bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 1433: Tumor-associated fibroblasts increase HNSCC invasion in the presence of carcinogen NNK via activation of EGFR and c-Met
Authors: Kim Joseph , Panahandeh Mary , Thomas Sufi M.
Published: February 2011

Tobacco smoking is a major risk factor for head and neck squamous cell carcinoma (HNSCC); one of the leading causes of cancer mortality. Nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) a major product of cigarette smoke and is a well known carcinogen. Approximately 20 − 40% of former smokers continue to smoke 1 year post-HNSCC diagnosis. The role of NNK in tumor progression remains unknown. We hypothesize that exposure to carcinogens such as NNK contributes to the invasive and metastatic ability of HNSCC. In addition we believe it affects the surrounding stromal tissue, facilitating tumor progression. In order to examine the effects of NNK on HNSCC and stomal fibroblast invasion, we used Matrigel-coated transwell invasion chambers, where the cells were plated on top of the Matrigel for 24 h following which the invaded cells were fixed, stained, and counted. Our data demonstrate that NNK (10 nM) increases invasion in both HNSCC cells as well as surrounding stromal fibroblasts though Matrigel. Further, we demonstrate that NNK treatment resulted in activation of the epidermal growth factor receptor (EGFR) and c-met in HNSCC cells. EGFR activates downstream molecules increasing HNSCC invasion. Inhibition of EGFR using the EGFR specific antibody cetuximab abrogates NNK-induced invasion in HNSCC cells. Neutralizing antibodies to HGF abrogates NNK induces invasion in the presence of tumor associated stromal fibroblasts. These findings provide important insights into mechanism whereby NNK contributes to tumor progression. Further, inhibition of EGFR abrogates NNK-mediated invasion of HNSCC and may facilitate loco-regional spread of the disease.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1433.
Abstract 1436: Interleukin-17A stimulates expression of chemokines and cytokines in prostatic epithelial cells via nuclear factor-kappaB and extracellular signal-regulated kinase pathways
Authors: You Zongbing , Ge Dongxia , Liu Sen
Published: February 2011

T helper 17 (Th17) cells secret interleukin-17A (IL-17A) and interleukin-17F. Th17 cells and IL-17A are increased in prostate tumors. The role of IL-17A in prostate cancer is not clear. The objective of this in-vitro study was to investigate the effects of IL-17A on prostatic epithelial cells. Cell growth assay, Western blot, and real-time quantitative reverse transcription- polymerase chain reaction (qRT-PCR) analysis were used to measure the effects of IL-17A on the immortalized normal human prostatic epithelial cell lines (RWPE-1 and pRNS-1-1), human high-grade prostatic intraepithelial neoplasia (PIN) cell line, human prostate cancer LNCaP cell line, and mouse prostate cancer TRAMP-C1 cell line. We found that recombinant human IL-17A (20 ng/ml) did not affect cell growth rate in any of the prostatic cell lines studied. IL-17A did not significantly activate Nuclear Factor-kappaB (NF-kappaB) or Extracellular signal-Regulated Kinase (ERK) signaling pathway in RWPE-1, pRNS-1-1, or PIN cells. IL-17A activated NF-kappaB and/or ERK signaling pathways in LNCaP and TRAMP-C1 cells. When IL-17RC (receptor of IL-17A) was overexpressed in PIN and LNCaP cells, activation of NF-kappaB or ERK signaling pathway by IL-17A was significantly enhanced. IL-17A modestly induced mRNA expression of chemokines (CXCL1 and CXCL2) in RWPE-1, pRNS-1-1, and PIN cells. IL-17A induced mRNA expression of chemokines (CXCL1, CXCL2, CCL2, CCL5, CCL7, and CCL20) and cytokine IL-6 in LNCaP cells. In mouse TRAMP-C1 cells, IL-17A induced mRNA expression of chemokines (CXCL1, CXCL2, CXCL5, CCL2, and CCL5) and cytokine IL-6. When IL-17RC was overexpressed in PIN and LNCaP cells, chemokine expression was significantly enhanced. Our findings suggest that although IL-17A has no effects on cell growth in-vitro, it may modulate the stroma-epithelial interaction in tumor microenvironment in-vivo via stimulation of expression of chemokines and cytokines.

Acknowledgement: DoD W81XWH-05-1-0567, NIH/NCRR 2P20 RR020152-06, and LCRC Fund.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1436.
Abstract 1441: Use of RFP and GFP transgenic nude mice to study the tumor microenvironment of liver metastasis
Authors: Suetsugu Atsushi , Osawa Yosuke , Nagaki Mashito , Saji Shigetoyo , Moriwaki Hisataka , Momiyama Masashi , Bouvet Michael , Hoffman Robert M.
Published: February 2011

The tumor microenvironment (TME) is critical for tumor progression in the liver. To examine the role of the TME in liver metastasis, we developed color-coded imaging of the TME using green fluorescent protein (GFP) transgenic and red fluorescent protein (RFP) transgenic nude mice, to investigate cancer-host-cell interaction. Non-colored human colon cancer cells (HCT-116, 2×106 / 50 µl) were injected in the spleen of GFP or RFP nude mice. Fluorescence imaging of the metastatic liver tumors used the Olympus OV100 small animal imaging system. The fluorescence area of the liver was measured and liver sections were stained with hematoxylin and eosin and desmin. HCT-116 cells formed tumor colonies in the liver 28 days after cell transplantation to the spleen. In the metastatic liver tumors in RFP nude mice, RFP-expressing stroma cells derived from the host animal appeared around the edge of HCT-116 tumors. The infiltration of RFP-expressing inflammatory cells was observed in the central necrotic area of the tumors. The fluorescence of the metastatic liver tumors in the GFP nude mice was weaker than that from the RFP mice. In the GFP mouse, only non-parenchymal cells of the liver had GFP fluoresecence. The GFP non-parenchymal cells greatly increased in the liver during tumor-colony growth and surrounded the metastatic tumors. Desmin positive cells predmoninated in the non-parenchymal and increased around the metastatic tumors suggesting that fibroblasts are greatly increased around the metastatic tumors in the liver and may have a role in tumor progression. This novel imaging model of the TME will enable the identification and characterization of stromal cells involved in cancer progression in the liver.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1441.
Abstract 1446: Effect of PF-03475952, a potent and neutralizing CD44 antibody, on cancer cell apoptosis in vitro and metastasis in two orthotopic models
Authors: Wang Yuli , Wang Jean , Li Gary , Jackson-Fisher Amy , Brett Simmons , Kraynov Eugenia , Li Baiyong , Pocalyko David
Published: February 2011

Effect of PF-03475952, a potent and neutralizing CD44 antibody, on cancer cell apoptosis in vitro and metastasis in two orthotopic models

Yuli Wang, Jean wang, Gary Li, Amy Jackson-Fisher, Brett Simmons, Eugenia Kraynov, Christy Ji, Baiyong Li, and David Pocalyko

Pfizer Global Research & Development, San Diego, CA 92121

CD44 is a cell surface glycoprotein that has multiple functions. It can act as a receptor for ligands such as hyaluronic acid and osteopontin. Additionally, it can function as co-receptor to modulate the activation of growth factor receptors such as c-met & ERBB. CD44 can also influence cell signaling through interaction with components of the actin cytoskeleton such as the ERM protein.

CD44 expression is increased in many types of human cancer. It is also a cell surface marker for cancer stem cells in breast cancer and HCC. In HCC, CD44 overexpression is a frequent event (∼30% based on several reports) and CD44 up regulation is associated with metastasis and poor patient survival. Down regulation of CD44 with RNAi knockdown or neutralizing antibody has been reported to reduce tumor metastasis, recurrence, and growth in different models.

PF-03475952 is a fully human IgG2 anti-CD44 monoclonal antibody that was initially developed as a potential therapeutic agent for rheumatoid arthritis. It was shown previously that the PF-03475952 can disrupt the interaction of CD44 with its ligand, hyaluronic acid. The antibody binding induces loss of CD44 from the cell surface, and inhibits LPS-induced cytokine release from various leukocytes.

In this report, we evaluated the potential of PF-03475952 as a cancer adjuvant therapy for HCC. HCC is the third most deadly forms of cancer world-wide with frequent early recurrence due to inter and extra hepatic metastasis. The effect of PF-03475952 on cancer metastasis was first demonstrated in an M24met melanoma model. The expression of CD44 and the effects of PF-03475952 on HCC cell lines were then characterized. In vitro, PF-03475952 was able to reduce cell adhesion and promote apoptosis in a CD44-dependent manner. More importantly, PF-03475952 can reduce lung metastasis in a CD44-positive HCC orthotopic model.

The study suggested that the CD44 neutralizing antibody, PF-03475952, could be an efficacious agent as adjuvant therapy to prevent cancer metastasis.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1446.
Abstract 1452: Examination of mechanisms involved in spontaneous melanoma metastasis to CNS
Authors: Cruz William , Man Shan , Jaramillo Maria , O'Connor-McCourt Maureen , Banville Myriam , Kerbel Robert S.
Published: February 2011

Cerebral metastases occur in a majority of metastatic melanoma patients and are the major cause of mortality in those cases. Testing of novel therapeutic approaches has been slowed by the absence of appropriate preclinical models of spontaneous metastatic melanoma, particularly spontaneous CNS metastasis. To examine the efficacy of potentially promising treatment regimens, a highly visceral metastatic variant of the human melanoma WM239 cell line, named 6-4L, was developed and used to test the effectiveness of metronomic chemotherapy in the treatment of advanced metastatic disease. Concurrent low-dose cyclophosphomide/vinblastine led to significant disease control of mice with overt metastases in lungs, liver and lymph nodes. Among mice that survived the long-term treatment, 20% showed the presence of spontaneous brain metastases which likely emerged as a result of prolonged survival mediated by the therapy. From these, 2 cell lines (131/4-5B1 and 131/4-5B2) were generated which metastasize spontaneously to brain parenchyma. This constitutes the first model of heritable spontaneous melanoma brain metastasis by a human cell line from a subdermal transplant, without any therapeutic intervention. Characterization shows two salient functional alterations that may contribute to this phenotype 1) adhesion to brain-endothelial cells and 2) proliferation in the presence of brain-derived factors. When compared to poorly or highly metastatic cell lines (WM239A and 113/6-4L respectively), microarray analysis shows that 4-5B1/B2 cell lines have markedly different expression profiles. These cell lines show differential expression of 108 genes, thirteen of which share a common alteration for both brain-metastatic cell lines, including ednrb (endothelin receptor B) and bcl2a1 (BCL2-related protein A1), which stand out as potentially relevant. These molecules have been previously associated with increased proliferation in the presence of ENT-3; a peptide expressed in the brain, as well as resistance to TNF induced apoptosis and increased metastatic potential. Lentiviral vectors were used to induce stable upregulation of these genes in the otherwise non-brain metastatic parental 113/6-4L cell line. This upregulation mediated an increase in metastatic potential and, in the case of EDNRB, increased intracranial tumor growth. Future efforts will focus on characterizing the alterations in these cell lines, to confirm their clinical relevance and to test novel inhibitors for treating melanoma brain metastases.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1452.
Abstract 1456: Cerebrospinal fluid vascular endothelial growth factor in patients with brain metastases from breast cancer
Authors: Song Susan S. , Malchow Chris , Lok Edwin , Swanson Kenneth , Wong Eric T.
Published: February 2011

There is a rising incidence of brain metastases from breast cancer. Having an improved means of detecting and monitoring such brain metastases would be valuable. Using samples stored in our Cerebrospinal Fluid (CSF) Bank, we identified 176 samples from 71 patients with brain metastases from breast cancer. The CSF VEGF levels were measured using enzyme-linked immunosorbent assay and normalized to phosphate buffered saline. The highest CSF VEGF ratios from individual patients were correlated with patient survival. The median CSF VEGF ratio was 1.043, with a range of 0.575 to 22.060. At the time of analysis, 51 patients were deceased while 30 were alive, with a median survival of 4 months. The median survival of patients with CSF VEGF ratio ≤ 1.000 was 7 months (range 1 to 31 months) versus 2.5 months (range 0.5 to 60 months) for those with CSF VEGF > 1.000. Furthermore, increasing CSF VEGF levels also appear to correlate with increasing number of brain metastases detected on magnetic resonance imaging. We conclude that VEGF is a potential biomarker in the CSF for brain metastases from breast cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1456.
Abstract 1458: Orthotopic imageable peritoneal carcinomatosis GFP nude mouse model of human esophageal cancer
Authors: Gros Stephanie J. , Dohrmann Thorsten , Kaifi Jussuf T. , Bouvet Michael , Hoffman Robert M. , Izbicki Jakob R.
Published: February 2011

The aim of this study was to establish an imageable orthotopic GFP-expressing nude-mouse model of human esophageal cancer peritoneal carcinomatosis. Nude mice were orthotopically injected in the abdominal esophagus with stably transfected GFP- PT1590 human esophageal cancer cells. Tumor progression was visualized by fluorescence imaging. Fifty percent of the animals developed extensive peritoneal spread without a distinct primary tumor at the injection site. Continuous and metastatic spread to liver, lung, and lymph node was also observed. Fluorescence imaging enabled rapid and specific visualization of tumor progression without anaesthesia. Intraperitoneal and metastatic tumor spread of GFP-PT1590 esophageal carcinoma demonstrated a highly aggressive but heterogenous behaviour. Although injection of the esophageal carcinoma cell line PT1590-GFP did not lead to primary esophageal tumor development at the site of injection, 50% of the mice developed extensive peritoneal spread as well as lymph node and organ metastasis. The orthotopic cell injection model resulting in peritoneal carcinomatosis of esophageal adenocarcinoma, which can be visualized in real time using fluorescence imaging, will be a valuable tool for the study of esophageal cancer metastasis and its treatment.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1458.
Abstract 1471: Glycoprotein 90K suppresses Wnt signaling via ISGylation-dependent ubiquitination of β-catenin that needs interaction with CD9/CD82
Authors: Bae Jeong A , Lee Ji Hee , Sun Eun Gene , Bae Woo Kyun , Cho Sang Hee , Chung Ik Joo , Kim Kyung Keun
Published: February 2011

Backgrounds: Previously, we have observed that a tumor-associated 90K glycoprotein plays a potential tumor suppressor role in colorectal cancer (CRC) cells via antagonizing the canonical Wnt signaling pathway, which is functionally masked via interaction with extracellular galectin. Here, we investigated the signaling pathways of 90K action on CRC cells and its expression in human CRC tissues. Results: We identify a novel pathway comprising a secretory 90K and a CD9/CD82 tetraspanin web; in this pathway, 90K interacts with CD9/CD82, suppresses the Wnt/β-catenin signal via a novel proteasomal-ubiquitination mechanism of β-catenin that is dependent of ISG15 modification (ISGylation). In colon tissues from stage IV human CRC and invading cancer cells of corresponding metastatic liver tissues, in which β-catenin and galectin expression was higher, immunostained 90K and CD9/CD82 were lower than in adjacent hepatic tissues or colon tissues from stage I. Conclusions: 90K itself has antitumor activity in CRC cells via suppression of Wnt signaling with a novel mechanism of ISGylation-dependent ubiquitination of β-catenin when it interacts with CD9/CD82, but is downregulated in advanced CRC tissues. Our data suggest a strategy of strengthening this novel pathway with concomitant knockdown of galectins as a potential therapeutic approach to CRC progression.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1471.
Abstract 1472: Bcl-3 as a carcinogenic factor in non-endometrioid endometrial carcinoma
Authors: Lee Yoo-Kyung , Chung Hyun Hoon , Kim Jae Weon , Park Noh-Hyun , Kang Soon-Beom , Song Yong-Sang
Published: February 2011

Objectives : The aim of the study was to evaluate the Bcl-3 expression in normal endometrium, endometrial hyperplasia, and endometrial cancer.

Methods : Retrospectively collected paraffin blocks from 30 cases of normal endometrium, 16 of endometrial hyperplasia, 24 of endometrioid endometrial cancer, and 12 of non-endometrioid endometrial cancer were analyzed. Expression of Bcl-3 was assessed by immunohistochemistry. The staining pattern was correlated with clinicopathological variables.

Results : While none was positive in normal endometrium and endometrial hyperplasia and only 2 cases (8.3%) were positive for Bcl-3 in endometrioid endometrial cancer, 5 cases (41.7%) was positive in non-endometrioid endometrial cancer. Positive expression of Bcl-3 significantly correlated with non-endometrioid endometrial carcinoma (p=0.017), advanced stage (p=0.030), and high grade (p=0.001). Moreover, Bcl-3 positivity was associated with aggressive parameters including ovarian invasion (p=0.004), peritoneal cytology (p=0.029), lymphovascular space invasion (p=0.002), and lymph node metastases (p=0.029). In contrast, there was no significant correlation between expression of Bcl-3 and myometrial invasion or cervical invasion. In addition, Bcl-3 expression was not related to recurrence of disease.

Conclusion : Bcl-3 is strongly expressed in non-endometrioid endometrial cancer, but less frequently in endometrioid endometrial cancer and hyperplasia. It is suggested that Bcl-3 is related with the carcinogenesis of non-endometrioid endometrial cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1472.
Abstract 1478: Role of Stat3 Ser727 phosphorylation in mouse hepatocarcinogenesis
Authors: Ogawa Katsuhiro , Miyakoshi Masaaki , Yamamoto Masahiro , Tanaka Hiroki , Yaginuma Yuji
Published: February 2011

Inappropriate activation of signal transducer and activator of transcription 3 (Stat3) occurs with extreme frequency in a wide variety of cancers including HCC, and constitutive Stat3 activation in hepatocytes was demonstrated to accelerate hepatocarcinogenesis, while repression of Stat3 activation suppresses hepatocarcinogenesis. Diverse factors such as cytokines, growth factors and oncoproteins can activate Stat3, where phosphorylation of the conserved tyrosine residue at the C-terminus (Y705) results in the Stat3 homodimer or the heterodimer with Stat1, and phosphorylation of the serine residue on the transactivation domain (S727) contributes to its maximal transcriptional activity. The activated Stat dimers bind to specific DNA-response elements in the promoter of target genes and thereby induce unique gene expression programs cooperating with other transcription factors and cofactors. We investigated Stat3 activation in mouse hepatocarcinogenesis induced by neonatal treatment with diethylnitrosamine (DEN) and found that Stat3 phosphorylation occurred by two steps, where S727 phosphorylation was seen in the preneoplastic stage, whereas Y705 phosphorylation was further associated with malignant progression. In mouse HCC cells, serum treatment induced Ser727 phosphorylation via MAPK activation, associating with cell proliferation and Stat3 nuclear translocation, whereas IL-6 induced Tyr705 phosphorylation via JAK activation without stimulating cell proliferation and the Stat3 nuclear translation. On the other hand, the Ser727 phosphorylation dead Stat3 (S727A), in which the serine residue was replaced by alanine, reduced the cell proliferation and Stat3 nuclear translocation, while the Ser727-phosphorylation mimic Stat3 (S727D), in which the serine residue was replaced by aspartic acid, enhanced the cell proliferation and Stat3 nuclear translocation. To further investigate the role of Stat3 Ser727 phosphorylation, the Stat3 knockdown HCC cell lines were established by introducing the Stat3 siRNA into the mouse HCC cells. These cell lines showed retarded growth and less attachment to the substrate forming spheroidal aggregates, whereas the parent cells showed rapid proliferation and attached to the substrate with extended morphology. cDNA array analysis revealed that the Stat3 knockdown cells showed variety of gene expression changes relating to cell survival and growth, and RT-PCR demonstrated that the expression of EGFR, FGFR and E-cadherin was markedly reduced in the Stat3 knockdown cells. Our findings indicate that the Ser727-phosphorylated Stat3 plays an important role from the early stage in mouse hepatocarcinogenesis, presumably by controlling cellular growth and survival.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1478.
Abstract 1480: Characterization of C35, a novel protein binding partner of p73, in gynaecological cancers
Authors: Wong Sanna Ching-shan , Leung Thomas Ho-yin , Chan Karen Kar-loen , Ngan Hextan Yuen-sheung
Published: February 2011

The p53 family protein p73 encodes pro-apoptotic (TAp73) and anti-apoptotic (DNp73) isoforms. The functional role of the two isoforms in cancer development is still unclear. In this study, by yeast-2-hybrid screening using DNp73 as a bait, we identified C35 (C17orf37) as a novel protein interacting partner of p73. C35 was mapped to chromosome 17q12. It was overexpressed in breast cancer and prostate cancer. Its expression was positively correlated with the grade and stage of breast cancer progression. A recent study reported that C35 promotes cell migration and invasion in prostate cancer cells. However, the significance of C35 in cancer development remains to be elucidated. In this study, we focused on the functional role of C35 in gynaecological cancers. The binding of C35 and DNp73 was confirmed by co-immunoprecipitation. Quantitative real-time PCR revealed that mRNA expression of C35 in ovarian and cervical cancer cell lines was higher than that in normal cell lines. In addition, mRNA expression of C35 was significantly higher in ovarian cancer clinical samples than that in normal samples (p<0.0001, t-test). To investigate the function of C35, SiHa and OV2008 cells stably expressing C35 were established. The protein expression of C35 was confirmed by western blot analysis. In studying the effect of C35 on cell transforming ability, soft agar assay was performed. The result showed that the number of colonies formed by the C35 stable clones was significantly higher than those formed by the parental cells and control vector stably transfected cells. In addition, the size of the colonies formed by the C35 stable clones was larger. Wound healing assay and transwell migration assay were performed to investigate the effect of C35 on cell migration rate. We found that the migration rate of the C35 stable clones was higher than that of the parental cells and vector transfected cells. XTT assay revealed that the proliferation rate of the C35 stable clones was higher than that of the parental cells and vector controls. In summary, our findings suggested that C35 is overexpressed in ovarian cancer. C35 likely exerts its oncogenic roles to enhance transformation, cell migration and cell proliferation in gynaecological cancers. Further study of the significance of the DNp73-C35 interaction may give insight into their oncogenic properties.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1480.
Abstract 1481: Srx-Prx IV axis is required for human lung cancer cell maintenance, migration, and invasion
Authors: Wei Qiou , Jiang Hong , Xiao Zhen , Stephen Andrew , Baker Alyson , Young Matthew R. , Veenstra Timothy D. , Colburn Nancy H.
Published: February 2011

Sulfiredoxin (Srx) is a novel antioxidant protein that has been shown to reduce the hyper oxidized Peroxiredoxins (Prxs). Our previous study has demonstrated that Srx is required for tumor promoter induced cell transformation and is highly expressed in certain types of human skin cancers (Wei et al PNAS 2008). In this study, our goal is to further examine the expression of Srx in a broad range of human tumors and to explore its functional significance and molecular mechanisms in human cancer development. We found that Srx is highly expressed in several types of human lung cancers and its level is correlated with cancer malignancy and metastasis. Using human lung cancer A549 cell in culture, we found that knockdown of Srx significantly reduces anchorage independent growth in soft agar, cell migration in a wound-healing assay and cell invasiveness in a matrigel invasion assay. In an effort to discover downstream mediators of Srx-signaling pathway, we used affinity-based pull down and mass spectrometry methods to identify proteins that interact with Srx. To our surprise, Prx IV was found to be the most abundant protein that interacts with Srx in at least three different cell lines and the preferential interaction occurs independently of its expression levels. To characterize the Srx-Prx IV interaction, bacterial expressed recombinant Srx, Prx I, II, III and IV were individually purified. In an in vitro binding assay using Surface Plasmon Resonance technique, we confirmed that purified Srx has a much higher binding affinity to Prx IV than to Prx I, II or III. With a lentiviral based shRNA technology, each individual Prx was specifically knocked down in A549 cells. The phenotypic changes of these cells were compared to the Srx knockdown cells. We found that knockdown of Prx IV, but not other Prxs, was sufficient to recapitulate the attenuation of tumor phenotype and progression of Srx knockdown cells. In addition, we also confirmed that Prx IV undergoes rapid hyperoxidation in the presence of oxidative stress and is preferentially reduced by Srx in A549 cells. Overall our data indicate that Srx is highly expressed in human lung cancers and Srx-Prx IV axis is critical for human lung cancer cell maintenance, migration and invasion.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1481.
Abstract 1482: Autocrine IL-1α mediates NF-κB activation by oncogenic ras in keratinocytes
Authors: Cataisson Christophe , Salcedo Roselba , Hakim Shakeeb , Barrett Andrea , Lyakh Lyudmila , Trinchieri Giorgio , Yuspa Stuart H.
Published: February 2011

Inflammation is a complex process evolved to protect us against pathogens. There is increasing evidence that chronic inflammation can be a major cancer risk. Clinical and epidemiological evidence link inflammation with epithelial skin cancer. One of the best established models linking inflammation with the development of skin cancer is the classical two stage skin carcinogenesis in mice. MyD88 is a crucial intermediate in the signaling from pro-inflammatory receptors. Mice ablated for MyD88 or the IL-1R are resistant to topical skin carcinogenesis and MyD88 deficient ras -transduced keratinocytes form only small tumors in orthotopic grafts. In the skin model the clonal benign tumor defines the phenotype of the initiated cell. High proliferation, resistance to terminal differentiation and altered gene expression are hallmarks of that phenotype. Our previous studies have revealed that Ras activation is sufficient to produce this complete phenotype and fully initiate tumor formation. We recently reported that Ras induction of CXCR2 ligands was mediated by autocrine activation of EGFR and NF-κB and that activation of CXCR2 on ras transformed keratinocytes has both pro-migratory and pro-tumorigenic functions. In MyD88 deficient cells, transduction of ras activates the EGFR loop, but these keratinocytes do not upregulate CXCR2 ligands. Using both genetic and pharmacological approaches we have demonstrated that IL-1α autocrine signaling is activated downstream of EGFR in ras transformed keratinocytes. We further demonstrate that IL-1α is responsible for NF-κB mediated activation of CXCR2 ligands in those keratinocytes. Collectively, those results demonstrate that ras activation converts normal keratinocytes to a tumor phenotype through a series of feedback signals that provide therapeutic opportunities.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1482.
Abstract 1484: Aldose reductase inhibition prevents breast cancer cell growth and restores breast cancer cell hormone dependency
Authors: Reddy Aramati Bindu M. , Nair Hareesh B. , Ramana Kota V. , Ansari Naseem H. , Tekmal Rajeswar R. , Srivastava Satish K.
Published: February 2011

Breast Cancer (BC) is the second leading cause of cancer deaths in the U.S. women. Hormone ablation therapy reduces the risk of cancer recurrence and improves the survival rate of most BC patients. Although BC initially responds to estrogen ablation therapy, as the cancer progresses, the cancer cells become hormone-independent and prone to metastasis, a major cause of mortality in BC patients. The few currently available drugs that restore hormone dependence are only partially effective and prohibitively costly. Hence there is an urgent need for novel therapeutic modalities. We have recently shown that aldose reductase (AR)-catalyzed GSH-lipid aldehyde conjugates such as GS-DHN induces growth factors-, cytokines- and chemokines-mediated signals that activate PKC, PLC and PI3K, which regulate transcription of NF-κB- and AP1-dependent inflammatory markers. Further, AR has been shown to be overexpressed in human breast cancers. We have investigated the efficacy of AR inhibition in preventing BC cells growth and reversing hormone dependency of BC cells. Our results indicate that pharmacological inhibition of AR or siRNA ablation of AR prevents growth factor -induced proliferation of BC cells (MCF-7) in culture. Similar results were observed when MDA-MB-231 and MDA-MB-468 BC cells were used. To further investigate how AR inhibitor prevents BC cell growth, we have examined the role of AR in resensitization of BC cells to letrozole. We found that combination of fidarestat with letrozole was very effective in inducing maximum cell death in LTLT-Ca cells when compared to fidarestat alone. The combination treatment not only restored estrogen receptor-α (ER-α) levels but also down-regulated HER2/MAPK-signaling proteins. Further, AR-siRNA - transfected MCF-7/Aro and MCF-7 cells upregulated ER-α in western blot and ER-functionality assays whereas in LTLT-Ca cells, ER-α levels were down-regulated as in fidarestat treated cells. Targeting the LTLT-Ca cells with PLG-based fidarestat nanoparticles having polyethylene glycol (PEG)-5000 as stabilizer and conjugated with FITC significantly prevented the aromatase activity in BC cells. Thus we have identified a novel role of AR in BC cell growth and estrogen-dependence of hormone insensitive BC cells and suggest the use of AR inhibitors either alone or in combination with letrozole to prevent as well as treat BC.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1484.
Abstract 1495: Analysis of p53 mutations in human esophageal cancer
Authors: Jackson Jonathan M. , Elespuru Rosalie K.
Published: February 2011

Studies on p53 mutations occurring in human tumors have the potential to provide information on causes of human cancer. This is relevant for cancer risk assessment on new products. A database of p53 mutations in human tumors is maintained by Olivier and Hainaut at IARC. We analyzed esophageal squamous cell carcinoma (ESCC), a cancer with known geographic hot spots and life style associations. IARC search allows the rapid determination of sequence distribution, codon location, and strand bias of p53 mutations in tumors stratified by pathology, gender, and lifestyle factors such as tobacco and alcohol use. Although proportions of DNA sequence changes in tumors are provided in IARC profiles, the nature of sequence changes at each base pair is not. Of particular interest are the sequence changes at hot spots. We analyzed the DNA sequence changes among 1032 esophageal mutations occurring at hot spot codons 175, 248, 273, and 282. These are all CpG sites encoding arginine. However, the distribution of mutations was strikingly different at the different sites. At codon 175 (CGC) 98% of the mutations were CAC, virtually all showing strand bias, i.e. G to A from the G containing strand. At codon 248 (CGG), the mutation distribution was 49%TGG and 40% CAG, showing no strand bias, i.e. equally G to A or C to T. At codon 273 (CGT), the mutation distribution was 49% CAT, 33% TGT, and 12% CTT, demonstrating some strand bias but a broader distribution of sequence changes. At codon 282 (CGG), 92% were TGG, again showing striking strand bias. Codons 248 and 282 had identical target sequences but different distributions in the tumors, 282 showing strand bias and 248 showing equivalent distribution of mutations on both strands of DNA. A biased distribution of DNA sequence changes could be related to causal DNA lesions, asymmetric DNA repair, and/or selection of particular mutant phenotypes during tumor progression.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1495.
Abstract 1499: Gene therapy in a mouse model for malignant melanoma: Combining the activities of the p53/Arf and interferon pathways
Authors: Merkel Christian A. , Strauss Bryan E.
Published: February 2011

Background: Malignant melanoma cells typically maintain wild-type p53 in a non-functional state, due in part to the loss of ARF (p14ARF in humans, p19ARF in mice). Data have shown that interferon-β (IFNβ) can activate the transcription of p53 and interact with the ARF pathway as well. By using a p53-driven adenovirus, we sought to combine the action and regulation of p53, p19ARF and IFNβ for the treatment of malignant melanoma in an immunocompetent mouse model.

Methods: p53-responsive AdPG adenoviral vectors (Bajgelman and Strauss, 2008) containing p53, p19ARF and IFNβ were produced and expression verified by immunofluorescence and ELISA. In vitro evaluation of the antiproliferative effect of single or co-transduction of B16F10 cells (B16, p53 wild-type) was done by FACS after annexin/PI staining. C57/Bl6 mice were injected subcutaneously with B16 cells and tumors were allowed to develop (∼0.5 cm2). At this point, three consecutive intra-tumor injections (3 day interval between injections) of individual or combined adenoviral vectors were performed. Animals were then sacrificed and tumors collected and analyzed.

Results: The combination of IFNβ and p19ARF proved to be more effective in inhibiting proliferation of B16 cells than either treatment alone, both in vitro and in vivo. In vitro we observed that neither AdPGp19 nor AdPGIFNβ alone altered the cell cycle, though co-transduction with these vectors resulted in extensive cell death. Annexin-V staining was also increased by the combined, but not individual, treatments. Cell death was observed only after 90-120h of incubation, yet prior to this event, indicators of senescence (positive SA-βGal staining, loss of histone H3 acetylatation at Lys9) were revealed in both single and combined vector treatments. In vivo, we observed that the combined gene transfer strategy led to reduced tumor volume, reduced incorporation of BrdU and increased staining by TUNEL in the primary tumor. Assays are in progress to determine if the combined treatment is effective in reducing metastases and prolonging survival.

Conclusion: The use of p53-responsive vectors for the restoration of ARF expression in the presence of IFNβ represents a potential strategy for melanoma tumor suppression. While mechanistic studies are underway, we propose that the complementation of the p53/ARF and interferon pathways in the primary tumor may lead to reduction of metastases.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1499.
Abstract 1502: Adenoviral-mediated interferon α induces endoplasmic reticulum stress related cytotoxicity in human cancer but not normal cells
Authors: Zhang Xinqiao , Benedict William F.
Published: February 2011

We have previously shown that adenoviral-mediated interferon α (Ad-IFNα) treatment is specifically cytotoxic to various cancer cells, not only to the cancer cells sensitive to the interferon protein (IFNα), but also to the cells which are resistant to IFNα. We also found that there is very little cytotoxic effect of Ad-IFNα on non-cancer cells. The cancer cell specific toxic effects of Ad-IFNα can be classified into three different mechanisms: 1. Expression and secretion of interferon α protein that results in kill of IFNα sensitive cancer cells; 2. Direct kill of IFNα resistant cancer cells by Ad-IFNα and 3. Cancer cell kill by Ad-IFNα produced bystander factors.

After Ad-IFNα infection, the host cells produce a large amount of IFN protein. We hypothesized that this protein over-load is cytotoxic to cancer cells and may be a major reason for Ad-IFNα direct effect. We now report that Ad-IFNα infection induces ER stress and ER stress related apoptosis in human cancer but not normal urothelial cells. In addition we found that the Ad-IFNα produced bystander cytotoxicity was not related to ER stress.

To investigate whether Ad-IFNα induced cancer specific cytotoxicity was correlated with the activation of ER stress pathways, the expression of several markers of ER stress was studied. Experiments utilized the interferon resistant human bladder cancer cell line, KU7, and the normal human urothelial cell line, TERT-NHU, for the studies. We found that three ER stress response pathways examined were activated in KU7 cells. In contrast, the ER stress response pathways remained silent in the normal TERT-NHU cells or in KU7 cells treated with conditioned medium from Ad-IFNα treated KU7 cells (to test the effect of bystander factor produced cytotoxicity) the ER stress response pathways remained silent. After 24hr of Ad-IFNα exposure, KU7 cancer cells produced spliced X-box binding protein 1 (sXBP1), activating transcription factor 4 (ATF4) and activating transcription factor (ATF6) protein, and evoked an ER stress response that contribute to Ad-IFNα induced apoptosis in cancer cells. In addition, we found GADD153/CHOP and GADD34 were also upregulated following the activation of the three ER stress pathways, thereby signaling downstream effectors in a pro-apoptotic manner.

Ad-IFNα recently has been used in Phase I clinical trial for patient with superficial bladder cancer. The results presented here could provide a mechanistic basis for Ad-IFNα action and support the positive clinical results obtained to date.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1502.
Abstract 1507: Aberrant oncolytic human adenovirus late mRNA translation causes failure of viral progeny production in murine cancer
Authors: Young Anna M. , McNeish Iain A.
Published: February 2011

Introduction. Oncolytic viruses have therapeutic potential in cancer by selectively replicating within malignant cells, causing death. Adenovirus type 5(Ad5) mutant dl922-947 contains a 24 bp deletion in E1A-CR2 and selectively replicates in cells with an abnormal Rb pathway - a feature of 90% human malignancies. dl922-947 has activity in human ovarian cancer following intraperitoneal (ip) delivery. Immunocompetent models are essential to evaluate the host immunological response as adenoviruses induce robust immune responses and CD8+ T cell infiltration has prognostic importance in ovarian cancer. However, adenoviridae are species specific and Ad5 fails to produce infectious progeny in murine tissue, preventing development of such models. We have investigated why human adenovirus replication fails in murine cancer.

Methods. dl922-947 lifecycle was examined in murine carcinoma cells CMT64 and MOVCAR7 and human epithelial ovarian cancer (EOC) cells OVCAR4.

Results. Infectivity, qPCR and sub-fractionation assays demonstrated no deficit in virion internalisation, genome replication or mRNA nuclear export in murine cells. E1A transcription and expression were similar in murine and human cells. However, there was marked failure of late viral capsid protein expression on immunoblot, which was not reversed by proteasome inhibition. TCID50 assay confirmed minimal infectious progeny production in murine cells (0.005-0.25 pfu/cell at MOI 10 in murine cells vs 104 pfu/cell in OVCAR4 cells 48h pi). Temporal differences in late gene transcription were seen between OVCAR4 and MOVCAR7 but not CMT64 cells, whilst late mRNA processing was qualitatively normal in murine cells. dl922-947 infection failed to induce global shut-down of host protein translation in murine cells on Coomassie staining. Transcription of L4 100K, important for preferential viral mRNA translation, was 1 log lower in murine cells than human controls, which may contribute to decreased production of infectious virions. Interestingly, co-infection of MOVCAR7 cells with dl922-947 and murine adenovirus type 1 (MAV-1) partially rescued late viral protein expression and increased dl922-947 cytotoxicity by MTT assay (>50% reduction of EC50).

Conclusions: Failure of late viral mRNA translation results in failure of dl922-947 replication in murine cells. Current work focuses on the importance of the 5’ UTR tripartite leader sequence (TPL) common to all adenoviral late mRNAs. Specifically, sequence differences between human Ad5 and MAV-1 TPL may prevent adequate translation.

Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1507.
Abstract 1510: Improving replication kinetics by using a single shRNA p21/Waf-1 construct in backbone of prostate specific CRAd
Authors: Hoti Naser U. , Mustafa Sadaf , Chowdhury Wasim , Johnson Tamara , Lupold Shawn E. , Rodriguez Ronald
Published: February 2011

Conditionally replicating adenoviruses (CRAds) represent a promising modality for the treatment of neoplastic diseases, including Prostate Cancer. Selectively replicative viruses can be generated by placing a tissue or cancer-specific promoter upstream of one or more of the viral genes required for replication (e.g., E1A, E1B). We have previously reported the attenuated replication of these viruses by multiple cellular mechanisms. In this study we investigated the importance of p21/Waf-1, a cdk inhibitor on viral replication and tumor growth. Using RNA interference against p21/Waf-1 in prostate cancer cells we demonstrated an increase viral replication and viral oncolysis of the prostate cancer cells. Similarly CRAd viruses that carry p21/Waf-1 shRNA (Ad5-RV004.21) were able to prevent tumor outgrowth by inhibiting growth of established tumor xenografts that resulted in a marked increase in the mean survival time of tumor-bearing mice compared to CRAd with out p21/Waf-1shRNA (Ad5-RV004) or mock treated control groups. Furthermore in combinatory studies of Ad5-RV004.21 with Adriamycin a supra-additive effect was observed only in CRAds viruses that harbor shRNA against p21/Waf-1. Taken together these findings of enhance viral replication in prostate cancer cells by using RNA interference against the cdk inhibitor (p21/Waf-1) have significant implications in the development of prostate-specific CRAd therapies.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1510.