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Abstract 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.

Rationale : CD38 is a target for the therapy of multiple myeloma (MM) with monoclonal antibodies such as daratumumab and isatuximab. Since MM patients exhibit a high rate of relapse, the development of new biologics targeting alternative CD38 epitopes is desirable. The discovery of single-domain antibodies (nanobodies) has opened the way for a new generation of antitumor therapeutics. We report the generation of nanobody-based humanized IgG1 heavy chain antibodies (hcAbs) with a high specificity and affinity that recognize three different and non-overlapping epitopes of CD38 and compare their cytotoxicity against CD38-expressing hematological cancer cells in vitro , ex vivo and in vivo . Methods : We generated three humanized hcAbs (WF211-hcAb, MU1067-hcAb, JK36-hcAb) that recognize three different non-overlapping epitopes (E1, E2, E3) of CD38 by fusion of llama-derived nanobodies to the hinge- and Fc-domains of human IgG1. WF211-hcAb shares the binding epitope E1 with daratumumab. We compared the capacity of these CD38-specific hcAbs and daratumumab to induce CDC and ADCC in CD38-expressing tumor cell lines in vitro and in patient MM cells ex vivo as well as effects on xenograft tumor growth and survival in vivo . Results : CD38-specific heavy chain antibodies (WF211-hcAb, MU1067-hcAb, JK36-hcAb) potently induced antibody-dependent cellular cytotoxicity (ADCC) in CD38-expressing tumor cell lines and in primary patient MM cells, but only little if any complement-dependent cytotoxicity (CDC). In vivo, CD38-specific heavy chain antibodies significantly reduced the growth of systemic lymphomas and prolonged survival of tumor bearing SCID mice. Conclusions : CD38-specific nanobody-based humanized IgG1 heavy chain antibodies mediate cytotoxicity against CD38-expressing hematological cancer cells in vitro , ex vivo and in vivo . These promising results of our study indicate that CD38-specific hcAbs warrant further clinical development as therapeutics for multiple myeloma and other hematological malignancies., Competing Interests: Competing Interests: K.S., W.F., L.S., S.M., P.B., and F.K.-N. are co-inventors on a patent application on CD38-specific nanobodies. F.H. and F.K.-N. receive a share of antibody and protein sales via MediGate GmbH, a wholly owned subsidiary of the University Medical Center Hamburg-Eppendorf., (© The author(s).)

The NAD-hydrolyzing ecto-enzyme CD38 is overexpressed by multiple myeloma and other hematological malignancies. We recently generated CD38-specific nanobodies, single immunoglobulin variable domains derived from heavy-chain antibodies naturally occurring in llamas. Nanobodies exhibit high solubility and stability, allowing easy reformatting into recombinant fusion proteins. Here we explore the utility of CD38-specific nanobodies as ligands for nanobody-based chimeric antigen receptors (Nb-CARs). We cloned retroviral expression vectors for CD38-specific Nb-CARs. The human natural killer cell line NK-92 was transduced to stably express these Nb-CARs. As target cells we used CD38-expressing as well as CRISPR/Cas9-generated CD38-deficient tumor cell lines (CA-46, LP-1, and Daudi) transduced with firefly luciferase. With these effector and target cells we established luminescence and flow-cytometry CAR-dependent cellular cytotoxicity assays (CARDCCs). Finally, the cytotoxic efficacy of Nb-CAR NK-92 cells was tested on primary patient-derived CD38-expressing multiple myeloma cells. NK-92 cells expressing CD38-specific Nb-CARs specifically lysed CD38-expressing but not CD38-deficient tumor cell lines. Moreover, the Nb-CAR-NK cells effectively depleted CD38-expressing multiple myeloma cells in primary human bone marrow samples. Our results demonstrate efficacy of Nb-CARs in vitro. The potential clinical efficacy of Nb-CARs in vivo remains to be evaluated., Competing Interests: K.S., P.B., and F.K.-N. are co-inventors on a patent application on CD38-specific nanobodies. F.H. and F.K.-N. receive a share of antibody and protein sales via MediGate GmbH, a wholly owned subsidiary of the University Medical Center Hamburg-Eppendorf. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.

Heatwaves kill more people than any other natural hazard in Australia. Current literature on managing health risks of heatwaves highlights the importance of implementing urban planning measures, and engaging with vulnerable groups on a local level to better understand perceptions of risk and tailor health protection measures. This paper reviews arrangements to reduce heatwave health risks in South East Queensland in response to these themes. A literature search and document analysis, stakeholder interviews, and multi-stakeholder cross-sectoral workshops revealed that although heatwave management is not always considered by local government and disaster management stakeholders, many urban planning measures to minimize urban heat have been pursued. However, greater information from vulnerable groups is still needed to better inform heatwave management measures.

Background: Treatment for advanced pancreatic cancer is still very unsatisfactory. Treosulfan is an alkylating agent used for conventional, as well as high-dose chemotherapy regimens, whereby plasma concentrations over 500 μg/ml can be achieved. We investigated the effects of treosulfan on pancreatic cancer cell lines., Materials and Methods: Using Panc-1, MIA PaCa-2 and Capan-2 cell lines, we investigated the in vitro cytotoxicity of treosulfan-alone and in combination with gemcitabine, 5-fluorouracil or irradiation., Results: Treosulfan was potently cytotoxic against all pancreatic cancer cell lines at all concentrations (1-100 μg/ml). Combination of treosulfan and gemcitabine revealed strong synergistic effects independent of the sequence of drug administration. Similarly, synergism was observed with irradiation. Combination of treosulfan and 5-fluorouracil revealed antagonism., Conclusion: Treosulfan effectively kills pancreatic carcinoma cells in vitro and has synergistic activity in combination with gemcitabine and irradiation. These results warrant further investigation of treosulfan in the treatment of pancreatic cancer.

Background: Tumors may develop resistance to specific angiogenic inhibitors via activation of alternative pathways. Therefore, multiple angiogenic pathways should be targeted to achieve significant angiogenic blockade. In this study we investigated the effects of a combined application of the angiogenic inhibitors endostatin and tumstatin in a model of human glioblastoma multiforme., Results: Inhibitors released by stably transfected porcine aortic endothelial cells (PAE) showed anti-angiogenic activity in proliferation and wound-healing assays with endothelial cells (EC). Interestingly, combination of endostatin and tumstatin (ES + Tum) also reduced proliferation of glioma cells and additionally induced morphological changes and apoptosis in vitro. Microencapsulated PAE-cells producing these inhibitors were applied for local therapy in a subcutaneous glioblastoma model. When endostatin or tumstatin were applied separately, in vivo tumor growth was inhibited by 58% and 50%, respectively. Combined application of ES + Tum, in comparison, resulted in a significantly more pronounced inhibition of tumor growth (83%). cDNA microarrays of tumors treated with ES + Tum revealed an up-regulation of prolactin receptor (PRLR). ES + Tum-induced up-regulation of PRLR in glioma cells was also found in in vitro. Moreover, exogenous PRLR overexpression in vitro led to up-regulation of its ligand prolactin and increased proliferation suggesting a functional autocrine growth loop in these cells., Conclusion: Our data indicate that integrin-targeting factors endostatin and tumstatin act additively by inhibiting glioblastoma growth via reduction of vessel density but also directly by affecting proliferation and viability of tumor cells. Treatment with the ES + Tum-combination activates the PRLR pro-proliferative pathway in glioblastoma. Future work will show whether the prolactin signaling pathway represents an additional target to improve therapeutic strategies in this entity.

In recent years, the monoclonal epidermal growth factor receptor (EGFR)-targeting antibody cetuximab was introduced into systemic therapy of colorectal cancer and gained an established role in the treatment of this disease. Cetuximab was shown to be active as a single agent in chemorefractory metastatic disease as well as in combination with varying chemotherapies. Recently, randomized trials demonstrated the activity of cetuximab combinations in the first-line setting of metastatic colorectal cancer. Interestingly, the activity of cetuximab was restricted to patients with KRAS wildtype tumors, as was seen with panitumumab, another EGFR antibody. While 60%-70% of tumors harbor KRAS wildtype genes, 30%-40% of tumors express oncogenic KRAS with mutations in codons 12 and 13 causing constitutive activation of signaling cascades downstream of EGFR and resistance to EGFR blockade. Since proof of KRAS wildtype status became a prerequisite for cetuximab treatment, KRAS testing is being established throughout the world. Future trials will address the question which part of the KRAS wildtype cohort will benefit from EGFR inhibition and how to identify those patients. Additionally, new strategies for treatment of KRAS mutated tumors are strongly needed. Recent developments and future strategies will be summarized.

Background: CEACAM-1 is involved in intercellular adhesion and is expressed in a variety of human tissues. In cases of malignant transformation, a down-regulation or loss of CEACAM-1 has been shown. In contrast, CEACAM-1 is not expressed in normal lung tissue or melanocytes. It has been demonstrated that an expression in these tissues is associated with the development of metastatic disease. The aim of the present investigation was to analyze a possible association between the expression of CEACAM-1 in pulmonary adenocarcinomas and their lymph node and hematogenous metastatic cells., Patients and Methods: CEACAM-1 expression was immunhistochemically evaluated in primary tumors, lymph nodes and distant metastases of 96 patients with metastatic pulmonary adenocarcinoma who had undergone surgery between 1999 and 2002., Results: Expression of CEACAM-1 was shown in 78 out of 96 primary tumors (81.3%). A significant positive correlation was found between CEACAM-1 expression on cells of the primary tumor, lymph node metastases (p < 0.005) and hematogenous metastases (p = 0.03). CEACAM-1 expression did not correlate with stage, gender, grading or patients' age. Compared to patients with tumors not expressing CEACAM-1, patients with a CEACAM-1-expressing tumor had a shorter median overall survival (21 vs. 28 months) and progression-free survival (11.7 vs. 16.3 months)., Conclusion: CEACAM-1 is expressed in most primary pulmonary adenocarcinomas. This investigation demonstrates that its expression is preserved in lymph node and hematogenous metastases, indicating that its expression is of functional significance for both metastatic sites. These results support the prognostic relevance of the expression of CEACAM-1 in pulmonary adenocarcinoma.

Purpose: Angiogenesis and lymphangiogenesis are important steps in tumor growth and dissemination and are of prognostic importance in solid tumors. The determination of microvessel density (MVD) by immunohistology is subject to considerable variability between different laboratories and observers. We compared MVD determination by immunohistology and quantitative real-time PCR and correlated the results with clinical variables., Experimental Design: The expression of endothelial antigens vascular endothelial cadherin (CD144), P1H12 (CD146), tie-2, and VEGFR-2, and lymphatic endothelial markers VEGFR-3, Prox, and LYVE was assessed by quantitative PCR (qPCR) in primary surgical samples. The expression of angiogenetic growth factors VEGF-A, VEGF-C, VEGF-D, angiopoietin-1, and angiopoietin-2 was quantified by PCR and correlated with MVD and clinical variables., Results: The expression of endothelial antigens vascular endothelial cadherin (CD144), P1H12 (CD146), tie-2, and VEGFR-2 correlated with each other in 54 samples of primary esophageal cancer (P < 0.0001 for all comparisons). MVD determined immunohistologically by CD31 staining in a subgroup of 35 patients correlated significantly with the qPCR method. The expression of angiogenetic growth factors VEGF-A, VEGF-C, VEGF-D, angiopoietin-1, and angiopoietin-2 was significantly associated with MVD (P < 0.0001 for all comparisons). Analysis of the expression of lymphendothelial markers VEGFR-3, Prox, and LYVE revealed concordant results, indicating that quantification of lymphendothelial cells is possible by qPCR. The presence of lymph node metastasis on surgical specimens was significantly correlated with MVD (P < 0.003), VEGFR-2 (P < 0.048), and VEGF-C (P < 0.042) expression., Conclusions: These results indicate that quantification of MVD by qPCR in surgical samples of esophageal carcinoma yields similar results with immunohistology. Interestingly, the extent of angiogenesis and lymphangiogenesis was not related in individual tumor samples. Lymph node metastases could be predicted by MVD and VEGF-C expression.

Circulating endothelial cells (CECs) are present in peripheral blood and have been shown to contribute to normal and pathological neovascularization. Antiangiogenic molecules can inhibit neovascularization in tumors and other sites, but their effect on CECs has not yet been determined. We hypothesize that angiogenic factors will increase the number of CECs, and conversely, antiangiogenic treatment will reduce these numbers. Mice treated with high levels of vascular endothelial growth factor (VEGF) showed increased numbers of Flk-1-positive cells in peripheral blood and endothelial cell colonies compared with vehicle-treated controls. These changes were accompanied by increased bone marrow neovascularization. In contrast, mice that received VEGF and endostatin had significantly lower numbers of CECs and reduced bone marrow vascularization. Endostatin-induced apoptosis was probably responsible for the decreased number of CECs. Systemic delivery of a VEGF antagonist, soluble Flt-1, also inhibited the VEGF-induced increase in CECs. These results were further confirmed in a Tie2/LacZ mouse model, in which endostatin reduced the number of beta-galactosidase-expressing peripheral blood mononuclear cells. We propose that endothelial progenitor cells are a novel target for endostatin and suggest that the relative numbers of CECs can serve as a surrogate marker for the biological activity of antiangiogenic treatment.

Recent findings implied that the progression of hematologic malignancies, like that of solid tumors, is dependent on neovascularization. Recent studies on patients with acute myeloid leukemia (AML) showed increased levels of leukocyte-associated vascular endothelial growth factor (VEGF) and neovascularization of the bone marrow. Murine (32D, M1) and human (HEL, U937, and UKE-1) leukemic cell lines and freshly isolated leukemic cells were analyzed for the expression of VEGF and VEGF receptor mRNA. The expression of VEGF and VEGF receptors KDR and neuropilin-1 (NRP-1) was detected in these cells. In a murine chloroma model, delivery of VEGF(165) using microencapsulation technology resulted in enhanced tumor growth and vascularization, whereas treatment with a VEGF antagonist soluble NRP-1 (sNRP-1) inhibited tumor angiogenesis and growth. In a systemic leukemia model, survival of mice injected with adenovirus (Ad) encoding for Fc-sNRP-1 (sNRP-1 dimer) was significantly prolonged as compared with mice injected with Ad-LacZ. Further analyses showed a reduction in circulating leukemic cells and infiltration of liver and spleen as well as bone marrow neovascularization and cellularity. Taken together, these results demonstrate that angiogenic factors such as VEGF promote AML progression in vivo. The use of VEGF antagonists as an antiangiogenesis approach offers a potential treatment for AML. Finally, our novel in vivo drug delivery model may be useful for testing the activities of other peptide antiangiogenic factors.

Nuclear transplantation (therapeutic cloning) could theoretically provide a limitless source of cells for regenerative therapy. Although the cloned cells would carry the nuclear genome of the patient, the presence of mitochondria inherited from the recipient oocyte raises questions about the histocompatibility of the resulting cells. In this study, we created bioengineered tissues from cardiac, skeletal muscle, and renal cells cloned from adult bovine fibroblasts. Long-term viability was demonstrated after transplantation of the grafts into the nuclear donor animals. Reverse transcription-PCR (RT-PCR) and western blot analysis confirmed that the cloned tissues expressed tissue-specific mRNA and proteins while expressing a different mitochondrial DNA (mtDNA) haplotype. In addition to creating skeletal muscle and cardiac "patches", nuclear transplantation was used to generate functioning renal units that produced urinelike fluid and demonstrated unidirectional secretion and concentration of urea nitrogen and creatinine. Examination of the explanted renal devices revealed formation of organized glomeruli- and tubule-like structures. Delayed-type hypersensitivity (DTH) testing in vivo and Elispot analysis in vitro suggested that there was no rejection response to the cloned renal cells. The ability to generate histocompatible cells using cloning techniques addresses one of the major challenges in transplantation medicine.

Recent findings support the hypothesis that the CD34(+)-cell population in bone marrow and peripheral blood contains hematopoietic and endothelial progenitor and stem cells. In this study, we report that human AC133(+) cells from granulocyte colony-stimulating factor-mobilized peripheral blood have the capacity to differentiate into endothelial cells (ECs). When cultured in the presence of vascular endothelial growth factor (VEGF) and the novel cytokine stem cell growth factor (SCGF), AC133(+) progenitors generate both adherent and proliferating nonadherent cells. Phenotypic analysis of the cells within the adherent population reveals that the majority display endothelial features, including the expression of KDR, Tie-2, Ulex europaeus agglutinin-1, and von Willebrand factor. Electron microscopic studies of these cells show structures compatible with Weibel-Palade bodies that are found exclusively in vascular endothelium. AC133-derived nonadherent cells give rise to both hematopoietic and endothelial colonies in semisolid medium. On transfer to fresh liquid culture with VEGF and SCGF, nonadherent cells again produce an adherent and a nonadherent population. In mice with severe combined immunodeficiency, AC133-derived cells form new blood vessels in vivo when injected subcutaneously together with A549 lung cancer cells. These data indicate that the AC133(+)-cell population consists of progenitor and stem cells not only with hematopoietic potential but also with the capacity to differentiate into ECs. Whether these hematopoietic and endothelial progenitors develop from a common precursor, the hemangioblast will be studied at the single-cell level.