Activity of bevacizumab (rhuMAB VEGF) in advanced refractory epithelial ovarian cancer

Past and present: a bibliometric study on the treatment of recurrent ovarian cancer

Background

Ovarian cancer (OC) is a gynecological malignancy with a high mortality rate worldwide. The unfavorable prognosis of OC is mainly attributed to the recurrent propensity. Recently, mortality from OC has exhibited a downward trend. These favorable patterns are likely to be driven by advancements in novel therapeutic regimens. However, there is a lack of visualize analysis of the application of these new drugs on women with recurrent OC (ROC). Therefore, we aimed to provide a bibliometric analysis of the evolving paradigms in the ROC treatment.

Methods

Documents on ROC treatment were systematically collected from the MEDLINE database and Web of Science Core Collection (WOSCC). The retrieved documents were exported in the plain text file format, and files were named and saved to the paths specified by the Java application. Microsoft Excel (version 2010), Citespace (6.2.R4) and VOSviewer (1.6.19) were used for data analysis, and included the following: 1) annual publication trend; 2) contributions of countries, institutions and authors; 3) co-citation of journals and references; and 4) co-occurrence of keywords.

Results

A total of 914 documents published in the MEDLINE and 9,980 ones in WOSCC were retrieved. There has been an upward trend in the productivity of publications on ROC treatment on by years. The United States was the leading contributor in this field, and the University of Texas System stood out as the most productive institution. Giovanni Scambia and Maurie Markman were the research leaders in the field of ROC treatment. The journal Gynecologic Oncology had the highest citation frequency. The reference entitled with "Niraparib Maintenance Therapy in Platinum-Sensitive, Recurrent Ovarian Cancer" got highest centrality of 0.14 in the co-citation network. Keyword analysis revealed that the focus of current ROC treatment was on platinum-based anticancer drugs, paclitaxel, angiogenesis inhibitors (AIs), immune checkpoint inhibitors (ICIs) and poly (ADP-ribose) polymerase inhibitors (PARPis).

Conclusion

Scholars from a multitude of countries have been instrumental in the advancement of ROC treatment. The research hotspots and trend in the field of predominantly originated from leading international journals and specialized periodicals focused on gynecologic oncology. Maintenance therapy using AIs or (and) PARPis has emerged as a significant complement to platinum-based chemotherapy for patients with ROC.

Dual targeting ovarian cancer by Muc16 CAR T cells secreting a bispecific T cell engager antibody for an intracellular tumor antigen WT1

Epithelial ovarian cancer is the most lethal of gynecological cancers. The therapeutic efficacy of chimeric antigen receptor (CAR) T cell directed against single antigens is limited by the heterogeneous target antigen expression in epithelial ovarian tumors. To overcome this limitation, we describe an engineered cell with both dual targeting and orthogonal cytotoxic modalities directed against two tumor antigens that are highly expressed on ovarian cancer cells: cell surface Muc16 and intracellular WT1. Muc16-specific CAR T cells (4H11) were engineered to secrete a bispecific T cell engager (BiTE) constructed from a TCR mimic antibody (ESK1) reactive with the WT1-derived epitope RMFPNAPYL (RMF) presented by HLA-A2 molecules. The secreted ESK1 BiTE recruited and redirected other T cells to WT1 on the tumor cells. We show that ESK1 BiTE-secreting 4H11 CAR T cells exhibited enhanced anticancer activity against cancer cells with low Muc16 expression, compared to 4H11 CAR T cells alone, both in vitro and in mouse tumor models. Dual orthogonal cytotoxic modalities with different specificities targeting both surface and intracellular tumor-associated antigens present a promising strategy to overcome resistance to CAR T cell therapy in epithelial ovarian cancer and other cancers.

Vascular normalization: reshaping the tumor microenvironment and augmenting antitumor immunity for ovarian cancer

Ovarian cancer remains a challenging disease with limited treatment options and poor prognosis. The tumor microenvironment (TME) plays a crucial role in tumor growth, progression, and therapy response. One characteristic feature of the TME is the abnormal tumor vasculature, which is associated with inadequate blood perfusion, hypoxia, and immune evasion. Vascular normalization, a therapeutic strategy aiming to rectify the abnormal tumor vasculature, has emerged as a promising approach to reshape the TME, enhance antitumor immunity, and synergize with immunotherapy in ovarian cancer. This review paper provides a comprehensive overview of vascular normalization and its potential implications in ovarian cancer. In this review, we summarize the intricate interplay between anti-angiogenesis and immune modulation, as well as ICI combined with anti-angiogenesis therapy in ovarian cancer. The compelling evidence discussed in this review contributes to the growing body of knowledge supporting the utilization of combination therapy as a promising treatment paradigm for ovarian cancer, paving the way for further clinical development and optimization of this therapeutic approach.

Dual targeting ovarian cancer by Muc16 CAR-T cells secreting a bispecific T cell engager antibody for an intracellular tumor antigen WT1

Epithelial ovarian cancer is the most lethal of gynecological cancers. The therapeutic efficacy of chimeric antigen receptor (CAR) T cell directed against single antigens is limited by the heterogeneous target antigen expression in epithelial ovarian tumors. To overcome this limitation, we describe an engineered cell with both dual targeting and orthogonal cytotoxic modalities directed against two tumor antigens that are highly expressed on ovarian cancer cells: cell surface Muc16 and intracellular WT1. Muc16-specific CAR-T cells (4H11) were engineered to secrete a bispecific T cell engager (BiTE) constructed from a TCR mimic antibody (ESK1) reactive with the WT1-derived epitope RMFPNAPYL (RMF) presented by HLA-A2 molecules. The secreted ESK1 BiTE recruited and redirected other T cells to WT1 on the tumor cells. We show that ESK1 BiTE-secreting 4H11 CAR-T cells exhibited enhanced anticancer activity against cancer cells with low Muc16 expression, compared to 4H11 CAR-T cells alone, both in vitro and in mouse tumor models. Dual orthogonal cytotoxic modalities with different specificities targeting both surface and intracellular tumor-associated antigens present a promising strategy to overcome resistance to CAR-T cell therapy in epithelial ovarian cancer and other cancers.

Neo-vascularization-based therapeutic perspectives in advanced ovarian cancer

The process of angiogenesis is well described for its potential role in the development of normal ovaries, and physiological functions as well as in the initiation, progression, and metastasis of ovarian cancer (OC). In advanced stages of OC, cancer cells spread outside the ovary to the pelvic, abdomen, lung, or multiple secondary sites. This seriously limits the efficacy of therapeutic options contributing to fatal clinical outcomes. Notably, a variety of angiogenic effectors are produced by the tumor cells to initiate angiogenic processes leading to the development of new blood vessels, which provide essential resources for tumor survival, dissemination, and dormant micro-metastasis of tumor cells. Multiple proangiogenic effectors and their signaling axis have been discovered and functionally characterized for potential clinical utility in OC. In this review, we have provided the current updates on classical and emerging proangiogenic effectors, their signaling axis, and the immune microenvironment contributing to the pathogenesis of OC. Moreover, we have comprehensively reviewed and discussed the significance of the preclinical strategies, drug repurposing, and clinical trials targeting the angiogenic processes that hold promising perspectives for the better management of patients with OC.

MSLN Correlates With Immune Infiltration and Chemoresistance as a Prognostic Biomarker in Ovarian Cancer

Mesothelin (MSLN) is a glycoprotein with various expression degrees in different tumors including mesothelioma, ovarian cancer, pancreatic cancer, etc. MSLN is considered to play an important role in cell survival, proliferation, and tumor progression. Although the expression of MSLN in tumors makes it a potential therapeutic target, its mechanism of action is still unclear, especially its correlation with immune cells infiltration in the tumor microenvironment has not been investigated. In this study, we detected the overexpression of MSLN in ovarian cancer using database analysis and tissue-array staining. We further evaluated the diagnostic value of MSLN and found it was associated with poor overall survival in ovarian cancer. In addition, the high expression of MSLN was significantly related to the immune-related genes and chemoresistant genes. We confirmed the overexpression of MSLN in the chemoresistant ovarian cancer cell lines. Our research suggests that MSLN participates in a variety of pathways related to the suppression of immune activation and promotion of chemoresistance, leading to a poor prognosis in ovarian cancer.

Mesothelin-Specific CAR T Cells Target Ovarian Cancer

New therapeutic options for patients with ovarian cancer are urgently needed. Therefore, we evaluated the efficacy of two second-generation mesothelin (MSLN)-directed CAR T cells in orthotopic mouse models of ovarian cancer. Treatment with CAR T cells expressing an MSLN CAR construct including the CD28 domain (M28z) significantly prolonged survival, but no persistent tumor control was observed. Despite lower response rates, MSLN-4-1BB (MBBz) CAR T cells induced long-term remission in some SKOV3-bearing mice. Tumor-infiltrating M28z and MBBz CAR T cells upregulated PD-1 and LAG3 in an antigen-dependent manner while MSLN+ tumor cells expressed the corresponding ligands (PD-L1 and HLA-DR), demonstrating that coinhibitory pathways impede CAR T-cell persistence in the ovarian tumor microenvironment. Furthermore, profiling plasma soluble factors identified a cluster of M28z- and MBBz-treated mice characterized by elevated T-cell secreted factors that had increased survival, higher CD8+ T-cell tumor infiltration, less exhausted CAR T-cell phenotypes, and increased HLA-DR expression by tumor cells. Altogether, our study demonstrates the therapeutic potential of MSLN-CAR T cells to treat ovarian cancer. SIGNIFICANCE: These findings demonstrate that MSLN-directed CAR T cells can provide antitumor immunity against ovarian cancer.

Novel monoclonal antibody against integrin α3 shows therapeutic potential for ovarian cancer

Ovarian cancer has a high recurrence rate after platinum‐based chemotherapy. To improve the treatment of ovarian cancer and identify ovarian cancer‐specific antibodies, we immunized mice with the human ovarian carcinoma cell line, SKOV‐3, and generated hybridoma clones. Several rounds of screening yielded 30 monoclonal antibodies (mAbs) with no cross‐reactivity to normal cells. Among these mAbs, OV‐Ab 30‐7 was found to target integrin α3 and upregulate p53 and p21, while stimulating the apoptosis of cancer cells. We further found that binding of integrin α3 by OV‐Ab 30‐7 impaired laminin‐induced focal adhesion kinase phosphorylation. The mAb alone or in combination with carboplatin and paclitaxel inhibited tumor progression and prolonged survival of tumor‐bearing mice. Moreover, immunohistochemical staining of ovarian patient specimens revealed higher levels of integrin α3 in cancer cells compared with normal cells. By querying online clinical databases, we found that elevated ITGA3 expression in ovarian cancer is associated with poor prognosis. Taken together, our data suggest that the novel mAb, OV‐Ab 30‐7, may be considered as a potential therapeutic for ovarian cancer.

The Epigenetic Landscape in the Treatment of Gynecologic Malignancies

The care of patients with advanced-stage or recurrent endometrial, ovarian, and cervical cancer remains clinically challenging. Despite the identification of novel therapeutics and advancements in supportive care, survival outcomes have been relatively unchanged over the past decade. In addition to established genomic alterations and the contributions of the tumor microenvironment to cancer progression, epigenetic mechanisms have emerged as important contributors to gynecologic cancer progression. DNA methylation, histone modification, and noncoding RNA expression may be important contributors to disease initiation and progression and may represent novel therapeutic targets. This article reviews the epigenetic landscape of endometrial, ovarian, and cervical cancer, describing the state of the science and discussing potential clinical applications. To date, the role of epigenetic drugs in the treatment of gynecologic cancers remains unclear, although continued progress may inform future treatment modalities.

The role of bevacizumab in targeted vascular endothelial growth factor therapy for epithelial ovarian cancer: an updated systematic review and meta-analysis

The impact of bevacizumab (an anti-vascular endothelial growth factor therapy) remains uncertain, which has been the focus of studies on the management of epithelial ovarian cancer (EOC). To investigate the efficacy of bevacizumab combinations with different regimens in the treatment of patients with EOC, a meta-analysis of Phase III randomized controlled trials was conducted. The databases searched included PubMed, Embase, ClinicalTrials.gov, Chinese Knowledge Infrastructure, as well as the Cochrane Central Register of Controlled Trials. After evaluation of quality, a meta-analysis of valid extracted data was performed using Review Manager (RevMan) software. Five studies with 4,369 patients were included. Bevacizumab plus chemotherapy improved progression-free survival (hazard ratio [HR] =0.63; 95% confidence interval [CI], 0.51-0.77; P<0.01) and overall survival (HR =0.91; 95% CI, 0.84-0.99; P<0.05). Interestingly, in patients with a high risk of progression, the subgroups that received bevacizumab combined with different regimens of chemotherapy showed a significant improvement with paclitaxel plus carboplatin-based chemotherapy (HR =0.86; 95% CI, 0.77-0.95; P<0.01), but not with non-paclitaxel plus carboplatin-based chemotherapy (HR =0.91; 95% CI, 0.77-1.07; P>0.05) in overall survival. The combination of bevacizumab and paclitaxel plus carboplatin-based regimens offers a new treatment option for women with EOC, especially in those with a high risk of progression.

Bevacizumab in ovarian cancer: A critical review of phase III studies

Bevacizumab (BV) is a humanized monoclonal antibody targeting vascular endothelial growth factor and it is the first molecular-targeted agent to be used for the treatment of ovarian cancer (OC). Randomized Phase III trials evaluated the combination of BV plus standard chemotherapy for first-line treatment of advanced OC and for platinum-sensitive and platinum-resistant recurrent OC. These trials reported a statistically significant improvement in progression-free survival but not in overall survival. Furthermore, BV effectively improved the quality of life with regard to abdominal symptoms in recurrent OC patients. Bevacizumab is associated with adverse events such as hypertension, bleeding, thromboembolism, proteinuria, delayed wound healing, and gastrointestinal events. However, most of these events can be adequately managed. This review describes the latest evidence for BV treatment of OC and selection of patients for personalized treatment.

Bevacizumab-Based Chemotherapy Combined with Regional Deep Capacitive Hyperthermia in Metastatic Cancer Patients: A Pilot Study

As an angiogenesis inhibitor, bevacizumab has been investigated in combination with different chemotherapeutic agents, achieving an established role for metastatic cancer treatment. However, potential synergic anti-angiogenic effects of hyperthermia have not tested to date in literature. The aim of our study was to analyze efficacy, safety, and survival of anti-angiogenic-based chemotherapy associated to regional deep capacitive hyperthermia (HT) in metastatic cancer patients. Twenty-three patients with metastatic colorectal (n = 16), ovarian (n = 5), and breast (n = 2) cancer were treated with HT in addition to a standard bevacizumab-based chemotherapy regimen. Treatment response assessment was performed, according to the modified Response Evaluation Criteria for Solid Tumors (mRECIST), at 80 days (timepoint-1) and at 160 days (timepoint-2) after therapy. Disease Response Rate (DRR), considered as the proportion of patients who had the best response rating (complete response (CR), partial response (PR), or stable disease (SD)), was assessed at timepoint-1 and timepoint-2. Chi-squared for linear trend test was performed to evaluated the association between response groups (R/NR) and the number of previous treatment (none, 1, 2, 3), number of chemotherapy cycles (<6, 6, 12, >12), number of hyperthermia sessions (<12, 12, 24, >24), and lines of chemotherapy (I, II). Survival curves were estimated by Kaplan-Meier method. DRR was 85.7% and 72.2% at timepoint-1 and timepoint-2, respectively. HT was well tolerated without additional adverse effects on chemotherapy-related toxicity. Chi-squared for linear trend test demonstrated that the percentage of responders grew in relation to the number of chemotherapy cycles (p = 0.015) and to number of HT sessions (p < 0.001) performed. Both overall survival (OS) and time to progression (TTP) were influenced by the number of chemotherapy cycles (p < 0.001) and HT sessions (p < 0.001) performed. Our preliminary data, that need to be confirmed in larger studies, suggest that the combined treatment of bevacizumab-based chemotherapy with HT has a favorable tumor response, is feasible and well tolerated, and offers a potentially promising option for metastatic cancer patients.

The Significance of VSIG4 Expression in Ovarian Cancer

OBJECTIVES

The protein V-set and Ig domain-containing 4 (VSIG4), a novel B7 family-related macrophage protein with the capacity to inhibit T-cell activation, has a potential role in cancer. Here we suggest its possibility as a therapeutic target and prognostic biomarker of ovarian cancer.

METHODS

Between January 2011 and June 2015, tumor tissues and peripheral blood samples were obtained during surgery from 10 patients with benign ovarian tumors and 22 patients with ovarian cancers. Messenger RNA and protein expression levels of VSIG4 in benign tumor and cancer tissues were examined by the reverse transcription polymerase chain reaction and Western blot, respectively. Soluble VSIG4 concentrations were measured by an enzyme-linked immunosorbent assay. The correlation between VSIG4 expression and the prognosis of ovarian cancer was analyzed according to the patients' clinicopathologic characteristics.

RESULTS

VSIG4 messenger RNA and protein expression levels in ovarian cancer tissues were higher than those in benign ovarian tumors (P = 0.0013 and 0.0001, respectively). Soluble VSIG4 concentrations were increased in patients with ovarian cancer compared with that in patients with benign ovarian tumors (P = 0.0452). Moreover, soluble VSIG4 levels were significantly increased in advanced-stage and recurrent ovarian cancer (P = 0.0244 and 0.0288, respectively). High VSIG4 expression of cancer tissue and low VSIG4 expression of plasma (soluble VSIG4) were associated with a longer disease-free interval (P = 0.0246 and 0.0398, respectively).

CONCLUSIONS

VSIG4 is overexpressed in ovarian cancers compared with that in benign tumors. This finding supports VSIG4 being used as a potential therapeutic target for ovarian cancer. Furthermore, soluble VSIG4 levels are associated with the progression and recurrence of ovarian cancer, indicating that soluble VSIG4 may be used as a potential biomarker for predicting tumor prognosis.

Efficacy of Postoperative Hormone Replacement Therapy on Prognosis of Patients with Serous Ovarian Carcinoma

Background:

Ovarian cancer is the most common cause of gynecological cancer-associated death. Iatrogenic menopause might adversely affect the quality of life and health outcomes in young female cancer survivors. We evaluated whether postoperative hormone replacement therapy (HRT) had a negative influence on the progression-free survival (PFS) of patients with papillary serous ovarian cancer (SOC).

Methods:

We retrospectively reviewed the medical records of patients with papillary SOC, treated from January 1980 to December 2009, who suffered from menopause with or without HRT. Clinical characteristics of patients were compared between the two groups (HRT and non-HRT). Blood samples were collected from all the participants to detect serum cancer antigen (CA) 125. Hazard ratios with 95% confidential intervals for each variable were calculated by univariable and multivariable conditional Logistic regression analyses.

Results:

Among 112 identified patients, 31 were HRT users and 81 were not. The two groups did not significantly differ in median age at diagnosis (t = 0.652, P = 0.513), International Federation of Gynecology and Obstetrics (FIGO) stage (χ² = 0.565, P = 0.754), differentiation (χ² = 1.728, P = 0.422), resection status (χ² = 0.070, P = 0.791), relapse (χ² = 0.109, P = 0.741), chemotherapy course (t = −1.079, P = 0.282), follow-up interval (t = 0.878, P = 0.382), or PFS (t = 0.580, P = 0.562). Median Kupperman score at the onset of HRT was 30.81 and 12.19 after the therapy (t = 3.302, P = 0.001). According to the analysis, the strongest independent variables in predicting PFS were FIGO stage and disease that was not optimally debulked.

Conclusions:

Postoperative HRT is not a prognostic factor for PFS of patients with papillary SOC. However, multicenter studies are needed to verify and extend our findings.

The management of malignant ascites and impact on quality of life outcomes in women with ovarian cancer

Malignant ascites is one of the most common sequela of epithelial ovarian cancer. It causes significant symptoms and can have a detrimental impact on patient quality of life, especially in women with recurrent ovarian cancer. The management of symptomatic ascites consists of both mechanical treatments that aim to drain the peritoneal cavity, and medical therapies that prevent and diminish the development of ascites. Mechanical options include serial paracentesis, peritoneal catheters, and peritoneovenous shunts. Pharmaceutical treatments include diuretics, angiogenesis inhibitors, and other targeted agents. There is a perception, without formal analysis, that intractable ascites is less common in the taxane era of therapy. In this review paper, we highlight current and emerging therapeutic strategies, complications and contraindications, and their effects on patient quality of life.

Anti-angiogenic agents in ovarian cancer: past, present, and future

Angiogenesis plays a pivotal role in normal ovarian physiology as well as in the progression of ovarian cancer through ascites formation and metastatic spread. Bevacizumab (Avastin(®), Genentech; South San Francisco, CA, USA), a humanized anti-vascular endothelial growth factor (VEGF) monoclonal antibody, is the most widely studied anti-angiogenesis agent both across tumor types and specifically in epithelial ovarian cancer. In 2005, single-agent bevacizumab at 15 mg/kg (IV) every 3 weeks was first reported to be active in a case of recurrent high-grade serous ovarian cancer after failing 11th line cytotoxic treatment. Since then, many case series, phase II and phase III trials have confirmed these results leading to regulatory approval in most countries including the US Food and Drug Administration in 2014. Guidelines now give clear recommendations as to when and how bevacizumab should be integrated into the ovarian cancer treatment paradigm. Other anti-VEGF agents such as the VEGF receptor (VEGFR) tyrosine kinase inhibitors have not shown increased activity or reduced toxicity relative to bevacizumab. However, anti-angiogenics other than anti-VEGF/VEGFR agents such as those targeting Angiopoietin-1 and -2 are in development as well as novel combinations with vascular disrupting agents (VDAs), PARP inhibitors and immune checkpoint inhibitors. Clearly, the benefits of anti-angiogenic agents such as bevacizumab must be carefully weighed against the cost and associated toxicities. Although almost all patients with ovarian cancer will receive an anti-angiogenic compound, cures are not increased. Predictive biomarkers are an urgent unmet need.

The Clinicopathologic Characteristics and 5-year Survival Rate of Epithelial Ovarian Cancer in Yazd, Iran

Introduction

Ovarian cancer is the second most common malignancy in women, the most common cause of gynecologic cancer deaths, and most patients have advanced stage disease at the time of diagnosis. The purpose of this study was to estimate the 5-year survival of patients with epithelial ovarian cancer based on age, tumor histology, stage of disease, and type of treatment.

Methods

This study was conducted on 120 patients with epithelial ovarian cancer referred to Shahid Sadoughi hospital and Shah Vali oncology clinic of Yazd from 2006 to 2012. Demographic data and patient records were studied to evaluate the treatment outcome, pathology of the tumor, and stage of disease. Finally, the overall survival rate and tumor-free survival of patients was assessed.

Results

The mean patient age was 53.87± 14.11 years. Most participants had stage I (36.7%) or stage II (35%) disease. Serous adenocarcinoma (57.6%) was the most common pathology found in patients with epithelial ovarian cancer. The overall survival of patients in this study was significantly associated with the histological tumor type (p = 0.000) and disease stage (p = 0.0377). Stage I (84.18%) and serous adenocarcinoma (72.81%) demonstrated the best survival. The tumor-free survival rates were not associated with histology types (p = 0.079), surgical procedure (p = 0.18), or chemotherapy (p = 0.18).

Conclusion

The survival of patients with epithelial ovarian cancer was significantly associated with disease stage. Serous adenocarcinoma also had the best prognosis among the pathologies studied. Therefore, early detection of ovarian cancer can substantially increase the survival rate.

Integrating bevacizumab into the management of epithelial ovarian cancer: the controversy of front-line versus recurrent disease

Angiogenesis plays a fundamental role in the pathogenesis of ovarian cancer. Vascular endothelial growth factor (VEGF) expression has been associated with the development of malignant ascites and tumor progression. Bevacizumab (Avastin(®); Genentech, South San Francisco, CA, USA), a humanized anti-VEGF monoclonal antibody, is the most widely studied antiangiogenesis agent across tumor types and specifically in epithelial ovarian cancer (EOC). With the recent reporting of four consecutive positive randomized trials adding bevacizumab to chemotherapy in the treatment of both front-line (GOG 218 and ICON7) and recurrent EOC ['platinum-resistant' (AURELIA Trial) or 'platinum-sensitive' (OCEANS Trial)], the most debatable question today is thus not IF we should treat ovarian cancer patients with bevacizumab, but WHEN. As bevacizumab is active in both settings, it seems appropriate to carefully consider this clinical controversy: 'what is the optimal setting for bevacizumab treatment?' A fine balance of efficacy, toxicity, quality of life, and symptom control is the main crux of this controversy. The cost effectiveness of bevacizumab in EOC is also controversial.

B7-H4 as a potential target for immunotherapy for gynecologic cancers: a closer look

B7-H4 is a transmembrane protein that binds an unknown receptor on activated T cells resulting in inhibition of T-cell effector function via cell cycle arrest, decreased proliferation, and reduced IL-2 production. B7-H4 is up-regulated on the surface of cancer cells and immunosuppressive tumor-associated macrophages (TAMs) in a variety of human cancers. Notably, B7-H4 expression levels inversely correlate with patient survival in ovarian cancer, making B7-H4 an attractive candidate for therapeutic intervention. Here, we summarize the experimental data and methodologies that have revealed B7-H4's mRNA and protein expression and function in both mice and humans since its discovery in 2003, with a specific focus on B7-H4's role in ovarian cancer. We also underscore the discrepancies in published data due to high variability in methodology and use of different antibodies, most of which are not commercially available. Finally, since B7-H4 is expressed on tumor cells and TAMs in various cancer types, directing therapeutics against B7-H4 could have tremendous synergistic outcomes in favorably altering the tumor micro-environment and eliminating cancer cells. We highlight the therapeutic potential of targeting B7-H4, both by comparing other negative immune modulators such as PD-1 and CTLA-4 and by identifying novel methods to target B7-H4 directly or indirectly to overcome B7-H4-mediated T-cell inhibition.

Incorporation of anti-angiogenesis therapy in the management of advanced ovarian carcinoma--mechanistics, review of phase III randomized clinical trials, and regulatory implications

Despite survival gains achieved nearly two decades ago with combination platinum- and taxane-based intravenous chemotherapy, overall survival curves have remained relatively unchanged during the 21st century using newer cytotoxic agents. Although combined intravenous-intraperitoneal (IV-IP) chemotherapy is promising, tolerability remains a significant issue. An emphasis has been placed on exploring dose dense schedules and targeted agents. Vascular endothelial growth factor (VEGF) has emerged as an important therapeutic target in several solid tumors including ovarian carcinoma. The monoclonal antibody, bevacizumab, binds VEGF, thus preventing activation of the VEGF receptor (VEGFR) leading to inhibition of tumor angiogenesis. To date eight phase 3 randomized controlled trials incorporating anti-angiogenesis therapy in the treatment of newly diagnosed and recurrent ovarian carcinoma have met their primary endpoints. Four of these trials included bevacizumab and were reported from 2010 to 2012. During 2013, the other four studies were reported, each studying one of the following novel anti-angiogenesis agents: pazopanib, cediranib, trebananib, and nintedanib. Importantly, none of these drugs have been approved by the United States Food and Drug Administration (US FDA) for the treatment of ovarian cancer. The purpose of this review will be to highlight both VEGF-dependent and non-VEGF dependent angiogenic pathways in ovarian cancer and discuss the phase 3 experiences and regulatory implications of targeting the tumor microenviroment with anti-angiogenesis therapy.

Epithelial cell-adhesion molecule-directed trifunctional antibody immunotherapy for symptom management of advanced ovarian cancer

Despite advances in cytotoxic chemotherapy and surgical cytoreduction, disease recurrence continues to be a troubling problem in patients with advanced-stage epithelial ovarian cancer (EOC). Malignant ascites affects approximately 10% of patients with recurrent EOC and is associated with troublesome symptoms, including abdominal pressure, distension, dyspnea, pelvic pain, and bowel/bladder dysfunction. To date, no effective therapy has been identified for the treatment of malignant ascites in patients with recurrent, advanced-stage ovarian cancer. Recently, immune modulation has gained attention as a novel approach to anti-cancer therapy. This review explores the role of epithelial cell-adhesion molecule (EpCAM)-directed immunotherapy, with a specific focus on the mechanism of action of the trifunctional antibody catumaxomab (anti-EpCAM × anti-CD3). In addition, clinical trials exploring the use of catumaxomab in the treatment of malignant ascites in patients with ovarian cancer are reviewed.

Angiogenesis inhibitors in the treatment of epithelial ovarian cancer

Treatment of epithelial ovarian cancer involves surgical management with staging or debulking surgery and chemotherapy with a platinum and taxane-containing regimen. Despite achieving a 70-80 % complete remission, patients often will recur. Novel therapies are needed to improve the treatment of ovarian cancers. Tumor angiogenesis is a critical process involved in the growth and metastasis of ovarian cancer. Numerous phase II trials with angiogenesis inhibitors have been reported and have led to the development and completion of several recent phase III trials in both upfront and recurrent ovarian cancers. Future studies will need to focus on how and when to incorporate angiogenesis inhibitors in the treatment armamentarium for ovarian cancers.

The contribution of catumaxomab in the treatment of malignant ascites in patients with ovarian cancer: a review of the literature

The approval of the first specific drug catumaxomab for the treatment of malignant ascites is the subject of this review. This trifunctional antibody is known to kill EpCAM-positive tumor cells and therefore attacks the primary cause of malignant ascites formation in the peritoneal cavity. Until today catumaxomab is the only EpCam-targeted antibody approved by the European Medicines Agency. Ovarian cancer is caused by epithelial tumors cells which overexpress epithelial cell adhesion molecule (EpCAM). The existing literature concerning the use of catumaxomab for the treatment of malignant ascites associated with ovarian cancer until today is reported in this article. It is very encouraging that different prospective studies from diverse scientific teams recently presented positive results concerning the efficacy and the safety of catumaxomab in the treatment of malignant ascites in patients with ovarian cancer. A case of a patient with ovarian cancer FIGO IIIc is also referred in this article. A complete remission and stable disease was found after 4 i.p. infusions of catumaxomab.

A phase II trial of docetaxel and bevacizumab in recurrent ovarian cancer within 12 months of prior platinum-based chemotherapy

OBJECTIVES

The efficacy and safety of bevacizumab and docetaxel were evaluated in women who developed recurrent epithelial ovarian, fallopian, or peritoneal cancer within 12 months of platinum-based therapy.

METHODS

Patients received docetaxel (40 mg/m(2)) on days 1 and 8 and bevacizumab (15 mg/kg) on day 1 of a 21-daycycle. Primary endpoint was 6-month progression-free survival (PFS).

RESULTS

Forty-one patients were evaluable for PFS and 38 for best response; 46% had platinum-free intervals (PFI) of <6 months and 54% between 6 and 12 months. The 6-month PFS was 43.9% (95% confidence interval (CI(95%))=28.6-58.2%). Median PFS (months) was 5.2 (CI(95%)=4.4-7.2) for all patients, 6.2 (CI(95%)=4.1-7.4) for patients with PFI <6 months, and 5.1 (CI(95%)=3.0-7.2) for those with PFI ≥ 6 months. Twenty-two patients showed overall response (CR+PR) (57.9%; CI(95%)=40.8-73.7%), and 32 showed clinical benefit (CR+PR+SD) (84.2%; CI(95%)=68.8-94.0%). For those with complete or partial responses, median duration of response was 4.8 months (0.7-14.5). Median overall survival was 12.4 months (CI(95%)=10.0-21.9). The most common grade 3/4 adverse events (AEs) were neutropenia (14.6% of patients), followed by leukopenia, fatigue, metabolic, and gastrointestinal, with 66% showing any grade 3/4 toxicity. Most common AEs of any grade were gastrointestinal (93%), fatigue (73%), and pain (73%). Four (10%) patients developed hypertension, 1 a gastrointestinal perforation, and another a colovesicular fistula.

CONCLUSIONS

Bevacizumab and docetaxel administered in patients with recurrent ovarian cancer is an active regimen without new unanticipated toxicities. This combination should be an option for further study or clinical use in recurrent ovarian cancer.

Contemporary use of bevacizumab in ovarian cancer

INTRODUCTION

Ovarian cancer remains the most lethal gynecologic malignancy. Although standard platinum-based chemotherapy results in high response rates, more than 70% of patients with advanced disease will experience recurrence within 5 years. Therefore, novel treatment strategies to increase primary efficacy, decrease recurrence after primary treatment and improve the response rate for recurrent disease are needed.

AREAS COVERED

This review covers antiangiogenesis therapy and the efficacy of bevacizumab as primary treatment and in platinum-sensitive and resistant recurrent disease.

EXPERT OPINION

The evidence provided from Phase III trials has supported the efficacy of bevacizumab in primary and recurrent ovarian cancer management. Future investigation is needed to improve clinical performance (via biomarkers of efficacy, early discontinuation, additional agents, etc.), as well as, more sensitive tools to assess direct patient impact.

Incidence and management of gastrointestinal perforation from bevacizumab in advanced cancers

Bevacizumab (Avastin™, Genentech) is a monoclonal antibody that deactivates the vascular endothelial growth factor leading to disruption of vital cancer signaling pathways and inhibition of angiogenesis which results in its anti-tumor activity. The use of bevacizumab in treating cancers has steadily increased since it was initially approved by the Food and Drug Administration for metastatic colorectal cancer. Clinical trials have revealed that bevacizumab has serious side effects, including spontaneous bowel perforation, which can occur in patients who have no involvement of the gastrointestinal tract by cancer. Although risk factors for bevacizumab-associated bowel perforation have been identified, it is still unclear which patients are specifically at risk for this complication. The management of bevacizumab-induced bowel perforation depends on the clinical presentation and the goals of care set by the treating physicians and the patient.

Emerging treatment options for management of malignant ascites in patients with ovarian cancer

Malignant ascites affects approximately 10% of patients with recurrent epithelial ovarian cancer and is associated with troublesome symptoms, including abdominal pressure and distension, dyspnea, bloating, pelvic pain, and bowel/bladder dysfunction. To date, no effective therapy has been identified for the treatment of malignant ascites in patients with recurrent, advanced ovarian cancer. In this article, we discuss currently existing options for the treatment of ascites associated with ovarian cancer, and review the literature as it pertains to novel, targeted therapies. Specifically, preclinical and clinical trials exploring the use of the antiangiogenic agents, bevacizumab and vascular endothelial growth factor-trap, as well as the nonangiogenic agent, catumaxomab, will be reviewed. Despite current limitations in treatment, knowledge regarding management options in the palliation of ascites is critical to practicing physicians. Ultimately, as with all novel therapies, symptom relief and treatment goals must be weighed against patient discomfort and potentially significant adverse events.

Monoclonal antibodies in gynecological cancer: a critical point of view

During the last decades, several improvements in treating gynecological malignancies have been achieved. In particular, target therapies, mostly monoclonal antibodies, have emerged as an attractive option for the treatment of these malignancies. In fact, various molecular-targeted agents have been developed for a variety of malignancies with the objective to interfere with a precise tumor associated receptor, essential for cancer cell survival or proliferation, blocking its function, of the cancer cells. Alternatively, monoclonal antibodies have been developed to block immune suppression or enhance functions of immune effector cells. So far, several monoclonal antibodies have been tested for clinical efficacy for the treatment of gynecological cancers. Antibodies against Vascular Endothelial Growth Factor (VEGF) and Epidermal Growth Factor Receptor (EGFR) have been used in different neoplasms such as ovarian and cervical cancer. Catumazumab, a bivalent antibody against CD3 and EpCAM, is effective in the treatment of neoplastic ascites. Other antibodies are peculiar for specific cancer-associated antigen such as Oregovomab against CA125 or Farletuzumab against the folate receptor. Here we describe the preclinical and clinical experience gained up to now with monoclonal antibodies in tumors of the female genital tract and trace future therapeutic and research venues.

Identification of novel neutralizing single-chain antibodies against vascular endothelial growth factor receptor 2

Human vascular endothelial growth factor (VEGF) and its receptor (VEGFR-2/kinase domain receptor [KDR]) play a crucial role in angiogenesis, which makes the VEGFR-2 signaling pathway a major target for therapeutic applications. In this study, a single-chain antibody phage display library was constructed from spleen cells of mice immunized with recombinant human soluble extracellular VEGFR-2/KDR consisting of all seven extracellular domains (sKDR D1-7) to obtain antibodies that block VEGF binding to VEGFR-2. Two specific single-chain antibodies (KDR1.3 and KDR2.6) that recognized human VEGFR-2 were selected; diversity analysis of the clones was performed by BstNI fingerprinting and nucleotide sequencing. The single-chain variable fragments (scFvs) were expressed in soluble form and specificity of interactions between affinity purified scFvs and VEGFR-2 was confirmed by ELISA. Binding of the recombinant antibodies for VEGFR-2 receptors was investigated by surface plasmon resonance spectroscopy. In vitro cell culture assays showed that KDR1.3 and KDR2.6 scFvs significantly suppressed the mitogenic response of human umbilical vein endothelial cells to recombinant human VEGF(165) in a dose-dependent manner, and reduced VEGF-dependent cell proliferation by 60% and 40%, respectively. In vivo analysis of these recombinant antibodies in a rat cornea angiogenesis model revealed that both antibodies suppressed the development of new corneal vessels (p < 0.05). Overall, in vitro and in vivo results disclose strong interactions of KDR1.3 and KDR2.6 scFvs with VEGFR-2. These findings indicate that KDR1.3 and KDR2.6 scFvs are promising antiangiogenic therapeutic agents.

Bevacizumab plus microtubule targeting agents in heavily pre-treated ovarian cancer patients: a retrospective study

OBJECTIVES. As vascular endothelial growth factor (VEGF) is expressed in ovarian cancer, we assessed the efficacy and safety of bevacizumab (a monoclonal antibody targeting VEGF) plus microtubule targeting agents for heavily pre-treated ovarian carcinoma patients. METHODS. We retrospectively reviewed 43 patients with recurrent epithelial ovarian carcinoma. Combined treatment included bevacizumab with paclitaxel in 32 (74%), docetaxel in 10 (23%), and vinorelbine in one (2.3%) patients, respectively. RESULTS. The median number of combined treatment was six cycles (range 1-29). On RECIST criteria, the objective response rate (ORR) was 40% (16% CR and 24% PR). Clinical benefit (complete response [CR] plus partial response [PR] and stable disease [SD] lasting ≥ 3 months) was 74% (CI95%: 46.7-77%). Median duration of treatment and overall survival were 3.9 months (range 0.2-14.4 months) and 20.1 months (CI95%: 13.8-20.1) respectively. No toxic death was reported. Grade 3-4 toxicity occurred in 30% of patients. Gastrointestinal perforations and fistula occurred in 3 (7%) and 6 (14%) patients, respectively. CONCLUSION. Although being active in terms of ORR, bevacizumab plus microtubule targeting agents - mainly taxanes - leads to a high rate of gastro-intestinal perforations and fistula in heavily pre-treated ovarian carcinoma patients.

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.

HN125: A Novel Immunoadhesin Targeting MUC16 with Potential for Cancer Therapy

Background: The mucin MUC16 expresses the repeating peptide epitope CA125 that has been known for decades to be a well-validated cancer marker that is overexpressed on the cell surface of ovarian cancers and other malignant tumors. In spite of recent efforts to make mouse monoclonal antibodies to MUC16 to treat ovarian cancer, a human monoclonal antibody against this mucin has not been described. MUC16 interacts with mesothelin, a protein that mediates heterotypic cancer cell adhesion, indicating that MUC16 and mesothelin play an important role in the peritoneal implantation and metastasis of ovarian tumors. Therefore, a suitable candidate for therapeutic targeting of MUC16 would functionally block the interaction of MUC16 and mesothelin.

Methodology/Principal Findings: Here we report the generation of a novel immunoadhesin, HN125, against MUC16 that consists of a functional MUC16 binding domain of mesothelin (IAB) and the Fc portion of a human antibody IgG1. The yield for purified HN125 proteins is over 100 µg/mL of HEK-293 culture supernatant. We show that HN125 has high and specific affinity for MUC16-expressing cancer cells by flow cytometry and immunohistochemistry. HN125 has the ability to disrupt the heterotypic cancer cell adhesion mediated by the MUC16-mesothelin interaction. Moreover, it elicits strong antibody-dependent cell mediated cytotoxicity against MUC16-positive cancer cells in vitro.

Conclusion/Significance: This report describes a novel human immunotherapeutic agent highly specific for MUC16 with potential for treating ovarian cancer and other MUC16-expressing tumors. Because of its lower immunogenicity in patients, a fully human protein is the most desirable format for clinical applications. We believe that the methods developed here may apply to the generation of other tumor-targeting immunoadhesins when it is difficult to obtain a human monoclonal antibody to a given antigen for clinical applications. The resultant immunoadhesins can have advantages usually found in monoclonal antibodies such as ease of purification, high binding affinity and effector functions.

Differential effect of intraperitoneal albendazole and paclitaxel on ascites formation and expression of vascular endothelial growth factor in ovarian cancer cell-bearing athymic nude mice

OBJECTIVES

The purposes of our study were to evaluate the effect of intraperitoneal albendazole on tumor growth, ascites formation, and vascular endothelial growth factor (VEGF) mRNA expression, and to assess the synergistic effect of paclitaxel in OVCAR-3-bearing nude mice.

METHODS

In all, 4 groups of mice were injected intraperitoneally with weekly albendazole (450 mg/kg per week), paclitaxel (30 mg/kg per week), albendazole plus paclitaxel, or normal saline for 4 weeks.

RESULTS

Ascitic fluid accumulation (2.47, 2.65, 2.88, and 5.90 mL, respectively) and in ascitic VEGF levels were significantly reduced in the 3 treatment groups compared to the control group (170.83, 229.16, 267, and 1625 pg/mL, respectively). However, complete tumor suppression was more prominent in the paclitaxel group, and VEGF mRNA expression was more strongly inhibited in the albendazole group (P < .05). No synergistic effect of albendazole and paclitaxel was observed.

CONCLUSION

We demonstrated a differential effect of albendazole and paclitaxel in a xenograft model of ovarian carcinoma; albendazole suppressed ascites formation by inhibiting VEGF secretion, and paclitaxel exerted its effects by direct cytotoxicity.

Bevacizumab and its use in epithelial ovarian cancer

Bevacizumab is a monoclonal antibody that binds to VEGF, a circulating protein involved in the promotion of angiogenesis and probably tumor growth and progression. Bevacizumab has demonstrated anticancer activity in several cancers, either combined with chemotherapy or when used as a single agent, and has been approved by the US FDA as a treatment for several cancers. As VEGF has been implicated in ovarian cancer progression and ascites formation, and high levels of VEGF have been found in plasma and ascites in women with ovarian cancer, bevacizumab has been tested as an anticancer therapy in ovarian cancer. Documented single-agent activity of bevacizumab in recurrent ovarian cancer has led to combination studies with both biologic agents as well as other chemotherapy agents in both recurrent and newly diagnosed cancer. One trial in patients with recurrent, heavily pretreated ovarian cancer demonstrated a higher than predicted risk of gastrointestinal perforation, and although a lower incidence of gastrointestinal perforation has been reported in less heavily pretreated patients, patients and their physicians must be aware of this risk. Upfront studies testing the impact of adding bevacizumab to carboplatin and paclitaxel chemotherapy for the treatment of newly diagnosed cancer are currently underway, and one Phase III randomized study (Gynecologic Oncology Group study 218) was recently presented and will be discussed in this article.

Bevacizumab in the treatment of ovarian cancer

Despite advances in surgical cytoreduction and cytotoxic chemotherapy, ovarian cancer continues to be the leading cause of death in women with gynecologic malignancy. Our understanding of the treatment of ovarian cancer was revolutionized with the discovery of platinum- and taxane-based adjuvant chemotherapy regimens. Since that time however, overall survival has been stable. Given the above, an emphasis has been placed on exploring alternative therapeutics. Recent research efforts have improved our understanding of the molecular biology of ovarian cancer and novel targeted treatment strategies have emerged. The most studied of these agents has been the monoclonal anti-vascular endothelial growth factor antibody bevacizumab. The purpose of this review is to discuss management issues related to the treatment of ovarian cancer, with a focus on the utilization of bevacizumab, summarizing applicable clinical trials, its potential benefits, and reported adverse events.

A phase II study of sunitinib in patients with recurrent epithelial ovarian and primary peritoneal carcinoma: an NCIC Clinical Trials Group Study

PURPOSE

Sunitinib is a multitargeted receptor tyrosine kinase inhibitor. We conducted a two-stage phase II study to evaluate the objective response rate of oral sunitinib in recurrent epithelial ovarian cancer.

PATIENTS AND METHODS

Eligibility required measurable disease and one or two prior chemotherapies, at least one platinum based. Platinum-sensitive or -resistant disease was allowed. Initial dose schedule was sunitinib 50 mg daily, 4 of 6 weeks. Observation of fluid accumulations during off-treatment periods resulted in adoption of continuous 37.5 mg daily dosing in the second stage of accrual.

RESULTS

Of 30 eligible patients, most had serous histology (67%), were platinum sensitive (73%) and had two prior chemotherapies (60%). One partial response (3.3%) and three CA125 responses (10%) were observed, all in platinum-sensitive patients using intermittent dosing. Sixteen (53%) had stable disease. Five had >30% decrease in measurable disease. Overall median progression-free survival was 4.1 months. Common adverse events included fatigue, gastrointestinal symptoms, hand-foot syndrome and hypertension. No gastrointestinal perforation occurred.

CONCLUSIONS

Single-agent sunitinib has modest activity in recurrent platinum-sensitive ovarian cancer, but only at the 50 mg intermittent dose schedule, suggesting that dose and schedule may be vital considerations in further evaluation of sunitinib in this cancer setting.

Evidence for the role of bevacizumab in the treatment of advanced metastatic breast cancer: a review

Angiogenesis inhibitors may provide a new approach to the treatment of metastatic breast cancer. Bevacizumab is a monoclonal antibody against pathologic angiogenesis. A pivotal study (ECOG 2100) showed that bevacizumab in combination with paclitaxel increased progression-free survival for patients with metastatic breast cancer by 6 months. Subsequently, several clinical trials have shown that the combination of bevacizumab with a taxane can improve disease-free survival but does not prolong overall survival. While generally well tolerated, bevacizumab is potentially toxic for some patients who develop hypertension, proteinuria, bleeding, impaired wound healing, bowel perforation or thromboembolic events. Here, we review the current evidence for the use of bevacizumab in breast cancer and ongoing studies that address the questions of how to optimize regimens and schedules for the use of anti-angiogenic agents and the identification of those patients who would benefit the most from treatment with regimens that include antiangiogenic therapy.

Potent preclinical impact of metronomic low-dose oral topotecan combined with the antiangiogenic drug pazopanib for the treatment of ovarian cancer

Low-dose metronomic chemotherapy has shown promising activity in many preclinical and some phase II clinical studies involving various tumor types. To evaluate further the potential therapeutic impact of metronomic chemotherapy for ovarian cancer, we developed a preclinical model of advanced human ovarian cancer and tested various low-dose metronomic chemotherapy regimens alone or in concurrent combination with an antiangiogenic drug, pazopanib. Clones of the SKOV-3 human ovarian carcinoma cell line expressing a secretable beta-subunit of human choriogonadotropic (beta-hCG) protein and firefly luciferase were generated and evaluated for growth after orthotopic (i.p.) injection into severe combined immunodeficient mice; a highly aggressive clone, SKOV-3-13, was selected for further study. Mice were treated beginning 10 to 14 days after injection of cells when evidence of carcinomatosis-like disease in the peritoneum was established as assessed by imaging analysis. Chemotherapy drugs tested for initial experiments included oral cyclophosphamide, injected irinotecan or paclitaxel alone or in doublet combinations with cyclophosphamide; the results indicated that metronomic cyclophosphamide had no antitumor activity whereas metronomic irinotecan had potent activity. We therefore tested an oral topoisomerase-1 inhibitor, oral topotecan, at optimal biological dose of 1 mg/kg/d. Metronomic oral topotecan showed excellent antitumor activity, the extent of which was significantly enhanced by concurrent pazopanib, which itself had only modest activity, with 100% survival values of the drug combination after six months of continuous therapy. In conclusion, oral topotecan may be an ideal agent to consider for clinical trial assessment of metronomic chemotherapy for ovarian cancer, especially when combined with an antiangiogenic drug targeting the vascular endothelial growth factor pathway, such as pazopanib. Mol Cancer Ther; 9(4); 996-1006. (c)2010 AACR.

Role of vascular endothelial growth factor inhibitors in the treatment of gynecologic malignancies

This article reviews the history and current status of vascular endothelial growth factor targeted therapy for the most common gynecologic malignancies - epithelial ovarian, endometrial and cervical cancers. The biologic rationale for targeting vascular endothelial growth factor (VEGF) for these disease sites is well-founded, and pre-clinical studies have supported the development of anti-VEGF agents. Their classification, known mechanisms of action, unique toxicities and clinical development are herein explored, the latter including issues related to study design, disease site and disease setting.

Targeted therapies in epithelial ovarian cancer

Epithelial ovarian cancer remains a major women's health problem due to its high lethality. Despite great efforts to develop effective prevention and early detection strategies, most patients are still diagnosed at advanced stages of disease. This pattern of late presentation has resulted in significant challenges in terms of designing effective therapies to achieve long-term cure. One potential promising strategy is the application of targeted therapeutics that exploit a myriad of critical pathways involved in tumorigenesis and metastasis. This review examines three of the most provocative targeted therapies with current or future applicability in epithelial ovarian cancer.

Antivascular therapy for epithelial ovarian cancer

Ovarian cancer is the fifth largest cancer killer in women. Improved understanding of the molecular pathways implicated in the pathogenesis of ovarian cancer has led to the investigation of novel targeted therapies. Ovarian cancer is characterized by an imbalance between pro- and antiangiogenic factors in favor of angiogenesis activation. Various antivascular strategies are currently under investigation in ovarian cancer. They can schematically be divided into antiangiogenic and vascular-disrupting therapies. This paper provides a comprehensive review of these new treatments targeting the tumor vasculature in this disease. Promising activities have been detected in phase II trials, and results of phase III clinical trials are awaited eagerly.

Current status of anti-angiogenic agents in the treatment of ovarian carcinoma

During the last decade we have assisted in the development of new therapeutic strategies for the treatment of ovarian cancer, based on the best knowledge of molecular biology. One of the most promising strategies under investigation is antiangiogenic therapy. Bevacizumab is a monoclonal humanised antibody targeting vascular endothelial growth factor (VEGF), which has shown antitumour activity in ovarian cancer in preclinical models as well as in clinical trials, both in monotherapy and in combination with other therapies. Currently, ongoing phase III trials are testing bevacizumab as a front-line therapy with carboplatin and paclitaxel. Bevacizumab has been generally well tolerated with mild frequent toxicities (proteinuria, hypertension and bleeding). However, the drug may result in other uncommon, but potentially life-threatening side effects, such as arterial thromboembolism, wound healing complications, and gastrointestinal perforation or fistulae, which should be considered when the drug is administered. Other new therapeutic antiangiogenic strategies that include small-molecule tyrosine kinase inhibitors, antibodies neutralising the VEGF receptor (VEGFR) and soluble VEGFR hybrids (VEGF Trap) are being investigated with promising early results.

Antiangiogenic drugs in ovarian cancer

BACKGROUND

There is a critical need to develop effective new strategies for the management of patients with advanced epithelial ovarian cancer.

OBJECTIVE

The purpose of this manuscript is to discuss the rationale for, and initial clinical results of, attempts to interfere with the process of tumor angiogenesis as a novel treatment paradigm in ovarian cancer.

RESULTS/CONCLUSION

Phase II clinical trial data provide strong support for the suggestion that antiangiogenic agents have the potential to play a major therapeutic role in this difficult malignancy. It is reasonable to acknowledge that the pending results of several ongoing evidence-based randomized Phase III trials that directly explore the clinical utility of this strategy may substantially alter the current standard management approaches in advanced ovarian cancer.

Complete remission of ovarian cancer induced intractable malignant ascites with intraperitoneal bevacizumab. Immunological observations and a literature review

Malignant ascites resistant to conventional drugs frequently affects ovarian cancer patients at the end of life. Here we report the case of a patient who benefited from complete resolution of ascites after low dose intraperitoneal administration of bevacizumab. Immunological analyses showed an initial increase in proportion and function of CD8(+) effector T cells and a reduction of circulating T(reg) cells. A review of the current literature regarding bevacizumab in ovarian cancer is reported. Bevacizumab has shown a high efficacy in the treatment of ovarian cancer. Intraperitoneal administration induces an immune activation and appears promising in the treatment of malignant ascites.

Preclinical studies and clinical utilization of monoclonal antibodies in epithelial ovarian cancer

OBJECTIVE

To present an overview of selected monoclonal antibodies (mAbs) that have been studied in epithelial ovarian cancer with a focus on combination treatment with conventional chemotherapy.

METHODS

The authors perform a narrative review of the literature. Preclinical studies that provided rationale for mAb use are examined, and selected clinical trials that evaluated efficacy and tolerability are reviewed.

RESULTS

Numerous mAbs have been utilized in epithelial ovarian cancer, including bevacizumab (anti-vascular endothelial growth factor), trastuzumab (anti-human epidermal growth factor-2), cetuximab (anti-epidermal growth factor receptor), and oregovomab (anti-CA125). Favorable preclinical results have lead to the development of a number of clinical trials. Side-effects have been minimal and combination therapy has been well-tolerated. Efficacy has been variable in the clinical trials.

CONCLUSIONS

Targeted treatment with mAbs in conjunction with cytotoxic chemotherapy has been an important research area during the last decade. This therapeutic approach holds promise for improved outcomes in patients with ovarian cancer.