlation between target inhibition and tumor growth inhibition.

The prognostic value of vascular endothelial growth factor in ovarian cancer: a systematic review and meta-analysis

OBJECTIVE

The prognostic role of vascular endothelial growth factor (VEGF) in ovarian cancer remains inconclusive. This meta-analysis aimed to explore the association between VEGF overexpression and survival outcomes in ovarian cancer patients.

METHODS

Studies were identified from PubMed and EMBASE searches performed on January 2nd, 2011. After careful review, survival data were extracted from eligible studies. A meta-analysis was performed to generate combined hazard ratio (HR) for progression-free survival (PFS) and overall survival (OS) in serum and tumor tissue studies.

RESULTS

Sixteen studies with 1111 patients were analyzed. Elevated serum VEGF was significantly associated with poor PFS [HR 2.46, 95% CI (1.84, 3.29)] and OS [HR 2.21, 95% CI (1.57, 3.13)]. No significant heterogeneity existed in serum studies. Similarly, tissue VEGF overexpression was associated with poor PFS [HR 1.63, 95% CI (1.09, 2.42)] and OS [HR 1.70, 95% CI (1.01, 2.87)]. However, significant heterogeneity was found in tissue studies, with I(2) of 44% for PFS and 64% for OS. Studies were stratified into subgroups by International Federation of Gynecology and Obstetrics (FIGO) stages. Subgroup analyses showed that high tissue VEGF was significantly associated with shorter PFS [HR 5.34, 95% CI (1.95, 14.59)] and OS [HR 6.13, 95% CI (2.47, 15.26)] in studies where predominantly early-stage patients were included, but not in studies with a majority of advanced-stage patients. Subgroup analysis was not performed in serum studies because all those studies enrolled more patients in advanced stages than early stages.

CONCLUSIONS

Overexpression of VEGF in primary tumor and serum associates with poor PFS and OS for patients with ovarian cancer. The association between high tissue VEGF level and poor prognosis exists in early stage patients, but not in advanced stage patients.

Prognostic biomarkers in ovarian cancer

Epithelial ovarian cancer (EOC) remains the most lethal gynecological malignancy despite several decades of progress in diagnosis and treatment. Taking advantage of the robust development of discovery and utility of prognostic biomarkers, clinicians and researchers are developing personalized and targeted treatment strategies. This review encompasses recently discovered biomarkers of ovarian cancer, the utility of published prognostic biomarkers for EOC (especially biomarkers related to angiogenesis and key signaling pathways), and their integration into clinical practice.

The influence of nitric oxide synthase 2 on cutaneous wound angiogenesis

BACKGROUND

Inducible nitric oxide synthase (nitric oxide synthase 2, NOS 2) inhibition significantly suppresses chronically ischaemic skin flap survival, possibly because of reduced angiogenesis.

OBJECTIVES

To investigate the effect of genetic NOS 2 inhibition on cutaneous wound angiogenesis in two in vivo murine models. The impact of NOS 2 manipulation on vascular endothelial growth factor (VEGF)-A stimulated and fibroblast growth factor (FGF)-2 stimulated angiogenesis was also investigated in the Matrigel(®) plug assay.

METHODS

(i) Matrigel plugs/incisional wounds: two groups of NOS 2-/- mice and two groups of wild-type (WT) mice had bilateral Matrigel plugs containing 500 ng mL(-1) VEGF-A or 1000 ng mL(-1) FGF-2 injected subcutaneously in the abdomen. A 2·5 cm long dorsal incisional skin wound was created and sutured closed in the same animals. Wounds and plugs were explored at 7 or 12 days. (ii) Excisional wounds: dorsal 0·5 × 1·0 cm excisional skin wounds were created in four groups (two NOS 2-/- and two WT) and explored at 7 or 14 days. Wounds and Matrigel plugs were examined histologically and morphometrically for determination of percentage vascular volume (PVV).

RESULTS

The PVV in NOS 2-/- incisional wounds and excisional wounds was significantly less than in WT wounds (P = 0·05 and P < 0·001, respectively). The PVV was significantly less in VEGF-A stimulated Matrigel plugs compared with FGF-2 stimulated plugs in NOS 2-/- mice (P < 0·01), but not in WT mice.

CONCLUSIONS

NOS 2 is significantly involved in angiogenic signalling in healing skin wounds, particularly within the first 7 days. However, Matrigel plug vascularization suggests that the role of NOS 2 in angiogenesis is related to VEGF-A but not FGF-2 stimulated angiogenesis.

Utility of vascular endothelial growth factor inhibitors in the treatment of ovarian cancer: from concept to application

Despite recent advances in the management of ovarian cancer, it remains the most lethal gynecologic malignancy. Vascular endothelial growth factor (VEGF) has been shown to play a pivotal role in the progression of ovarian cancer leading to the eventual development of malignant ascites. On this basis, agents rendering VEGF ineffective by neutralizing VEGF (bevacizumab), blocking its receptors (aflibercept), or interfering with the postreceptor signaling pathways (sunitinib) provide us with the rational treatment options. These agents are generally used in combination with the standard chemotherapeutic drugs. Here, we discuss the basis of and the logic behind the use of these agents in the treatment of epithelial ovarian cancer, as well as their evaluation in different preclinical and clinical studies.

Molecular typing of epithelial ovarian carcinomas using inflammatory markers

BACKGROUND

Ovarian epithelial carcinomas have recently been classified as slow growing type I tumors and rapidly growing highly aggressive type II tumors. The present study sought to molecularly characterize type I and II tumors using known molecular markers.

METHODS

Specimens from 213 patients with ovarian carcinoma were categorized as type I or type II, and evaluated by immunohistochemistry for the inflammatory markers glucose transporter protein-1 (Glut-1), inducible nitric oxide synthase (iNOS), cyclooxygenase-1 (COX-1), cyclooxygenase-2 (COX-2), and nuclear factor kappa B. Statistical analysis was performed to investigate whether these molecular markers could distinguish between type I and type II tumors. Kaplan-Meier survival curves and COX regression analysis were used to determine the prognostic effect of these markers on survival in the 2 types of tumors.

RESULTS

Overexpression of COX-1, COX-2, iNOS, and Glut-1 was significantly higher in type II tumors (P < .05). Women with type II tumors had a poorer median survival (60 months) as compared with those with type I tumors (141 months) (P = .0001). Multivariate analysis revealed type II tumors, late stage, and age >60 years as significant predictors of poor survival. For type II tumors, median survival of patients with tumors overexpressing COX-2 was 44 compared with 85 months for those with tumors with low COX-2 expression (P = .029). Looking at both type I and II tumors, the number of markers simultaneously overexpressed in each tumor was a significant predictor of poor patient survival (P = .005).

CONCLUSIONS

The present study demonstrates that the new proposed histologic classification of ovarian epithelial carcinomas correlates with a distinct expression of inflammatory pathway proteins. High expression of these markers may explain the different biologic behavior of these 2 tumor types and provide targets for therapy.

Predictive and prognostic protein biomarkers in epithelial ovarian cancer: recommendation for future studies

Epithelial ovarian cancer is the most lethal gynecological malignancy. Due to its lack of symptoms, this disease is diagnosed at an advanced stage when the cancer has already spread to secondary sites. While initial rates of response to first treatment is >80%, the overall survival rate of patients is extremely low, mainly due to development of drug resistance. To date, there are no reliable clinical factors that can properly stratify patients for suitable chemotherapy strategies. Clinical parameters such as disease stage, tumor grade and residual disease, although helpful in the management of patients after their initial surgery to establish the first line of treatment, are not efficient enough. Accordingly, reliable markers that are independent and complementary to clinical parameters are needed for a better management of these patients. For several years, efforts to identify prognostic factors have focused on molecular markers, with a large number having been investigated. This review aims to present a summary of the recent advances in the identification of molecular biomarkers in ovarian cancer patient tissues, as well as an overview of the need and importance of molecular markers for personalized medicine in ovarian cancer.

Angiogenesis and ovarian cancer

Ovarian carcinoma is the most important cause of gynaecological cancer-related mortality in Western societies. The age at diagnosis, extent of disease (as expressed by FIGO state), success of primary surgery and the histopathological features of the tumour are important prognostic markers. The majority of patients with ovarian cancer present with advanced disease (FIGO stage III/IV) and in this group of patients the median survival is only three years. New treatment approaches are therefore required to improve outcome in this disease. Angiogenesis, the development of a neovascular blood supply, is a critical step in the propagation of malignant tumour growth and metastasis and represents a promising target. This review will focus on angiogenesis, VEGF biology and the potential value of angiogenic factors with prognostic value in ovarian cancer.