Effects of bevacizumab and pegylated liposomal doxorubicin for the patients with recurrent or refractory ovarian cancers

Enhanced antitumor and anti-metastasis by VEGFR2-targeted doxorubicin immunoliposome synergy with NK cell activation

Liposomal doxorubicin exhibits stronger drug accumulation at the tumor site due to the Enhanced Permeability and Retention (EPR) effect. However, the prognosis for the patient is poor due to this drug's lack of targeting and tumor metastasis during treatment. Vascular epidermal growth factor receptor (VEGFR2) plays an important role in angiogenesis and cancer metastasis. To enhance antitumor efficacy of PEGylated liposomal doxorubicin, we constructed a VEGFR2-targeted and doxorubicin-loaded immunoliposome (Lipo-DOX-C00) by conjugating a VEGFR2-specific, single chain antibody fragment to DSPE-PEG2000-MAL, and then we inserted the antibody-conjugated polymer into liposomal doxorubicin (Lipo-DOX). The immunoliposome was formed uniformly with high affinity for VEGFR2. In vitro, Lipo-DOX-C00 enhanced doxorubicin internalization into LLC and 4T1 cells compared with non-conjugated, liposomal doxorubicin. In vivo, Lipo-DOX-C00 delivered DOX to tumor tissues effectively, which exhibited an improved antitumor and anti-metastasis efficacy in both LLC subcutaneous tumor models and 4T1 tumor models. In addition, the combined therapy of a VEGFR2-MICA bispecific antibody (JZC01) and Lipo-DOX-C00 achieved enhanced inhibition of cancer growth and metastasis due to activation of the immune system. Our study provides a promising approach to clinical application of liposomal doxorubicin.

Real-world study of bevacizumab treatment in patients with ovarian cancer: a Chinese single-institution study of 155 patients

OBJECTIVE

The purpose of this study was to retrospectively assess the pattern, compliance, efficacy and safety of bevacizumab in Chinese ovarian cancer patients.

METHODS

We reviewed the clinicopathological data of patients with histologically confirmed epithelial ovarian cancer, fallopian tube cancer and primary peritoneal adenocarcinoma, who were diagnosed and treated at the Department of Gynecologic Oncology of Peking University Cancer Hospital between May 2012 and January 2022.

RESULTS

A total of 155 patients were eventually enrolled in this study, with 77 as first-line chemotherapy (FL) and 78 as recurrence therapy (RT) among which 37 patients were platinum sensitive and 41 were platinum resistant. Among the 77 patients in the FL group, 35 received bevacizumab during neoadjuvant chemotherapy (NACT) alone (NT), 23 received bevacizumab during both neoadjuvant and first-line chemotherapy (NT + FL) and 19 received bevacizumab during first-line chemotherapy alone (FLA). Among the 43 patients of NT and NT + FL groups undergoing interval debulking surgery (IDS), 38(88.4%) patients achieved optimally debulking and 24 (55.8%) patients had no residual disease after IDS. The patients in the FL group had a median progression free survival (PFS) of 15(95%CI: 9.951-20.049) months, and the 12-month PFS was 61.7%. In the RT group, the overall response rate (ORR) was 53.8%. According to multivariate analysis, the patients' platinum sensitivity had a significant impact on the PFS in the RT group. 13(8.4%) patients discontinued bevacizumab due to toxicity. Seven patients were in the FL group while 4 patients were in the RT group. The most common adverse event associated with bevacizumab therapy was hypertension.

CONCLUSION

Bevacizumab is effective and well-tolerated in the real world setting of ovarian cancer treatment. Adding bevacizumab to NACT is feasible and tolerable. Receiving the regimen containing bevacizumab in the last preoperative chemotherapy did not result in increased intraoperative bleeding of IDS. Platinum sensitivity is the most important factor affecting the effectiveness of bevacizumab in recurrent patients.

Targeted Anti-Mitochondrial Therapy: The Future of Oncology

Like living organisms, cancer cells require energy to survive and interact with their environment. Mitochondria are the main organelles for energy production and cellular metabolism. Recently, investigators demonstrated that cancer cells can hijack mitochondria from immune cells. This behavior sheds light on a pivotal piece in the cancer puzzle, the dependence on the normal cells. This article illustrates the benefits of new functional mitochondria for cancer cells that urge them to hijack mitochondria. It describes how functional mitochondria help cancer cells’ survival in the harsh tumor microenvironment, immune evasion, progression, and treatment resistance. Recent evidence has put forward the pivotal role of mitochondria in the metabolism of cancer stem cells (CSCs), the tumor components responsible for cancer recurrence and metastasis. This theory highlights the mitochondria in cancer biology and explains how targeting mitochondria may improve oncological outcomes.

Orchestrated Action of AMPK Activation and Combined VEGF/PD-1 Blockade with Lipid Metabolic Tunning as Multi-Target Therapeutics against Ovarian Cancers

Ovarian cancer is one of the most lethal gynecological malignancies worldwide, and chemoresistance is a critical obstacle in the clinical management of the disease. Recent studies have suggested that exploiting cancer cell metabolism by applying AMP-activated protein kinase (AMPK)-activating agents and distinctive adjuvant targeted therapies can be a plausible alternative approach in cancer treatment. Therefore, the perspectives about the combination of AMPK activators together with VEGF/PD-1 blockade as a dual-targeted therapy against ovarian cancer were discussed herein. Additionally, ferroptosis, a non-apoptotic regulated cell death triggered by the availability of redox-active iron, have been proposed to be governed by multiple layers of metabolic signalings and can be synergized with immunotherapies. To this end, ferroptosis initiating therapies (FITs) and metabolic rewiring and immunotherapeutic approaches may have substantial clinical potential in combating ovarian cancer development and progression. It is hoped that the viewpoints deliberated in this review would accelerate the translation of remedial concepts into clinical trials and improve the effectiveness of ovarian cancer treatment.

Metastatic Ovarian Cancer Presenting as Inflammatory Breast Cancer: A Case Report

Metastatic ovarian cancer to the breast is a rare presentation, with limited cases reported worldwide. Common sites for distant metastasis in ovarian cancer are to the liver, lung, and pleura [Dauplat et al. Cancer. 1987 Oct 1;60(7):1561-6]. Usually, such cases predict poor prognosis with troublesome management. We present one challenging case of a 54-year-old female patient with recurrent clear cell ovarian cancer, presenting with right breast mass of primary versus secondary origin, progressing into inflammatory breast cancer picture. Our report aims to shed light on the value of early suspicion and low threshold of detecting secondary breast masses of ovarian cancer origin.

Bevacizumab use in the frontline, maintenance and recurrent settings for ovarian cancer

On 13 June 2018, Genentech, Inc. issued a press release announcing that the US FDA had approved the antiangiogenesis drug, bevacizumab, in combination with chemotherapy for frontline and maintenance therapy for women with newly diagnosed ovarian cancer. Regulatory approval was based on the National Cancer Institute-sponsored Gynecologic Oncology Group (GOG) protocol 0218, the Phase III, randomized, placebo-controlled, double-blind, multi-center and multi-national clinical trial that met its primary end point, progression-free survival. Bevacizumab is now approved in the frontline, platinum-sensitive recurrent and platinum-resistant recurrent settings for epithelial ovarian cancer. This review will address the broad range of clinical trials addressing the efficacy of bevacizumab use in ovarian cancer.

Comparison of clinico-pathological characteristics and survival of recurrent ovarian cancer patients on seven different chemo-protocols

Despite growing prevalence of ovarian cancer (OC) in Pakistan, no literature evidence exists regarding its clinic-pathological characteristics, survival and compliance of patients with recurrent ovarian cancer on various chemo-protocols. An observational study was conducted by enrolling 251 recurrent OC patients on 7 different chemo-protocols, from a specialized cancer care hospital, Lahore, Pakistan, using convenient judgmental sampling. The study was conducted for a period of 6 months. Most of the patients were between 18 and 70 years of age, with IIIC FIGO stage and papillary serous histological grade. As per RECIST, improved partial response (PR) (63.3 %) and complete response (CR) (52.1 %) was observed in the CP (carboplatin + paclitaxel) arm, substantiated by improved median progression free survival (PFS) and overall survival (OS) in CP and CD (carboplatin + docetaxel) arms, respectively, yet with no significant differences in survival curves, PFS (p = 0.12) and OS (p = 0.22). Interestingly, the highest and the lowest patient non-compliance were observed in CG (carboplatin + gemcitabine) (81.6 %) and paclitaxel (4.5 %) arms, resp. As per the hazard model for survival, topotecan showed significant association with the therapy related events/deaths compared to other protocols. These data suggest that CP regimen exhibited improved clinical efficacy and decreased toxicity related non-compliance in recurrent ovarian cancer patients of Lahore.

A phase II study of apatinib in patients with recurrent epithelial ovarian cancer

OBJECTIVE

Antiangiogenic treatments have been implicated to play a major role in epithelial ovarian cancer (EOC). Apatinib, a novel oral antiangiogenic agent targeting vascular endothelial growth factor receptor (VEGFR2), is currently being studied in different tumor types and is already used in gastric adenocarcinoma. This study was performed to assess the efficacy and safety of apatinib in patients with recurrent, pretreated EOC.

PATIENTS AND METHODS

Patients with recurrent, platinum-resistant, pre-treated EOC who failed available standard chemotherapy were enrolled. Apatinib was administered as 500mg daily. Primary objective is the overall response rate (ORR) according to MASS criteria. Secondary objectives are progression free survival (PFS), overall survival (OS), disease control rate (DCR), safety and tolerability. The treatment duration is until disease progression or intolerability of apatinib.

RESULTS

29 eligible patients were enrolled in this multicenter, open-label, single arm study and received apatinib for a median of 36.8weeks (range 13-64.8weeks). Median follow-up time was 12months. 28 patients were eligible for efficacy analysis. ORR is 41.4% (95% confidence interval (CI), 23.3%-59.4%). DCR is 68.9% (95% CI, 52.1%-85.8%). Median PFS is 5.1months (95% CI, 3.8m-6.5m). Median OS is 14.5months (95% CI, 12.4m-16.4m). The most common treatment-related adverse events (AEs) were hand-foot syndrome (51.7%), hypertension (34.6%), nausea and vomiting (31.0%). 3 patients had no significant toxicity. 9 patients experienced grade 3 treatment-related AEs.

CONCLUSIONS

Apatinib 500mg daily p.o. is a feasible treatment in patients with recurrent, platinum-resistant, pretreated EOC. Multi-center prospective studies enrolling more patients are needed.

Use of short interfering RNA delivered by cationic liposomes to enable efficient down-regulation of PTPN22 gene in human T lymphocytes

Type 1 diabetes and thyroid disease are T cell-dependent autoimmune endocrinopathies. The standard substitutive administration of the deficient hormones does not halt the autoimmune process; therefore, development of immunotherapies aiming to preserve the residual hormonal cells, is of crucial importance. PTPN22 C1858T mutation encoding for the R620W lymphoid tyrosine phosphatase variant, plays a potential pathophysiological role in autoimmunity. The PTPN22 encoded protein Lyp is a negative regulator of T cell antigen receptor signaling; R620W variant, leading to a gain of function with paradoxical reduced T cell activation, may represent a valid therapeutic target. We aimed to develop novel wild type PTPN22 short interfering RNA duplexes (siRNA) and optimize their delivery into Jurkat T cells and PBMC by using liposomal carriers. Conformational stability, size and polydispersion of siRNA in lipoplexes was measured by CD spectroscopy and DLS. Lipoplexes internalization and toxicity evaluation was assessed by confocal microscopy and flow cytometry analysis. Their effect on Lyp expression was evaluated by means of Western Blot and confocal microscopy. Functional assays through engagement of TCR signaling were established to evaluate biological consequences of down-modulation. Both Jurkat T cells and PBMC were efficiently transfected by stable custom lipoplexes. Jurkat T cell morphology and proliferation was not affected. Lipoplexes incorporation was visualized in CD3+ but also in CD3- peripheral blood immunotypes without signs of toxicity, damage or apoptosis. Efficacy in affecting Lyp protein expression was demonstrated in both transfected Jurkat T cells and PBMC. Moreover, impairment of Lyp inhibitory activity was revealed by increase of IL-2 secretion in culture supernatants of PBMC following anti-CD3/CD28 T cell receptor-driven stimulation. The results of our study open the pathway to future trials for the treatment of autoimmune diseases based on the selective inhibition of variant PTPN22 allele using lipoplexes of siRNA antisense oligomers.

Targeted multidrug delivery system to overcome chemoresistance in breast cancer

Chemotherapy has been widely used in breast cancer patients to reduce tumor size. However, most anticancer agents cannot differentiate between cancerous and normal cells, resulting in severe systemic toxicity. In addition, acquired drug resistance during the chemotherapy treatment further decreases treatment efficacy. With the proper treatment strategy, nanodrug carriers, such as liposomes/immunoliposomes, may be able to reduce undesired side effects of chemotherapy, to overcome the acquired multidrug resistance, and to further improve the treatment efficacy. In this study, a novel combinational targeted drug delivery system was developed by encapsulating antiangiogenesis drug bevacizumab into liposomes and encapsulating chemotherapy drug doxorubicin (DOX) into immunoliposomes where the human epidermal growth factor receptor 2 (HER2) antibody was used as a targeting ligand. This novel combinational system was tested in vitro using a HER2 positive and multidrug resistant breast cancer cell line (BT-474/MDR), and in vivo using a xenograft mouse tumor model. In vitro cell culture experiments show that immunoliposome delivery led to a high cell nucleus accumulation of DOX, whereas free DOX was observed mostly near the cell membrane and in cytoplasm due to the action of P-gp. Combining liposomal bevacizumab with immunoliposomal DOX achieved the best tumor growth inhibition and the lowest toxicity. Tumor size decreased steadily within a 60-day observation period indicating a potential synergistic effect between DOX and bevacizumab through the targeted delivery. Our findings clearly indicate that tumor growth was significantly delayed in the combinational liposomal drug delivery group. This novel combinational therapy has great potential for the treatment of patients with HER2/MDR double positive breast cancer.

Profile of bevacizumab in the treatment of platinum-resistant ovarian cancer: current perspectives

Patients with platinum-resistant ovarian cancer have progression of disease within 6 months of completing platinum-based chemotherapy. While several chemotherapeutic options exist for the treatment of platinum-resistant ovarian cancer, the overall response to any of these therapies is ~10%, with a median progression-free survival of 3–4 months and a median overall survival of 9–12 months. Bevacizumab (Avastin), a humanized, monoclonal antivascular endothelial growth factor antibody, has demonstrated antitumor activity in the platinum-resistant setting and was recently approved by US Food and Drug Administration for combination therapy with weekly paclitaxel, pegylated liposomal doxorubicin, or topotecan. This review summarizes key clinical trials investigating bevacizumab for recurrent, platinum-resistant ovarian cancer and provides an overview of efficacy, safety, and quality of life data relevant in this setting. While bevacizumab is currently the most studied and clinically available antiangiogenic therapy, we summarize recent studies highlighting novel alternatives, including vascular endothelial growth factor-trap, tyrosine kinase inhibitors, and angiopoietin inhibitor trebananib, and discuss their application for the treatment of platinum-resistant ovarian cancer.

Emerging therapies: angiogenesis inhibitors for ovarian cancer

INTRODUCTION

Patients with epithelial ovarian cancer (EOC) have a high rate of recurrence, and overall survival remains at ∼ 25%. There is a need for new treatments that can increase progression free survival and quality of life. Recent clinical trials focus on angiogenesis, VEGFs, and tyrosine kinase inhibitors that play a role in recurrence, metastasis, and ascites in EOC.

AREAS COVERED

This review summarizes clinical rationale, mechanisms of action, and clinical data for angiogenesis inhibitors under evaluation in Phase II and III trials for EOC. Anti-angiogenesis agents reviewed in this paper include aflibercept, bevacizumab, cediranib, fosbretabulin, imatinib, nintedanib, pazopanib, saracatinib, sorafenib, sunitinib, and trebananib.

EXPERT OPINION

These agents have particular rationale for potential use in EOC due to the molecular changes associated with EOC tumorigenesis, namely a significant increase in angiogenic activity. Due to the costs and toxicities associated with anti-angiogenics, biomarker or molecular signature selection strategy for patients who will most benefit would be ideal but no such strategy has been validated to date.

Histone deacetylases as new therapy targets for platinum-resistant epithelial ovarian cancer

Introduction

In developed countries, ovarian cancer is the fourth most common cancer in women. Due to the non-specific symptomatology associated with the disease many patients with ovarian cancer are diagnosed late, which leads to significantly poorer prognosis. Apart from surgery and radiotherapy, a substantial number of ovarian cancer patients will undergo chemotherapy and platinum based agents are the mainstream first-line therapy for this disease. Despite the initial efficacy of these therapies, many women relapse; therefore, strategies for second-line therapies are required. Regulation of DNA transcription is crucial for tumour progression, metastasis and chemoresistance which offers potential for novel drug targets.

Methods

We have reviewed the existing literature on the role of histone deacetylases, nuclear enzymes regulating gene transcription.

Results and conclusion

Analysis of available data suggests that a signifant proportion of drug resistance stems from abberant gene expression, therefore HDAC inhibitors are amongst the most promising therapeutic targets for cancer treatment. Together with genetic testing, they may have a potential to serve as base for patient-adapted therapies.

Comparison of bevacizumab alone or with chemotherapy in recurrent ovarian cancer patients

BACKGROUND

To compare the efficacy of chemotherapy (C) combined with bevacizumab (Bev) versus Bev alone in recurrent, heavily pretreated epithelial ovarian cancer (EOC).

METHODS

A multicenter analysis of patients treated from 2004 to 2011 was performed. Demographic, treatment, response, and adverse event information were obtained. Progression-free (PFS) and overall survival (OS) were analyzed.

RESULTS

Of 277 patients (median age: 58years), the majority had Stage III and IV (86%) disease, and 72% had serous histology. 244 (88%) were treated with C+Bev and 33 (12%) with Bev. Corresponding median progression-free survival (PFS) was 8.7 and 6.7months, and median overall survival (OS) was 14.3 and 10.5months, respectively. The chemotherapeutic agents combined with Bev and the median OS include: pegylated liposomal doxorubicin (n=19, OS of 20.4months), taxanes (n=55, OS of 20.2months), gemcitabine (n=106, OS of 14.1months), topotecan (n=43, OS of 13months), and cyclophosphamide (n=21, OS of 13months). There was no significant difference in toxicities between the C+Bev vs. Bev alone group.

CONCLUSION

This retrospective analysis supports that combination chemotherapy and bevacizumab prolongs PFS and OS compared with bevacizumab alone.

The use of ultrasound to release chemotherapeutic drugs from micelles and liposomes

Several drug delivery systems have been investigated to reduce the side effects of chemotherapy by encapsulating the therapeutic agent in a nanosized carrier until it reaches the tumor site. Many of these particles are designed to be responsive to the mechanical and thermal perturbations delivered by ultrasound. Once the nanoparticle reaches the desired location, ultrasound is applied to release the chemotherapy drug only in the vicinity of the targeted (cancer) site, thus avoiding any detrimental interaction with healthy cells in the body. Studies using liposomes and micelles have shown promising results in this area, as these nanoparticles with simple, yet effective structures, showed high efficiency as drug delivery vehicles both in vitro and in vivo. This article reviews the design and application of two novel nanosized chemotherapeutic carriers (i.e. micelles and liposomes) intended to be actuated by ultrasound.

The emerging role of anti-angiogenic therapy in ovarian cancer (review)

The introduction of new therapeutic agents into clinical practice of ovarian cancer, in addition to the role of surgery and chemotherapy, has been the subject of numerous studies because this tumor remains worldwide the most lethal gynecological cancer. It is now known that angiogenesis plays a vital role for ovarian physiology, but also in ovarian carcinogenesis and so it has become the main target of ovarian cancer treatment. In this review, the most common molecular pathways of angiogenesis have been investigated leading to the identification of novel targets, including monoclonal antibodies and tyrosine kinase inhibitors. The fundamental targets of anti-angiogenic drugs are vascular endothelial growth factor receptor and its ligand, but also platelet-derived growth factor, fibroblast growth factor and angiopoietin. Moreover, improved knowledge of angiogenic process allowed the discovery of other molecules, such as semaphorins, neuropilins, clusterin, some transcriptional factors, and the identification of features, including stemness, epithelial-mesenchymal transition, downregulation of certain microRNAs, the alteration of immune system, that contribute to angiogenesis and possibly to resistance mechanisms. The following patent and literature review aim to highlight recent findings of approved and novel anti-angiogenic drugs that make the treatment of patients with ovarian cancer a rapidly growing field of oncology.

Angiogenesis-related pathways in the pathogenesis of ovarian cancer

Ovarian Cancer represents the most fatal type of gynecological malignancies. A number of processes are involved in the pathogenesis of ovarian cancer, especially within the tumor microenvironment. Angiogenesis represents a hallmark phenomenon in cancer, and it is responsible for tumor spread and metastasis in ovarian cancer, among other tumor types, as it leads to new blood vessel formation. In recent years angiogenesis has been given considerable attention in order to identify targets for developing effective anti-tumor therapies. Growth factors have been identified to play key roles in driving angiogenesis and, thus, the formation of new blood vessels that assist in "feeding" cancer. Such molecules include the vascular endothelial growth factor (VEGF), the platelet derived growth factor (PDGF), the fibroblast growth factor (FGF), and the angiopoietin/Tie2 receptor complex. These proteins are key players in complex molecular pathways within the tumor cell and they have been in the spotlight of the development of anti-angiogenic molecules that may act as stand-alone therapeutics, or in concert with standard treatment regimes such as chemotherapy. The pathways involved in angiogenesis and molecules that have been developed in order to combat angiogenesis are described in this paper.

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.

Bevacizumab and ovarian cancer

Bevacizumab is a recombinant humanized monoclonal IgG1 antibody that targets vascular endothelial growth factor-A, and is indicated in the treatment of various tumors (colon, lung, renal, and glioblastoma). It has been recently approved for the treatment of ovarian cancer in various countries. This review summarizes the activity and toxicity of bevacizumab in the treatment of ovarian cancer, both as single-agent drug and in combination with cytotoxic chemotherapy. As a single-agent drug, it has shown response rates of 16-21% in the treatment of recurrent ovarian cancer. Two phase III randomized trials have been published evaluating the addition of bevacizumab to standard chemotherapy as front-line treatment of advanced ovarian cancer. In addition, trials evaluating the combination with chemotherapy in recurrent ovarian cancer (platinum-sensitive and platinum-resistant disease) have also been reported. All these trials showed a statistically significant improvement in progression-free survival although no improvement in overall survival has been reported. The main adverse event is hypertension. Other serious, but uncommon adverse events include gastrointestinal perforation as well as renal and central nervous system toxicity.

Monoclonal antibodies therapies for ovarian cancer

INTRODUCTION

Despite aggressive debulking surgery, intraperitoneal therapies and the use of new drugs for chemotherapy, patients with ovarian cancer (OC) still have poor prognosis and, therefore, new strategies for its management are needed. Molecular-targeted agents can be considered a new option in drug research. Several antigens related to OC have been isolated and they could be potential target of monoclonal antibodies (mAbs); therefore, different mAbs have been developed and are emerging as new potential OC treatments.

AREAS COVERED

This article aims to review the literature on the use of mAbs in the treatment of OC. The purposes of this manuscript are to offer a brief explanation of the mechanisms of action of mAbs and to help readers in understanding the current role of mAbs in the treatment of OC.

EXPERT OPINION

A deeper knowledge of the molecular biology of OC has brought new developments in targeted therapies. Among these therapies, bevacizumab demonstrated the higher clinical efficacy. Further larger trials are needed to better define the role of the other mAbs in OC treatment. There is a strong need to identify and validate robust biomarkers for a more focused patient selection and for tailoring therapies, optimizing dose and assessing response.

Investigational agents in development for the treatment of ovarian cancer

Although significant success has been achieved in the treatment of advanced and recurrent ovarian cancer, there is clearly room for improvement. The use of targeted agents in this patient population has the promise to provide improved survival and quality of life. There are a myriad of relevant pathways under exploration in all settings of ovarian cancer. Clinical trial data are accumulating for antiangiogenic therapy, including vascular endothelial growth factor (VEGF)-specific inhibitors and multiple angiogenic signaling target inhibitors, as well as poly-ADP-ribose polymerase (PARP) inhibitors. Other types of tumorigenic pathway inhibitors, including those that target phosphatidylinositol-3-kinase (PI3K), mammalian target of rapamycin (mTOR), protein kinase B (AKT), Src, folate receptor alpha, and insulin-like growth factor-1 receptor (IGF-1R) pathways are in earlier phases of development for ovarian cancer. Attempts to target the epidermal growth factor receptor (EGFR) of ovarian tumors have been met with limited success; however, newer agents that inhibit this pathway show promise. Finally, with recognition of the role of Wee-1 in p53-deficient tumors, an inhibitor of this tyrosine kinase is being evaluated in recurrent ovarian cancer. The logistical challenge is to determine the optimal timing and proper combinations of novel agents independently as well as concomitantly with conventional chemotherapeutics. Reported results have been modest; however, our growing understanding of these pathways will be potentially reflected in greater impact on response and survival.

The putative role of the C1858T polymorphism of protein tyrosine phosphatase PTPN22 gene in autoimmunity

Autoimmune diseases represent a heterogeneous group of conditions whose incidence is increasing worldwide. This has stimulated studies on their etiopathogenesis, derived from a complex interaction between genetic and environmental factors, in order to improve prevention and treatment of these diseases. An increasing amount of epidemiologic investigations has associated the presence of the C1858T polymorphism in the protein tyrosine phosphatase non-receptor type 22 (PTPN22) gene to the onset of several autoimmune diseases including insulin-dependent diabetes mellitus (Type 1 diabetes). PTPN22 encodes for the lymphoid tyrosine phosphatase Lyp. This belongs to non-receptor-type protein tyrosine phosphatases involved in lymphocyte activation and differentiation. In humans, Lyp may have a role in the negative regulation of T cell receptor signaling. The single nucleotide polymorphism C1858T encodes for a more active phosphatase Lyp R620W. This has the ability to induce a higher negative regulation of T cell receptor signaling. Thus, C1858T could play an important role at the level of thymocyte polarization and escape of autoreactive T lymphocytes, through the positive selection of otherwise negatively selected autoimmune T cells. In this review we discuss the physiological role exerted by the PTPN22 gene and its encoded Lyp product in lymphocyte processes. We highlight the pathogenic significance of the C1858T PTPN22 polymorphism in human autoimmunity with special reference to Type 1 diabetes. Recently the genetic variation in PTPN22 was shown to induce altered function of T and B-lymphocytes. In particular BCR signaling defects and alterations in the B cell compartment were reported in T1D patients. We finally speculate on the possible development of novel therapeutic treatments in human autoimmunity aiming to selectively target the variant Lyp protein in autoreactive T and B lymphocytes.

Phase II study of bevacizumab with liposomal doxorubicin for patients with platinum- and taxane-resistant ovarian cancer

BACKGROUND

Suppression of neoangiogenesis and pegylated liposomal doxorubicin (PLD) each contribute to the management of platinum-resistant/refractory ovarian cancer. The aim of this study is to test the combination of bevacizumab and PLD in women with resistant or refractory ovarian cancer.

METHODS

Eligibility criteria were no more than two prior treatments with platinum-containing regimens and one additional regimen, without anthracyclines. Treatment was administered every 3 weeks (bevacizumab 15 mg/kg beginning on cycle 2 and PLD 30 mg/m(2)). The primary end point was progression-free survival (PFS) at 6 months; the secondary end points included side-effects, overall response rates (ORR) and survival (OS).

RESULTS

Forty-six patients were enrolled. The average number of courses administered was 7. The median PFS was 6.6 months (range 1-24.6 months) according to Gynecologic Cancer Intergroup Committee (GCIC) criteria and 7.8 months (range 2-13.3 months) according to Response Evaluation Criteria in Solid Tumors (RECIST). The median OS was 33.2 months (range 3-37.5+ months). The ORR was 30.2% [95% confidence interval (CI) 17.2-46.1] and the clinical benefit rate (CBR) was 86.1% (95% CI 72.1-94.7). Adverse events included mucosal and dermal erosions (30% grade 3) and asymptomatic cardiac dysfunction. Additional toxic effects included hypertension, headache, renal dysfunction and proteinuria, wound healing delay, and one episode each of central nervous system (CNS) ischemia and hemolytic uremic syndrome.

CONCLUSION

PLD with bevacizumab has improved activity in recurrent ovarian cancer with increased toxicity.

Antiangiogenic agents as a maintenance strategy for advanced epithelial ovarian cancer

Bevacizumab is the first antiangiogenic agent to have demonstrated benefit as first-line and maintenance therapy in epithelial ovarian cancer (EOC), with the Gynecologic Oncology Group 218 and ICON 7 phase III trials revealing significantly prolonged progression-free survival (PFS) for carboplatin/paclitaxel plus bevacizumab followed by bevacizumab maintenance versus carboplatin/paclitaxel alone. Results are forthcoming from several phase III maintenance trials of investigational antiangiogenic agents, each evaluating PFS as the primary endpoint: AGO-OVAR12/LUME-Ovar1 (nintedanib [BIBF 1120]), AGO-OVAR16 (pazopanib), and TRINOVA-1, -2, and -3 (AMG 386). Here we review available data and ongoing clinical trials of investigational antiangiogenic agents as maintenance therapy for EOC. Current controversies, including uncertainties regarding the (1) most appropriate clinical trial endpoints, (2) optimal dosing, duration, and timing of therapy (e.g., with first-line chemotherapy and/or as maintenance monotherapy), and (3) feasibility, tolerability, and cost of adding these agents to platinum/taxane regimens are also highlighted.

Bevacizumab in the treatment of ovarian cancer

INTRODUCTION

In the past decade there have been many attempts to improve systemic treatment and thus the outcome of patients with ovarian cancer. However, neither the sequential addition of non cross-resistant drugs to standard chemotherapy comprising carboplatin and paclitaxel, nor triplet combination therapies with conventional chemotherapeutic drugs have improved outcomes. Instead, such approaches have led to an increase in the incidence of side effects. We are currently experiencing a shift toward the addition of molecularly targeted and biological anticancer therapies to standard treatment. Vascular endothelial growth factor (VEGF), which improves vitally important tumor vasculature, is secreted by a range of tumors, and a high level of VEGF is known to be an independent risk factor for aggressive disease in ovarian cancer. This finding led to the development in the 1990s of bevacizumab, a humanized monoclonal antibody against VEGF.

DISCUSSION

Several phase II trials and four phase III trials have demonstrated that bevacizumab is active in patients with advanced and recurrent ovarian cancer. Both phase III trials of bevacizumab as first-line therapy in advanced ovarian cancer (ICON 7/AGOOVAR 11 and GOG-0218) have shown that the addition of bevacizumab to chemotherapy and as maintenance therapy improves progressionfree survival (PFS). The phase III trials in platinum-sensitive (OCEANS) and platinumresistant, relapsed disease (AURELIA) have also demonstrated a benefit for bevazicumab with respect to PFS. The administration of bevacizumab to improve survival in patients with ovarian cancer is not without side effects and a broad discussion on the cost-effectiveness of this approach is ongoing.

CONCLUSION

This article presents clinical trial data on bevacizumab in the treatment of ovarian cancer and discusses the indication and pitfalls in the application of bevacizumab in patients with this malignancy.

Phase I study of the antiangiogenic antibody bevacizumab and the mTOR/hypoxia-inducible factor inhibitor temsirolimus combined with liposomal doxorubicin: tolerance and biological activity

PURPOSE

Preclinical data suggest that combining the mTOR/hypoxia-inducible factor (HIF) inhibitor temsirolimus and the antiangiogenesis antibody bevacizumab may augment antitumor activity as well as resensitize cells to anthracyclines.

EXPERIMENTAL DESIGN

We initiated a phase I study of bevacizumab and temsirolimus plus liposomal doxorubicin in patients with advanced malignancies. Patients (N = 136) were enrolled according to a modified 3 + 3 design plus dose expansion in responsive tumor types.

RESULTS

The most common cancers were breast (n = 29), epithelial ovarian (n = 23), and colorectal cancer (n = 17). The median number of prior chemotherapy regimens was four (range: 0-16). Grade 3 or higher adverse events (> 5%) included pancytopenia, mucositis, hand-foot syndrome, hypertension, and fistula. This regimen led to a 21% (n = 28) stable disease (SD) ≥ 6 months and 21% (n = 29) rate of partial or complete remission [PR/CR; (total SD ≥ 6 months/PR/CR = 42% (n = 57)]. PR/CR was most common in parotid gland adenocarcinoma (4/6, 67%), metaplastic breast cancer (5/12, 42%), endometrial endometrioid carcinoma (6/15, 40%), and in patients with a PIK3CA mutation and/or a PTEN mutation/loss (11/28, 39%). The maximum tolerated dose was liposomal doxorubicin 30 mg/m(2) and bevacizumab 15 mg/kg every three weeks with temsirolimus 25 mg weekly.

CONCLUSIONS

Patients tolerated bevacizumab and temsirolimus together with liposomal doxorubicin. Further evaluation, especially in patients with parotid, metaplastic breast, and endometrial endometrioid cancer, and in patients with PIK3CA and/or PTEN aberrations is warranted.

Withaferin A synergizes the therapeutic effect of doxorubicin through ROS-mediated autophagy in ovarian cancer

Application of doxorubicin (Dox) for the treatment of cancer is restricted due to its severe side effects. We used combination strategy by combining doxorubicin (Dox) with withaferin A (WFA) to minimize the ill effects of Dox. Treatment of various epithelial ovarian cancer cell lines (A2780, A2780/CP70 and CaOV3) with combination of WFA and Dox (WFA/DOX) showed a time- and dose-dependent synergistic effect on inhibition of cell proliferation and induction of cell death, thus reducing the dosage requirement of Dox. Combination treatment resulted in a significant enhancement of ROS production resulting in immense DNA damage, induction of autophagy analyzed by transmission electron microscope and increase in expression of autophagy marker LC3B, and culminated in cell death analyzed by cleaved caspase 3. We validated combination therapy on tumor growth using an in vitro 3Dimension (3D) tumor model and the more classic in vivo xenograft model of ovarian cancer. Both tumor models showed a 70 to 80% reduction in tumor growth compared to control or animals treated with WFA or Dox alone. Immunohistochemical analysis of the tumor tissues from animals treated with WFA/Dox combination showed a significant reduction in cell proliferation and formation of microvessels accompanied by increased in LC3B level, cleaved caspase 3, and DNA damage. Taken together, our data suggest that combining WFA with Dox decreases the dosage requirement of Dox, therefore, minimizing/eliminating the severe side effects associated with high doses of DOX, suggesting the application of this combination strategy for the treatment of ovarian and other cancers with no or minimum side effects.

Antiangiogenic agents in combination with chemotherapy for the treatment of epithelial ovarian cancer

OBJECTIVE

The purpose of this review was to provide an overview of angiogenesis, including the rationale for targeting angiogenesis as a treatment strategy for epithelial ovarian cancer (EOC) and to discuss available clinical trial data with antiangiogenic agents in EOC, with a focus on combinations with chemotherapy.

METHODS

This was a literature review of clinical studies evaluating select antiangiogenic agents in combination with traditional cytotoxic chemotherapy for the treatment of EOC.

RESULTS

Several therapies that target angiogenesis-specific pathways are undergoing clinical development for EOC. Although some of these agents have demonstrated single-agent activity for EOC, there is considerable interest in combining this treatment strategy with chemotherapy in an effort to potentially improve treatment benefits in this patient population. Bevacizumab, an anti-vascular endothelial growth factor (VEGF) monoclonal antibody, is the most studied antiangiogenic agent in EOC and has shown efficacy as monotherapy and combined with chemotherapy in both the relapsed/recurrent and first-line settings. However, results from recent phase 3 trials raise questions regarding patient selection and optimal dose, schedule, and duration of bevacizumab therapy. Other agents in various phases of testing include aflibercept (VEGF Trap), a fusion protein that binds all isoforms of VEGF; multitargeted antiangiogenic tyrosine kinase inhibitors (eg, BIBF 1120, cediranib, pazopanib, sorafenib); and AMG 386, a selective angiopoietin inhibitor. Toxicities associated with VEGF inhibition are also a concern with antiangiogenic therapy, including hypertension, proteinuria, thromboses, and gastrointestinal perforation.

CONCLUSIONS

Results from recently completed and ongoing clinical trials combining antiangiogenic agents with chemotherapy are awaited in hopes of expanding therapeutic options for patients with EOC.

A case series of low dose bevacizumab and chemotherapy in heavily pretreated patients with epithelial ovarian cancer

BACKGROUND

The addition of bevacizumab to standard chemotherapy prolongs progression free survival in the first line treatment of epithelial ovarian cancer (EOC), but its cost/effectiveness is debated. We assessed the safety and activity of a lower dose of bevacizumab in pretreated advanced stage EOC.

METHODS

We treated 15 patients, mostly with platinum resistant EOC, who had received a median of four prior cytotoxic regimens, with bevacizumab 5-7.5 mg/kg q21 days in combination with either carboplatin (n = 8), oral cyclofosfamide (n = 5) or weekly paclitaxel (n = 2). Bevacizumab was administered until disease progression. Tumor response was assessed by CA125 and fusion 18 F-FDG PET/contrast enhanced CT.

RESULTS

The median number of bevacizumab cycles was 21 (range 3-59). The median baseline CA125 was 272 U/ml and decreased to 15.2 U/ml at nadir. Tumor response was 4 complete response (CR) (26.7%) and 7 partial response (PR) (46.7%) by chemotherapy (CT), with an overall response rate of 73.4% (95% CI, 51.0 - 95.8) according to Response Evaluation Criteria In Solid Tumors (RECIST), and 6 CR (40%) and 4 PR (26.7%) by PET, for an overall metabolic response rate of 67% (95%CI, 42.8 - 90.6) according to PET Response Criteria in Solid Tumors (PERCIST). Median progression free survival (PFS) was 21 months and median overall survival (OS) was 24 months. Grade 3 adverse events related to bevacizumab were hypertension (n = 2), proteinuria (n = 1) and epistaxis (n = 5). Treatment was delayed in five patients for nasal bleeding or uncontrolled hypertension.

CONCLUSIONS

Low-dose bevacizumab and chemotherapy was well tolerated and active in a heavily pretreated population of advanced EOC. Further studies should assess the activity of low dose bevacizumab in EOC.

Significance of vascular endothelial growth factor in growth and peritoneal dissemination of ovarian cancer

Vascular endothelial growth factor (VEGF) is a key regulator of angiogenesis which drives endothelial cell survival, proliferation, and migration while increasing vascular permeability. Playing an important role in the physiology of normal ovaries, VEGF has also been implicated in the pathogenesis of ovarian cancer. Essentially by promoting tumor angiogenesis and enhancing vascular permeability, VEGF contributes to the development of peritoneal carcinomatosis associated with malignant ascites formation, the characteristic feature of advanced ovarian cancer at diagnosis. In both experimental and clinical studies, VEGF levels have been inversely correlated with survival. Moreover, VEGF inhibition has been shown to inhibit tumor growth and ascites production and to suppress tumor invasion and metastasis. These findings have laid the basis for the clinical evaluation of agents targeting VEGF signaling pathway in patients with ovarian cancer. In this review, we will focus on VEGF involvement in the pathophysiology of ovarian cancer and its contribution to the disease progression and dissemination.

Turning promise into progress for antiangiogenic agents in epithelial ovarian cancer

Despite efforts to improve chemotherapeutic efficacy in epithelial ovarian cancer, outcome for patients with advanced disease has remained unchanged since the introduction of standard carboplatin and paclitaxel. Interest has therefore shifted toward molecularly targeted therapies that interfere with important features of ovarian carcinogenesis, such as angiogenesis. Several angiogenesis inhibitors, targeting vascular endothelial growth factor (VEGF) ligands (bevacizumab, VEGF-Trap) or their receptors (VEGFR-targeted tyrosine kinase inhibitors) have been clinically evaluated. These agents demonstrated efficacy in phase II clinical trials. Results from phase III trials, in which bevacizumab was added to standard frontline chemotherapy, show a modest effect. Although the initial expectations for angiogenesis inhibitors have been tempered, further research is warranted to define their precise place in the treatment of ovarian cancer. This review summarizes the performed and ongoing studies with regard to angiogenesis inhibitors in ovarian cancer, and the available data on biomarkers for response prediction. Preclinical studies evaluating alternative angiogenesis inhibitors will also be discussed.