Time filter

Source Type

Heckmann D.,German Cancer Research Center | Heckmann D.,University of Heidelberg | Maier P.,University of Mannheim | Laufs S.,German Cancer Research Center | And 10 more authors.
Clinical Cancer Research

Purpose: In colorectal cancer, increased expression of the CXC chemokine receptor 4 (CXCR4) has been shown to provoke metastatic disease due to the interaction with its ligand stromal cell-derived factor-1 (SDF-1). Recently, a second SDF-1 receptor, CXCR7, was found to enhance tumor growth in solid tumors. Albeit signaling cascades via SDF-1/CXCR4 have been intensively studied, the significance of the SDF-1/CXCR7-induced intracellular communication triggering malignancy is still only marginally understood. Experimental Design: In tumor tissue of 52 patients with colorectal cancer, we observed that expression of CXCR7 and CXCR4 increased with tumor stage and tumor size. Asking whether activation of CXCR4 or CXCR7 might result in a similar expression pattern, we performed microarray expression analyses using lentivirally CXCR4- and/or CXCR7-overexpressing SW480 colon cancer cell lines with and without stimulation by SDF-1α. Results: Gene regulation via SDF-1α/CXCR4 and SDF-1α/CXCR7 was completely different and partly antidromic. Differentially regulated genes were assigned by gene ontology to migration, proliferation, and lipid metabolic processes. Expressions of AKR1C3, AXL, C5, IGFBP7, IL24, RRAS, and TNNC1 were confirmed by quantitative real-time PCR. Using the in silico gene set enrichment analysis, we showed that expressions of miR-217 and miR-218 were increased in CXCR4 and reduced in CXCR7 cells after stimulation with SDF-1α. Functionally, exposure to SDF-1α increased invasiveness of CXCR4 and CXCR7 cells, AXL knockdown hampered invasion. Compared with controls, CXCR4 cells showed increased sensitivity against 5-FU, whereas CXCR7 cells were more chemoresistant. Conclusions: These opposing results for CXCR4- or CXCR7-overexpressing colon carcinoma cells demand an unexpected attention in the clinical application of chemokine receptor antagonists such as plerixafor. © 2014 American Association for Cancer Research. Source

Kamioner D.,AFSOS and Hopital Prive de lOuest Parisien | Fruehauf S.,Center for Tumor Diagnostics and Therapy | Maloisel F.,Clinique Saint Anne | Cals L.,CHRU de Besancon | And 2 more authors.
BMC Cancer

Background: Nivestim™ (filgrastim) is a follow-on biologic agent licensed in the EU for the treatment of neutropenia and febrile neutropenia induced by myelosuppressive chemotherapy. Nivestim™ has been studied in phase 2 and 3 clinical trials where its efficacy and safety was found to be similar to its reference product, Neupogen®. Follow-on biologics continue to be scrutinised for safety. We present a design for two observational phase IV studies that are evaluating the safety profile of Nivestim™ for the prevention and treatment of febrile neutropenia (FN) in patients treated with cytotoxic chemotherapy in general clinical practice.Methods/Design: The NEXT (Tolérance de Nivestim chez les patiEnts traités par une chimiothérapie anticancéreuse cytotoXique en praTique courante) and VENICE (VErträglichkeit von NIvestim unter zytotoxischer Chemotherapie in der Behandlung malinger Erkrankungen) trials are multicentre, prospective, longitudinal, observational studies evaluating the safety profile of Nivestim™ in 'real-world' clinical practice. Inclusion criteria include patients undergoing cytotoxic chemotherapy for malignancy and receiving Nivestim as primary or secondary prophylaxis (NEXT and VENICE), or as treatment for ongoing FN (NEXT only). In accordance with European Union pharmacovigilance guidelines, the primary objective is to evaluate the safety of Nivestim™ by gathering data on adverse events in all system organ classes. Secondary objectives include obtaining information on patient characteristics, efficacy of Nivestim™ therapy (including chemotherapy dose intensity), patterns of use of Nivestim™, and physician knowledge regarding filgrastim prescription and the reasons for choosing Nivestim™. Data will be gathered at three visits: 1. At the initial inclusion visit, 2. At a 1-month follow-up visit, and 3. At the end of chemotherapy. Recruitment for VENICE commenced in July 2011 and in November 2011 for NEXT. VENICE completed recruitment in July 2013 with 407 patients, and NEXT in September 2013 with 2123 patients. Last patient, last visit for each study will be December 2013 and March 2014 respectively.Discussion: The NEXT and VENICE studies will provide long-term safety, efficacy and practice pattern data in patients receiving Nivestim™ to support myelosuppressive chemotherapy in real world clinical practice. These data will improve our understanding of the performance of Nivestim™ in patients encountered in the general patient population. Trial registration: NEXT NCT01574235, VENICE NCT01627990. © 2013 Kamioner et al.; licensee BioMed Central Ltd. Source

Fruehauf S.,Center for Tumor Diagnostics and Therapy | Tricot G.,University of Utah
Biology of Blood and Marrow Transplantation

Autologous and allogeneic hematopoietic stem cell transplantation (HSCT) are considered the standard of care for many malignancies, including lymphoma, myeloma, and some leukemias. In many cases, mobilized peripheral blood has become the preferred source of hematopoietic stem cells. The efficacy of different mobilization regimens and transplantation outcomes based on cell doses has been well studied; however, the characteristics of the stem cell graft may be of equal importance with respect to patient outcomes following autologous or allogeneic HSCT. This review summarizes available preclinical and clinical data for bone marrow and mobilized peripheral blood HSCT characteristics, defined as the cell types found in the graft as well as their gene expression profiles. It also explores how graft characteristics can affect bone marrow homing, engraftment, immune reconstitution, and other posttransplantation outcomes in both the allogeneic and autologous HSCT settings. © 2010 American Society for Blood and Marrow Transplantation. Source

Jeltsch K.S.,German Cancer Research Center | Radke T.F.,Cell Therapeutics | Laufs S.,German Cancer Research Center | Giordano F.A.,German Cancer Research Center | And 8 more authors.

Background aims: Transplantation of allogeneic hematopoietic stem cells (HSC) within the framework of hematologic oncology or inherited diseases may be associated with complications such as engraftment failure and long-term pancytopenia. HSC engraftment can be improved, for example by co-transplantation with mesenchymal stem cells (MSC). Recently, a new multipotent MSC line from umbilical cord blood, unrestricted somatic stem cells (USSC), has been described. It was demonstrated that USSC significantly support proliferation of HSC in an in vitro feeder layer assay. Methods. A NOD/SCID mouse model was used to assess the effect of USSC on co-transplanted CD34+ cells and look for the fate of transplanted USSC. The migration potential of USSC was studied in a Boyden chamber migration assay and in vivo. Quantitative real-time polymerase chain reaction (qRT-PCR) for CXCR4, CD44, LFA1, CD62L, VLA4, RAC2, VLA5A and RAC1 were performed. NMR1 nu/nu mice were used for a tumorigenicity test. Results. After 4 weeks, homing of human cells (CD45+) to the bone marrow of NOD/SCID mice was significantly increased in mice co-transplanted with CD34+ cells and USSC (median 30.9%, range 7-50%) compared with the CD34+ cell-only control group (median 5.9%, range 3-10%; P = 0.004). Homing of USSC could not be shown in the bone marrow. A cell-cell contact was not required for the graft enhancing effect of USSC. An in vivo tumorigenicity assay showed no tumorigenic potential of USSC. Conclusions. This pre-clinical study clearly shows that USSC have an enhancing effect on engraftment of human CD34+ cells. USSC are a safe graft adjunct. © 2011 Informa Healthcare. Source

Maier P.,German Cancer Research Center | Maier P.,University of Heidelberg | Spier I.,German Cancer Research Center | Laufs S.,German Cancer Research Center | And 5 more authors.
Gene Therapy

Myelotoxicity is a dose-limiting effect of many chemotherapeutic regimens. Thus, there is great interest in protecting human hematopoietic stem cells by the transfer of drug resistance genes. The main focus of this study was the simultaneous overexpression of multidrug resistance 1 (MDR1) and the O 6-benzylguanine (O 6-BG)-resistant mutant MGMT P140K (O 6-methylguanine-DNA methyltransferase) with a bicistronic lentiviral vector (HR′SIN-MDR1-IRES- MGMT P140K), with regard to the capability to convey chemoprotection in the leukemia cell line, HL60, and human hematopoietic stem cells (CD34). Combination therapy with O 6-BG/1-(2-chloroethyl)-3-(4-amino-2-methylpyrimidine-5-yl) methyl-1-nitrosourea) (ACNU) plus paclitaxel showed a significant survival advantage of HL60 cells transduced with this combination vector. In CD34 cells, monotherapy with O 6-BG/temozolomide (TMZ) resulted in an increased percentage of MGMT-positive cells (vs untreated cells) after transduction with HR′SIN-MDR1-IRES-MGMT P140K (28.3%). For combination therapy with O 6-BG/temozolomide plus paclitaxel the increase was higher with the combination vector (52.8%) than with a vector expressing MGMT P140K solely (29.1%). With regard to MDR1-positive cells the protective effect of the combination vector (88.5%) was comparable to the single vector HR′SIN-MDR1 (90.0%) for monotherapy with paclitaxel and superior for combination therapy with O 6-BG/temozolomide plus paclitaxel (84.6 vs 69.7%). In conclusion, the combination vector presents simultaneous protective effects of two drug-resistance genes, offering an opportunity to increase the cancer therapeutic index. © 2010 Macmillan Publishers Limited All rights reserved. Source

Discover hidden collaborations