Dittmann, Kai

[["dc.bibliographiccitation.firstpage","1587"],["dc.bibliographiccitation.issue","10"],["dc.bibliographiccitation.journal","Cancer Immunology Immunotherapy"],["dc.bibliographiccitation.lastpage","1597"],["dc.bibliographiccitation.volume","62"],["dc.contributor.author","Koenig, Simone"],["dc.contributor.author","Regen, Tommy"],["dc.contributor.author","Dittmann, Kai"],["dc.contributor.author","Engelke, Michael"],["dc.contributor.author","Wienands, Juergen"],["dc.contributor.author","Schwendener, Reto"],["dc.contributor.author","Hanisch, Uwe-Karsten"],["dc.contributor.author","Pukrop, Tobias"],["dc.contributor.author","Hahn, Heidi"],["dc.date.accessioned","2018-11-07T09:19:32Z"],["dc.date.available","2018-11-07T09:19:32Z"],["dc.date.issued","2013"],["dc.description.abstract","Liposomes are frequently used in cancer therapy to encapsulate and apply anticancer drugs. Here, we show that a systemic treatment of mice bearing skin tumors with empty phosphatidylcholine liposomes (PCL) resulted in inhibition of tumor growth, which was similar to that observed with the synthetic bacterial lipoprotein and TLR1/2 agonist Pam(3)CSK(4) (BLP). Both compounds led to a substantial decrease of macrophages in spleen and in the tumor-bearing skin. Furthermore, both treatments induced the expression of typical macrophage markers in the tumor-bearing tissue. As expected, BLP induced the expression of the M1 marker genes Cxcl10 and iNOS, whereas PCL, besides inducing iNOS, also increased the M2 marker genes Arg1 and Trem2. In vitro experiments demonstrated that neither PCL nor BLP influenced proliferation or survival of tumor cells, whereas both compounds inhibited proliferation and survival and increased the migratory capacity of bone marrow-derived macrophages (BMDM). However, in contrast to BLP, PCL did not activate cytokine secretion and induced a different BMDM phenotype. Together, the data suggest that similar to BLP, PCL induce an antitumor response by influencing the tumor microenvironment, in particular by functional alterations of macrophages, however, in a distinct manner from those induced by BLP."],["dc.description.sponsorship","DFG [FOR942 HA 2197/5-2]"],["dc.identifier.doi","10.1007/s00262-013-1444-4"],["dc.identifier.isi","000325008800005"],["dc.identifier.pmid","23917775"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/28662"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Springer"],["dc.relation.issn","0340-7004"],["dc.title","Empty liposomes induce antitumoral effects associated with macrophage responses distinct from those of the TLR1/2 agonist Pam(3)CSK(4) (BLP)"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","e93555"],["dc.bibliographiccitation.issue","4"],["dc.bibliographiccitation.journal","PLoS ONE"],["dc.bibliographiccitation.volume","9"],["dc.contributor.author","Koenig, Simone"],["dc.contributor.author","Nitzki, Frauke"],["dc.contributor.author","Uhmann, Anja"],["dc.contributor.author","Dittmann, Kai"],["dc.contributor.author","Theiss-Suennemann, Jennifer"],["dc.contributor.author","Herrmann, Markus"],["dc.contributor.author","Reichardt, Holger Michael"],["dc.contributor.author","Schwendener, Reto"],["dc.contributor.author","Pukrop, Tobias"],["dc.contributor.author","Schulz-Schaeffer, Walter J."],["dc.contributor.author","Hahn, Heidi"],["dc.date.accessioned","2018-11-07T09:41:53Z"],["dc.date.available","2018-11-07T09:41:53Z"],["dc.date.issued","2014"],["dc.description.abstract","Basal cell carcinoma (BCC) belongs to the group of non-melanoma skin tumors and is the most common tumor in the western world. BCC arises due to mutations in the tumor suppressor gene Patched1 (Ptch). Analysis of the conditional Ptch knockout mouse model for BCC reveals that macrophages and dendritic cells (DC) of the skin play an important role in BCC growth restraining processes. This is based on the observation that a clodronate-liposome mediated depletion of these cells in the tumor-bearing skin results in significant BCC enlargement. The depletion of these cells does not modulate Ki67 or K10 expression, but is accompanied by a decrease in collagen-producing cells in the tumor stroma. Together, the data suggest that cutaneous macrophages and DC in the tumor microenvironment exert an antitumor effect on BCC."],["dc.description.sponsorship","Deutsche Forschungsgemeinschaft [FOR942 HA 2197/5-2]"],["dc.identifier.doi","10.1371/journal.pone.0093555"],["dc.identifier.isi","000334101100104"],["dc.identifier.pmid","24691432"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/10067"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/33833"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Public Library Science"],["dc.relation.issn","1932-6203"],["dc.rights","CC BY 4.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/4.0"],["dc.title","Depletion of Cutaneous Macrophages and Dendritic Cells Promotes Growth of Basal Cell Carcinoma in Mice"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.issue","5"],["dc.bibliographiccitation.journal","The Journal of Immunology"],["dc.bibliographiccitation.volume","183"],["dc.contributor.author","Uhmann, Anja"],["dc.contributor.author","Dittmann, Kai"],["dc.contributor.author","Wienands, Juergen"],["dc.contributor.author","Hahn, Heidi"],["dc.date.accessioned","2018-11-07T11:25:03Z"],["dc.date.available","2018-11-07T11:25:03Z"],["dc.date.issued","2009"],["dc.format.extent","2891"],["dc.identifier.doi","10.4049/jimmunol.0990063"],["dc.identifier.isi","000269391400001"],["dc.identifier.pmid","19696426"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/56544"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Amer Assoc Immunologists"],["dc.relation.issn","0022-1767"],["dc.title","Comment on \"Direct Hematological Toxicity and Illegitimate Chromosomal Recombination Caused by the Systemic Activation of CreER(T2)\""],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.subtype","letter_note"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","3259"],["dc.bibliographiccitation.issue","2"],["dc.bibliographiccitation.journal","Oncotarget"],["dc.bibliographiccitation.lastpage","3273"],["dc.bibliographiccitation.volume","8"],["dc.contributor.author","Draeger, Julia"],["dc.contributor.author","Simon-Keller, Katja"],["dc.contributor.author","Pukrop, Tobias"],["dc.contributor.author","Klemm, Florian"],["dc.contributor.author","Wilting, Joerg"],["dc.contributor.author","Sticht, Carsten"],["dc.contributor.author","Dittmann, Kai"],["dc.contributor.author","Schulz, Matthias"],["dc.contributor.author","Leuschner, Ivo"],["dc.contributor.author","Marx, Alexander"],["dc.contributor.author","Hahn, Heidi"],["dc.date.accessioned","2018-11-07T10:28:26Z"],["dc.date.available","2018-11-07T10:28:26Z"],["dc.date.issued","2017"],["dc.description.abstract","Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma in children and show characteristics of skeletal muscle differentiation. The two major RMS subtypes in children are alveolar (ARMS) and embryonal RMS (ERMS). We demonstrate that approximately 50% of ARMS and ERMS overexpress the LEF1/TCF transcription factor LEF1 when compared to normal skeletal muscle and that LEF1 can restrain aggressiveness especially of ARMS cells. LEF1 knockdown experiments in cell lines reveal that depending on the cellular context, LEF1 can induce pro-apoptotic signals. LEF1 can also suppress proliferation, migration and invasiveness of RMS cells both in vitro and in vivo. Furthermore, LEF1 can induce myodifferentiation of the tumor cells. This may involve regulation of other LEF1/TCF factors i.e. TCF1, whereas beta-catenin activity plays a subordinate role. Together these data suggest that LEF1 rather has tumor suppressive functions and attenuates aggressiveness in a subset of RMS."],["dc.description.sponsorship","Open-Access-Publikationsfonds 2016"],["dc.identifier.doi","10.18632/oncotarget.13887"],["dc.identifier.isi","000391506300114"],["dc.identifier.pmid","27965462"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/14022"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/43418"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","PUB_WoS_Import"],["dc.publisher","Impact Journals Llc"],["dc.relation.issn","1949-2553"],["dc.rights","CC BY 3.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/3.0"],["dc.title","LEF1 reduces tumor progression and induces myodifferentiation in a subset of rhabdomyosarcoma"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","19614"],["dc.bibliographiccitation.issue","32"],["dc.bibliographiccitation.journal","Journal of Biological Chemistry"],["dc.bibliographiccitation.lastpage","19628"],["dc.bibliographiccitation.volume","290"],["dc.contributor.author","Linder, Benedikt"],["dc.contributor.author","Weber, Susanne"],["dc.contributor.author","Dittmann, Kai"],["dc.contributor.author","Adamski, Jerzy"],["dc.contributor.author","Hahn, Heidi"],["dc.contributor.author","Uhmann, Anja"],["dc.date.accessioned","2018-11-07T09:53:20Z"],["dc.date.available","2018-11-07T09:53:20Z"],["dc.date.issued","2015"],["dc.description.abstract","The Patched1 (Ptch)-mediated inhibition of Smoothened (Smo) is still an open question. However, a direct Ptch/Smo interaction has been excluded, Smo modulators were identified, but the endogenous signal transmitting molecule remains undiscovered. Here, we demonstrate that calcitriol, the hormonally active form of vitamin D-3, is an excellent candidate for transmission of Ptch/Smo interaction. Our study reveals that Ptch expression is sufficient to release calcitriol from the cell and that calcitriol inhibits Smo action and ciliary translocation by acting on a site distinct from the 7-transmembrane domain or the cysteine-rich domain. Moreover calcitriol strongly synergizes with itraconazole (ITZ) in Smo inhibition, which did not result from elevated calcitriol bioavailability due to ITZ-mediated 24-hydroxylase inhibition but rather from a direct interaction of the compounds at the level of Smo. Together, we suggest that calcitriol represents a possible endogenous transmitter of Ptch/Smo interaction. Moreover calcitriol or calcitriol derivatives combined with ITZ might be a treatment option of Hedgehog-associated cancers."],["dc.description.sponsorship","Deutsche Forschungsgemeinschaft [UH 228/2-1, UH228/2-2]"],["dc.identifier.doi","10.1074/jbc.M115.646141"],["dc.identifier.isi","000359364600023"],["dc.identifier.pmid","26126827"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/36311"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Amer Soc Biochemistry Molecular Biology Inc"],["dc.relation.issn","1083-351X"],["dc.relation.issn","0021-9258"],["dc.title","A Functional and Putative Physiological Role of Calcitriol in Patched1/Smoothened Interaction"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","396"],["dc.bibliographiccitation.journal","Frontiers in Oncology"],["dc.bibliographiccitation.volume","8"],["dc.contributor.author","Geyer, Natalie"],["dc.contributor.author","Ridzewski, Rosalie"],["dc.contributor.author","Bauer, Julia"],["dc.contributor.author","Kuzyakova, Maria"],["dc.contributor.author","Dittmann, Kai"],["dc.contributor.author","Dullin, Christian"],["dc.contributor.author","Rosenberger, Albert"],["dc.contributor.author","Schildhaus, Hans-Ulrich"],["dc.contributor.author","Uhmann, Anja"],["dc.contributor.author","Fulda, Simone"],["dc.contributor.author","Hahn, Heidi"],["dc.date.accessioned","2019-07-09T11:50:33Z"],["dc.date.available","2019-07-09T11:50:33Z"],["dc.date.issued","2018"],["dc.description.abstract","Rhabdomyosarcoma (RMS) is the most common pediatric soft tissue sarcoma with poor prognosis. RMS frequently show Hedgehog (HH) pathway activity, which is predominantly seen in the embryonal subtype (ERMS). They also show activation of Phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K) signaling. Here we compared the therapeutic effectiveness and the impact on HH target gene expression of Smoothened (SMO) antagonists with those of the PI3K inhibitor pictilisib in ERMS with and without mutations in the HH receptor Patched1 (PTCH). Our data demonstrate that growth of ERMS showing canonical Hh signaling activity due to Ptch germline mutations is efficiently reduced by SMO antagonists. This goes along with strong downregulation of the Hh target Gli1. Likewise Ptch mutant tumors are highly responsive toward the PI3K inhibitor pictilisib, which involves modulation of AKT and caspase activity. Pictilisib also modulates Hh target gene expression, which, however, is rather not correlated with its antitumoral effects. In contrast, sporadic ERMS, which usually express HH target genes without having PTCH mutation, apparently lack canonical HH signaling activity. Thus, stimulation by Sonic HE (SHH) or SAG (Smoothened agonist) or inhibition by SMO antagonists do not modulate HH target gene expression. In addition, SMO antagonists do not provoke efficient anticancer effects and rather exert off-target effects. In contrast, pictilisib and other PI3K/AKT/mTOR inhibitors potently inhibit cellular growth. They also efficiently inhibit HH target gene expression. However, of whether this is correlated with their antitumoral effects it is not clear. Together, these data suggest that PI3K inhibitors are a good and reliable therapeutic option for all ERMS, whereas SMO inhibitors might only be beneficial for ERMS driven by PTCH mutations."],["dc.identifier.doi","10.3389/fonc.2018.00396"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/15965"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/59798"],["dc.language.iso","en"],["dc.subject.ddc","610"],["dc.title","Different Response of Ptch Mutant and Ptch Wildtype Rhabdomyosarcoma Toward SMO and PI3K Inhibitors"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","134"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Gastroenterology"],["dc.bibliographiccitation.lastpage","U256"],["dc.bibliographiccitation.volume","144"],["dc.contributor.author","Pelczar, Penelope"],["dc.contributor.author","Zibat, Arne"],["dc.contributor.author","van Dop, Willemijn A."],["dc.contributor.author","Heijmans, Jarom"],["dc.contributor.author","Bleckmann, Annalen"],["dc.contributor.author","Gruber, Wolfgang"],["dc.contributor.author","Nitzki, Frauke"],["dc.contributor.author","Uhmann, Anja"],["dc.contributor.author","Guijarro, Maria V."],["dc.contributor.author","Hernando, Eva"],["dc.contributor.author","Dittmann, Kai"],["dc.contributor.author","Wienands, Juergen"],["dc.contributor.author","Dressel, Ralf"],["dc.contributor.author","Wojnowski, Leszek"],["dc.contributor.author","Binder, Claudia"],["dc.contributor.author","Taguchi, Takahiro"],["dc.contributor.author","Beißbarth, Tim"],["dc.contributor.author","Hogendoorn, Pancras Cornelis Wilhelmus"],["dc.contributor.author","Antonescu, Cristina R."],["dc.contributor.author","Rubin, Brian P."],["dc.contributor.author","Schulz-Schaeffer, Walter Joachim"],["dc.contributor.author","Aberger, Fritz"],["dc.contributor.author","van den Brink, Gijs R."],["dc.contributor.author","Hahn, Heidi Eva"],["dc.date.accessioned","2018-11-07T09:30:42Z"],["dc.date.available","2018-11-07T09:30:42Z"],["dc.date.issued","2013"],["dc.description.abstract","BACKGROUND & AIMS: A fraction of gastrointestinal stromal tumor (GIST) cells overexpress the platelet-derived growth factor receptor (PDGFR) A, although most overexpress KIT. It is not known if this is because these receptor tyrosine kinases have complementary oncogenic potential, or because of heterogeneity in the cellular origin of GIST. Little also is known about why Hedgehog (HH) signaling is activated in some GIST. HH binds to and inactivates the receptor protein patched homolog (PTCH). METHODS: Ptch was conditionally inactivated in mice (to achieve constitutive HH signaling) using a Cre recombinase regulated by the lysozyme M promoter. Cre-expressing cells were traced using R26R-LacZ reporter mice. Tumors were characterized by in situ hybridization, immunohistochemistry, immunoblot, and quantitative reverse-transcriptase polymerase chain reaction analyses. Cell transformation was assessed by soft agar assay. RESULTS: Loss of Ptch from lysozyme M-expressing cells resulted in the development of tumors of GIST-like localization and histology; these were reduced when mice were given imatinib, a drug that targets KIT and PDGFRA. The Hh signaling pathway was activated in the tumor cells, and Pdgfr alpha, but not Kit, was overexpressed and activated. Lineage tracing revealed that Cre-expressing intestinal cells were Kit-negative. These cells sometimes expressed Pdgfr alpha and were located near Kit-positive interstitial cells of Cajal. In contrast to KIT, activation of PDGFRA increased anchorage-independent proliferation and was required for tumor formation in mice by cells with activated HH signaling. CONCLUSIONS: Inactivation of Ptch in mice leads to formation of GIST-like tumors that express Pdgfr alpha, but not Kit. Activation of Pdgfr alpha signaling appears to facilitate tumorigenesis."],["dc.identifier.doi","10.1053/j.gastro.2012.09.061"],["dc.identifier.isi","000312965100034"],["dc.identifier.pmid","23041331"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/31367"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","W B Saunders Co-elsevier Inc"],["dc.relation.issn","0016-5085"],["dc.title","Inactivation of Patched1 in Mice Leads to Development of Gastrointestinal Stromal-Like Tumors That Express Pdgfr alpha but Not Kit"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","2620"],["dc.bibliographiccitation.issue","10"],["dc.bibliographiccitation.journal","Journal of Investigative Dermatology"],["dc.bibliographiccitation.lastpage","2629"],["dc.bibliographiccitation.volume","134"],["dc.contributor.author","Uhmann, Anja"],["dc.contributor.author","Hess, Ina"],["dc.contributor.author","Frommhold, Anke"],["dc.contributor.author","Koenig, Simone"],["dc.contributor.author","Zabel, Sebastian"],["dc.contributor.author","Nitzki, Frauke"],["dc.contributor.author","Dittmann, Kai"],["dc.contributor.author","Luehder, Fred"],["dc.contributor.author","Christiansen, Hans"],["dc.contributor.author","Reifenberger, Julia"],["dc.contributor.author","Schulz-Schaeffer, Walter J."],["dc.contributor.author","Hahn, Heidi"],["dc.date.accessioned","2018-11-07T09:34:46Z"],["dc.date.available","2018-11-07T09:34:46Z"],["dc.date.issued","2014"],["dc.description.abstract","The development of basal cell carcinoma (BCC), the most frequently diagnosed tumor among persons with European ancestry, is closely linked to mutations in the Hedgehog (Hh) receptor and tumor suppressor Patched1 (Ptch). Using Ptch(flox/flox)CD4Cre(+/-) mice, in which Ptch was ablated in CD4Cre-expressing cells, we demonstrate that the targeted cells can give rise to BCC after treatment with DMBA (7,12-dimethylbenz(a)anthracene)/TPA (12-O-tetradecanoylphorbol-13-acetate), but not after wounding of the skin. In addition, in this model, BCC are not caused by malfunctioning of Ptch-deficient T cells, as BCC did not develop when bone marrow (BM) of Ptch(flox/flox)CD4Cre(+/-) mice was transplanted into Ptch wild-type mice. Instead, lineage-tracing experiments and flow cytometric analyses suggest that the tumors are initiated from rare Ptch-deficient stem cell-like cells of the epidermis that express CD4. As DMBA/TPA is a prerequisite for BCC development in this model, the initiated cells need a second stimulus for expansion and tumor formation. However, in contrast to papilloma, this stimulus seems to be unrelated to alterations in the Ras signaling cascade. Together, these data suggest that biallelic loss of Ptch in CD4(+) cells does not suffice for BCC formation and that BCC formation requires a second so far unknown event, at least in the Ptch(flox/flox)CD4Cre(+/-) BCC mouse model."],["dc.identifier.doi","10.1038/jid.2014.157"],["dc.identifier.isi","000342200400023"],["dc.identifier.pmid","24662765"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/32249"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Elsevier Science Inc"],["dc.relation.issn","1523-1747"],["dc.relation.issn","0022-202X"],["dc.title","DMBA/TPA Treatment Is Necessary for BCC Formation from Patched Deficient Epidermal Cells in Ptch(flox/flox)CD4Cre(+/-) Mice"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","e52898"],["dc.bibliographiccitation.issue","12"],["dc.bibliographiccitation.journal","PLoS ONE"],["dc.bibliographiccitation.volume","7"],["dc.contributor.author","Marklein, Diana"],["dc.contributor.author","Graab, Ulrike"],["dc.contributor.author","Naumann, Ivonne"],["dc.contributor.author","Yan, T."],["dc.contributor.author","Ridzewski, Rosalie"],["dc.contributor.author","Nitzki, Frauke"],["dc.contributor.author","Rosenberger, Albert"],["dc.contributor.author","Dittmann, Kai"],["dc.contributor.author","Wienands, Juergen"],["dc.contributor.author","Wojnowski, Leszek"],["dc.contributor.author","Fulda, Simone"],["dc.contributor.author","Hahn, Heidi"],["dc.date.accessioned","2018-11-07T09:02:08Z"],["dc.date.available","2018-11-07T09:02:08Z"],["dc.date.issued","2012"],["dc.description.abstract","We searched for a drug capable of sensitization of sarcoma cells to doxorubicin (DOX). We report that the dual PI3K/mTOR inhibitor PI103 enhances the efficacy of DOX in several sarcoma cell lines and interacts with DOX in the induction of apoptosis. PI103 decreased the expression of MDR1 and MRP1, which resulted in DOX accumulation. However, the enhancement of DOX-induced apoptosis was unrelated to DOX accumulation. Neither did it involve inhibition of mTOR. Instead, the combination treatment of DOX plus PI103 activated Bax, the mitochondrial apoptosis pathway, and caspase 3. Caspase 3 activation was also observed in xenografts of sarcoma cells in nude mice upon combination of DOX with the specific PI3K inhibitor GDC-0941. Although the increase in apoptosis did not further impact on tumor growth when compared to the efficient growth inhibition by GDC-0941 alone, these findings suggest that inhibition of PI3K may improve DOX-induced proapoptotic effects in sarcoma. Taken together with similar recent studies of neuroblastoma- and glioblastoma-derived cells, PI3K inhibition seems to be a more general option to sensitize tumor cells to anthracyclines."],["dc.description.sponsorship","DFG [GRK 1034, WO505/3-1]; Deutsche Krebshilfe [109837 (KoSAR)]"],["dc.identifier.doi","10.1371/journal.pone.0052898"],["dc.identifier.isi","000313872600033"],["dc.identifier.pmid","23300809"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/8548"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/24607"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Public Library Science"],["dc.relation.issn","1932-6203"],["dc.rights","CC BY 2.5"],["dc.rights.uri","https://creativecommons.org/licenses/by/2.5"],["dc.title","PI3K Inhibition Enhances Doxorubicin-Induced Apoptosis in Sarcoma Cells"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","831"],["dc.bibliographiccitation.issue","4"],["dc.bibliographiccitation.journal","Arthritis & Rheumatology"],["dc.bibliographiccitation.lastpage","840"],["dc.bibliographiccitation.volume","66"],["dc.contributor.author","Dittmann, Kai"],["dc.contributor.author","Wuelling, Manuela"],["dc.contributor.author","Uhmann, Anja"],["dc.contributor.author","Dullin, Christian"],["dc.contributor.author","Hahn, Heidi"],["dc.contributor.author","Schweyer, Stefan"],["dc.contributor.author","Vortkamp, Andrea"],["dc.contributor.author","Wienands, Juergen"],["dc.date.accessioned","2018-11-07T09:41:33Z"],["dc.date.available","2018-11-07T09:41:33Z"],["dc.date.issued","2014"],["dc.description.abstract","Objective. During development of the vertebrate skeleton, chondrocytes form a cartilage template that is gradually replaced by bone. Hormones of the Hedgehog (HH) family have been implicated in the ossification process, but their exact relationship to normal or pathogenic bone formation is unclear. This study was undertaken to establish a genetic tool that allows the discrete inactivation of genes in spinal chondrocytes, and to investigate in vivo how chondrocyte-specific ablation of the inhibitory HH receptor Patched 1 (Ptch1) affects skeleton integrity. Methods. A Cre-deleter mouse strain, mb1-Cre, for selective gene recombination in spinal chondrocytes was identified by in situ hybridization and histologic analysis. The mb1-Cre(+/-) animals were crossed with mice that harbor a loxP-flanked Ptch1 gene (Ptch1(flox/flox)) to abrogate the inhibition of the HH signaling pathway in chondrocytes. The skeletal integrity of F1 mice was characterized by high-resolution flat-panel-based volume computed tomography and histologic staining procedures. Results. During the first weeks after birth, all mb1-Cre(+/-)/Ptch1(flox/flox) mice developed progressive spinal fusion with malformation of the vertebrae. This phenotype was caused by aberrant chondrocyte proliferation in the intervertebral discs that blocked endochondral ossification. Importantly, the disease pattern occurred in an inflammation-independent manner. Conclusion. Our findings indicate that chronic activation of the HH signal pathway in spinal chondrocytes can trigger an ankylosing spine morphology without immune cell contributions. Hence, the destruction of cartilage and loss of axial joint integrity can result from chondrocyte-intrinsic defects of monogenic origin."],["dc.description.sponsorship","DFG [TRR130]"],["dc.identifier.doi","10.1002/art.38325"],["dc.identifier.isi","000337361000009"],["dc.identifier.pmid","24757136"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/33760"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Wiley-blackwell"],["dc.relation.issn","2326-5205"],["dc.relation.issn","2326-5191"],["dc.title","Inactivation of Patched1 in Murine Chondrocytes Causes Spinal Fusion Without Inflammation"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]