bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract B175: Lactadherin/MFGE8 favors bladder tumor progression by promoting tolerogenic immune responses
Authors: Bernard-Pierrot Isabelle , Sugano Gael , Laé Marick , Battail Christophe , Allory Yves , Stransky Nicolas , Krumeich Sophie , Donnadieu Marie-Helene , Abbou Claude , Benhamou Simone , Lebret Thierry , Sastre-Garau Xavier , Amigorena Sebastian , Radvanyi François , Thery Clotilde 
Published: June 2012

Abstract
MFG-E8/lactadherin is a secreted integrin-binding protein that promotes elimination of apoptotic cells by phagocytes leading to tolerogenic immune responses, and VEGF-induced angiogenesis, two important processes for cancer development. Here, by transcriptomic analysis of 229 biopsies of bladder carcinomas, we observed increasing expression of lactadherin with tumor progression, suggesting a protumoral role of lactadherin in this cancer. Consistently, using a mouse model of bladder carcinoma development due to carcinogen exposure, we showed that lactadherin-expressing mice developed more invasive tumors than lactadherin-deficient animals. We demonstrated that the proangiogenic function of lactadherin was not responsible for its protumoral role, since angiogenesis was similar in carcinogen-treated lactadherin-expressing or -deficient bladders, and since genes involved in VEGF-mediated angiogenesis were not co-regulated with lactadherin in human tumors. By contrast, we could ascribe the protumoral activity of lactadherin to its protolerogenic role, by showing that lactadherin expression did not promote tumor progression in mice devoid of adaptive immune system, and that lactadherin-overexpressing human tumors were invaded with immunosuppressive macrophages and regulatory T lymphocytes. Thus, lactadherin favors bladder tumor progression in human and mouse through its tolerogenic, rather than proangiogenic, function, and represents a promising therapeutic target in invasive bladder carcinomas.
Citation Information: Mol Cancer Ther 2009;8(12 Suppl):B175.
Abstract B177: Detection and quantification of ligand-receptor interactions in formalin-fixed paraffin embedded samples by a novel proximity-based assay
Authors: Dua Rajiv , Zhang Jianhuan , Parry Gordon , Penuel Elicia 
Published: June 2012

Abstract
Aberrant activation of membrane receptors frequently occurs in human carcinomas. Detection of phosphorylated receptors is commonly used as an indicator of receptor activation in formalin-fixed paraffin embedded (FFPE) sections, a format used to preserve human tissue samples. This is the only format for readily available tissues from clinical trials and patient disease management. However, phosphorylation is generally less stable and consequently, less reproducible which can, in a clinical setting lead to ambiguous data. Here, we describe an alternative, novel approach to detect and quantify activation of receptors in FFPE samples. We used the ligand/receptor, HGF/c-MET as our model system. HGF is the only known ligand of c-MET and ligand binding causes activation of the c-MET receptor. Using, the VeraTag technology, a proximity-based assay, validated antibodies were used to detect and quantify total c-MET and total HGF in FFPE samples as well as to detect and quantify ligand stimulated and endogenous HGF/c-MET interactions in FFPE cell line pellets. The detection was validated in human non-small cell lung and stomach carcinoma FFPE samples. Our data demonstrate a novel approach to detect and quantify ligand-receptor interactions by VeraTag proximity-based assays that can be widely applied to measure activation of receptors in archived FFPE human tissue samples.
Citation Information: Mol Cancer Ther 2009;8(12 Suppl):B177.
Abstract B186: Preclinical antileukemic activity of F14512, a novel targeted cytotoxic agent
Authors: Kruczynski Anna , Recher Christian , Pourtau Sandrine , Cartron Valérie , Marty Fabien , Vandenberghe Isabelle , Chansard Nathalie , Gallay Nathalie , Pillon Arnaud , Pesnel Sabrina , Le Pape Alain , Créancier Laurent , Menon Yoann , Gomes Bruno , Blanchet Jean-Christophe , Ricome Christel , Guminski Yves , Imbert Thierry , Payrastre Bernard , Bailly Christian , Demur Cécile , Guilbaud Nicolas 
Published: June 2012

Abstract
Despite advances in the therapy of acute myeloid leukemia (AML), the majority of patients die from their disease. Therefore, the lack of effective therapy mandates the development of novel compounds to improve the outcome of patients with relapsed and refractory leukemias. F14512 is a potent spermine-epipodophyllotoxin conjugate exploiting the polyamine transport system for tumor cell delivery. In this study, we report the in vivo antitumor activity of F14512 against experimental models of AML cell lines and of patient AML samples. F14512 markedly reduced the growth of HL-60 and U937 cell lines in an in vivo xenotransplantation model, resulting in a highly significant increase of survival of leukemia-bearing mice. Etoposide evaluated concurrently demonstrated only moderate in vivo activity against these models. F14512 induced in vivo apoptosis of HL-60 cells, as shown by caspase-3 activation and PARP cleavage. In an effort to mimic the human disease, we injected approximately 106 AML cells collected from a patient into NOD/SCID mice and allowed them to establish as xenografts for 8 weeks. Subsequent treatment with F14512 was carried out for 2 or 3 weeks followed by the analysis at the end of treatment and 1 week after the end of treatment. Two human AML samples were analyzed. Multiple i.v. administrations of F14512 at 0.32 mg/kg, induced an extensive reduction of the number of leukemic cells in mouse bone marrow and blood (97–99%), assessed by flow cytometry analysis, quantitative RT-PCR and histology. To identify leukemic cells expressing an active polyamine transport system, we developed a functional method based on the measurement of the cellular uptake of a nitrobenzoxadiazole fluorescent probe (F96982) combining the same spermine moiety as F14512. The level of fluorescence emitted by the probe F96982 was high in HL-60 cells as well in the 2 patient AML samples that proved to be sensitive to F14512 in vivo. Collectively, these results demonstrated that F14512 exhibits a marked in vivo antileukemic activity, supporting its clinical development. Phase I clinical trials in onco-hematology are now initiated with this novel promising drug candidate.
Citation Information: Mol Cancer Ther 2009;8(12 Suppl):B186.
Abstract B194: Enhanced antitumor activity of the HIF-1 inhibitor PX-478 combined with radiation and chemotherapy in pancreatic cancer
Authors: Powis Garth , Von Hoff Daniel , Bankson James , Iemos Robert , Hostetter Galen , Demeure Michael , Schwartz David 
Published: June 2012

Abstract
Growing tumors respond to hypoxic stress through increased expression of the HIF-1α transcription factor resulting in an adaptive switch to glycolytic metabolism, angiogenic signaling, survival, and metastasis. HIF-1α expression is associated with tumor resistance to cytotoxic therapy and inferior clinical outcomes. Pancreatic cancer is frequently associated with extensive desmoplasia, hypovascularity, and hypoxia, and is resistant to chemotherapy and radiation treatment. We have observed that HIF-1α is increased compared to normal pancreatic tissue in 24/32 (75%) of patent pancreatic ductal carcinoma samples, while 43% of the surrounding stromal tissue also showed elevated HIF-1α. Distal stroma showed no increase in HIF-1α. We have investigated the effects of the novel selective HIF-1α inhibitor PX-478 currently in Phase I clinical trial, on the in vitro and in vivo radiation response of human pancreatic cancer models. In pancreatic cancer cell lines, inhibition of HIF-1α by PX-478 was associated with increased cell killing by radiation with a radiation enhancement factor at 0.2 surviving fraction (SF2) in hypoxia (1% O2) of between 1.3 and 1.4. In mice with Panc-1 xenografts, 1 Gy QD alone × 5 yielded a tumor inhibition T/C at 70 days of 65% (with no regression), PX-478 20mg/kg po QD × 5 yielded a T/C of 14% (with 41% tumor regression) and the combination of 20mg/kg po PX-478 given daily 4 hr before 1 Gy × 5 provided a T/C of 8% (with 81% tumor regression). In CF-PAC-1, or SU.86.86 sc pancreatic xenografts, concurrent administration of 10 mg/kg PX-478 potentiated the antitumor effects of fractionated radiation and 5FU 20 mg/kg iv QD × 5 with a T/C of up to 3%, and with 66% tumor regression. In Panc-1 and SU.86.86 xenografts 20 mg/kg PX-478 potentiated the antitumor effects of radiation in combination with gemcitabine 120 mg/kg ip Q3D given one week later with a T/C of up to 8%, and with 80% tumor regression. Early tumor responses to combined PX-478/radiation treatment could be rapidly quantified by clinically relevant vascular imaging biomarkers. DCE-MRI and ultrasound imaging reproducibly discriminated tumor responses to PX-478 alone or combined with radiation as early as 10 days post-treatment, before differences in anatomic tumor size could be detected. Therefore, PX-478 is a mechanistically appealing and potentially clinically relevant enhancer of pancreatic cancer radiosensitivity, inhibiting tumor and stromal HIF-1 pro-angiogenic signaling and reducing the innate radiation resistance of hypoxic tumor cells. Supported by CA CA109552-05.
Citation Information: Mol Cancer Ther 2009;8(12 Suppl):B194.
Abstract B20: In vitro and in vivo antitumor activities of the dual PI3K/mTor inhibitor NVP-BEZ235. Implications for patient stratification strategies
Authors: Maira Michel , Brachmann Saskia , Fritsch Christine , Hofmann Irmgard , Schnell Christian , Garcia-Echeverria Carlos 
Published: June 2012

Abstract
The abnormal activation of the PI3K pathway is a recurrent feature observed in human tumors. Epidemiological and experimental studies have clearly underlined the role of this pathway for the maintenance of the tumorigenic state. A number of the intracellular components of this pathway have been targeted as anticancer drug discovery activities leading to clinical candidates like NVP-BEZ235. This compound, which is a dual pan-PI3K/mTOR, is currently undergoing Phase I clinical trials.To identify cancer patient populations that would benefit from NVP-BEZ235 treatment, the compound was profiled pre-clinically in a panoply of tumor cell lines, either in vitro or in vivo settings. Although not predictive from the in vitro antiproliferative data, the observed in vivo antitumor effects could be classified in three groups: strong, medium and low responders. Interestingly, 2 out of the 4 strong tumor xenograft responders presented genetic alterations of EGFR members. Constitutively active mutants or amplification of EGFR members is frequently observed in breast, ovarian and in non small cell lung cancer. Follow-up in vitro studies using a panel of over 40 breast cancer cell lines showed that a better understanding of tumor cell sensitivity to BEZ235 treatment could be obtained when cell death was used as a readout. ErbB2 amplification and/or PIK3CA activating mutations correlated well with cell death induction, but not PTEN deletion or mutations. An in depth analysis of death markers revealed that the cell death observed with BEZ235 could be recapitulated with other PI3K inhibitors and that this event is linked with active PARP cleavage reflective of an apoptotic process. Moreover, the effect seemed to be independent of Caspase-9 executioner and mitochondrial activated caspase, suggesting an alternate route for apoptosis induction by this class of compound. The exact mechanism is currently being elucidated. Overall, this study will provide guidance for patient stratification for forthcoming breast cancer Phase II trials for BEZ235
Citation Information: Mol Cancer Ther 2009;8(12 Suppl):B20.
Abstract B222: MUC16/CA125 synthetic lethal kinase screen for novel ovarian cancer targets
Authors: Eng Stephanie , Robin Manson , Zhou Qin C. , Thapi Dharmarao , Roslaes Nestor , Iasonos Alexia , Spriggs David R. 
Published: June 2012

Abstract
Background: MUC16 is a tethered, cell surface mucin which is over expressed on ovarian cancer cells and encodes the CA125 antigen. The CA125 antigen is present in the serum of women with ovarian cancer and appears to be an independent adverse marker of prognosis. Elements of the MUC16 molecule appear to promote invasion, alter gene expression and will induce malignant transformation in NIH 3T3 cells. We have previously demonstrated that MUC16 expression alters the expression of invasion/metastasis genes and genes linked to drug resistance. We hypothesize that the forced expression of MUC16 induces changes that might be relected in altered kinase activities and provides an opportunity to specifically target the MUC16+ ovarian cancer cell.
Methods: A human kinome siRNA library (2 siRNA's/well) was purchased from Qiagen. A2780 cells with and without MUC16 expression were labeled with GFP or mCherry Fluorescence proteins and plated in 96 well plates at 25000 cells/well. Each siRNA was plated into six replicate wells and analyzed for inhibition compared to negative controls and a proprietary “All Star Death” siRNA mix. If the candidate siRNA inhibited the proliferation of MUC16+ cells statistically (p&lt;0.05) more than MUC16 negative cells at 72hrs, that siRNA was scored as a “hit”.
Results: To date, we have screened siRNA's for a total of 160 of the planned 714 kinases. From the initial screen, we identified 28 kinase candidates for additional evaluation. Two additional siRNA's per kinase were obtained for confirmatory screening. From this initial group of kinases, inhibition of 3 kinases (CHEK1, ABL1 and CDK4) were significantly more inhibitory for MUC16+ cells than the syngeneic MUC16- comparator. Eight additional kinases (including CSK, CHUK, ILK and LTK) were more inhibited in the MUC16+ cells for 3 of 4 tested siRNA's for the target kinase. Although CDK4 protein levels were not altered in MUC16 transformed A2780 cells, CDK4 inhibitors were differentially active between the MUC16 +/- syngeneic pair and additional testing with other small molecule inhibitors is ongoing.
Conclusions: 1)MUC16 expression alters the biologic behavior of ovarian cancer cells and 2)MUC16 targeted, syngeneic screening of kinase siRNA libraries can identify potential clinical target candidates for ovarian cancer selected for MUC16.
Citation Information: Mol Cancer Ther 2009;8(12 Suppl):B222.
Abstract B226: Induction of growth arrest DNA damage-inducible gene 45 beta (GADD45b) expression contributes to sorafenib-induced apoptosis in hepatocellular carcinoma (HCC) cells
Authors: Ou Da-Liang , Shen Ying-Chun , Chen Kuen-Feng , Wang Ching-Tzu , Fan Hsiang-Hsuan , Yu Sung-Liang , Hsu Chiun , Cheng Ann-Lii 
Published: June 2012

Abstract
GADD45b, which is associated with cellular stress response and apoptosis regulation, was frequently under-expressed in HCC. In a previous study we found GADD45b belongs to a group of sorafenib-regulated genes that are independent of mitogen-activated protein kinase-extracellular signal-regulated kinase (MEK)/ extracellular signal-regulated kinase (ERK) signaling pathway. The present study explored the role of sorafenib-induced GADD45b expression in HCC cells. HCC cell lines tested included HepG2, Hep3B, Huh-7, and Huh-7R, a sorafenib-resistant cell line established by continuously exposure of Huh-7 cells to sorafenib. GADD45b expression was examined by quantitative real-time PCR and western blotting. Control of GADD45b transcription was examined by luciferase reporter assay using a series of reporter plasmids with deletions or site-directed mutants of the 5′-flanking region of GADD45b promoter. Apoptosis was analyzed by measuring the subG1 fraction and annexin V staining using flow cytometry. Both the mRNA and the protein levels of GADD45b was increased after sorafenib but not after the MEK inhibitor CI-1040 or U0126 treatment, suggesting that GADD45b induction was independent of cellular MEK/ERK activity. GADD45b induction was more prominent in sorafenib-sensitive HCC cells (Huh-7 and HepG2, IC50 6–7 µM) but less so prominent in sorafenib-resistant HCC cells (Hep3B and Huh-7R, IC50 12–15 µM). Knockdown of GADD45b expression by siRNA partially abrogated the pro-apoptotic effects of sorafenib in Huh-7 and HepG2 cells but not Hep3B cells. The region −339/−267 in the 5′-flanking region of GADD45b promoter, which contained AP-1 (−298/−292) and Sp1 (−285/−277) binding sites, was found crucial for GADD45b induction by sorafenib. Binding of c-Jun and Sp1 to GADD45b promoter was confirmed by chromatin immunoprecipitation. Sorafenib also increased the phosphorylation of JNK in sorafenib-sensitive but not in sorafenib-resistant HCC cells. Sorafenib-induced GADD45b expression can be alleviated by treatment with the specific JNK inhibitor SP600125. Our data indicated that induction of GADD45b expression, which is mediated by cellular JNK/c-Jun signaling pathway but not MEK/ERK signaling, contributes to sorafenib-induced apoptosis in HCC cells. Failure of GADD45b induction may confer sorafenib resistance. GADD45b may be used as a predictive biomarker for sorafenib sensitivity in HCC. (Supported by grants NSC97-3112-B-002-012, NSC98-3112-B-002-007, NSC98-3112-B-002-037)
Citation Information: Mol Cancer Ther 2009;8(12 Suppl):B226.
Abstract B228: A hepatocyte growth factor antagonist engineered by targeted disruption of heparan sulfate binding
Authors: Cecchi Fabiola , Pajalunga Deborah , Rabe Daniel , Fowler Andrew C. , MacDonald Nicholas , Blackman Davida K. , Stahl Stephen J. , Byrd Andrew R. , Bottaro Donald P. 
Published: June 2012

Abstract
Hepatocyte growth factor (HGF) stimulates cell proliferation, motility, and morphogenesis upon binding to the receptor tyrosine kinase Met and cell surface heparan sulfate (HS) glycans. NK1 is a truncated HGF isoform consisting of the N-terminal (N) and first kringle (K1) domains of full-length HGF that stimulates all major HGF biological activities. Within NK1, the N domain contains the HS binding site, while K1 contains the primary determinants of Met binding. To further define the role of HS in ligand-receptor interaction and biological signaling, we identified the primary HS binding residues in N domain (K60, K62, R73) and generated opposite charge mutations at these positions in NK1. Nuclear magnetic resonance analysis of recombinantly expressed mutant and wild type (WT) proteins revealed that both were folded normally. Mutant proteins displayed diminished binding to immobilized HS relative to WT, and the triple mutant protein (3M) also lacked intrinsic motogenic and mitogenic activity. Interestingly, 3M NK1 maintained Met binding and competitively inhibited DNA synthesis stimulated by WT NK1 as well as full-length HGF in normal cells. Expression plasmids encoding 3M and WT NK1 proteins were transfected into the glioblastoma cell U87 MG, which is dependent on HGF/Met autocrine signaling for tumorigenicity in mice. 3M/U87 MG cells displayed a substantially lower rate of growth relative to WT/U87 MG or the parental cell line, suggestive of growth antagonism by 3M NK1. As anticipated, expression of WT NK1 significantly accelerated the growth of U87 MG tumor xenografts in mice, which reached maximal volume (1 ml) by 22 days post-implantation, compared to 45 days required by the parental cell line. In contrast, tumor growth in animals injected with 3M/U87 MG was dramatically impaired: at 60 days post implantation, average tumor volume for this group was &lt; 0.3 ml. Because both WT and 3M transfectants expressed equal amounts of their respective recombinant proteins, the HS binding site mutations delayed measurable tumor growth from one week to two months. Thus HS binding is critical for HGF-driven mitogenesis and tumor growth, and inhibition of these activities by 3M NK1 validates a novel strategy for developing antagonists of the HGF pathway and potentially those of other HS-binding ligands
Citation Information: Mol Cancer Ther 2009;8(12 Suppl):B228.
Abstract B234: Dual targeting of the tyrosine kinase receptors EGFRvIII and c-Met in glioblastoma multiforme
Authors: Pillay Vinochani , Scott Andrew M. , Johns Terrance G. 
Published: June 2012

Abstract
The most common mutation of the epidermal growth factor receptor (EGFR) in glioblastoma multiforme (GBM) is an extracellular truncation of 267 amino acids known as EGFRvIII (or de2-7 EGFR). While the EGFRvIII is unable to bind any known ligand, it displays a low level of constitutive activation that is enhanced by its inability to undergo downregulation. HGF/SF is the ligand for the receptor tyrosine kinase c-Met, both of which are often co-expressed in GBM. The presence of the HGF/c-Met axis or expression of EGFRvIII each independently enhances GBM growth, angiogenesis capacity, migration and invasiveness. Using tyrosine kinase array technology, we now show that expression of EGFRvIII in U87MG glioblastoma cells (U87MG. 2-7 cells) leads to co-activation of several receptor tyrosine kinases, including PDGFR and c-Met. A fully human neutralizing antibody directed to HGF (AMG 102) did not inhibit this EGFRvIII mediated activation of c-Met in vitro, demonstrating that it is ligand independent. We examined if this transactivation of c-Met influenced the efficacy of therapies targeting the HGF:c-Met axis. Treatment of parental U87MG xenografts with low doses of AMG 102 resulted in significant inhibition of tumor growth (see Burgess et al. 2006), while U87MG. 2-7 xenografts (see Johns et al 2007) were profoundly resistant to AMG 102 treatment. Treatment with Panitumumab, a fully human antibody directed to the EGFR and EGFRvIII, was able to inhibit the EGFRvIII mediated activation of c-Met and significantly reversed the resistance to AMG 102 observed in U87MG. 2-7 xenografts. Indeed, combination therapy with Panitumumab and AMG 102 resulted in a marked increase in tumor cell apoptosis, especially in the central parts of the xenograft. An EGFRvIII molecule with an active kinase but incapable of autophosphorylation at the five major autophosphorylation sites (tyrosine changed to phenylalanine) involved in signal transduction was also able to mediate resistance to AMG 102, suggesting that the activation of c-Met by EGFRvIII occurs via a direct interaction rather than through these docking sites. These studies show that expression of EGFRvIII leads to the promiscuous activation of several kinases, causing resistance to ligand inhibitory based strategies. Since Panitumumab can reverse this process, the combination of this antibody with AMG 102 may be an effective treatment for GBM patients positive for EGFRvIII.
Citation Information: Mol Cancer Ther 2009;8(12 Suppl):B234.