bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 4291: Functional p38 mitoge-activated protein kinase activity restrains pancreatic cancer growth in vitro and correlates with improved eurvival of pancreatic cancer patients
Authors: Zhong Yi , Naito Yoshiki , Iacobuzio-Donahue Christine A.
Published: July 2012

Introduction: Mammalian p38 mitogen-activated protein kinases (MAPKs) are activated by a wide range of cellular stresses as well as in response to inflammatory cytokines. However, depending on the cell type, p38 MAPK family members and their isoforms may either suppress or promote growth. Because we recently identified p38 as a differentially expressed protein in pancreatic duct adenocarcinoma (PDAC), our goal was to clarify its role in this tumor type.

Methods: Immunolabeling for phospho-p38 was performed using a rabbit PAb (Cell Signaling). Kaplan Meier survival plots were determined based on p38 labeling intensity. Total protein was extracted from PDAC cell lines and used for Western blot analysis of p38 expression. Functional kinase activity was also determined by the p38 kinase assay. Growth of PDAC cell lines in vitro was determined in the presence or absence of the p38 inhibitors SB202190, SB203580 and SB239063 by MTT assay.

Results: Immunolabeling for phospho-p38 in PDAC tissues indicated strong positive expression in 65.06% (54/83) of analyzed cases. p38 overexpression was significantly correlated with prolonged overall survival of these same patients by Kaplan Meier analysis (p=0.0155). By Western blot, phospho-p38 expression was confirmed in a subset of PDAC cell lines, and correlated with functional p38 kinase activity in these same cell lines. Inhibition of p38 MAPK activity using the selective p38 inhibitors SB202190 and SB203580 inhibited starvation and gemcitabine-induced cell death in PDAC cells with high p38 activity compared with vehicle control. By contrast, there was no significant difference in cell growth in PDAC cells without p38 activity when treated with these same p38 inhibitors compared with untreated control cells.

Conclusions: Functional p38 MAPK expression restrains cell growth in vitro, and phospho-p38 overexpression in vivo correlates with improved survival of PDAC patients. These studies support the notion that p38 has anti-proliferative or tumor suppressive functions, and that loss of p38 expression prevents cell stress induced sensitization to cell death.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4291. doi:10.1158/1538-7445.AM2011-4291
Abstract 4293: Notch expression expands the pre-malignant pool of T-cell acute lymphoblastic leukemia clones without affecting self-renewal
Authors: Blackburn Jessica S. , Liu Sali , Langenau David M.
Published: July 2012

Over 60% of human T-cell acute lymphoblastic leukemias (T-ALL) harbor NOTCH1 activating mutations, and the cMYC pathway is also commonly activated in this disease. Notch and cMyc have been shown to collaborate in mouse transgenic models of T-ALL, suggesting that these oncogenes function in parallel pathways to enhance tumor growth; however, the exact role of each in T-ALL is unknown. Here, we show that co-expression of Notch and cMyc in zebrafish T cells significantly enhances T-ALL progression compared to cMyc or Notch alone (p<0.001). However, Notch co-expression with cMyc does not enhance proliferation, alter cell cycle kinetics, or modify apoptosis in leukemic cells when compared to T-ALLs expressing cMyc alone. Clonality assays using RT-PCR analyses for T-cell receptor-beta rearrangements indicate that Notch increases the number of T-ALL clones contained within the primary tumor when compared to cMyc expressing leukemais. A large portion of T-ALL clones present in primary Notch and Notch/cMyc leukemias cannot transfer disease into transplanted animals, while all cMyc-alone expressing T-ALLs clones are capable of engraftment and reinitiation of leukemia. Large scale limiting dilution cell transplantation analyses using syngeneic zebrafish demonstrated that primary T-ALLs expressing either Notch or Notch/cMyc have 10-fold less leukemia-initiating frequency when compared to T-ALLs that express only cMyc; however, following serial passaging, both the Notch and Notch/cMyc leukemias exhibit similar leukemia-initiating frequency as cMyc-induced T-ALLs, indicating that Notch signaling does not enhance self-renewal of T-ALL initiating cells. Taken together, our data supports a model where Notch expands a pool of pre-malignant T-ALL clones within the primary tumor, a subset of which acquire additional mutations to confer a fully transformed phenotype. By contrast, cMyc alone is insufficient to increase the overall pool of pre-malignant clones but confers a fully-transformed phenotype to leukemic cells, accounting for the longer latency that likely reflects the acquisition of additional genetic changes in clones. Our data may explain why a subset of relapsed human T-ALLs develop from an underrepresented clone found in the primary leukemia, in that primary human T-ALLs likely have a large pool of pre-malignant clones resulting from NOTCH-pathway activation that are unable to self-renew and thus, cannot give rise to relapsed T-ALL.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4293. doi:10.1158/1538-7445.AM2011-4293
Abstract 4294: Using the zebrafish model to determine the role of the HACE1 tumor suppressor in apoptosis, cell proliferation and development
Authors: McDonald Lindsay A. , Da'as Sahar , D'Alessandro Paul , Sorensen Poul H. , Berman Jason N.
Published: July 2012

HACE1 is a novel tumor suppressor gene located at human chromosome 6q21. HACE1 possesses both ankyrin repeats and a catalytically active HECT domain. HACE1 is downregulated in a variety of human cancers including Wilms’ tumor, melanoma, breast cancer, lung cancer, lymphoma, and colon cancer, thus representing a potentially broadly applicable genetic target. While HACE1 is widely expressed in human tissues, its role in normal development remains unknown. The zebrafish has established itself as a robust model for studying vertebrate development and modeling human cancers by virtue of conserved genetics and direct evaluation of gene expression through imaging afforded by transparent embryos. A zebrafish hace1 homologue has been identified. Whole mount in situ hybridization (WISH) assays with probes to the ankyrin repeats and HECT domains demonstrate expression of zebrafish hace1 in heart, brain and kidney at early developmental time points (24 hours post-fertilization (hpf) – 7 days post-fertilization (dpf)), consistent with human expression. WISH studies in wild type embryos, employing probes to the zebrafish hace1 HECT domain and cmcl2 (heart) or cdh17 (kidney), show co-localization at early developmental time points. Moreover, morpholino knockdown of hace1 in cmcl2-GFP transgenic embryos reveals severely perturbed cardiac development and function beginning at 48 hpf, further implicating this gene in normal vertebrate cardiac development. We have also generated two transgenic zebrafish lines harboring either wild type or dominant negative mutated C876S (C876S DN) human HACE1 genes with a green fluorescent protein (GFP) tag under the control of the ubiquitous β-actin promoter. Compared to wild type embryos, we observed increased apoptosis in 28 hpf C876S DN by acridine orange and caspase 3 assays, both untreated and following irradiation-induced cellular damage. There was no statistically significant difference in cellular proliferation between wild type embryos and C876S DN by 5-bromo-2-deoxyuridine (BrdU) incorporation (p=0.18). These results suggest that loss of HACE1 function alone is not sufficient to lead to a dysregulated cellular proliferation and implicate additional genetic lesions, such as p53 in tumor formation. C876S DN transgenic zebrafish are being crossed with p53 mutated zebrafish in order to determine the combined effect of both mutations on apoptosis, cell proliferation, and tumor formation. Further characterization of the HACE1 transgenic zebrafish model will serve to better our understanding of the role of human HACE1 in normal development and tumorigenesis.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4294. doi:10.1158/1538-7445.AM2011-4294
Abstract 4295: High-throughput screening of osteosarcoma progression: A zebrafish model
Authors: Mohseny Alexander B. , Xiao Wei , Carvalho Ralph , Spaink Herman P. , Hogendoorn Pancras CW , Cleton-Jansen Anne-Marie
Published: July 2012

Background: Osteosarcoma is the most common primary malignant bone tumour of non-hematologic origin. The survival of the patients has reached a plateau phase partly due to a poor understanding of osteosarcoma tumorigenesis. Previously we identified murine mesenchymal stem cells (mMSCs) that formed aggressive osteosarcoma-like lesions after injection in mice (Mohseny et al. J Pathol. 2009 Nov;219(3):294-305). In the current study we aimed to set up a high-throughput model to confirm the mMSCs transformation and to investigate further progression of these cells in vivo.

Methods: The mMSCs were isolated from the bone marrow of C57BL/6 as well as BALB/c mice and cultured for 8 months. Cells of early and late passages were labeled with a fluorescent dye (CM- Dil) and injected into the yolk sacs of 2-days old transgenic zebrafish embryos with GFP labeled vascular system. The embryos were subjected to live imaging for 3 days to screen for cell homing, proliferation, migration and angiogenesis. Subsequently genome wide mRNA expression analysis for both zebrafish and mouse transcripts was performed.

Results: The mMSCs were confirmed to transform in vitro after a period of crisis. High passage mMSCs, i.e. after the transformation, could proliferate, migrate into the fish body and induce angiogenesis whereas low passage MSCs, i.e. prior to transformation, did not. The microarray expression study was technically feasible as mouse transcripts from injected cells were detectable among the more abundant zebrafish RNA.

Conclusions: The present study corroborates mMSCs transformation during long-term in vitro culturing. Furthermore it provides an efficient zebrafish model for studying mMSCs tumourigenic progression to characterize clinical relevant processes like migration and angiogenesis. After analyzing both mMSCs and zebrafish embryos on gene-expression level, the differential behavior of normal and transformed mMSCs as well as the host response can provide new insights into osteosarcoma progression.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4295. doi:10.1158/1538-7445.AM2011-4295
Abstract 4299: CD150, A predictor for xenotransplantation of acute lymphoblastic leukemia to NOD/SCID mice
Authors: Huang Liang , Wang Na , Ma Shuyan , Liu Jingping , Wang Min , Song Xiaoming , Chen Shi , Chen Taiping , Chen Yiyou , Zhou Jianfeng
Published: July 2012

CD150 is a member of the SLAM family that recently has been reported to be differentially expressed among primitive progenitors in the bone marrow of adult mouse. It was utilized to purify hematopoietic stem cells using a simple combination of SLAM family members. To elucidate the presence of this family on acute lymphoblastic leukemia (ALL), we analyzed the expression of this family member on human B-ALL progenitor cells, as well as its relationship with the engraftment of leukemic blasts in serial xenotransplantation assay. Expression analysis was carried out by flow cytometry. We combined the expression pattern of human CD150, CD244 and CD48 with serial xenotransplantation of B-ALL progenitor cells to indicate their relationship. Our data showed that CD48 and CD244 were expressed on most B-ALL progenitor cells, and interestingly only blast cells with low percentage of CD150+ population were able to reconstitute leukemia into primary, secondary and tertiary NOD/SCID mice. In conclusion, SLAM family members are present on B-ALL progenitor cells and the engraftment potential of leukemic blasts is correlated negatively with the proportion of CD150+ cells, the percentage of which can serve as a useful predictor for graft success of B-ALL to immune deficient mice. The mechanism of CD150 as a predictor is under further investigation.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4299. doi:10.1158/1538-7445.AM2011-4299
Abstract 430: 4F2hc mediates renal cancer cell (RCC) behavior
Authors: Poettler Marina , Kalinowska Waclawa , Novotny Rene , Braemswig Kira H. , Haitel Andrea , Susani Martin , Zielinski Christoph C. , Prager Gerald W.
Published: July 2012

4F2, a transmembrane protein, has a heteromeric structure, consisting of a heavy subunit (4F2hc, CD98hc, SLC3A2) and a light subunit, extracellular linked together via disulfid bounds. The light chains provide amino acid transport activity, while the heavy chain physically interacts with a conserved motif of integrin beta subunits, thereby mediating adhesion-induced signal transduction. A genetic knockout of 4F2hc in animals is embryonic lethal, overexpression of 4F2hc in somatic cells leads to malignant transformation.

In the present study we aimed to characterize 4F2hc expression in renal cell cancer (RCC) as a diagnostic or prognostic marker, as well as to indentify a potential functional role of 4F2 in tumor cell behavior. By immunohistochemistry and analysis of multi tissue arrays, we found that 4F2hc is highly expressed in papillary, clear cell and chromophobe RCC, while no 4F2hc expression was found in benign tumors, such as oncocytomas. Thereby, 4F2hc expression directly correlated with grade of differentiation suggesting 4F2hc as a novel and reliable marker for the more malignant subtype II papillary renal cell cancer (type II 83.34 %, type I 4.76 % 4F2hc positive, p < 0.00001; n = 51).

To evaluate a potential functional role of 4F2 in renal cancer cell behavior, we generated a stable low 4F2hc clear cell RCC cell line (93% downregulation) and compared the protein expression as well as the tumor cell behavior with a high expressing mock transfected counterpart cell line. We found that tumor cell behavior such as cell proliferation, cell survival and cell migration were significantly impaired, whenever 4F2 expression was downregulated. As 4F2 light chain distribution to cell surface is dependent on 4F2hc, leucine amino acid transport in low 4F2hc/Caki2 cells is impaired, as shown by C14-leucine uptake assays. Transfection of silent mutations either lacking integrin interaction site (delta WALLL) or amino acid transport capabilities (Cys109_330Ser) in low4F2/ Caki2 cells revealed a functional relevance of 4F2hc upon tumor cell behavior.

From these data we conclude that 4F2 (1) represents a promising new diagnostic marker for RCCs, whereby grade of differentiation correlates with amount of 4F2 expression, and (2) 4F2 might play a functional role in renal cancer cell behavior.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 430. doi:10.1158/1538-7445.AM2011-430
Abstract 4300: Selective GFP labeling of cancer with a telomerase-specific adenovirus (OBP-401) to report future recurrence after resection
Authors: Kishimoto Hiroyuki , Aki Ryoichi , Urata Yasuo , Bouvet Michael , Momiyama Masashi , Tanaka Noriaki , Fujiwara Toshiyoshi , Hoffman Robert M.
Published: July 2012

We have previously developed a telomerase-specific replicating adenovirus expressing GFP (OBP-401). Intraperitoneal (i.p.) injection of OBP-401 specifically labeled peritoneal tumors with GFP enabling real-time surgical navigation. However, technical difficulty of removing microscopic tumors still remains, which makes it difficult to eradicate disease completely, even after so-called complete resection. In this study we report an additional advantage of OBP-401. Weeks after surgical navigation with OBP-401, recurrent tumor nodules were observed with GFP imaging, indicating that OBP-401 treatment for peritoneal disseminated disease enabled detection of its subsequent recurrence after surgical navigation. Thus tumor labeling with a genetic reporter has important advantages over antibody and other non-genetic labeling since reminant disease remains labeled and can be further resected.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4300. doi:10.1158/1538-7445.AM2011-4300
Abstract 4301: Deletion-mapping identifies the regions within MN1 that regulates its transforming activity in hematopoietic cells
Authors: Kandilci Ayten , Bonten Jacqueline , Janke Laura , Neal Geoffrey , Terranova Sabrina , Grosveld Gerard
Published: July 2012

The oncogene MN1 is deregulated in human acute myeloid leukemias and its overexpression is known to induce proliferation and repress myeloid differentiation of primitive human and murine hematopoietic cells, which causes myeloid leukemia in mouse models. To study the role of different regions within MN1 in MN1-induced leukemia, we generated in-frame deletion mutants of the protein. Using retroviral transduction assays, we found that the regions between amino acids 12 to 228 and 570 to 1273 are required for its in vivo transforming activity, although the 12-228-mutant was still capable of repressing myeloid differentiation and inducing self-renewal in vitro. Both MN1 and the 12-228-mutant increased the frequency of common myeloid progentiors (CMP) in vitro and microarray comparison of purified CMPs identified Hoxa9, Meis1, Myb, Cebpa, Cebpb and Cebpd among many other differentially expressed transcripts as potential candidates that mediate MN1-induced leukemia.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4301. doi:10.1158/1538-7445.AM2011-4301
Abstract 4302: Targeting the sphingolipid pathway in NK large granular lymphocyte leukemia
Authors: Watters Rebecca J. , Liu Xin , Fox Todd E. , Kester Mark , Loughran Thomas P.
Published: July 2012

Large granular lymphocytes (LGL) are a lymphoid subset that consists of 10-15% of peripheral blood mononuclear cells. LGL can be divided into (2) major lineages of CD3- NK cells and CD3+ T Cells. Symptoms may include rheumatoid arthritis and neutropenia which leads to recurrent bacterial infections. The sphingolipid metabolism pathway has been found to be deregulated in NK-LGL leukemia. Glucosylceramide synthase (GCS), a key component of this pathway is an enzyme that catalyzes the conversion of proapoptotic ceramide to inactive glucosylceramide by transferring a glucose residue from UDP-glucose to ceramide. GCS has been found to be upregulated in cancer cells and its overexpression has been associated with multidrug resistance in leukemia cells. Both rat and human leukemic LGL cells have been treated with a combination treatment targeting two key components of the sphingolipid pathway. One of the agents in use is the C6-ceramide (C6) nanoliposome which has led to caspase-dependent apoptosis in a time- and dose-dependent manner. Systemic i.v. delivery of nanoliposomal ceramide led to complete remission in 5/14 syngeneic Fischer F344 rat model of NK-LGL leukemia. However a greater response will be achieved by combination treatment of C6 and through targeting a second key component of ceramide metabolism with DL-threo-1-Phenyl-2-palmitoylamino-3-morpholino-1-propanol (PPMP). PPMP is a GCS inhibitor that prevents the endogenous ceramide already present in the cell from being glycosylated into its inactive form where it can no longer induce cell death. Overall, this combination treatment shows a synergistic effect with increase of ceramide levels in order to induce apoptosis and therefore death of these persistent LGL cells. Cell flow cytometry examining 7AAD/Annexin V staining has shown ∼80% apoptosis when 6.25 uM C6 ceramide and 15 uM PPMP are used in combination on aggressive rat LGL cells. Whereas, only ∼19% is observed with C6 and ∼17% of PPMP are observed individually in treatment. Overall, apoptosis appeared increased in a dose response manner after treatment with PPMP and C6. This is a significant finding of P<0.005, when compared to DMSO and ghost nanoliposome controls which only induce ∼15% apoptosis. In addition, this combination treatment has been utilized on normal human peripheral blood mononuclear cells where only 11.2% apoptosis was induced and 9% in the normal spleen mononuclear cells in rats. As a result, this combination treatment appears promising in specifically targeting LGL cells while sparing normal cells.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4302. doi:10.1158/1538-7445.AM2011-4302
Abstract 4303: The Jackson Laboratory Repository: resource for mouse strains modeling cancer
Authors: Boswell Deborah M. , Donahue Leah Rae , Lutz Cathleen M. , Rockwood Stephen F. , Sasner Michael
Published: July 2012

The Jackson Laboratory Repository is an established resource for the importation, cryopreservation, development, and distribution of mouse strains vital to biomedical research. More than 500 new strains are added annually to the approximately 5,000 strains and stocks of mice currently held in the Repository collection.

Newly acquired or developed strains include a model of malignant melanoma and metastasis; a xenotransplant model that provides continuous circulation of human growth factors; a targeted mutation strain for studying myeloproliferative diseases such as chronic myelomonocytic leukemia and Chronic Familial Myelocytic Leukemia-Like Syndrome; and a knock-in strain that mimics the t(9;11)(p22;q23) translocation identified in acute myeloid leukemia. Also under development are a transgenic/targeted mutation strain with increased mammary gland tumor incidence and three targeted mutation strains with increased sensitivity to carcinogens or radiation.

The Repository's inducible and conditional mutation mouse strains allow researchers to generate temporal and/or tissue-specific tools for modeling human cancer. New additions to the Repository collection include strains with Cre recombinase expression specific to the colon and rectum, as well as a transgenic strain that can be used as part of a bitransgenic system utilizing the tetracycline-inducible expression of a gene of interest in blood vessel endothelial cells. For non-invasive in-vivo imaging studies, the Repository distributes a xenograft/transplant host with widespread expression of firefly luciferase and enhanced green fluorescence protein.

The Repository maintains a searchable on-line resource (www.jax.org) for each strain. Researchers can submit their strains to be considered for inclusion in the Repository by using the on-line form available at The Jackson Laboratory website: http://www.jax.org/grc/index.html.

The Jackson Laboratory Repository is supported by the NCRR, The Howard Hughes Medical Institute, The Ellison Medical Foundation and donations from private charitable foundations.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4303. doi:10.1158/1538-7445.AM2011-4303
Abstract 4304: Developing T-LGL leukemia model for targeted therapy
Authors: Ren Tong , Liu Xin , Loughran Thomas P. , Cheng Hua
Published: July 2012

T cell type of large granular lymphocyte (T-LGL) leukemia is a hematological malignancy and the disease course is frequently associated with autoimmune diseases. Many patients with T-LGL leukemia have no response to the currently available immunosuppressive therapies. T-LGL leukemia cells display the CD3+/CD8+/CD57+ surface markers, representing activated cytotoxic T lymphocytes with the TCR rearrangement pattern that implicates their clonal expansion nature. The primary leukemic cells exhibit constitutive activities of STAT3 and NF-κB, and both factors are critical mediators of oncogenic signaling and survival pathways. Activated STAT3 contributes to chemotherapy resistance as the repression of STAT3 in LGL leukemic cells down-regulates a survival protein Mcl-1, resulting in an increased sensitivity to apoptosis. Thus, STAT3 activation plays an essential role in promoting aberrant proliferation of the leukemic cells. In addition, NF-κB is activated in LGL leukemia, which also plays a crucial role in survival and proliferation of the leukemia cells. It is of paramount significance to further verify therapeutic agents that target STAT3 and NF-κB for treatment of T-LGL leukemia in a well-defined leukemia model. Extensive efforts, however, failed to establish in vitro culture of primary T-LGL leukemia cells for extended time, because T-LGL leukemia cells are terminally differentiated cytotoxic T lymphocytes and undergo rapid replicative senescence. Lack of T-LGL leukemia model apparently prevents further understanding of the disease pathogenesis and development of targeted therapy.

We have developed a strategy that can prolong in vitro culture of T-LGL leukemia cells. Primary CD8+ populations from T-LGL leukemia patients are stably transduced with the retroviral tax gene derived from human T cell leukemia virus type 2. Expression of Tax overrides replication senescence and promotes unlimited expansion of the CD8+ T cells. These cells exhibit features characteristic to T-LGL leukemia, such as resistance to FasL-mediated apoptosis, sensitivity to inhibitors for sphingolipid kinase, IκB kinases and Stat3 as well as expression of cytotoxic gene products including granzyme B, perforin and IFNγ. Collectively, these results indicate that the immortalized CD8+ species from T-LGL leukemia patients constitutes a significant portion of T-LGL leukemic cells, and this leukemia model can duplicate main phenotypes of clinical isolates of T-LGL leukemia. The establishment of the T-LGL leukemia model is tremendously useful for investigating molecular pathogenesis of the disease and for testing novel therapeutics.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4304. doi:10.1158/1538-7445.AM2011-4304
Abstract 4305: Invasion of primary glioma- and cell line-derived spheroids implanted into corticostriatal slice cultures
Authors: Aaberg-Jessen Charlotte , Norregaard Annette , Christensen Karina Garnier , Jensen Stine Skov , Andersen Claus , Kristensen Bjarne Winther
Published: July 2012

Gliomas are known for being highly invasive and therefore incurable by surgery explaining a recurrence rate close to 100%. The aim of the present study was to develop and evaluate an in vivo-like in vitro model preserving the invasive features of glioma cells in order to facilitate research using more true models. This study was performed by implantation of glioma spheroids into organotypic corticostriatal slice cultures. The spheroids chosen for implantation were primary glioma spheroids as well as spheroids derived from the U87 glioblastoma cell line. Primary glioma spheroids are cultured small glioma fragments obtained from freshly removed tumor tissue. In contrast to cell line-derived spheroids, primary glioma spheroids preserve the tumor tissue components and structures such as cell-to-cell interactions, blood vessels and macrophages. In the present study, primary glioma spheroids from one anaplastic astrocytoma (WHO grade III) and two glioblastomas (WHO grade IV) were included in addition to U87 spheroids. The spheroids were labelled with the fluorescent dye DiI and implanted into 400 µm thick corticostriatal slice cultures prepared from newborn rat pups. The tumor cell invasion was followed by confocal microscopy. Hereafter the co-cultures were prepared for anti-human vimentin immunohistochemical staining identifying invasive tumor cells. The results showed that the primary glioma spheroid area was constant after implantation, but there was a clear increase in number of invading cells with time. In contrast, the U87 spheroid area increased after implantation, but there was only relatively few invading cells entering the brain tissue. Anti-human vimentin stained paraffin sections of co-cultures confirmed the tumor cell invasion recorded by confocal microscopy. The present study suggests implantation of primary glioma spheroids into corticostriatal slice cultures as an excellent in-vivo like in-vitro model suitable for studies of invasion. Similar to earlier results obtained in vivo, the U87 cell line, when used in vitro as well, appears to have lost the invasive feature of gliomas, preventing the use of this cell line in studies of invasion.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4305. doi:10.1158/1538-7445.AM2011-4305
Abstract 4306: KLF8 promotes human ovarian tumorigenesis in athymic mouse models
Authors: Lu Heng , Wang Xianhui , Urvalek Alison M. , Li Tianshu , Yu Lin , Zhao Jihe
Published: July 2012

KLF8 is a dual transcription factor that plays a role in oncogenic transformation in mouse fibroblast cells and is highly over-expressed in human ovarian cancer. To test if KLF8 alone or together with each of the ovarian oncoprotein c-Myc, Stat3c or Akt plays a role in ovarian cell transformation, we used the immortalized normal human ovarian epithelial cell line T80 to generate stable cell lines that overexpress KLF8 alone or its combination with one of the other three oncoproteins. The Soft agar assay showed that T80/KLF8 formed significantly more colonies compared with the mock control cells, suggesting that KLF8 may play a role to transform T80 cells. Interestingly the cells expressing both KLF8 and c-Myc formed the largest amounts of colonies that were even greater than the sum of colonies formed by the cells expressing either KLF8 or c-Myc alone, suggesting a potential synergistic role of KLF8 with c-Myc. Surprisingly, however, overexpression of KLF8 alone was sufficient to induce tumorigenesis in athymic mice when the T80/KLF8 cells were injected subcutaneously (s.c.), intraperitoneally (i.p.) or orthotopically into the ovarian bursa. HE and IHC staining identified the tumors’ epithelial origin characteristic of human ovarian cancer. The s.c. growth rate of the T80/KLF8 tumors was greater than the T80/Stat3c tumors and similar to T80/Akt tumors although slower than the tumors formed by SKOV3ip1 and T80/c-Myc cells. The average survival time for the mice with the i.p. implantations was about six months for T80/KLF8 as compared to approximately two months for SKOV3ip1. These novel findings suggest that KLF8 plays a critical oncogenic role in synergy with c-Myc in the ovarian cancer progression. The mouse tumor models generated in this work provide important tools for the studies of mechanisms underlying human ovarian cancer progression.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4306. doi:10.1158/1538-7445.AM2011-4306
Abstract 4309: Establishment of the chick chorioallantoic membrane (CAM) as an ex vivo model system to study mechanisms underlying epithelial ovarian tumour growth and metastasis
Authors: Reed Jason , Correa Rohann , Ramos-Valdes Yudith , Dinulescu Daniela M. , Vanderhyden Barbara C. , Lewis John D. , DiMattia Gabriel E. , Shepherd Trevor G.
Published: July 2012

Epithelial ovarian cancer (EOC) accounts for approximately 90% of all human ovarian malignancies. Unfortunately, 75% of EOC cases are not diagnosed until advanced stages when the tumour has metastasized, after which standard therapy is less effective. Therefore, it remains vital to directly study the molecular and cellular mechanisms contributing to EOC metastasis in an experimentally-tractable system. The chick chorioallantoic membrane (CAM) is a highly-vascularized tissue responsible for gas and nutrient exchange in the avian embryo, and has been used extensively to study angiogenesis and tumour formation by highly-aggressive cancer cell lines. Herein, we report that ascites-derived primary human EOC cells and established EOC cell lines readily form well-vascularized tumours on the chick CAM. To investigate this property further, we have generated GFP-expressing clones from the mouse ovarian tumour cell lines MOSE-RM (oncogenic Ras & Myc overexpression, SV40 TAg), MASC-2 (SV40 TAg), and 4306 (oncogenic Kras & Pten-null) which will facilitate visualization of tumour growth on the CAM as well as complementary studies in syngeneic mouse models for future studies. Xenografts of MOSE-RM and 4306 cell lines onto the surface of the chick CAM establish tumours that are significantly larger in mass and size compared with MASC-2 cells. Importantly, EOC tumours grown on the chick CAM are histologically identical to those arising within the peritoneal cavity. MOSE-RM and 4306 cell lines promote angiogenesis using HUVEC cells and the chick CAM, whereas MASC-2 cells lack this ability. Overall, these results demonstrate that EOC tumour growth on the chick CAM can be exploited as a highly amenable model system for studying late-stage EOC metastasis. Our findings also indicate that neo-vascularization is an obligatory process for establishment of secondary tumours; thus, we are currently investigating signaling pathways that impact primary human EOC tumour growth and angiogenesis using the chick CAM.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4309. doi:10.1158/1538-7445.AM2011-4309
Abstract 431: Laminin-511 regulates melanoma cell function and tumor growth
Authors: Tang Ling , Cui Tengjiao , Li Jie
Published: July 2012

Laminin family proteins are major non-collagenous components of basement membranes and have been found to be involved in modulating cell behavior. Laminin-511, composed of α5, β1, γ1 chains, is a major component of basement membrane of epithelia and blood vessels. Our lab has recently found increased expression of laminin-511 in malignant tumors. It has been found that tumor cells can synthesize and secrete laminin matrix to modify cellular environment and promote cell invasion. To explore the potential role of laminin-511 in melanoma, we blocked the expression of laminin-511 in human melanoma cell line SK-Mel-28 using RNA silencing strategy by transducing cells with lentiviral vector carrying laminin α5 chain specific shRNA (Lenti-Lα5 shRNA). Our data demonstrated that blocking the expression of laminin-511 significantly inhibited melanoma cell proliferation, attachment, migration and invasion in vitro, as well as tumor growth in vivo. In melanoma cells transduced with Lenti-Lα5 shRNA, compared with control melanoma cells, in cell proliferation analysis the total viable cells were 34.49% and 26.28% reduced on day 3 and day 5, respectively; in cell attachment assay the cell binding ability was decreased by 36.4%, 37.65% and 36.2% at 15, 30 and 60 minutes, respectively; in a chamber migration assay the cell migratory rate was dramatically down 90% at 24 hours; and in a Metrigel invasion assay the cell invasive capacity was markedly reduced by 89% at 24 hours. Furthermore, blocking laminin-511 expression significantly reduced tumor growth in vivo in nude mice. 18 tumors grew out of 20 injections with average volume 206 mm3 8 weeks post injection in cells tranduced with Lenti-Lα5 shRNA compared with 20 tumors out of 20 injections with average volume 590 mm3 in control cells. These findings revealed that laminin-511 plays important roles in melanoma cell function and tumor growth. In addition, our results strongly indicate laminin-511 a potential target for melanoma therapy.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 431. doi:10.1158/1538-7445.AM2011-431
Abstract 4311: Utilising the preclinical Vk*MYC model of multiple myeloma to rapidly and effectively screen novel therapies and their combinations
Authors: Matthews Geoffrey M. , Chesi Marta , Lefebure Marcus , Shortt Jake , Banks Kellie , Stanley Kym , Faulkner David , Atadja Peter , Bergsagel Leif , Johnstone Ricky W.
Published: July 2012

Introduction: Multiple myeloma (MM) is an incurable hematological neoplasm with an unmet need for novel therapeutic options. Here we employed the genetically tractable Vk*MYC murine model of MM to screen current and novel therapeutics in transgenic Vk*MYC mice and in transplant models of Vk*MYC MM. In addition to assessing single agent activity we also determined the effects of the histone-deacetylase inhibitor (HDACi) panobinostat (LBH-589) with the proteosome inhibitor bortezomib (Velcade) used in combination. Methods: Current and novel anti-MM agents (32) were screened in transgenic Vk*MYC mice (≥60wk) using clinically based regimens. Of these, panobinostat and bortezomib were shown to be the most efficacious and were selected to treat immunocompetent C57BL/6 mice bearing transplanted Vk*MYC MM (2 months post-transplant). Combination therapy was investigated in transplanted Vk*MYC MM consisting of low dose panobinostat (10mg/kg) with bortezomib (0.5mg/kg). Serum paraprotein levels were measured in all mice. Tumour load, drug targets and apoptosis were assessed by FACS or IHC staining of bone marrow sections. Results: Initial drug screening in Vk*MYC transgenic mice demonstrated anti-MM activity of panobinostat and bortezomib reflected by 50 and >25% reductions from baseline paraprotein levels, respectively. Similarly, serum paraprotein in C57BL/6 mice bearing Vk*MYC MM was significantly reduced with panobinostat (25mg/kg, 4d; 15mg/kg 5d/wk, 3wk) and bortezomib (0.5mg/kg, every 4d) alone compared with vehicle-treated mice. Moreover, panobinostat induced a significant survival advantage compared with vehicle (36.5d vs. 16d, p<0.01). Combination therapy using panobinostat and bortezomib at low doses reduced paraprotein significantly more than either agent alone. This was associated with histone-H3 acetylation, apoptosis induction and a reduction in viable plasma cells within bone marrow. Conclusions: These results suggest that panobinostat and bortezomib have single agent activity against MM and are the first to demonstrate therapeutic benefit in the pre-clinical Vk*MYC MM model. Moreover, combination therapies of panobinostat with proteosome inhibitors may be a rational approach for the treatment of MM. Future studies will investigate the molecular events underlying the single agent and combination effects of panobinostat and bortezomib using the Vk*MYC MM model.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4311. doi:10.1158/1538-7445.AM2011-4311
Abstract 4312: Loss of Ink4a and Arf each contributes to increased susceptibility to asbestos-induced malignant mesothelioma development
Authors: Altomare Deborah A. , Menges Craig W. , Xu Jinfei , Pei Jianming , Zhang Lili , Tadevosyan Ara , Neumann-Domer Erin , Liu Zemin , Carbone Michele , Chudoba Ilse , Klein-Szanto Andres J. , Testa Joseph R.
Published: July 2012

The CDKN2A/ARF locus encompasses overlapping tumor suppressor genes p16(INK4A) and p14(ARF), which are frequently co-deleted in human malignant mesothelioma (MM). The importance of p16(INK4A) loss in human cancer is well established, but the relative significance of p14(ARF) loss has been debated. The tumor predisposition of mice singly deficient for either Ink4a or Arf, due to targeting of exons 1α or 1β, respectively, supports the idea that both play significant and nonredundant roles in suppressing spontaneous tumors. To further test this notion, we exposed Ink4a(+/-) and Arf(+/-) mice to asbestos, the major cause of MM. Asbestos-treated Ink4a(+/-) and Arf(+/-) mice showed increased incidence and shorter latency of MM relative to wild-type littermates. MMs from Ink4a(+/-) mice exhibited biallelic inactivation of Ink4a, loss of Arf or p53 expression and frequent loss of p15(Ink4b). In contrast, MMs from Arf (+/-) mice exhibited loss of Arf expression, but did not require loss of Ink4a or Ink4b. Mice doubly deficient for Ink4a and Arf, due to deletion of Cdkn2a/Arf exon 2, showed accelerated asbestos-induced MM formation relative to mice deficient for Ink4a or Arf alone, and MMs exhibited biallelic loss of both tumor suppressor genes. The tumor suppressor function of Arf in MM was p53-independent, since MMs with loss of Arf retained functional p53. Collectively, these investigations provide in vivo evidence indicating that both CDKN2A/ARF gene products suppress asbestos carcinogenicity. Furthermore, while inactivation of ARF appears to be crucial for MM pathogenesis, the inactivation of both p16(INK4A) and p19(ARF) cooperate to accelerate asbestos-induced tumorigenesis.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4312. doi:10.1158/1538-7445.AM2011-4312
Abstract 4317: Low dose arsenic-induced transient p53 inhibition: A novel strategy for chemotherapy protection
Authors: Ganapathy Suthakar , Seog-Jin Seo , Ha Chul Soo , Yuan Zhi-Min
Published: July 2012

Because of its effectiveness in killing cancer cells, chemotherapy remains to be one of the common modalities for cancer treatment, but the resulting severe side effects often pose a significant threat to cancer patients. Recognizing p53 activation in the sensitive tissues as the primary mechanism for chemotherapy-induced acute toxicity and the universal p53 inactivation in human cancers, we exploited the use of low dose arsenic to inhibit p53 for a selective protection of normal tissues from chemotherapeutics-induced damages. Colon carcinoma cell line SW-480 was used to generate a mouse xenograft model. Treatments were initiated three weeks after implantation when the tumor size reached approximately 100 mm3. Arsenic pretreatment was carried out by feeding sex-matched mice (4-6 weeks of age) with water (1.0 mg/L) for three days. As expected, treatment of tumor-bearing mice with 5FU for 7 days resulted in 77% decrease in tumor volume when compared with the untreated group. The brief treatment with low doses of arsenic did not affect the ability of 5FU to induce tumor regression as evidenced by an 80% reduction of tumor size. However, arsenic treatment was associated with a marked alleviation of 5FU-induced systemic toxicity as demonstrated by the finding that arsenic pretreatment reduced 5FU-induced body weight loss from 25% to 4%. The protecting effect of arsenic was also clearly evident in reducing 5FU-induced damage in gastrointestinal (GI) track and hematopoietic (HP) system, two of the most sensitive tissues. Using mutant p53 expressing mice, we demonstrate that arsenic-mediated protection primarily depends on functional p53. Our preclinical study implicates that the brief use of low doses arsenic to inhibit p53 is an effective approach of chemotherapy protection. If successfully validated in clinical studies, this strategy may not only minimize side effects, but would also allow escalated therapeutic doses to improve treatment efficacy in a safe and effective approach for cancer therapy protection.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4317. doi:10.1158/1538-7445.AM2011-4317