Time filter

Source Type

Rohrl C.,Medical University of Vienna | Kaindl U.,Medical University of Vienna | Kaindl U.,Childrens Cancer Research Institute CCRI | Koneczny I.,Medical University of Vienna | And 4 more authors.
Journal of Cancer Research and Clinical Oncology | Year: 2011

Background: Peroxisome-proliferator-activated receptors (PPARs) are nuclear receptors for fatty acids and their derivatives. PPAR subtypes PPARγ and PPARβ/δ are suspected to modulate cancer development in the colon, but their exact role is still discussed controversially. Methods: The present study investigated the impact of PPARγ and PPARβ/δ on vascular endothelial growth factor (VEGF) and cyclooxygenase 2 (COX-2) expressions induced by synthetic and physiological agonists in the colorectal tumor cell lines SW480 and HT29 using reporter gene assays, qRT-PCR and ELISA. Results: Activation of both PPARγ and PPARβ/δ induced expression of VEGF mRNA and protein in a PPAR-dependent way. The PPARγ agonists ciglitazone and PGJ2 were the most effective inducers with up to ninefold and threefold increases in VEGF mRNA in SW480 and HT29 cultures, respectively. VEGF secretion was doubled in both cell lines. The PPARβ/δ agonists GW501516 and PGI2 caused stimulations of only 1.5-fold in both cell lines. In addition, all PPAR agonists induced COX-2 mRNA and secretion of the COX-2 product PGE2 in HT29 cells. However, this effect was not blocked by knock-down of PPAR expression nor was it essential for VEGF expression as shown by the lack of effect of the COX-2 inhibitor SC236. Conclusion: In summary, our results identify both PPARγ and PPARβ/δ as an alternative COX-independent mechanism of VEGF induction in colorectal tumor cells. © 2010 Springer-Verlag. Source

Borgmann-Staudt A.,Charite - Medical University of Berlin | Rendtorff R.,Charite - Medical University of Berlin | Reinmuth S.,Charite - Medical University of Berlin | Hohmann C.,Charite - Medical University of Berlin | And 8 more authors.
Bone Marrow Transplantation | Year: 2012

Infertility is a major late effect in patients receiving haematopoietic stem cell transplantation (HSCT). The aim of this study was to determine the proportion of patients having fertility impairment after allogeneic HSCT in childhood/adolescence and to identify the potential risk factors. Treatment and fertility data of paediatric patients with malignant and non-malignant diseases treated with allogeneic HSCT between 2000 and 2005 were collected from seven European centres. Data were obtained for 138 female and 206 male patients after a median follow-up of 6 years (range 3-12). The patients median age was ≥13 years (range 4-28) at the time of HSCT and 19 (range 12-35) years at the time of the enquiry. Seven children were born to the overall group, all at term and healthy. Fertility impairment was suspected in 69% males and 83% females. Start of treatment at age 13 years was a risk factor in females (odds ratio (OR) 4.7; 95% confidence interval (CI), 1.5 to 14.9), whereas pre-pubertal therapy was a risk factor in males (OR 0.4; 95% CI, 0.2 to 0.8). The major treatment-related risk factors were BU in females (OR 47.4; 95% CI, 5.4 to 418.1) and TBI in males (OR 7.7; 95% CI, 2.3 to 25.4). In light of the significant proportion of HSCT patients reviewed with impaired fertility, fertility conservation procedures should be considered for all patients undergoing HSCT, particularly those receiving TBI or BU-based preparative regimens. © 2012 Macmillan Publishers Limited. All rights reserved. Source

Storlazzi C.T.,University of Bari | Lonoce A.,University of Bari | Guastadisegni M.C.,University of Bari | Trombetta D.,University of Bari | And 12 more authors.
Genome Research | Year: 2010

Double minutes (dmin) and homogeneously staining regions (hsr) are the cytogenetic hallmarks of genomic amplification in cancer. Different mechanisms have been proposed to explain their genesis. Recently, our group showed that the MYC-containing dmin in leukemia cases arise by excision and amplification (episome model). In the present paper we investigated 10 cell lines from solid tumors showing MYCN amplification as dmin or hsr. Particularly revealing results were provided by the two subclones of the neuroblastoma cell line STA-NB-10, one showing dmin-only and the second hsr-only amplification. Both subclones showed a deletion, at 2p24.3, whose extension matched the amplicon extension. Additionally, the amplicon structure of the dmin and hsr forms was identical. This strongly argues that the episome model, already demonstrated in leukemias, applies to solid tumors as well, and that dmin and hsr are two faces of the same coin. The organization of the duplicated segments varied from very simple (no apparent changes from the normal sequence) to very complex. MYCN was always overexpressed (significantly overexpressed in three cases). The fusion junctions, always mediated by nonhomologous end joining, occasionally juxtaposed truncated genes in the same transcriptional orientation. Fusion transcripts involving NBAS (also known as NAG), FAM49A, BC035112 (also known as NCRNA00276), and SMC6 genes were indeed detected, although their role in the context of the tumor is not clear. © 2010 by Cold Spring Harbor Laboratory Press. Source

Lehner M.,Friedrich - Alexander - University, Erlangen - Nuremberg | Gotz G.,Friedrich - Alexander - University, Erlangen - Nuremberg | Proff J.,Friedrich - Alexander - University, Erlangen - Nuremberg | Schaft N.,Friedrich - Alexander - University, Erlangen - Nuremberg | And 10 more authors.
PLoS ONE | Year: 2012

We explored the possibility to target Ewing's sarcoma family of tumors (ESFT) by redirecting T cells. To this aim, we considered NKG2D-ligands (NKG2D-Ls) as possible target antigens. Detailed analysis of the expression of MICA, MICB, ULBP-1, -2, and -3 in fourteen ESFT cell lines revealed consistent expression of at least one NKG2D-L. Thus, for redirecting T cells, we fused a CD3ζ/CD28-derived signaling domain to the ectodomain of NKG2D, however, opposite transmembrane orientation of this signaling domain and NKG2D required inverse orientation fusion of either of them. We hypothesized that the particularly located C-terminus of the NKG2D ectodomain should allow reengineering of the membrane anchoring from a native N-terminal to an artificial C-terminal linkage. Indeed, the resulting chimeric NKG2D receptor (chNKG2D) was functional and efficiently mediated ESFT cell death triggered by activated T cells. Notably, ESFT cells with even low NKG2D-L expression were killed by CD8 pos and also CD4 pos cells. Both, mRNA transfection and lentiviral transduction resulted in high level surface expression of chNKG2D. However, upon target-cell recognition receptor surface levels were maintained by tranfected RNA only during the first couple of hours after transfection. Later, target-cell contact resulted in strong and irreversible receptor down-modulation, whereas lentivirally mediated expression of chNKG2D remained constant under these conditions. Together, our study defines NKG2D-Ls as targets for a CAR-mediated T cell based immunotherapy of ESFT. A comparison of two different methods of gene transfer reveals strong differences in the susceptibility to ligand-induced receptor down-modulation with possible implications for the applicability of RNA transfection. © 2012 Lehner et al. Source

Aryee D.N.T.,Childrens Cancer Research Institute CCRI | Aryee D.N.T.,Medical University of Vienna | Niedan S.,Childrens Cancer Research Institute CCRI | Ban J.,Childrens Cancer Research Institute CCRI | And 6 more authors.
British Journal of Cancer | Year: 2013

Background:Though p53 mutations are rare in ES, there is a strong indication that p53 mutant tumours form a particularly bad prognostic group. As such, novel treatment strategies are warranted that would specifically target and eradicate tumour cells containing mutant p53 in this subset of ES patients.Methods:PRIMA-1 Met, also known as APR-246, is a small organic molecule that has been shown to restore tumour-suppressor function primarily to mutant p53 and also to induce cell death in various cancer types. In this study, we interrogated the ability of APR-246 to induce apoptosis and inhibit tumour growth in ES cells with different p53 mutations.Results:APR-246 variably induced apoptosis, associated with Noxa, Puma or p21 WAF1 upregulation, in both mutant and wild-type p53 harbouring cells. The apoptosis-inducing capability of APR-246 was markedly reduced in ES cell lines transfected with p53 siRNA. Three ES cell lines established from the same patient at different stages of the disease and two cell lines of different patients with identical p53 mutations all exhibited different sensitivities to APR-246, indicating cellular context dependency. Comparative transcriptome analysis on the three cell lines established from the same patient identified differential expression levels of several TP53 and apoptosis-associated genes such as APOL6, PENK, PCDH7 and MST4 in the APR-246-sensitive cell line relative to the less APR-246-sensitive cell lines.Conclusion:This is the first study reporting the biological response of Ewing sarcoma cells to APR-246 exposure and shows gross variability in responses. Our study also proposes candidate genes whose expression might be associated with ES cells' sensitivity to APR-246. With APR-246 currently in early-phase clinical trials, our findings call for caution in considering it as a potential adjuvant to conventional ES-specific chemotherapeutics. © 2013 Cancer Research UK. All rights reserved. Source

Discover hidden collaborations