bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 2359: Regulation of cytoskeleton organization by sphingosine in a mouse cell model of ovarian cancer progression
Authors: Creekmore Amy L. , Schmelz Eva M. , Roberts P. C. 
Published: June 2012

Abstract
Ovarian cancer is the fifth leading cause of cancer deaths among women mainly because of late detection of the disease due the lack of symptoms and reliable biomarkers. Approximately 90% of ovarian cancers are derived from the surface epithelium of the ovary. To further investigate the events that lead to progression of epithelial ovarian cancer, we previously developed a cell model of ovarian cancer. Mouse ovarian surface epithelial (MOSE) cells that have undergone spontaneous transformation in cell culture were categorized into distinct morphological and phenotypical stages based on passage history: early passage cells (MOSE-E) represent a pre-neoplastic, non-tumorigenic phenotype whereas late passage cells (MOSE-L) exhibit a highly aggressive malignant phenotype both in vitro and in vivo. In depth studies of genetic changes during MOSE cell progression in our labs have identified the cytoskeleton and its regulatory genes as critical early progression events. These changes in gene expression led to an increasingly dysregulated cytoskeleton which may affect the intracellular localization of signaling intermediates, and, thereby, important downstream signaling events involved in cancer progression. Sphingosine (SO), a bioactive metabolite of complex sphingolipids, has been shown to have chemopreventive activity against cancer, including cancer of the colon, breast and ovarian. In the present study, we have investigated the hypothesis that SO prevents or reverses the observed aberrant cytoskeleton organization, and thereby affects the cells metastatic potential. In MOSE-L cells, SO treatment did not significantly influence the gene expression or protein levels of several cytoskeleton components or regulatory proteins. However, immunostaining of SO-treated MOSE-L cells revealed a reversal of the aberrant cytoskeleton organization and mislocalization of regulatory proteins, many of which are associated with cell migration. This corresponds to observations that SO reduces cell motility in MOSE cells. Our data indicates that cytoskeleton re-organization induced by exogenous SO treatment may be involved in the regulation of signaling pathways that reduce proliferation, migration and invasion of the MOSE cells.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2359. doi:10.1158/1538-7445.AM2011-2359
Abstract 236: DKK-3, a secreted Wnt antagonist, suppresses tumorigenic potential and lung metastasis of osteosarcoma
Authors: Guo Yi , Rubin Elyssa , Pourmorady Jonathan , Christ Alexander , Rooney Kevin , Eskander Ramez , Sakai Toshinori , Bhatia Nitin , Zi Xiaolin , Hoang Bang H 
Published: June 2012

Abstract
Osteosarcoma (OS) is the most common primary malignancy of bone. Current therapeutic protocols focus on intensive chemotherapy and radical surgical resection. However, 5-year survival rate remains low when patients present with pulmonary metastasis, suggesting a need for more effective targeted therapies. In this study, we examined the in vivo anti-tumor effects of Dickkopf-3 (Dkk-3), a secreted Wnt antagonist, in a mouse model of osteosarcoma. Osteosarcoma 143B cells over-expressing Dkk-3(143B/Dkk-3) was established by stable gene transfection. To examine the effects of Dkk-3 on tumorigenesis and lung metastasis of osteosarcoma, nude mice were injected subcutaneously or orthotopically in the proximal tibia with 143B/Dkk-3-transfected vs. control cells to establish local tumor and lung metastasis. Dkk-3 dramatically inhibited local tumor growth in engrafted mice. In the orthotopic intratibial injection model, 143B/Dkk-3 cells formed significantly fewer lung nodules than control cells. In order to determine the potential molecular mechanism underlying the anti-tumor effect of DKK3 on osteosarcoma, we examined the reversal of EMT (Epithelial Mesenchymal Transition) and the expression of c-Met and MMPs (Matrix metalloproteinase) by real time PCR and western blot. Dkk-3 significantly reversed the epithelial-mesenchymal transition of osteosarcoma cells by inducing expression of epithelial markers (E-cadherin, keratin 8, and keratin18) and repressing the expression of mesenchymal markers (N-cadherin, Vimentin, and fibronectin). Dkk-3 also inhibited the expression and proteolytic activity of metalloproteinases and down-regulated oncogenic c-Met expression. Our study suggested that Dkk-3 effectively inhibits both local tumor growth and lung metastasis by suppressing multiple oncogenic pathways. Therefore, over-expressing DKK3 may represent a novel therapeutic strategy for osteosarcoma patients.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 236. doi:10.1158/1538-7445.AM2011-236
Abstract 2367: RhoA GTPase but not cortactin is required for tumor cell migration of human epidermoid carcinoma cells in vivo
Authors: Robertson Amy E. , Leong Hon S. , Lewis John D. 
Published: June 2012

Abstract
Metastasis contributes to over 90% of cancer mortalities. Metastatic disease is a dynamic, multi-step process that requires invasion and migration of cancer cells from the primary tumour site and leads to colonization at a distant location. Migration events mediated by the family of Rho GTPases are facilitated by acto-myosin contraction at the cell rear. In vitro studies have demonstrated that knockdown of RhoA causes insufficient actomyosin contraction and decreased cell detachment. Migration of cancer cells in vivo does not only require detachment from the primary tumor, but also relies on invasion of the cell into the surrounding stromal tissue. Formation of functional invadopodia drives invasion and a key component of invadopodia is cortactin. The objective of this study is to combine inhibitory short hairpin RNA (shRNA) technology with an in vivo metastasis model to identify mechanisms of cancer cell migration that have not previously been studied in an animal model. I hypothesize that inhibition of mediators required for cellular rear detachment and invadopodia formation, such as RhoA and cortactin respectively, will prevent migration of human fibrosarcoma (HT1080) and human epidermoid carcinoma (Hep3) cell lines in vivo.
Inhibition of RhoA and cortactin was performed by lentiviral infection of Hep3 and HT1080 cell lines with individual pLOK.1-puro vectors containing a 21-mir sequence to target and decrease mRNA expression. The migratory ability of both cell lines following RNA inhibition was analyzed in vitro using a scratch wound assay and in vivo using a migration and metastasis model in the shell-less chicken embryo, whereby transduced HT1080 and Hep3 cells are injected intravenously and subsequently arrest in the chorioallantoic membrane (CAM). We used a microscope mounted incubator and spinning disc confocal microscopy to visualize cells in real time and quantify their migration parameters.
Results obtained from in vitro migration assays indicate that inhibition of cortactin does not affect the migration of Hep3 and HT1080 cell lines across a rigid substratum. Diminished levels of cortactin also had no significant effect on the migration of these cells in vivo. Importantly, inhibition of RhoA caused a significant decrease in cell migration in vitro for both cell lines and in vivo for Hep3 cells (p&lt;0.05). This data suggests that RhoA, a key mediator of cellular rear detachment, is required for in vivo migration of human epidermoid carcinoma cells while cortactin, implicated in invadopodia structures, is not required.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2367. doi:10.1158/1538-7445.AM2011-2367
Abstract 2369: Isolation of circulating tumor cells by size exclusion using lithography fabricated precision microfilters
Authors: Adams Daniel , Makarova Olga , Zhu Peixuan , Li Shuhong , Amstutz Platte , Tang Cha-Mei 
Published: June 2012

Abstract
Background: We present a novel precision microfilter that achieves rapid and highly efficient isolation of circulating tumor cells (CTCs) from peripheral blood. Isolation of CTCs by size exclusion is a widely researched technique with the advantage of capturing cells without reliance on cell surface expression markers. For many years CTC filtration technology has relied on track-etch microfilters with randomly located pores and low-porosity. More recently, precision microfilters with high porosity have been tested for CTC isolation, but they are not widely available. We have developed a new method of fabricating precision, high porosity microfilters that are capable of high volume manufacturing. These microfilters are strong, clear, non-fluorescent, and have high CTC capture efficiencies.
Methods: We describe an assay to capture and enumerate prefixed and live CTCs. MCF-7 human breast adenocarcinoma cells (ATCC) were cultured in DMEM until confluent. Cells were stained in a fixative/staining solution containing paraformaldehyde, acridine orange, and DAPI dilacetate. After incubation, a cell sample was placed on a microscope slide and cells counted to obtain the exact input. Cells were then washed into 7.5 mL whole human blood with 7.5 mL PBS and placed into a syringe. An 8 µm pore precision microfilter was placed into Swinnex filter holder, and the sample drawn by negative pressure through the filter at ∼10 mL/min. The microfilter was mounted onto a microscope slide and counted using a fluorescence microscope under FITC and DAPI settings. Cells were defined by their shape and coloration under FITC fluorescence and nuclear signature under DAPI fluorescence. The procedure was then repeated using a staining solution without fixative to capture live MCF-7 cells. Both live and fixed MCF-7 cell isolation by microfiltration were performed in triplicate.
Results: Precision microfilters were able to capture MCF-7 cells spiked into 7.5 mL human blood with a recovery rate of 98±3% for fixed cells, and 90±2% for live cells. The filtration was performed in 2 minutes, and cell counts were obtained in 10 minutes. By contrast, track-etched microfilters captured only 73% of fixed cells and cell counts required 20 minutes.
Conclusions: Creatv's precision microfilters are shown to recover MCF-7 cells more efficiently than track-etch filters. The pore uniformity and low fluorescent background allowed for faster and more accurate counts of spiked CTC in human peripheral blood compared to track-etch microfilters.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2369. doi:10.1158/1538-7445.AM2011-2369
Abstract 2382: A critical role of tumor-specific hedgehog signaling for pancreatic cancer metastasis
Authors: Sheng Tao , He Jing , Zhang Xiaoli , Rychahou Piotr , Yang Ling , Xie Guorui , Wang Huamin , Evers Nark , Xie Jingwu 
Published: June 2012

Abstract
The hedgehog (Hh) pathway plays a vital role in embryonic development and tissue differentiation, and aberrant activation of this pathway is found in a variety of human cancer, including pancreatic cancer. Despite the significance of Hh signaling for cancer development, it is not clear whether Hh signaling in the tumor compartment is required for tumor metastasis of pancreatic cancer. Here we show that elevated expression of hedgehog target genes is highly associated with poor outcomes of pancreatic cancer patients, but not always with elevated expression of hedgehog molecules (SHH and IHH) or the known downstream signaling molecules. Target genes of Hh signaling were expressed in the tumor as well as in the stroma. We found that elevated Hh target gene expression is associated with increased expression of snail1 or loss of E-cadherin, implying that Hh signaling may be associated with the pancreatic cancer metastasis potential. To investigate how Hh signaling may affect cancer metastasis, we established an orthotopic mouse model of pancreatic cancer. We showed in this model that Hh signaling is elevated in lymph node and liver metastasis. The role of Hh signaling for pancreatic cancer metastasis was demonstrated in an orthotopic mouse model of pancreatic cancer, which involves activated hedgehog signaling. We found that knocking down Gli2 expression in the cancer cells, which was associated with reduced Hh target gene expression, prevents tumor metastasis to liver. Based on these data, we conclude that tumor specific Hh signaling activation is required for pancreatic cancer metastasis.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2382. doi:10.1158/1538-7445.AM2011-2382
Abstract 2400: Tumor suppressor EAF2 cooperates with p53 in control of prostate tumorigenesis and vascularity
Authors: Pascal Laura E. , Ai Junkui , Graham Lara E. , Xu Jianhua , Rigatti Lora , Pilch Jan , Zhou Wang 
Published: June 2012

Abstract
Introduction: Inactivation of EAF2 has been shown previously to lead to tumorigenesis in multiple organs; however the mechanism of EAF2 tumor suppression remains unclear. Demonstrating functional interactions between p53 and EAF2 would link the newly discovered tumor suppressor EAF2 to the well-established p53 pathway, providing new insights into the mechanisms of p53 and EAF2 action. We previously have shown that EAF2 can co-localize and co-immunoprecipitate with p53 in transfected cells. In a TSP-1 promoter-driven luciferase reporter assay, p53 transfection suppressed the TSP-1 promoter activity and EAF2 co-transfection blocked the p53 suppression of TSP-1 promoter. However, EAF2 transfection alone had little or no effect on the TSP-1 promoter. In a murine model, EAF2 knockout caused TSP-1 down-regulation, supporting an in vivo role for EAF2 in regulation of TSP-1 expression.
Methods: Mouse knockout, transient transfection, co-localization, co-immunoprecipitation, and luciferase-based promoter assay were employed in this study.
Results: Ongoing animal studies show that loss of EAF2 and p53 displayed much more dramatic phenotypes than loss of EAF2 or p53 individually and resulted in more severe splenic extramedullary hematopoiesis, and further increased vessel density in the prostate and liver. Furthermore, double knockout of EAF2 and p53, but not knockout of EAF2 or p53 alone, resulted in prostate tumorigenesis.
Conclusion: The above observations together suggest that EAF2 and p53 cooperate in prostate tumorigenesis and increased vascularity.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2400. doi:10.1158/1538-7445.AM2011-2400
Abstract 2415: TGF-ß signaling inactivation inhibits the formation of hepatocellular carcinomas induced by loss of p53
Authors: Morris Shelli M. , Baek Ji Yeon , Koszarek Amanda , Kanngurn Samornmas , Knoblaugh Sue E. , Grady William M. 
Published: June 2012

Abstract
Background: Hepatocellular carcinoma (HCC) is one of the most deadly forms of cancer and results from the accumulation of mutated or altered tumor suppressor genes and/or oncogenes. The tumor suppressor and oncogenes commonly affected include growth factors, receptors and downstream signaling components. Inactivation of the TGF-ß signaling pathway and mutation of TP53, the gene for p53, are common in HCCs suggesting they may cooperate in HCC formation. Thus, we assessed whether inactivation of TGF-ß signaling, by deletion of the TGF-ß receptor type II, TGFBR2, affects the formation of HCCs arising secondary to loss of p53.
Aim: To determine if loss of TGFBR2 and p53 cooperate in vivo to affect HCC formation.
Methods and Results: Albumin-cre (Alb-Cre) transgenic mice were crossed with mice homozygous for floxed Tgfbr2 (Tgfbr2flx/flx) and/or floxed Trp53 (Trp53flx/flx) to generate mice lacking TGFBR2 and/or p53 in the liver. Deletion of Tgfbr2 alone did not induce liver tumors, while inactivation of both Tgfbr2 and Trp53 resulted in a subset of mice (19%) that developed liver tumors by 65 weeks of age. Surprisingly, deletion of p53 alone, in the context of intact TGF-ß receptors, resulted in an increased number of mice developing tumors (38%), as well as increased morbidity (42 weeks of age). Interestingly, in both genotypes, Alb-Cre;Trp53flx/flx;Tgfbr2flx/flx and Alb-Cre;Trp53flx/flx;Tgfbr2wt/wt, the mice develop both hepatocellular carcinomas (HCC) and cholangiocarcinomas (CC), suggesting these tumors originate from a common liver stem cell population. Quantitative RT-PCR analysis of tumor and non-tumor tissue demonstrated a subset of Alb-Cre;Trp53flx/flx;Tgfbr2wt/wt (p53 null) tumors express significantly increased levels of alpha-fetoprotein mRNA, a clinical marker for HCC. Additionally, tumors from the Alb-Cre;Trp53flx/flx;Tgfbr2wt/wt displayed increased TGFβ-1 protein levels as compared to tumors from Trp53 and Tgfbr2 null mice. Furthermore, increased phosphorylated ERK1/2 expression was also present in the tumors from the p53 null mice and correlated with a slight up-regulation in beta-catenin expression, another common molecular event observed in human HCC.
Conclusions: The Alb-Cre;Trp53flx/flx;Tgfbr2flx/flx mouse model recapitulates many molecular features of human HCC and demonstrates that TGF-ß signaling is oncogenic in the setting of loss of p53 in the liver.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2415. doi:10.1158/1538-7445.AM2011-2415
Abstract 2421: Extracellular DNA in pancreatic cancer metastasis
Authors: Wen Fushi , Shen Alex , Choi Andrew , Shi Jiaqi 
Published: June 2012

Abstract
Extracellular nucleic acids have received increasing attention for their potential application in the rapid, accurate, and non-invasive early detection of cancer and other diseases, but less attention is given to their potential roles in cancer biology. We initiated a study to examine the role of extracellular DNA in pancreatic cancer metastasis. Pancreatic cancer is one of the most lethal cancers with a prognosis of just six months to live, and a five-year survival rate less than 5%. This is mainly due to the fact that at the time of diagnosis, 80-90% of patients have metastatic cancer already. To better understand the metastasis mechanism of this cancer, we tested the hypothesis that pancreatic cancer cells produce extracellular DNA to promote their metastasis and cancer cell adhesion to a new micro-environment.
We first examined the presence of extracellular DNA associated with pancreatic cancer cells by DAPI and CYTOX Green stains and by immunofluorescence assay (IFA) with the DNA-specific antibody. A large amount of extracellular DNA was observed on the surfaces and in the vicinity of the MiaPaCa-2 and BxPC3 pancreatic cancer cells but not the normal pancreas HPDE cells cultured on coverslips and in the 3D matrigel. A similarly larger amount of cell-free DNA was also found associated with the cancer cell line when the DNA from the cell culture media was extracted and analyzed. We subsequently stained tissue slides from human pancreatic cancer tissues, normal pancreas tissues, and the pancreatic cancer tissue microarrays using DNA-specific dyes and DNA -specific antibody in IHC and IFA. These experiments further confirmed the presence of extracellular DNA associated with the pancreatic cancer cells.
To understand the role of extracellular DNA in cancer metastasis, we studied the effect of treatment with DNase I on cell migration, invasion, proliferation, and colonization in vitro. We measured cell adhesion to plates coated with adhesion proteins. We also investigated de-attachment of cells from coverslips by proteinase K in the presence or absence of DNase I. These functional studies showed DNase I inhibited cell migration, invasion, and adhesion without affecting cell viability. In the 3D matrigel, DNase I completely changed the pancreatic cancer cell growth pattern.
We conclude that extracellular DNA associated with cancer cells play a novel role in cell migration, invasion, and cell adhesion in vitro. To our knowledge, this is the first report on the presence of a large amount of extracellular DNA on the surface and in the surrounding of pancreatic cancer cells and on the potential novel role of extracellular DNA in pancreatic cancer metastasis.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2421. doi:10.1158/1538-7445.AM2011-2421
Abstract 2423: B7-H3 contributes to increased metastatic potential of melanoma cells by interfering with the expression of metastasis-related genes
Authors: Nygren Marit K. , Tekle Christina , Chen Yih-Wen , Kristian Alexandr , Nesland Jahn Marthin , Mælandsmo Gunhild Mari , Fodstad Øystein 
Published: June 2012

Abstract
Metastatic malignant melanoma is a disease with a long time survival rate of only 5%. Since there is no effective treatment for advanced melanoma, detection of molecular markers involved in tumor progression and drug resistance can hopefully provide new insight in therapeutically aspects of this disease. We have been studying B7-H3 – a glycosylated transmembrane protein which has been shown to play a role in cancer progression through its immunoregulatory properties.
B7-H3 is highly expressed in melanoma cell lines as well as in clinical melanoma specimens, and we have previously demonstrated a role of the protein in chemoresistance. Thus, in this study, we wanted to investigate the possible function of B7-H3 in melanoma metastasis development.
We found that short hairpin RNA silencing of B7-H3 reduced the migratory potential as well as the matrigel-invasiveness of the malignant melanoma cells in vitro. In an in vivo experimental metastasis model, silencing of B7-H3 increased the symptom-free survival of nude mice and rats significantly, this in parallel with a lower fraction mice having microscopically detectable metastasis compared to control mice. The brain was the predominant organ with metastases and a clear difference between the nude mice injected with B7-H3 expressing cells and B7-H3 knock down cells was observed, with 10/14 and 6/17 mice having brain tumors, respectively. Furthermore, we found the expression of several metastasis-associated proteins, such as MMP-2, TIMP1 and TIMP2 to be regulated by B7-H3. In addition, the secretion of IL-8 was markedly reduced in the B7-H3 knock down cells as well as the phosphorylation of Stat3. Interestingly, activated Stat3 is known to play a role in brain metastasis.
Taken together, our findings suggest that B7-H3 might be a potential therapeutic target for anti-metastasis therapy in human melanoma.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2423. doi:10.1158/1538-7445.AM2011-2423