Plerixafor is effective and safe for stem cell mobilization in heavily pretreated germ cell tumor patients

Up to 10% of germ cell tumor patients require salvage high-dose chemotherapy with stem cell support, achieving cure rates in the range of 10-60%. Stem cell mobilization may be difficult in these patients because of multiple lines of treatment known to seriously hamper stem cell recovery. Plerixafor significantly enhances the success of the CD34+ cell harvest, even in cases where prior mobilization attempts have failed. Six germ cell tumor patients provided informed consent and were included in the compassionate use program. All patients were heavily pretreated, with a median of 3.5 prior lines of therapy. All failed prior mobilization with G-CSF in combination with chemotherapy. Five patients yielded a median of 2.6 × 10(6) CD34+ cells per kg body weight in a median of 4 apheresis days when plerixafor was used. Three patients underwent subsequent high-dose chemotherapy with autologous stem cell support. Median time to leukocyte engraftment was 11 days. Median time to platelet engraftment was 12.5 days, both of which are comparable to previous historical data. Accordingly, plerixafor seems to be safe and effective in germ cell tumor patients who have failed prior mobilization therapy. Larger prospective studies are warranted to further assess its use in germ cell cancer.

Microcirculation of secondary bone tumors in vivo: the impact of minor surgery at a distal site

Microcirculatory properties of tumors play a pivotal role in tumor progression and inefficacy of therapies. It has been hypothesized that surgical interventions result in an accelerated tumor growth by increasing the level of pro-angiogenic cytokines with subsequent amplification of tumor angiogenesis. To characterize the microvascular properties of secondary bone tumors in vivo and determine the impact of minor surgery on the microcirculation, we performed intravital microscopy over 25 days using a xenograft model of breast cancer tumor growth (MCF-7) in bone. After engraftment of tumors the mice were treated with a mastectomy versus no surgery. Tumor growth was accompanied by angiogenic sprouting and decreased vascular diameters while blood flow rate and tumor perfusion remained constant. Mastectomy initially led to a significant reduction of functional vascular density, increased vascular diameter, and decreased blood flow velocities. However, neither tumor growth nor tissue perfusion was different between the groups. The presented study corroborates the assumption that tumor microcirculation in bone exhibits similar time-dependent alterations compared to soft tissue tumors. A minor surgical intervention did not change tumor growth kinetics however microcirculatory properties were altered. Whether major surgery has an impact on tumor growth in bone should be clarified in further studies.

Factors affecting the unexpected failure of DCE-MRI to determine the optimal biological dose of the vascular targeting agent NGR-hTNF in solid cancer patients

INTRODUCTION

To understand which factors could affect the assessment of anti-vascular treatment by DCE-MRI, we investigated possible causes that could have hampered the selection of an optimal biological dose in humans of the vascular targeted agent NGR-hTNF by DCE-MRI: (1) insufficient reproducibility of DCE-MRI; (2) less specific targeting of NGR-hTNF; (3) interference of vessel characteristics with NGR-hTNF efficacy; (4) interfering pharmacodynamic effects.

EXPERIMENTAL

In a phase I study NGR-hTNF, DCE-MRI was performed at baseline and 2 h after NGR-hTNF administration in 31 patients with advanced solid cancer. Reproducibility measurements were performed in 5 other non-treated patients with metastatic disease. Mean kep, Ktrans values and their histogram distribution were determined in metastases and healthy liver tissue. The correlation between tumour size and DCE-MRI parameters was determined. Kinetics of soluble TNF receptors and the development of anti-TNF antibodies were assessed.

RESULTS

Reproducibility of the DCE-MRI technique was adequate. Mean DCE-MRI parameters did not significantly change after NGR-hTNF administration, but histogram analyses showed significant changes in metastases and healthy liver tissue in some patients. The anti-vascular effects of NGR-hTNF were larger in smaller tumours, which have less mature neovasculature. Soluble TNF receptors were released.

CONCLUSIONS

The difficulty to find an optimal biological dose of NGR-TNF by DCE-MRI is likely caused by a combination of factors: (i) different profiles of early anti-vascular effects in tumours and healthy liver tissue, (ii) dependence of the magnitude of the anti-vascular effect of NGR-hTNF on tumour size and (iii) shedding kinetics of soluble TNFα receptors.

Transmission dynamics of highly pathogenic avian influenza at Lake Constance (Europe) during the outbreak of winter 2005-2006

Highly pathogenic avian influenza virus (HPAI) H5N1 poses a serious threat to domestic animals. Despite the large number of studies on influenza A virus in waterbirds, little is still known about the transmission dynamics, including prevalence, behavior, and spread of these viruses in the wild waterbird population. From January to April 2006, the HPAI H5N1 virus was confirmed in 82 dead wild waterbirds at the shores of Lake Constance. In this study, we present simple mathematical models to examine this outbreak and to investigate the transmission dynamics of HPAI in wild waterbirds. The population dynamics model of wintering birds was best represented by a sinusoidal function. This model was considered the most adequate to represent the susceptible compartment of the SIR model. The three transmission models predict a basic reproduction ratio (R (0)) with value of approximately 1.6, indicating a small epidemic, which ended with the migration of susceptible wild waterbirds at the end of the winter. With this study, we quantify for the first time the transmission of HPAI H5N1 virus at Lake Constance during the outbreak of winter 2005-2006. It is a step toward the improvement of the knowledge of transmission of the virus among wild waterbirds.

Therapeutic potential and limitations of new FAK inhibitors in the treatment of cancer

IMPORTANCE OF THE FIELD

Activation of the non-receptor tyrosine kinase focal adhesion kinase (FAK) has been implicated in progression of multiple mesenchymal and epithelial malignant tumors. FAK plays an important role in regulation of proliferation, migration and apoptosis of neoplastic cells.

AREAS COVERED IN THIS REVIEW

We review the importance of FAK expression as a prognostic marker in cancer patients, discuss the available small-molecule inhibitors of FAK, summarize the available data from early-phase clinical trials with FAK inhibitors and cover the antiangiogenic properties of FAK inhibitors, as well as their potential to overcome chemoresistance.

WHAT THE READER WILL GAIN

This review enables the reader to overview current knowledge about FAK inhibition in cancer therapy and its role in the clinical setting. The reader will be able to consider FAK inhibitors not only as direct antitumor but also as antineoangiogenic agents and drugs that can overcome the problem of chemoresistance.

TAKE HOME MESSAGE

Emerging data from early-phase clinical trials with orally available small-molecule inhibitors of FAK are promising. There are early indicators of clinical efficacy. In the future, combination therapy with cytotoxic or antiangiogenic drugs may help to overcome chemoresistance and enhance efficacy of antivascular therapy.

Heterogenous high-level HER-2 amplification in a small subset of colorectal cancers

HER-2 is the molecular target for antibody-based treatment of breast cancer (trastuzumab). The potential benefit of anti-HER-2 therapy is currently investigated in several other HER-2 amplified cancers. For example, trastuzumab was recently shown to be effective in HER-2 positive gastric cancer. To address the potential applicability of anti-HER-2 therapy in colorectal cancer, tissue microarray sections and colorectal resection specimens of 1851 colorectal cancers were analyzed for HER-2 overexpression and amplification using FDA approved reagents for immunohistochemistry and fluorescence in situ hybridization. HER-2 amplification was seen in 2.5% and HER-2 overexpression in 2.7% of 1439 interpretable colorectal cancers. Amplification was often high level with HER-2 copies ranging from 4 to 60 per tumor cell and was strongly related to protein overexpression. HER-2 amplification and overexpression were unrelated to histological tumor type, tumor localization, grading, pT, pN, pM or survival. As heterogeneity of drug target expression could represent a major drawback for targeted cancer therapy we next studied HER-2 heterogeneity in selected cases. Extensive evaluation of all available large sections from patients with HER-2 positive colorectal cancer revealed heterogenous findings in 3 of 4 cases. In summary, high-level HER-2 amplification occurs in a small fraction of colorectal cancers. Heterogeneity of amplification may limit the utility of anti- HER-2 therapy in some of these tumors and therefore, adequate clinical trials are needed to further evaluate this approach.

Permanent Genetic Resources added to the Molecular Ecology Resources Database 1 February 2010-31 March 2010

This article documents the addition of 228 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Anser cygnoides, Apodemus flavicollis, Athene noctua, Cercis canadensis, Glis glis, Gubernatrix cristata, Haliotis tuberculata, Helianthus maximiliani, Laricobius nigrinus, Laricobius rubidus, Neoheligmonella granjoni, Nephrops norvegicus, Oenanthe javanica, Paramuricea clavata, Pyrrhura orcesi and Samanea saman. These loci were cross-tested on the following species: Apodemus sylvaticus, Laricobius laticollis and Laricobius osakensis (a proposed new species currently being described).

Tgf-Beta superfamily receptors-targets for antiangiogenic therapy?

The TGF-beta pathway controls a broad range of cellular behavior including cell proliferation, differentiation, and apoptosis of various cell types including tumor cells, endothelial cells, immune cells, and fibroblasts. Besides TGF-beta's direct effects on tumor growth and its involvement in neoangiogenesis have received recent attention. Germline mutations in TGF-beta receptors or coreceptors causing Hereditary Hemorrhagic Teleangiectasia and the Loeys-Dietz syndrome underline the involvement of TGF-beta in vessel formation and maturation. Several therapeutic approaches are evaluated at present targeting the TGF-beta pathway including utilization of antisense oligonucleotides against TGF-beta itself or antibodies or small molecule inhibitors of TGF-beta receptors. Some of these therapeutic agents have already entered the clinical arena including an antibody against the endothelium specific TGF-beta class I receptor ALK-1 targeting tumor vasculature. In conclusion, therapeutic manipulation of the TGF-beta pathway opens great opportunities in future cancer therapy.

Impact of IDH1 R132 mutations and an IDH1 single nucleotide polymorphism in cytogenetically normal acute myeloid leukemia: SNP rs11554137 is an adverse prognostic factor

PURPOSE

We assessed the prognostic impact of IDH1 R132 mutations and a known single nucleotide polymorphism (SNP) located in the same exon of the IDH1 gene in patients with cytogenetically normal acute myeloid leukemia (CN-AML) in the context of other prognostic markers.

PATIENTS AND METHODS

IDH1 exon four was directly sequenced in 275 CN-AML patients from two subsequent AML multicenter treatment trials and 120 healthy volunteers. Moreover, mutations in NPM1, FLT3, CEBPA, and WT1 were analyzed, and mRNA expression of IDH1 was quantified.

RESULTS

IDH1 R132 mutations were found in 10.9% of CN-AML patients. IDH1 SNP rs11554137 was found in 12% of CN-AML patients and 11.7% of healthy volunteers. IDH1 R132 mutations had no impact on prognosis. In contrast, IDH1 SNP rs11554137 was an adverse prognostic factor for overall survival in univariate and multivariate analysis. Other significant factors were age, NPM1/FLT3 mutational status, WT1 SNP rs16754, and platelet count. The impact of IDH1 SNP rs11554137 was most pronounced in the NPM1/FLT3 high-risk patients (either NPM1 wild-type or FLT3-internal tandem duplication positive). Patients with IDH1 SNP rs11554137 had a higher expression of IDH1 mRNA than patients with two wild-type alleles.

CONCLUSION

IDH1 SNP rs11554137 but not IDH1 R132 mutations are associated with an inferior outcome in CN-AML.

Phase I clinical and magnetic resonance imaging study of the vascular agent NGR-hTNF in patients with advanced cancers (European Organization for Research and Treatment of Cancer Study 16041)

PURPOSE

This phase I trial investigating the vascular targeting agent NGR-hTNF aimed to determine the (a) dose-limiting toxicities, (b) maximum tolerated dose (MTD), (c) pharmacokinetics and pharmacodynamics, (d) vascular response by dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), and (e) preliminary clinical activity in solid tumors.

EXPERIMENTAL DESIGN

NGR-hTNF was administered once every 3 weeks by a 20- to 60-minute i.v. infusion to cohorts of three to six patients with solid tumors in escalating doses. Pharmacokinetic and pharmacodynamic analyses in blood were done during the first four cycles. DCE-MRI was done in cycle 1 at baseline and 2 hours after the start of the infusion.

RESULTS

Sixty-nine patients received a total of 201 cycles of NGR-hTNF (0.2-60 microg/m(2)). Rigors and fever were the most frequently observed toxicities. Four dose-limiting toxicities were observed (at doses of 1.3, 8.1, and 60 microg/m(2)), of which three were infusion related. The MTD was 45 microg/m(2). The mean apparent terminal half-life ranged from 0.963 to 2.08 hours. DCE-MRI results of tumors showed a vascular response to NGR-hTNF. No objective responses were observed, but 27 patients showed stable disease with a median duration of 12 weeks.

CONCLUSIONS

NGR-hTNF was well tolerated. The MTD was 45 microg/m(2) administered in 1 hour once every 3 weeks. DCE-MRI results showed the antivascular effect of NGR-hTNF. These findings call for further research for defining the optimal biological dose and clinical activity of NGR-hTNF as a single agent or in combination with cytotoxic drugs.

Single Nucleotide Polymorphism in the Mutational Hotspot of WT1 Predicts a Favorable Outcome in Patients With Cytogenetically Normal Acute Myeloid Leukemia

Purpose

We assessed the prognostic impact of a known single nucleotide polymorphism (SNP) located in the mutational hotspot of WT1 in patients with cytogenetically normal acute myeloid leukemia (CN-AML) in the context of other prognostic markers.

Patients and Methods

WT1 exons 7 and 9 from 249 CN-AML patients from multicenter treatment trials AML-SHG Hannover 0199 (Clinical Trials Identifier NCT00209833) and 0295, and 50 healthy volunteers were analyzed by direct sequencing. NPM1, FLT3, CEBPA, and MLL were assessed for mutations and WT1 expression was quantified.

Results

The minor allele of SNP rs16754 (WT1AG/GG) was found in 25.7% of CN-AML patients' blasts and germline DNA and in 36% of healthy volunteers. Patient characteristics, frequencies of mutations, or WT1 expression levels were similarly distributed between patients homozygous for the major allele compared with patients heterozygous or homozygous for the minor allele. SNP rs16754 status was an independent predictor of relapse-free survival (RFS; hazard ratio [HR], 0.49; 95% CI, 0.3 to 0.81; P = .005) and overall survival (OS; HR, 0.44; 95% CI, 0.27 to 0.74; P = .002) in multivariate analysis. The favorable effect of SNP rs16754 was stronger in NPM1/FLT3-ITD (internal tandem duplication of the FLT3 gene) high-risk patients compared with NPM1/FLT3-ITD low-risk patients. Favorable prognosis could not be identified by any other known low-risk marker in half the patients with at least one minor allele (13% of all patients). No difference for complete remission rate, RFS, or OS was found between patients with or without acquired WT1 mutations.

Conclusion

WT1 SNP rs16754 may be a novel independent favorable-risk marker in CN-AML patients that might improve risk and treatment stratification.

Primary NK/T cell lymphoma nasal type of the stomach with skin involvement: a case report

Since nasal NK/T cell lymphoma and NK/T cell lymphoma nasal type are rare diseases, gastric involvement has seldom been seen. We report a unique case of a patient with a primary NK/T cell lymphoma nasal type of the stomach with skin involvement. The patient had no history of malignant diseases and was diagnosed with hematemesis and intense bleeding from his gastric primary site. Shortly after this event, exanthemic skin lesions appeared with concordant histology to the primary site. Despite chemotherapy, the patient died one month after the first symptomatic appearance of disease.

Effective strategies for management of hypertension after vascular endothelial growth factor signaling inhibition therapy: results from a phase II randomized, factorial, double-blind study of Cediranib in patients with advanced solid tumors

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.

Characterisation of extramedullary relapse in patients with chronic myeloid leukemia in advanced disease after allogeneic stem cell transplantation

Recently, higher extramedullary relapse rates following allogeneic stem cell transplantation (SCT) in myeloid malignancies were reported e.g. because of selection of poor-risk patients. We analysed five consecutive patients with post-transplant extramedullary relapse of chronic myeloid leukemia (CML) out of a total of 24 patients (21%) undergoing allo-SCT. All five patients with extramedullary relapse had clonal evolution and a history of blast phase (BP). In particular, 56% of the patients in BP had extramedullary relapse with no extramedullary relapse in patients with chronic/accelerated phase. Most frequent manifestation sites were the skeletal system, the muscles/subcutaneous tissue and the central nervous system. In one case chloroma was mimicking myositis of the lower limbs. Combined approaches were performed including irradiation (n = 4), chemotherapy (n = 2), IM (n = 2), dasatinib (n = 4), nilotinib (n = 1), a novel aurora-kinase-inhibitor (n = 1), donor lymphocytes (n = 2) or a second allo-SCT (n = 2). Transient response was achieved in one case, stable partial remissions in two cases, whereas two cases were refractory. Research should focus on prospective studies aiming to improve treatment of extramedullary relapse in stem cell recipients with CML with a special focus on the role of second generation tyrosine kinase inhibitors.

Analysis of expression of TGF-β1 receptor (ALK-1) in normal and tumor tissues by tissue microarrays

e22044

Background: TGF-β1 is an important angiogenic factor involved in different aspects of angiogenesis and vessel maintenance. TGF-β1 receptors consist of class I, class II and accessory receptors. Activin-like kinase I (ALK-1) is a class I TGF- β1 receptor which is almost exclusively expressed on endothelial cells. Hereditary hemorrhagic telangiectasia (HHT) is caused by mutations in the ALK-1 gene. Knock-out mice for ALK-1 die during gestation due to vascular malformation. ALK-1 may thus represent an attractive target for anti-angiogenic therapy. A therapeutic monoclonal antibody (PF-03446962) against ALK-1 has been developed which is currently in phase I testing. Here we describe target validation in normal and tumor tissue using tissue micro-arrays (TMAs). Methods: Normal tissue arrays comprised of 609 individual histological samples representing 76 human tissues. Multi-tumor arrays consisted of 3923 individual tumor samples from 87 tumor types. Consecutive sections of tissue arrays were stained for ALK-1 and CD31. CD31 immunohistology (IHC) was performed to ensure presence of vessels within tissue samples. ALK-1 staining was graded 0=absent, 1=weak, 2= moderate and 3=strong by an experienced pathologist blinded to tissue type. Results: ALK-1 staining of vessels in normal tissues was generally weak (mostly grade 1 and rarely grade 2) and was detectable in lymphatic tissues including tonsil, lymph nodes, thymus and spleen, lung, the entire GI tract including parotid, submandibular and sublingual glands as well as pancreas. ALK-1 positive vessels were also found within the female genital tract including placenta, uterus and ovary. In human tumor vessels ALK-1 expression showed high variability between tumor types. The highest ALK-1 expression rate was found in lung cancer (NSCLC 49%, SCLC 83%), neuroendocrine pancreas tumor (71%), colon cancer (50%), chondrosarcoma 50%, angiosarcoma 40% and NHL (44%). Conclusions: TMAs are an excellent tool to verify target expression in normal and tumor tissues. Results may be used to predict side effects of targeted therapy and to direct phase II testing of innovative agents in patients likely to respond.

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Cilengitide induces cellular detachment and apoptosis in endothelial and glioma cells mediated by inhibition of FAK/src/AKT pathway

BACKGROUND

The antiangiogenic agent cilengitide disrupts integrin binding to the extracellular matrix leading to apoptosis of activated endothelial cells. Integrins are also widely expressed in malignant glioma and integrin inhibitors may directly target tumor cells in this disease. Aim of the current study was to investigate effects of cilengitide on endothelial and glioma cells on molecular and cellular levels.

RESULTS

Cilengitide caused dose-dependent detachment of endothelial cells from cell culture dishes. Proliferation of endothelial cells was significantly inhibited while the proportion of apoptotic cells was increased. Incubation of integrin-expressing glioma cells with cilengitide caused rounding and detachment after 24 hours as observed with endothelial cells. Cilengitide inhibited proliferation and induced apoptosis in glioma cells with methylated MGMT promotor when given alone or in combination with temozolomide. In endothelial as well as glioma cells cilengitide inhibited phosphorylation of FAK, Src and Akt. Assembly of cytoskeleton and tight junctions was heavily disturbed in both cell types.

CONCLUSION

Cilengitide inhibits integrin-dependent signaling, causes disassembly of cytoskeleton, cellular detachment and induction of apoptosis in endothelial and glioma cells thereby explaining the profound activity of integrin inhibitors in gliomas. The combination of cilengitide with temozolomide exerted additive effects in glioma cells as observed clinically.