bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 4883: CDK8: A new druggable mediator of NFκB activity
Authors: Chen Mengqian , McDermott Martina , Yang Zhengguan , Liang Jiaxin , Schools Gary P. , Lim Chang-uk , Lu Tao , George Stark R. , West Deborah K. , Porter Donald C. , Broude Eugenia V. , Roninson Igor B.
Published: May 2015

Cyclin-dependent kinase 8 (CDK8) is a transcription-regulating oncogenic serine kinase, which mediates several cancer-related transcriptional pathways such as beta-catenin, TP53, TGF-beta and HIF1A. We have recently discovered the first selective small-molecule inhibitors of CDK8 and its closely related isoform CDK19 and showed that these inhibitors block chemotherapy-induced tumor-promoting paracrine activities of both tumor and normal cells (Porter et al., PNAS 109, 13799, 2012). Since transcription factor NFκB plays a key role in damage-induced expression of tumor-promoting cytokines, we have tested the effects of a highly selective CDK8/19 inhibitor Senexin A on NFκB-induced transcription. Senexin A treatment or knockdown of CDK8 by shRNA inhibits transcriptional activation of NFκB-responsive promoters and of acutely responsive cytokine genes (such as CXCL1, CXCL2, IL8 and CCL20), by TNFα, a canonical NFκB activator, in several cell lines. CDK8 inhibition did not prevent nuclear translocation of active NFκB proteins. Chromatin immunoprecipitation (ChIP) analysis of HEK293 cells, untreated or treated with TNFα or Senexin A, singly or in combination, showed that CDK8 is recruited to NFκB early-responsive genes upon TNFα treatment, but the CDK8 inhibitor did not prevent the recruitment of NFκB, CDK8 or RNA Polymerase II (Pol II) to the target genes. However, CDK8 kinase activity was found to be required for C-terminal domain phosphorylation (both at S2 and S5 residues) of Pol II associated with the target genes, which is needed for the elongation of their NFκB-initiated transcription. In contrast, Pol II phosphorylation at constitutively expressed genes is not dependent on CDK8 kinase activity. These results suggest that CDK8 inhibitors may exert their effects against the activation of tumor-promoting and pro-inflammatory secreted factors in the tumor microenvironment by preventing transcriptional activation of NFκB-induced genes.

Citation Format: Mengqian Chen, Martina McDermott, Zhengguan Yang, Jiaxin Liang, Gary P. Schools, Chang-uk Lim, Tao Lu, Stark R. George, Deborah K. West, Donald C. Porter, Eugenia V. Broude, Igor B. Roninson. CDK8: A new druggable mediator of NFκB activity. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4883. doi:10.1158/1538-7445.AM2014-4883
Abstract 4888: The novel cytokine IL-17D at the intersection of cellular stress and tumor immunity
Authors: Saddawi-Konefka Robert , Bui Jack
Published: May 2015

Our laboratory has recently identified a novel role for the cytokine IL-17D as an important mediator of the antitumor immune response; and, the loss of IL-17D as a key component of tumor progression. Our data show for the first time that overexpression of the cytokine IL-17D is sufficient to induce tumor rejection or growth delay. Tumors expressing IL-17D displayed an increased infiltration of natural killer (NK) cells, which gave way to a commensurate increase of M1-type macrophages. While examining the regulation of IL-17D, we came across the surprising finding that IL-17D can be induced by oxidative stress signals via the transcription factor nrf2. Nrf2, responsible for regulating the expression of the anti-oxidant response element genes, is known as the primary cellular responder to oxidative stress. Although the role of nrf2 in cancer biology has been well studied, the role of nrf2 in the regulation of immune responses (particularly via IL-17D) has yet to be defined. We find that nrf2 is necessary to induce IL-17D expression in a variety of tumor and non-tumor cells, and that this regulation is active in tumor progression. These studies constitute an intriguing and novel connection between oxidative cellular stress and immune activation.

Citation Format: Robert Saddawi-Konefka, Jack Bui. The novel cytokine IL-17D at the intersection of cellular stress and tumor immunity. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4888. doi:10.1158/1538-7445.AM2014-4888
Abstract 489: Hypoxia-mediated ROS enhances HGF-induced cancer cell invasion and suppresses cell cycle progression
Authors: Lee Young H. , Bottaro Donald P.
Published: May 2015

The cellular response to hypoxia is a major influence on the aggressiveness of primary tumors, yet much of how this response mechanism influences other signaling pathways is unknown. The MET proto-oncogene, which encodes the tyrosine kinase receptor for hepatocyte growth factor (HGF), is often overexpressed in cancers and can drive cell proliferation, invasion, and metastasis. Prior studies demonstrated that the Met tyrosine-kinase receptor drives cell invasion and metastasis under hypoxic conditions, and this invasive phenotype is lost if MET expression is suppressed. Hypoxia also has been shown to sensitize HGF driven invasion through an as yet undefined molecular mechanism. The high mortality rate of metastatic cancer makes it crucial to understand the functional integration of these two prevalent drivers of metastasis, hypoxia and Met signaling, and to identify ways to selectively block cancer cell invasiveness. We show that hypoxia enhanced HGF-mediated invasion in the papillary renal cell (PRC) carcinoma cell lines ACHN and UOK112. Cells under hypoxic conditions accumulated high levels of ROS, which in turn sensitized the Erk pathway to enhance HGF-driven invasion. ROS accumulation was also associated with suppression of MAPK phosphatase DUSP2 mRNA. The other prevalent arm of Met mediated signaling, the PI3K/Akt pathway, normally drives cell survival and proliferation. In hypoxic conditions, however, Akt activation is suppressed by ROS mediated PP2a activation. This is accompanied by metabolic shift towards autophagy and decreased cell cycle progression. Thus hypoxia modifies HGF biologic program by enhancing invasion and suppressing proliferation. Identifying the specific effectors responsible for the integration these signaling pathways will improve our understanding of pro-metastatic invasiveness and potentially identify novels targets for its selective blockade.

Citation Format: Young H. Lee, Donald P. Bottaro. Hypoxia-mediated ROS enhances HGF-induced cancer cell invasion and suppresses cell cycle progression. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 489. doi:10.1158/1538-7445.AM2014-489
Abstract 4890: Collagen 1 fibers are a key component in the establishment of distant pulmonary metastasis by breast cancer cells
Authors: Jacob Desmond , Kakkad Samata M. , Krishnamachary Balaji , Stasinopoulos Ioannis , Solaiyappan Meiyappan , Wildes Flonne , Glunde Kristine , Bhujwalla Zaver M.
Published: May 2015

We previously observed that silencing COX-2 significantly reduced the expression of degradative enzymes such as matrix metalloproteinase 1 (MMP1), and altered the expression of ECM components such as hyaluronan and lumican that play a role in intra-fibrillar collagen spacing [1]. We have also observed that primary human breast cancers that have metastasized have higher collagen 1 (Col1) fiber density and volume [2]. Here, for the first time, we have investigated Col1 fiber patterns in metastatic lung nodules established by metastatic MDA-MB-231 breast cancer cells and their subclone Clone 13 cells that express shRNA to significantly reduce, but not silence, COX-2 expression.

Second harmonic generation (SHG) microscopy studies were performed on H&E stained lung sections obtained from SCID mice five weeks post intravenous injection of MDA-MB-231 (five mice) and Clone 13 (three mice) human breast cancer cells. SHG images of 5-7 fields of view per mouse were acquired from the lung sections on an Olympus FV1000MPE multiphoton microscope, and analyzed for inter-fiber distance and percentage of fiber per metastatic area using in-house software [2]. Reducing COX-2 expression resulted in a significant reduction of metastatic lung burden in mice. Analysis of the Col1 fiber structures of similar sized metastatic nodules revealed significantly fewer fibers and larger inter fiber distance in lung nodules of mice injected with Clone 13 cells compared to parental MDA-MB-231 cells.

Reducing COX-2 resulted in the establishment of significantly fewer metastatic lung nodules with significantly sparser Col1 fibers. These data suggest that the ability to lay down Col1 fibers is a key requirement for the successful establishment of metastatic lesions. Reducing COX-2 expression in MDA-MB-231 breast cancer cells affects the ability of these cancer cells to lay down a Col1 fiber scaffold suitable for cancer cell growth in the lungs. These data identify new aspects of the role of Col1 fibers and COX-2 in the establishment of metastatic lesions.

References: [1] I. Stasinopoulos et al., Neoplasia (2008); [2] S. Kakkad et al., J Biomed Opt (2012).

This work was supported by NIH R01CA82337 and P50CA103175.

Citation Format: Desmond Jacob, Samata M. Kakkad, Balaji Krishnamachary, Ioannis Stasinopoulos, Meiyappan Solaiyappan, Flonne Wildes, Kristine Glunde, Zaver M. Bhujwalla. Collagen 1 fibers are a key component in the establishment of distant pulmonary metastasis by breast cancer cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4890. doi:10.1158/1538-7445.AM2014-4890
Abstract 4894: The HSP90 inhibitor ganetespib potentiates effect of ionizing radiation in human non-small cell lung cancer
Authors: Casal Roberto Gomez , Bhattacharya Chitralekha , Epperly Michael , Socinski Mark , Levina Vera
Published: May 2015

Background: Ionizing irradiation (IR) is used to treat NSCLC however; radiotherapy remains largely palliative due to radioresistance.

Recently, we reported that IR-resistant residual cells in NSCLC expresses a complex phenotype combining cancer stem cell (CSC) and the epithelial to mesenchymal transition (EMT) traits. The tyrosine kinase receptors (RTK) receptors, such as PDGFRa, EGFR FGFR and VEGFR, are expressed in nonrelated cells and IR-resistant residual cells. Moreover, PDGFRb is dramatically upregulated in IR resistant cells. Since all of these RTK receptors, as well as other oncogenic proteins are client proteins of the molecular chaperone HSP90a, NSCLC cells and specifically IR-resistant residual cells could be highly dependent on HSP90 and sensitive to HSP90 inhibition.

We hypothesize that inhibition of HSP90 will eliminate IR-resistant residual cells and sensitize NSCLC cells to IR treatment.

Methods/Results: HSP90 inhibitor Ganetespib, kindly provided by SYNTA Pharmaceuticals, was used in this study. A549 cells, primary human adenocarcinoma cells and primary normal human airway epithelial (HSAEC), were utilized. Using MTT and clonogenic assays we have demonstrated that ganetespib does not affect primary normal HSAEC cells, but suppresses the proliferation of NSCLC cells and potentiates the effect of IR treatment. Ganetespib inhibits the growth of lung tumor spheres. Using a wound healing assay we have determined that ganetespib inhibits motility of NSCLC cells and IR-resistant residual cells. We also have investigated the effect of ganetespib on cells cycle, apoptosis and DNA repair machinery in irradiated cells. Using a SCID mice model, we have demonstrated that ganetespib applied as monotherapy inhibits the growth of T2821 primary adenocarcinoma cells in vivo and significantly sensitizes T2821 tumors to IR-treatment.

Conclusion: The HSP90 inhibitor ganetespib potentiates the effect of IR in NSCLC and eliminates IR-resistant residual cells.

Note: This abstract was not presented at the meeting.

Citation Format: Roberto Gomez Casal, Chitralekha Bhattacharya, Michael Epperly, Mark Socinski, Vera Levina. The HSP90 inhibitor ganetespib potentiates effect of ionizing radiation in human non-small cell lung cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4894. doi:10.1158/1538-7445.AM2014-4894
Abstract 49: Zinc finger protein 185 is a key molecule of liver metastasis in colon cancer
Authors: Furukawa Daisuke , Chijiwa Tsuyoshi , Matsuyama Masahiro , Mukai Masaya , Matsuo Ei-ichi , Nishimura Osamu , Kawai Kenji , Suemizu Hiroshi , Hiraoka Nobuyoshi , Nakagohri Toshio , Yasuda Seiei , Nakamura Masato
Published: May 2015

Colorectal cancer is among the three leading causes of cancer-related deaths worldwide. Nearly 50% of patients with colon cancer develop liver metastases. Mortality associated with the advanced stage of colon cancer has principally been attributed to the development of liver metastases. Therefore, clarifying the biological mechanisms underlying liver metastasis from colon cancer and accelerating the development of new treatment strategies are needed. We isolated Zinc finger protein 185 (ZNF185) as a metastasis-related protein by global quantitative proteome analysis of the in vivo liver metastasis model of super immunodeficient NOG mice with the highly liver-metastatic subline SW48-LM2 (Matsuo E, et al. AACR, #3947, 2008). LIM domain proteins have many fundamental biological processes including cell lineage specification, cytoskeleton organization, and organ development. ZNF185 is one of the LIM domain proteins and is considered to be involved in regulating cellular differentiation and/or proliferation. However, the functions and properties of ZNF185 in the multi-step process of cancer biology have not yet been elucidated in detail. In the present study, we analyzed the relationships between ZNF185 and the clinicopathological features of colon cancer (age, gender, histological type, lymphatic involvement, venous involvement, T and N statuses, liver metastasis, and stage). The expression of the ZNF185 protein was immunohistochemically analyzed. The expression of ZNF185 was detected in the cancer cells of 78 of 87 colon cancer patients. A correlation was observed between ZNF185 and the histological type (p=0.010, G-test). The expression of ZNF185 was also correlated with liver metastasis (p=0.030, G-test). Multivariate analysis using the Cox proportional hazards model was performed among the cause-specific survival rate, ZNF185 expression, and clinicopathological features. The histological type, liver metastasis, and ZNF185 expression were found to be independent prognostic indicators (p= 0.028, p<0.0001, p=0.036, respectively). ZNF185 expression was found to be an independent indicator of liver metastasis and prognosis in colon cancer.

Citation Format: Daisuke Furukawa, Tsuyoshi Chijiwa, Masahiro Matsuyama, Masaya Mukai, Ei-ichi Matsuo, Osamu Nishimura, Kenji Kawai, Hiroshi Suemizu, Nobuyoshi Hiraoka, Toshio Nakagohri, Seiei Yasuda, Masato Nakamura. Zinc finger protein 185 is a key molecule of liver metastasis in colon cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 49. doi:10.1158/1538-7445.AM2014-49
Abstract 490: Investigation of telomere shortening caused by dyskeratosis congenita-associated heterozygous TIN2 mutations
Authors: Tran Duy C. , Frank Amanda K. , Xu Lifeng
Published: May 2015

The ends of eukaryotic chromosomes are composed of repetitive telomere sequences bound by the shelterin protein complex. Telomerase, a reverse transcriptase complex, is known to express in highly proliferative tissues and cells in humans to maintain a constant telomere length and to sustain their proliferative potential. Heterozygous missense mutations within one of the shelterin proteins, TIN2, have been identified in patients with Dyskeratosis Congenita (DC), a multiple stem-cell failure syndrome characterized by extremely short telomeres in affected patients. Our study aims to elucidate the mechanism by which TIN2 mutations shorten telomeres in human cells.

TIN2 is an essential protein that tethers the shelterin complex together. We generated HCT 116 colorectal cancer cell lines containing heterozygous TIN2 R282H mutation, one of the most common DC-related TIN2 mutations, by zinc-finger-nuclease facilitated gene editing. Clones with heterozygous TIN2 mutation showed progressive telomere shortening, while the wild-type (WT) clones showed no change in telomere length over extended cell proliferation. The progressive telomere shortening phenotype in TIN2 mutants can be rescued by exogenous expression of WT TIN2. However, TIN2 mutant clones do not contain elevated levels of deprotected telomeres, suggesting that the TIN2 mutation does not lead to overall telomere deprotection. We are currently investigating whether the DC-related TIN2 mutation induces telomere shortening by inhibiting telomerase or by accelerating telomere attrition through telomerase-independent mechanisms.

Citation Format: Duy C. Tran, Amanda K. Frank, Lifeng Xu. Investigation of telomere shortening caused by dyskeratosis congenita-associated heterozygous TIN2 mutations. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 490. doi:10.1158/1538-7445.AM2014-490
Abstract 4903: Luteolin's role as a radiosensitizer by promoting cell death and ROS modulation
Authors: Ahn Kwang-Chul , Choi Jae Yeon , Hwang Sang-Gu , Um Hong-Duck , Park Jong Kuk
Published: May 2015

Radiotherapy is one of major cancer treatment, but radiation treatment could evoke resistance or side effects such as fibrosis. To overcome these obstacles against radiation treatment, many researchers are developing effective radiosensitizer. To develop a new radiosensitizer, we test whether luteolin has functions as a radiosensitizer candidate because previous studies already demonstrated luteolin could promote cancer cell death by reactive oxygen species (ROS) induction, and this phenomenon is one of main effects of radiation-induced cell death. Luteolin is 3′,4′,5,7-tetrahydroxyflavone, which could induce cell death of various cancer cells. We observed luteolin treatment could induce cell death of non-small cell lung cancer cells with independent manner of p53 and PTEN status, and combination treatment of radiation and luteolin enhance more cell death than those of radiation only or luteolin only treatment condition. Dose enhancement ratios of luteolin and radiation combination are 1.54 and 1.31 in NCI-H460 and NCI-H1299, respectively. Combined treatment with luteolin and radiation down-regulate Bcl-2 level and induce the phosphorylation of JNK and activation of caspase-3/9. ROS accumulation also was induced in combined condition of luteolin and radiations. In a xenograft assay, the combined luteolin and radiation group showed 27.2 days of growth delay versus the control in terms of tumor growth. The enhancement factor of this combined treatment was determined to be 3.2. Taken together, we conclude that luteolin contain role of radiosensitizer via promotion of cell death and ROS accumulation.

Citation Format: Kwang-Chul Ahn, Jae Yeon Choi, Sang-Gu Hwang, Hong-Duck Um, Jong Kuk Park. Luteolin's role as a radiosensitizer by promoting cell death and ROS modulation. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4903. doi:10.1158/1538-7445.AM2014-4903
Abstract 492: Hepatic oxidative stress activates the Gadd45b gene via degradation of the transcriptional repressor STAT3
Authors: Kim Jung-Hwan , Qu Aijuan , Reddy Janardan K. , Gao Bin , Gonzalez Frank J.
Published: May 2015

Growth arrest and DNA damage-inducible beta (GADD45b) plays an important role in many intracellular events, such as cell cycle arrest, DNA repair, cell survival, apoptosis, and senescence. However, its mechanism of transcriptional regulation remains unclear. In this study the mechanism of proliferator-activated receptor a (PPARa) ligand induction of the Gadd45b gene in mouse liver was investigated. Gadd45b messenger RNA (mRNA) was markedly induced by the PPARa agonist, Wy-14,643, in wild-type mice but not in Ppara-null mice. Signal transducer and activator of transcription 3 (STAT3) was found to be a repressor of the Gadd45b gene through binding to upstream regulatory elements. The role of STAT3 in control of Gadd45b was confirmed using liverspecific Stat3-null mice. Wy-14,643 treatment stimulated STAT3 ubiquitination leading to activation of the Gadd45b gene as a result of loss of Gadd45b repression by STAT3.

STAT3 degradation was induced by forced overexpression of the PPARa target geneencoded enzyme ACOX1, which produces increased H2O2 as a byproduct of fatty acid b-oxidation. H2O2 also stimulated expression of Gadd45b in cultured cells. In conclusion, these studies revealed that PPARa indirectly induces the Gadd45b gene in liver through promoting degradation of the repressor STAT3 as a result of elevated oxidative stress.

Note: This abstract was not presented at the meeting.

Citation Format: Jung-Hwan Kim, Aijuan Qu, Janardan K. Reddy, Bin Gao, Frank J. Gonzalez. Hepatic oxidative stress activates the Gadd45b gene via degradation of the transcriptional repressor STAT3. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 492. doi:10.1158/1538-7445.AM2014-492
Abstract 4921: X-ray irradiation induced bio luminescence: Ex vivo and endoscopic imaging of radiobioluminescence
Authors: Papineni Rao V.
Published: May 2015

Accurate dose delivery to malignant tissue in radiotherapy is essential for enhancing the treatment efficacy while minimizing morbidity of surrounding normal tissues. Advances in therapeutic strategies and diagnosis technologies along with our understanding of the biology of tumor response to radiation therapy have paved way to allow nearly 60% of current cancer patients to be treated with Radiation Therapy. The confluence of molecular imaging and nanotechnology fields are bridging physics and medicine and are quickly making strides in opening new avenues and therapeutic strategies that complement radiation therapy- with a distinct footprint in immunotherapy, adoptive cell therapy, and targeted chemotherapy. Incorporating optical imaging in radiation therapy in my laboratory, endogenous bioluminescence resulting from whole body irradiation in different organs, which is distinct from the cherenkov radiation, is described here. Mice were subjected to 5 - 10 Gy X-ray irradiation doses using commercially available X-RAD 320 irradiator (1Gy/min; F2 beam hardening filter 1.5mm Al, 0.25mm Cu, 0.75mm Sn; Precision X-ray inc, USA). The endogenous bioluminescence in response to irradiation, described here as radiobioluminescence, was captured using cooled CCD camera from live subjects, and from the excised organs/tissues. Significant increase (up to 100 fold) in the amounts of photons released as bioluminescence was detected during 5 -10 min capture from the mice subjected to irradiation compared to that of the control. The GI tract contributed significant portion of this radiobioluminescence and was confirmed both by ex-vivo and minimally invasive rectal endoscopic imaging. Other organs and tissues displaying such robust increase in radiobioluminescence include skin, and fat depots. The role, evaluation, and future assessment of nutrients, nutriceuticals, microbiome, and metabolites during the course of radiation therapy become highlighted with these findings. Thus such molecular imaging methodologies and modalities described will be useful tools in radiation treatment design and process.

Citation Format: Rao V. Papineni. X-ray irradiation induced bio luminescence: Ex vivo and endoscopic imaging of radiobioluminescence. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4921. doi:10.1158/1538-7445.AM2014-4921
Abstract 4930: Quantitative PET imaging of tissue factor expression using 18F-labeled active site inhibited factor VIIa
Authors: Nielsen Carsten H. , Erlandsson Maria , Jensen Mette M. , Madsen Jacob , Petersen Lars C. , Kjaer Andreas
Published: May 2015

Objectives: Tissue factor (TF) is up regulated in many solid tumors and its expression is linked to tumor angiogenesis, invasion, metastasis and prognosis. Hence it would be of clinical relevance if one could assess tumor TF expression status non-invasively. Here we report the development of a new PET tracer for specific imaging of TF using a derivative of factor VII, the natural ligand to TF, labeled with 18F.

Methods: Active site inhibited factor VIIa (ASIS) was radiolabeled with N-succinimidyl 4-18F-fluorobenzoate ([18F]SFB) and purified. Nude mice (n=5) with subcutaneous human pancreatic xenograft tumors (BxPC-3) underwent small animal PET/CT imaging 1, 2 and 4 hours after injection of 7.3-9.3 MBq [18F]ASIS (∼37 µg) in 160 µL saline. Mice were euthanized following the last imaging session, and their tumors and major organs were resected for ex vivo gamma well counting. Tumor tissue was preserved for molecular analysis. A blocking experiment was performed in a second set of mice. The blocking group (n=3) received 500 µg non-labeled ASIS before injection of [18F]ASIS and was imaged after 4 hours. The expression pattern of TF in the tumors was visualized by immunohistochemistry and the amount of TF in tumor homogenates was measured by ELISA.

Results: The PET images showed high uptake of [18F]ASIS in the tumor regions with a mean uptake of 2.40 ±0.18, 2.56 ±0.20 and 2.54 ±0.27 %ID/g (Mean ±SEM) at 1, 2 and 4 hours after injection of [18F]ASIS and with an average maximum uptake in the tumors of 7.08 ±0.72 %ID/g at 4 hours. In comparison, the muscle uptake was 0.19 ±0.01 %ID/g at 4 hours. At 4 hours the tumors had the highest uptake of any organ. Blocking with cold ASIS significantly reduced the uptake of [18F]ASIS from 2.51 ±0.06 to 1.29 ±0.07 %ID/g (p<0.001). Importantly, the uptake of [18F]ASIS measured in vivo by PET imaging correlated (r=0.72, p<0.02) with TF expression at the protein level measured ex vivo in tumor homogenates by ELISA.

Conclusion: PET/CT imaging with [18F]ASIS can be used for specific, non-invasive imaging of TF expression.

Research Support: This work was supported by at grant from the Danish National Advanced Technology Foundation.

Citation Format: Carsten H. Nielsen, Maria Erlandsson, Mette M. Jensen, Jacob Madsen, Lars C. Petersen, Andreas Kjaer. Quantitative PET imaging of tissue factor expression using 18F-labeled active site inhibited factor VIIa. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4930. doi:10.1158/1538-7445.AM2014-4930
Abstract 4954: Hematogenous metastasis of ovarian cancer: Re-thinking mode of spread
Authors: Pradeep Sunila , Kim Seung Wook , Wu Sherry , Masato Nishimuara , Miyake Takahito , Hyun-Jin Choi , Rupaimoole Rajesha , Liu Jinsong , Fidler Isahai , Lopez Gabriel , Sood Anil
Published: May 2015

Background: Most patients with ovarian cancer have widely metastatic disease within the abdominal cavity at primary diagnosis; historically, this was thought to occur via intraperitoneal “seeding”. Here, we report unexpected findings related to hematogenous ovarian cancer metastasis with a strong tropism for the omentum.

Methods: We established a novel parabiosis model where the skin of female mice was fused surgically from the shoulder to the hip joint. Two weeks later, the “host” parabiont mice were injected with tumor cells into ovary. Once the host mice became moribund, the parabionts were separated, and the host mice were euthanized. Tumor development and patterns of metastasis were analyzed in the host mice. A series of additional in vitro and in vivo experiments were carried out to decipher the underlying mechanisms.

Results: The parabiosis models demonstrated that tumor cells injected into the ovary of each “host” mouse metastasized to the corresponding “guest” mouse, predominantly to the omentum. Using high-throughput transcriptome analysis and phospho-proteome arrays, we demonstrated that ErbB3, an EGFR family receptor tyrosine kinase (RTK) was highly expressed in the ovarian cancer cells that hematogenously metastasized to the omentum (SKOV3-OM3) compared to parental cells. The ErbB3-NRG1 axis activated Src/PI3K/AKT signaling pathway, which in turn induced loss of polarity and increased invasion of ovarian cancer cells. Depletion of murine NRG1 using target specific siRNAs almost completely abolished omental metastasis. In contrast, overexpression of ErbB3 resulted in enhanced tumor formation and omental metastatic spread, which confirms the role of ErbB3 in hematogenous omental metastasis. Additional studies with a function-blocking antibody specific to ErbB3 led to substantial reduction in hematogenous metastasis of ovarian cancer cells.

Conclusions:

Collectively, our results provide the first evidence that ovarian cancer cells are capable of hematogenous metastasis, but with strong tropism for the omentum. These findings not only provide a new understanding of ovarian cancer metastasis, but also identify novel therapeutic targets.

Citation Format: Sunila Pradeep, Seung Wook Kim, Sherry Wu, Nishimuara Masato, Takahito Miyake, Choi Hyun-Jin, Rajesha Rupaimoole, Jinsong Liu, Isahai Fidler, Gabriel Lopez, Anil Sood. Hematogenous metastasis of ovarian cancer: Re-thinking mode of spread. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4954. doi:10.1158/1538-7445.AM2014-4954
Abstract 4955: Role of Angiotensin II in prostate cancer metastasis
Authors: Chakroborty Debanjan , Sarkar Chandrani
Published: May 2015

Introduction: At the initial stages prostate cancer development depends on a crucial level of androgenic stimulation but at later stages when it becomes androgen independent the perturbation from androgen receptor axis leads to the development of more aggressive phenotypes with greater metastatic potential. At this stage the growth and progression of prostate cancer is regulated by various local growth factors and neuro-hormones which are altered in prostate cancer microenvironment. Therefore, identifying these factors which are aberrantly expressed in the tumor microenvironment and understanding how these factors are involved in regulating the tumor progression are essential for developing better targeted therapeutic strategy for the treatment of advanced stages of prostate cancer.

Objective: As emerging reports suggest the importance of tissue based renin angiotensin system (RAS) in pathophysiology of the prostate and as studies indicate a lower incidence of cancer and cancer related deaths in patients taking angiotensin receptor blockers (ARBs) (as medication for hypertension), we intend to study the role played by this system in the progression of prostate cancer.

Methods and Results: Our results show that there is limited expression of RAS components, Angiotensin II (AT II), the main bioactive effector peptide of RAS and its receptors, and its receptor Angiotensin receptor type 1( AT1R) and Angiotensin receptor type 2 (AT2R) , in mouse prostate tissues. However, RAS becomes activated in prostate cancer. The expressions of ATII and AT1R are significantly higher in androgen independent orthotopic PC3 prostate tumor tissues. The expression of AT2R remains unaltered during the development of tumor. Therefore to evaluate the role of ATII in prostate cancer progression, in vitro experiments using two androgen independent orthotopic cell lines, PC3 and C4-2 were performed. Both these cell lines express AT1R. Our results indicate that ATII acting through AT1R promotes metastatic behavior such as invasion and migration of prostate cancer cells and inhibition of ATII by blocking AT1R receptor abrogates this action of ATII.

Conclusions: This study identifies a new role of local RAS in the metastatic progression of prostate cancer and will eventually help to develop newer and effective therapeutic strategies in treatment of androgen independent prostate cancer by targeting ATII or AT1R. This strategy can be used either alone or in combination with existing therapeutic strategies in treatment of the disease.

Citation Format: Debanjan Chakroborty, Chandrani Sarkar. Role of Angiotensin II in prostate cancer metastasis. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4955. doi:10.1158/1538-7445.AM2014-4955
Abstract 4957: Role of tumor-derived exosomes in growth and metastasis of breast cancer
Authors: Munagala Radha , Gupta Ramesh
Published: May 2015

Breast cancer (BC) mortality rates have decreased over last 30 years, largely due to early detection and improved treatment modalities, particularly targeted therapies. However, metastasis relentlessly drives mortality. The pervasive mortality from metastasis highlights the shortcomings of traditionally accepted hypotheses on the metastatic process. The mechanisms by which malignant tumors leave the primary tumor site, invade lymphatics, and metastasize to regional lymph nodes are complex and interrelated. Exosomes are biological nanovesicles (∼30-100 nm) of endocytic origin. Exosomes mediate local and horizontal transfer of information, such as mRNAs, miRNAs and proteins. They are indicated to play a significant role in the genesis of tumor, growth and metastasis. Recent advances in the exosome biology suggest that tumor-derived exosomes (TDEs) are critical mediators of tumorigenesis and can incite a pro-angiogenic signaling program capable of remodeling tissue matrices. However, the role of TDEs in BC metastasis remains elusive. In this study, we examined the role of exosomes in breast cancer metastasis using cell culture studies. We made the following observations: i) exosomes derived from BC cells had a mean size of 92 nm and carried exosomal marker proteins CD63 and CD81, ii) uptake of exosomes from highly metastatic BC cells (MDA-MB-231) by non-metastatic recipient cells (BT474 and T47D), iii) faster wound healing rate, increased migratory behavior, and invasiveness in recipient cells treated with metastatic BC exosomes, iv) increased endothelial cell tube formation, reflective of angiogenesis ability with exosomes from metastatic BC cells, v) modulation in expression levels of key EMT-associated proteins in non-metastatic cells treated with metastatic BC exosomes favoring EMT shift, vi) difference in metastasis-associated miRNAs levels in exosomes from invasive and non-invasive BC cells. Our data that suggest exosomes from metastatic BC cells carry the cargo essential for EMT and have the ability to change phenotypic traits of the recipient cells. Determining the role of exosomes in BC metastasis and characterization of BC exosomes components (proteins, mRNA and miRNA) will have great potential to uncover new targets and lead to new therapies for metastatic disease.

Citation Format: Radha Munagala, Ramesh Gupta. Role of tumor-derived exosomes in growth and metastasis of breast cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4957. doi:10.1158/1538-7445.AM2014-4957
Abstract 4963: In vivo and in vitro effect of a nutrient mixture on murine 4T1 breast cancer
Authors: Roomi M. Waheed , Cha John , Roomi Nusrath , Niedzwiecki Aleksandra , Rath Matthias
Published: May 2015

Breast cancer patients often have detectable or occult metastases at diagnosis and most patients will develop metastatic lesions during the course of the disease. We investigated the effect of a nutrient mixture (NM) containing ascorbic acid, lysine, proline, and green tea extract on murine breast cancer 4T1, a unique metastatic breast cancer model that has the capacity to metastasize efficiently to sites affected in human breast cancer. After one week of isolation, 5-6 week old female Balb/C mice were inoculated with 5x105 4T1 cells into the mammary pad and randomly divided into two groups; group A was fed a regular diet and group B a regular diet supplemented with 0.5% NM. After four weeks, the mice were sacrificed and their tumors, lungs, livers, kidneys, hearts and spleens were excised and processed for histology. Dimensions (length and width) of tumors were measured using a digital caliper, and the tumor burden was calculated using the following formula: 0.5 x length x width. We also tested the effect of NM in vitro on 4T1 cells, measuring cell proliferation by MTT assay, MMP secretion by zymography, invasion through Matrigel , migration by scratch test and morphology by H&E staining. NM inhibited tumor weight and burden of 4T1 tumors by 50% (p =0.02) and 53.4% (p<0.0001), respectively. Lung metastasis was profoundly inhibited by NM supplementation: mean number of colonies was reduced by 87% (p<0.0001) and mean weight of lungs by 60% (p=0.0001) compared to control mice. Metastasis to liver, spleen, kidney and heart was significantly reduced with NM supplementation. In vitro, NM exhibited 50% toxicity over the control at 250 and 500 µg/ml concentrations. Zymography demonstrated MMP-2 and MMP-9 secretion which was inhibited by NM in a dose dependent fashion, with virtual total inhibition of both at 1000 µg/ml. Migration by scratch test and Invasion through Matrigel were inhibited in a dose dependent manner with total block of invasion at 250 µg/ml and of migration at 1000 µg/ml. These results suggest that NM has therapeutic potential in treatment of breast cancer.

Citation Format: M. Waheed Roomi, John Cha, Nusrath Roomi, Aleksandra Niedzwiecki, Matthias Rath. In vivo and in vitro effect of a nutrient mixture on murine 4T1 breast cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4963. doi:10.1158/1538-7445.AM2014-4963
Abstract 4971: Splicing factor kinase regulates metastatic dissemination of human prostate cancer
Authors: Bond David J. , Stoletov Konstantin , Leong Hon Sing , Woolner Emma , Liu Shuhong , Bismar Tarek , Zijlstra Andries , Lewis John D.
Published: May 2015

Metastasis causes the vast majority of cancer-associated deaths. Despite its clinical significance, the molecular mechanisms that regulate this multi-step process are poorly understood. To successfully disseminate a cancer cell must escape the primary tumor, travel to a distant site, arrest, enter the stroma and grow in a new microenvironment. The presence of circulating tumor cells in patients with metastatic disease and experimental animals with metastatic cancers suggests that tumor invasion is a critical, rate-limiting step in the metastatic process. To identify the key molecular determinants that regulate invasive metastatic lesion formation we performed the first whole-genome, in vivo RNAi screen in an avian embryo model using advanced intravital imaging techniques. We identified numerous novel regulators of cancer cell invasion, including JL1, a splicing factor kinase.

In secondary assays, we demonstrated that JL1-depletion inhibits migration of several human cancer cell lines with no effect on proliferation or survival. Furthermore, JL1-deficient human cancer cells display diminished metastatic potential in chicken embryo and mouse models of metastasis. Cancer microarray database mining shows that JL1 gene expression is strongly associated with indicators of poor clinical outcome in prostate cancer, including pathological Gleason score and metastasis. To experimentally determine JL1 association with advanced disease we performed histological examinations of prostate cancer tissue and determined that JL1 staining strongly correlates with prostate cancer progression. JL1 kinase regulates alternative splicing of numerous cellular transcripts in response to stress and growth signals. To examine the molecular mechanism behind JL1 regulation of cancer cell metastasis, we performed exon level microarray analysis on JL1-depleted cancer cell lines. Subsequent interactome analysis identified an enrichment of key regulatory proteins in pro-metastatic networks. Therefore, we hypothesize that abrogated JL1 activity directly promotes prostate cancer cell migration and invasion. In summary, JL1 is a novel regulator of cancer cell metastasis that represents a potential pathological marker for prostate cancer progression, and novel drug target to block invasion and metastasis.

Citation Format: David J. Bond, Konstantin Stoletov, Hon Sing Leong, Emma Woolner, Shuhong Liu, Tarek Bismar, Andries Zijlstra, John D. Lewis. Splicing factor kinase regulates metastatic dissemination of human prostate cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4971. doi:10.1158/1538-7445.AM2014-4971
Abstract 4984: Contribution of MMP13 to tumor development in the steatotic liver microenvironment
Authors: Mendonsa Alisha Maria , VanSaun Michael N. , Gorden Lee
Published: May 2015

With the rising prevalence of obesity there has been a marked increase in the incidence of non alcoholic fatty liver disease (NAFLD). Epidemiologically, NAFLD has been linked to an increased risk for development of primary liver cancer (HCC), however the mechanisms involved are not known. The liver is also a frequent site of metastasis for several types of cancers. To determine the effect of steatosis (fatty liver) on tumor metastasis to the liver, we used a mouse model of diet induced steatosis coupled with the splenic injection model of metastasis to the liver and found a significant increase in the number of tumors in the steatotic livers. To evaluate what molecular changes distinguish the steatotic liver from normal liver, microarray analysis was performed and demonstrated that MMP13, a member of the Matrix Metalloproteinase family recognized to be involved in liver disease and cancer progression, is significantly upregulated in the steatotic liver compared to normal livers of mice. We evaluated MMP13 expression in human patients with NAFLD and found that MMP13 is elevated with the progression of NAFLD. We hypothesize that increased MMP13 levels in the steatotic liver contribute to a more permissive microenvironment for the establishment of liver tumors. To test this hypothesis, mice genetically deficient in MMP13 or control wildtype mice, with and without steatosis, were injected with syngeneic MC38 colon cancer cells. Examination of the two groups demonstrated a significant decrease in the number of tumors in the MMP13 null mice (P <0.01). Additionally, since the tumor cells themselves express MMP13, wildtype mice were injected with either shRNA control or MMP13 knockdown MC38 colon cancer cells to determine the role of tumor cell derived MMP13. Using transwell migration assay and the platypus invasion system with parental and MMP13 shRNA knockdown MC38 cells we found that loss of MMP13 decreases the invasive and migratory properties of the metastatic cancer cells in vitro. In conclusion, we found that MMP13 is elevated in the setting of steatosis and that loss of both stromal and tumor derived MMP13 lead to decreased number of metastatic foci in the liver. Tumor derived MMP13 effects tumor cell migration and invasion invitro. MMP13 may thus be a potential target to control initiation and growth of metastatic cancer of the liver.

Citation Format: Alisha Maria Mendonsa, Michael N. VanSaun, Lee Gorden. Contribution of MMP13 to tumor development in the steatotic liver microenvironment. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4984. doi:10.1158/1538-7445.AM2014-4984
Abstract 4989: Desmocollin 2 suppresses lung cancer cell migration and invasion through down-regulation of NDRG1 expression
Authors: Hsu Yu-Chih , Ou Po-Chun , Chen Yu-Yi , Tsai Meng-Feng
Published: May 2015

Desmocollin-2 (Dsc2), a calcium-dependent transmembrane glycoprotein, is the most widely distributed form of desmocollins that plays a critical role in the maintenance of normal tissue architecture in epithelia. Reduced expression of Dsc2 has been reported in colorectal carcinomas, suggesting that Dsc2 may play a role in the development and progression of colorectal cancer. Recently, down-regulated of Dsc2 expression was also found in breast, esophageal, and lung carcinomas. Dsc2 may act as tumor suppressor in various cancers. However, the role of the Dsc2 in lung cancer cells is still unclear. In this study, we report that knockdown Dsc2 expression using small-hairpin RNA (shRNA) approach can promote lung cancer cell migration and invasion abilities. Consistent with these findings, ectopic expression of Dsc2 inhibited cell migration and invasion in lung cancer cells. Additionally, we also suggested that Dsc2 inhibited lung cancer cells motility and epithelial to mesenchymal transition (EMT) through down-regulate NDRG1 and Slug expression.

Citation Format: Yu-Chih Hsu, Po-Chun Ou, Yu-Yi Chen, Meng-Feng Tsai. Desmocollin 2 suppresses lung cancer cell migration and invasion through down-regulation of NDRG1 expression. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4989. doi:10.1158/1538-7445.AM2014-4989