- [Show abstract] [Hide abstract] ABSTRACT: Atu027 is a novel liposomal RNA interference therapeutic that includes a short-interfering RNA (siRNA), which silences expression of protein kinase N3 in the vascular endothelium. Atu027 has previously been shown to inhibit local tumor invasion as well as lymph node and pulmonary metastasis in mouse cancer models. This first-in-human study aimed to assess the safety, tolerability, and pharmacokinetics of Atu027 while evaluating therapeutic effects on both primary tumors and metastatic lesions. Thirty-four patients with advanced solid tumors received 10 escalating doses of Atu027 without premedication, as one single followed by eight intravenous infusions twice per week during a 28-day cycle. Response was monitored by computed tomography/magnetic resonance imaging at baseline, at the end of treatment (EoT), and at final follow-up (EoS), and was assessed according to RECIST. Atu027 was well tolerated up to dose levels of 0.336 mg/kg; most adverse events (AEs) were low-grade toxicities (grade 1 or 2). No maximum tolerated dose was reached. Plasma levels of siRNA strands and lipids were dose proportional, peaking during 4-hour infusion. Disease stabilization was achieved in 41% of patients at EoT (n = 14 of 34 treated patients); eight patients had stable disease at EoS, and some experienced complete or partial regression of metastases. sFLT1 (soluble variant of vascular endothelial growth factor receptor-1) decreased from pretreatment levels in most patients after dose levels 04 to 10. Atu027 was safe in patients with advanced solid tumors, with 41% of patients having stable disease for at least 8 weeks. In view of these results, further clinical trials have been initiated, and sFLT1 will be investigated as a potential biomarker. © 2014 by American Society of Clinical Oncology.
- [Show abstract] [Hide abstract] ABSTRACT: Background and objective: Auron Misheil therapy (AMT) is a combination of widely used pharmaceuticals and herbal components that has been used since the 1980s as a supportive therapy, mainly in end-stage cancer patients on a compassionate basis. This phase I study was conducted to assess the safety, tolerability, and pharmacokinetic (PK) and pharmacodynamic (PD) properties of AMT in a controlled trial environment. Methods: The study was conducted in a single rising dose, double-blind, placebo-controlled design. Three groups of eight healthy male volunteers received one of three doses of AMT (0·011, 0·033 or 0·066 mL AMT/kg body weight intramuscularly; n = 6 per group) or placebo (n = 2 per group). Results and discussion: Auron Misheil therapy was shown to be well tolerated, revealing no severe or serious adverse events. There were no unexpected PK or PD results for any of the three components of AMT. Conclusions: These data provide important PK, PD and safety data for AMT, and support further controlled clinical investigation in patients with different types of cancer as an option for supportive care.
- [Show abstract] [Hide abstract] ABSTRACT: Tumor AngiogenesisAntiangiogenesisBiomarkers in Antiangiogenic Drug DevelopmentTissue MarkersBlood MarkersImaging TechniquesSummaryReferences
- [Show abstract] [Hide abstract] ABSTRACT: Tumor angiogenesis has been identified to play a critical role in tumor growth and tumor progression, and is regulated by a balance of angiogenic and anti-angiogenic cytokines. Among them VEGF (vascular endothelial growth factor) and its signaling through its receptors are of crucial relevance. Inhibition of VEGF signaling by monoclonal antibodies or small molecules (kinase inhibitors) has already been successfully established for the treatment of different cancer entities and multiple new drugs are being tested in clinical trials. However not all patients are likely to respond to these therapies, but to date there are no reliable biomarkers available to predict therapy response. Many studies integrated biomarker programs in their study protocols, thus several potential biomarkers have been identified which are currently under clinical investigation in prospective randomized studies. This review intends to give an overview of the described potential biomarkers as well as different imaging techniques such as ultrasound and magnetic resonance imaging that can indicate benefit, resistance and toxicity to anti-angiogenic therapies.
- [Show abstract] [Hide abstract] ABSTRACT: Combining different targeted anticancer agents may improve clinical outcomes. This Phase I study investigated cediranib, an oral inhibitor of vascular endothelial growth factor signalling in combination with saracatinib, an oral Src inhibitor. The primary endpoint was safety/tolerability. Secondary assessments included pharmacokinetics and preliminary efficacy. Patients with advanced solid tumours received cediranib 20, 30 or 45 mg/day for 7 days followed by daily treatment with cediranib at the same dose plus saracatinib 175 mg/day. Thirty-nine patients received cediranib (20 mg, n = 6; 30 mg, n = 6; 45 mg, n = 27 [n = 20 in cohort expansion]) plus saracatinib. In the cediranib 45 mg cohort, 59% of patients required dose reduction/pause compared with 33% in each of the other two cohorts. There was one dose-limiting toxicity (hypertension; 45 mg cohort). The most common adverse events were hypertension (67%), diarrhoea (62%), dysphonia (46%) and fatigue (39%). There was no evidence of a clinically significant effect of saracatinib on cediranib pharmacokinetics and vice versa. 22/35 evaluable patients had a best response of stable disease. All cediranib doses were tolerated; however, in patients with advanced solid tumours, for combination with saracatinib 175 mg/day, cediranib 20 or 30 mg/day was more sustainable than 45 mg/day.
- [Show abstract] [Hide abstract] ABSTRACT: Hepatocellular carcinoma (HCC) has a poor prognosis and systemic chemotherapies have disappointing results. The increasing knowledge of the molecular biology of HCC has resulted in novel targets, with the vascular endothelial growth factor and epidermal growth factor receptor (EGFR)-related pathways being of special interest. New blood vessel formation (angiogenesis) is essential for the growth of solid tumors. Anti-angiogenic strategies have become an important therapeutic modality for solid tumors. Several agents targeting angiogenesis-related pathways have entered clinical trials or have been already approved for the treatment of solid tumors. These include monoclonal antibodies, receptor tyrosine kinase inhibitors and immunomodulatory drugs. HCC is a highly vascular tumor, and angiogenesis is believed to play an important role in its development and progression. This review summarizes recent advances in the basic understanding of the role of angiogenesis in HCC as well as clinical trials with novel therapeutic approaches targeting angiogenesis and EGFR-related pathways.
- [Show abstract] [Hide abstract] ABSTRACT: ZD6126 is a vascular-disrupting agent that affects the endothelial tubulin cytoskeleton causing selective occlusion of tumor vasculature and extensive tumor cell necrosis. The present study evaluated the antitumor and antivascular activities of ZD6126 in the clinically relevant murine renal cell carcinoma (RENCA) model and also evaluated biological response to therapy using color Doppler imaging as biomarker. Mice were implanted with RENCA tumor cells (day 0) and established tumors were treated with ZD6126 (100 mg/kg i.p.) or vehicle with repeated intermittent doses on day 10, 14 and 18. ZD6126 treatment led to a significant reduction in tumor size and was associated with extensive tumor necrosis and a reduction in tumor blood flow versus controls. MVD increased with intermittent treatment (day 10, 14 and 18). In an additional study, animals were treated at day 19 and quantitative three-dimensional microvascular corrosion casting was performed to enable detailed assessment of the tumor vascular architecture. Corrosion casting showed that tumor vessel architecture is affected by treatment, whereas pre-existing vessels in control tissues are practically not affected. Inter-vessel and inter-branch distances as well as vessel diameters are influenced by treatment. In conclusion, ZD6126 showed potent antitumor efficacy in the RENCA model and our data suggest that decrease in tumor blood flow may be a useful surrogate marker of treatment effect.
- [Show abstract] [Hide abstract] ABSTRACT: PTK787/ZK 222584 (PTK/ZK) offers a novel approach to inhibit tumour angiogenesis. This study characterized the safety, tolerability, biological activity and pharmacokinetic profile of PTK/ZK, while determining the optimum dose. Seventy-one patients with advanced cancer were enrolled to receive once daily dosing. Pharmacokinetic, dynamic contrast enhanced magnetic resonance imaging and safety assessments were performed, along with measurement of soluble markers. Patients were treated until they had unacceptable toxicity and/or disease progression. Twenty-nine patients were assessable for maximum tolerated dose (MTD) determination, but no MTD was established; only two patients experienced dose limiting toxicities. PTK/ZK was well tolerated with only nine patients experiencing serious adverse events suspected to be PTK/ZK related, but no objective tumour response was observed; 34% had stable disease and 48% had progressive disease. In addition, PTK/ZK was rapidly absorbed with a maximum concentration occurring 2 hours post-dosing. Vascular endothelial growth factor and basic fibroblastic growth factor were good predictors of best tumour response, as was the MRI bidirectional transfer constant on day 2 of treatment. An MTD was not reached in this study but, based on these data and findings from other studies, 1200 mg was found to be the optimum dose of PTK/ZK for patients with advanced cancer.
- [Show abstract] [Hide abstract] ABSTRACT: Auron-Misheil-Therapy (AMT) is a defined but unique combination of approved pharmaceuticals. It consists of insulin, chlorpheniramine and an aqueous camomile extract, and it has been successfully applied clinically in late-stage cancer patients. The purpose of this study was to elucidate the anti-tumor efficacy of AMT in a validated murine renal cell carcinoma animal model (RENCA). There were two independent studies; each animal group consisted of 16 mice. During a 6-week pretreatment period, vehicle (group A) and AMT (1.6 mg/kg/d) (group B) were administered once daily in a 5 days/week schedule either intramuscularly or subcutaneously. Tumor challenge at day 0 was followed by a 3-week treatment period (either vehicle or AMT once daily intramuscularly for 21 days consecutively). In study 2 the AMT dosage was increased up to 4-fold by doubling individual doses and switching to a twice daily schedule. The injections were all intramuscular. With the exception of group D, a six-week pretreatment period preceded the tumor challenge at day 0. Tumor challenge was followed by a 3-week treatment period (vehicle, AMT at either 3.2 mg/kg/d) (group A) or 6.4 mg/kg/d (group B), or AMT0, an AMT preparation which does not stimulate IL-6 secretion (6.4 mg/kg/d, group C) continuously for 21 days. AMT administration for group D (6.4 mg/kg/d) was limited to the treatment period from day 1 to 21. All mice were sacrificed 21 days after tumour transplantation. AMT administration was safe and well tolerated, and significantly reduced primary tumor volume in pretreated animals. The effective route of application was intramuscular, with dose escalation resulting in an improved anti-tumor effect. This is the first demonstration of a significant anti-tumorigenic effect of AMT in a validated tumor model.
- [Show abstract] [Hide abstract] ABSTRACT: Cediranib is a highly potent and selective vascular endothelial growth factor (VEGF) signaling inhibitor with activity against all three VEGF receptors (VEGFRs) that inhibits angiogenesis and growth of human tumor xenografts in vivo. The present study evaluated the antitumor and antiangiogenic activity of cediranib in the clinically relevant, murine renal cell carcinoma (RENCA) model and its biological response using VEGF and sVEGFR-2 as biomarkers. Mice were treated with cediranib (5 mg/kg/d p.o.) or vehicle for 2, 8 or 12 days and tumor volumes, microvessel density (MVD) and VEGF and sVEGFR-2 plasma concentrations were determined. Cediranib treatment (8 and 12 days) led to a significant reduction in tumor size (42-50%) and a highly significant reduction in MVD (30-55%) versus controls. After 12 days' treatment, VEGF plasma concentration increased significantly in both cediranib-treated and control animals and this increase correlated with tumor size; the cediranib group showed a more pronounced increase in VEGF but a reduced tumor volume compared with control animals. Plasma concentrations of VEGF reached a plateau in the cediranib group after 17-21 days' treatment. sVEGFR-2 concentrations significantly decreased over 12 days in controls, whereas they remained stable in cediranib-treated mice. sVEGFR-2 did not correlate with tumor volume in controls; mice treated with cediranib had lower relative VEGFR-2 plasma concentrations and tumor burdens. In conclusion, cediranib showed potent antitumor and antiangiogenic efficacy in the RENCA model. sVEGFR-2 plasma concentrations can act as a surrogate marker for antitumor activity of VEGFR signaling inhibitors.
- [Show abstract] [Hide abstract] ABSTRACT: This pilot study of Auron Misheil Therapy (AMT) in women with advanced cervical cancer was an open-label, single arm study to collect initial safety, efficacy, and quality of life data. Fifteen women with stage IIIb or IVa cervical cancer were given twice daily intramuscular injections of AMT (insulin, chlorpheniramine and camomile extract) for 3 months. Objective tumor response was evaluated using CT scans and analyzing the data according to the WHO RECIST criteria. Clinical Benefit Response (CBR) was assessed using a composite score comprising Karnovsky performance status, pain intensity and body weight. Safety and tolerability parameters were monitored. Quality of life was evaluated using the European Organization for Research and Treatment of Cancer Core Quality of Life Questionnaire (EORTC C-30). Eight out of 15 patients were rated as clinical responders (CBR) at 12 weeks. One patient had a partial response and 11 stable disease (WHO RECIST criteria). AMT was well tolerated. An initial analysis showed improvement in quality of life (EORTC C-30). Promising response rates, early indications of improved quality of life, and no significant safety issues mean that the second, randomized phase of the trial can be initiated with a longer treatment duration. Patients with advanced cervical cancer showed positive clinical responses to Auron Misheil Therapy. The treatment was well tolerated, with indications of improved quality of life.
- [Show abstract] [Hide abstract] ABSTRACT: PURPOSE Hypertension is a commonly reported adverse effect after administration of vascular endothelial growth factor (VEGF) inhibitors. Cediranib is a highly potent and selective VEGF signaling inhibitor of all three VEGFRs. This study prospectively investigated hypertension management to help minimize dose interruptions/reductions to maximize cediranib dose intensity. PATIENTS AND METHODS Patients (n = 126) with advanced solid tumors were randomly assigned to one of four groups: cediranib 30 or 45 mg/d with or without antihypertensive prophylaxis. All patients developing hypertension on cediranib treatment were treated with a standardized, predefined hypertension management protocol. Results Cediranib was generally well tolerated, and all groups achieved high-dose intensities in the first 12 weeks (> 74% in all groups). Antihypertensive prophylaxis did not result in fewer dose reductions or interruptions. Increases in blood pressure, including moderate and severe readings of hypertension, were seen early in treatment in all groups and successfully managed. Severe hypertension occurred in one patient receiving prophylaxis versus 18 in the nonprophylaxis groups. Overall, there were nine partial responses, and 38 patients experienced stable disease >/= 8 weeks. CONCLUSION To our knowledge, this is the first prospective investigation of hypertension management during administration of a VEGF signaling inhibitor. All four regimens were well tolerated with high-dose intensities and no strategy was clearly superior. The current cediranib hypertension management protocol appears to be effective in managing hypertension compared with previous cediranib studies where no plan was in place, and early recognition and treatment of hypertension is likely to reduce the number of severe hypertension events. This protocol is included in all ongoing cediranib clinical studies.
- [Show abstract] [Hide abstract] ABSTRACT: Auron-Misheil-Therapy (AMT) consisting of aqueous camomile extract supplemented with calcium, vitamins, the antihistamine chlorpheniramine and human insulin is under development as anti-cancer treatment. AMT was preclinically investigated in tumour cell lines and tumour xenografts to guide clinical phase I/II studies. AMT was tested against 56 human tumour cell lines, in a clonogenic assay in 98 patient-derived xenografts and in in vivo studies. AMT showed in vitro cytotoxic activity with highest susceptibility in cervical cancer, glioblastoma and colon cancers. In the clonogenic assay, anti- cancer activity of AMT was most active in cervical and uterine tumours, in colon cancer, glioblastoma, leukaemia, melanoma and pancreatic cancer. In vivo, AMT showed slight activity in tumour xenograft models of colon and mammary cancer. It also showed immune stimulatory effects by induction of IL-6- and TNF-alpha secretion in human PBMCs. The immune stimulatory potential of AMT, together with slight anti-tumour efficacy observed in the present study, indicates a role of AMT in tumour therapy.
- [Show abstract] [Hide abstract] ABSTRACT: The established role of VEGF signaling in promoting tumor angiogenesis has led to the development and clinical validation of several agents that selectively target this pathway in patients with advanced-stage malignancies. These include neutralizing anti-VEGF monoclonal antibodies, soluble VEGF receptors and small-molecule inhibitors of VEGF receptor function, administered either as monotherapy or in combination with chemotherapy. Several modes of action have been identified, such as inhibition of new vessel growth, regression of newly formed vasculature, alteration of tumor vessel function and direct effects on tumor cells. VEGF-targeting drugs currently play an important role in the treatment of cancer and their impact will probably further increase in the future.
- [Show abstract] [Hide abstract] ABSTRACT: This review will provide physicians and oncologists with an overview of side effects related to targeted agents that inhibit vascular endothelial growth factor (VEGF), epidermal growth factor (EGF) and mammalian target of rapamycin (mTOR) signaling in the treatment of solid tumors. Such targeted agents can be divided into monoclonal antibodies, tyrosine kinase inhibitors, multitargeted tyrosine kinase inhibitors and serine/threonine kinase inhibitors. Molecular targeted therapies are generally well tolerated, but inhibitory effects on the biological function of the targets in healthy tissue can result in specific treatment-related side effects, particularly with multitargeted agents. We offer some guidance on how to manage adverse events in cancer patients based on the range of options currently available.
Chapter: Tumor Angiogenesis[Show abstract] [Hide abstract] ABSTRACT: Since the first description of angiogenesis and the discovery of its crucial role in tumor growth, extensive efforts have been made to develop antiangiogenic drugs. Some targeted therapies have been established as the first-line therapy in certain tumor types. However, the pathophysiological principles are not fully understood, and little is known about the interaction of antiangiogenic drugs in combination with other classical antitumoral therapies like chemotherapy or radiation. A combination of all three strategies represents a very powerful tool to treat cancer aggressively, but also increases the risk of side effects. To understand the rationale of these combinational therapies, it is critically important to understand the angionesis and pathophysiology of antiangiogenic drugs on the one hand and the effects of radiation and chemotherapy on the other.
- [Show abstract] [Hide abstract] ABSTRACT: In a phase-III trial it was recently shown that an adjuvant renal cell carcinoma (RCC) vaccine (Reniale) reduces the risk of tumour progression following nephrectomy. This clinical trial focused on efficacy and did not investigate end-points relating to mode-of-action of the vaccine. In a murine model we investigated mode-of-action, efficacy, and safety of a homologous RENCA cell-based vaccine. Six groups with 12 BALB/c mice per group received five vaccinations (lysate of 1x10(6)-1x10(7) RENCA cells, manufactured with or without prior IFN-gamma incubation) at 3-wk intervals before tumour transplantation and one vaccination 14 d afterwards. Controls (12 mice) received only solvent. All mice were sacrificed 21 d after tumour transplantation. Animal welfare, tumour growth, number of metastases, and the presence of cytotoxic T-lymphocytes as determined by a (51)chromium-release assay. Adoptive immune transfer experiments (vaccination of nine mice with the RENCA vaccine or saline and transfer of serum, spleen cells, and CD4 and/or CD8 depleted spleen cells into five recipient mice each) were carried out to demonstrate involvement of different immune mechanisms. All controls developed a renal tumour, compared to 7/72 animals (9.7%) in the vaccine groups. The mean number of lung metastases was 100 (range 3-750) in controls and 4 (range 0-196) in the vaccine groups, respectively. Tumour uptake and number of metastases were not related to the vaccine dose. The (51)chromium-release assay confirmed a significant tumour-specific cytolytic activity and marginally increased NK activity of splenocytes from vaccinated mice against RENCA cells compared to controls. Adoptive immune transfer experiments showed that the antitumoural effective immune mechanisms are cell-based. We could demonstrate the mode-of-action, efficacy, and safety of a homologous tumour vaccine in a RENCA model. These findings support the positive results from a phase-III trial with Reniale.
- [Show abstract] [Hide abstract] ABSTRACT: To study prospectively the plasma levels of vascular endothelial growth factor (VEGF-A), its soluble receptors sVEGFR-1, sVEGFR-2 and soluble Tie2 in premature infants. To identify their changes related to the onset of retinopathy of prematurity (ROP). Blood samples of 63 preterm infants born at a postmenstrual age (PMA) of 23-32 weeks were obtained between 5 days and 15 weeks after birth. 42 infants had no ROP, two had stage 1, nine stage 2 and 10 stage 3. Of these, four infants were treated with retinal photocoagulation. VEGF-A, sVEGFR-1, sVEGFR-2, and sTie2 were measured in the plasma with a sandwich enzyme immunoassay using factor-specific monoclonal mouse antibodies. The time course of concentrations plotted by kernel smoothing in infants with and without ROP were compared and a paired subgroup with analysis of variance was analysed. ROP patients had raised plasma levels of sVEGFR-2 and sTie2 compared with premature infants without ROP. VEGF-A and sVEGFR-1 levels were similar in both groups. Analysis of a subgroup with pairs of measurements, one before 32 weeks and one after 36 weeks, showed a significant increase in sTie2 after 36 weeks of PMA independent of ROP (p = 0.03). This is the first study to measure plasma levels of angiogenic factors in ROP. Similar VEGF-A plasma levels in infants with and without ROP suggest that pathogenic retinal angiogenesis in ROP is mainly driven by local VEGF-A synthesis. Elevated plasma levels in active ROP were observed for sVEGFR-2 and sTie2. These increases have yet to be confirmed as predictive values for ROP.
Evangelische Hochschule Freiburg, GermanyFreiburg, Baden-Württemberg, Germany
Clinic for Tumor Biology FreiburgFreiburg, Baden-Württemberg, Germany
University of FreiburgFreiburg, Baden-Württemberg, Germany