bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 4674: Associations between epidermal growth factor receptor polymorphism and survival in colorectal cancer patients treated with 5-FU based adjuvant chemotherapy
Authors: Lai Ching-Yu , Sung Fung-Chang , Hsieh Ling-Ling , Tang Reiping , Yeh Chih-Ching
Published: June 2012

Introduction: Colorectal cancer (CRC) is the second most common cancer and the third leading cause of cancer deaths in Taiwan. 5-Fluorouracil (5-FU) is one of the first line anti-cancer drugs used in the chemotherapy for CRC in older to raise survival rate. Epidermal growth factor receptor (EGFR) plays an important role to regulate gene expression causing cellular proliferation and apoptosis may induce malignant tumors. This retrospective study examined the association between EGFR polymorphism and overall survival of CRC patients treated with 5-FU-based chemotherapy.

Methods: A total of 499 patients diagnosed with CRC and received 5-FU-based chemotherapy after surgery between 1995 January and 2001 December was included in the present study. We genotyped the EGFR R497K (Arg 497 Lys) polymorphism using the polymerase chain reaction combined with the restriction fragment length polymorphism analysis (PCR-RFLP). Survival analyses on EGFR polymorphism were displayed with Kaplan-Meier curves and performed with log-rank test. The association between EGFR genotypes and survival was analyzed using Cox proportional hazard models.

Result: After 13 years follow-up, the median survival year was 4.56. The distribution of EGFR genotype was not significantly different by patients’ clinicopathologic characteristics. No significant EGFR genetic effects on overall survival were found in the present study, even the adjustment for age, gender, or tumor stage in the Cox proportional hazard models. However, in stage IV CRC patients, compared to the EGFR Arg/Arg genotype, the EGFR Arg/Lys and Lys/Lys genotypes were related to better overall survival with hazard ratio (HR) of 0.75 (95% CI = 0.49 – 1.15) and 0.61 (95% CI = 0.38 – 0.98), respectively. The Kaplan-Meier curves also showed that stage IV CRC patients carrying the EGFR Lys allele had a better survival (log-rank p = 0.07).

Conclusion: Our findings suggest that the EGFR R497K polymorphism may modify drugs activity to serve a prognostic predictor for stage IV CRC patients who receive 5-FU-based chemotherapy.

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 4674. doi:10.1158/1538-7445.AM2011-4674
Abstract 4680: Exploring the relationships between genetic variants within the UGT1A locus, cellular detoxification and risk of bladder cancer
Authors: Tang Wei , Fu Yi-Ping , Liu Luyang , Orduz Natalia , Kaushiva Alpana , Mumy Adam , Porter-Gill Patricia , Meyers Timothy , Garcia-Closas Montserrat , Malats Nuria , Chanock Stephen , Real Francisco X. , Kogevinas Manolis , Rothman Nathaniel , Silverman Debra , Prokunina-Olsson Ludmila
Published: June 2012

A recent genome-wide association study (GWAS) for urinary bladder cancer (UBC) has identified multiple novel genetic risk factors (Rothman et. al, Nat Gen, 2010). One of these factors was an intronic SNP rs11892031 (p=1.0×10-7) located within the UGT1A locus on chromosome 2q37. The human cellular detoxification uridine 5’ diphosphate (UDP)-glucuronosyltransferases (UGTs) belong to a superfamily of proteins that conjugate diverse endo and exotoxins, increase their solubility and facilitate their removal via bile and urine. The UGT1A locus includes nine protein-coding genes and four pseudogenes. Each first exon of these genes is regulated by its own promoter and is spliced to four constant exons producing nine UGT1A proteins.

Due to the complexity of the region and ∼90-95% similarity between the substrate-binding exon 1 sequences of UGT1A genes, this region is poorly represented in public databases (HapMap, 1000 Genomes, dbSNP). To ensure specificity of detection, we generated long-range amplicons and sequenced all UGT1A exons in HapMap individuals (CEU) and in 44 bladder cancer patients and identified 25 non-synonymous coding variations. All these variations have been genotyped in 1000 bladder cancer cases and 1000 controls from the Spanish Bladder Cancer Study (SBCS). We found one exonic SNP that showed association stronger than the original GWAS variant, and multiple variants that showed some evidence of gene and cigarette smoking interactions. Having ∼20 coding and potentially functional variants within the UGT1A region, we are exploring methods of simultaneous analysis of individual variants and their haplotypes. In conclusion, association of genetic variants within the UGT1A region confirms that altered cellular detoxification of environmental substrates is an important factor for development of bladder cancer.

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 4680. doi:10.1158/1538-7445.AM2011-4680
Abstract 4686: Requirements of Gαi1 and Gαi3 for brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) induced PI3K/AKT and MAPK signaling as well as neuronal survival and migration
Authors: Cao Cong , Toorie Anika , Latorraca Emily , Zhitkovich Anatoly , Marshall John
Published: June 2012

After the discovery of the involvement of neurotrophin receptor Trk (tropomyosin receptor kinase) in the biology of cancer, it is appreciated that inhibition of Trk activity is beneficial in the clinical oncology setting. The key intracellular mediators of activated Trk's pro-survival and pro-metastatic signals are PI3K/AKT and MAPK (mitogen-activated protein kinases) signaling, which makes it extremely important to dissect the molecular mechanism and signaling components involved in Trk regulation of those signaling. Here we focus on the two inhibitory alpha subunits of heterotrimeric guanine nucleotide-binding proteins, Gαi1 and Gαi3, in Trk signaling. Gαi proteins are couple to cell surface receptors to convey extracellular messages to their effectors. Our previous study has indicated an unexpected and critical role of Gαi proteins in mediating receptor tyrosine kinase signaling (Cao et al., Science Signaling, 2009). Here we discovered a novel function of Gαi proteins in BDNF/NGF signaling. Gαi proteins are required for Brain-Derived Neurotrophic Factor (BDNF) and Nerve Growth Factor (NGF) to transduce signals from Trk receptor to stimulate MAPK (p38, JNK and ERK) and PI3K/AKT/mTORC1 signaling. Knockout of Gαi1 and Gαi3 completely blocked BDNF and NGF induced PI3K/AKT/mTORC1 and MAPK activation in MEFs (mouse embryonic fibroblasts). Both Gαi1 and Gαi3 associated with the Grb2-associated binding protein 1 (Gab1), and were required for the interaction of Gab1 with SHP2 as well as the interactions of Grb2 with SHP2, Shc, MEKK1 and MEKK2, in response to BDNF and NGF. Loss of Gαi1 and Gαi3 impaired the phosphorylation of Gab1, SHP2 and Shc in response to BDNF and NGF. Importantly, siRNA knockdown of both Gαi1 and Gαi3 inhibited BDNF and NGF induced AKT/mTORC1 and MAPK activation in cerebellar granule neuron, and BDNF induced neuronal survival, neuronal migration and neurite outgrowth were also largely impaired in cerebellar neurons with Gαi1 and Gαi3 deficiency. Notably, in mice brain tissues (both cortex and cerebellum); double knockout of Gαi1 and Gαi3 also totally abolished BDNF induced signaling. Overall, these results showed that Gαi1 and Gαi3 lie downstream of Trk receptor, but upstream of Gab1-Shc-Grb2-Shp2, mediating MAPK and PI3K/AKT/mTORC1 signaling as well neuronal survival and migration. We discovered for the first time that Gαi1 and Gαi3 proteins are novel players in Trk signaling, we support that therapeutic options can be developed by targeting these two new players as novel anti-tumor strategy.

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 4686. doi:10.1158/1538-7445.AM2011-4686
Abstract 469: Mast cell inhibition by the BTK inhibitor PCI-32765 as a potential therapy in pancreatic cancer
Authors: Soucek Laura , Buggy Joseph , Kortlever Roderik , Swigart Lamorna Brown , Evan Gerard I.
Published: June 2012

A strong association between inflammation and cancer has long been recognized but the cause and effect relationship linking the two remains unclear. We previously showed that Myc, a pleiotropic transcription factor that is over-expressed in many human cancers, when expressed in a

β cell tumor model, triggers rapid recruitment of mast cells to the tumor site, a recruitment that is absolutely required for macroscopic tumor expansion. Indeed, such tumors did not grow in mast cell deficient mice. Furthermore, treatment of established

β cell tumors with cromolyn, a stabilizer that prevents mast cell degranulation, rapidly triggered hypoxia and cell death of tumor and endothelial cells. Our results suggested that inhibitors of mast cell function may prove therapeutically useful in restraining expansion and promoting regression of insulinomas and possibly other pancreatic cancers. However, such compounds have not yet been developed for systemic administration and applications in cancer therapy. In fact, there are no clinically effective systemic mast-cell blockers. Therefore, we tested PCI-32765 (Pharmacyclics, Inc.), a Bruton tyrosine kinase (BTK) inhibitor in clinical trials for treatment of B cell non-Hodgkin lymphoma, for its ability to inhibit mast cell function and tumorigenesis in our mouse model of β cell neoplasia and in a well characterized LSLKRasG12D model of pancreatic adenocarcinoma (PDAC). Here we compare and contrast the effects of long term treatment with PCI-32765 on mast cell degranulation, tumor growth and vasculature in both mouse models, establishing for the first time the therapeutic potential of mast cell inhibition by PCI-32765 in the treatment of insulinomas and other pancreatic cancers.

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 469. doi:10.1158/1538-7445.AM2011-469
Abstract 4690: Inhibition of PI3K-AKT signaling causes a FOXO-dependent induction of receptor tyrosine kinase expression and phosphorylation in cancer
Authors: Chandarlapaty Sarat , Sawai Ayana , Rodrik-Outmezguine Vanessa , Scaltriti Maurizio , Serra Violeta , Baselga Jose , Rosen Neal
Published: June 2012

Hyperactivation of the PI3K-AKT-mTOR pathway is a common mechanism for oncogenic signaling in tumors and multiple inhibitors of this pathway are now in clinical development. As the PI3K-AKT-mTOR pathway is known to be tightly regulated by negative feedback, we hypothesized that these drugs might relieve feedback inhibition, reactivate upstream signaling and limit their antitumor effects. We tested the effects of inhibitors of PI3K and AKT kinase on receptor tyrosine kinase signaling in a panel of cell lines derived from multiple tumor types. PI3K-AKT pathway inhibition resulted in increased expression and phosphorylation of a common set of receptor tyrosine kinases, including IGF-1R and insulin receptor and HER3. Induction of RTK expression was dependent on activation of members of the Forkhead transcription factor family in response to AKT inhibition. We found that depletion of FOXO proteins blocked the rise in HER3, IGF-1R, and insulin receptor protein and phosphorylation caused by AKT inhibition. Expression of a constitutively activated form of one of the FOXO proteins resulted in increased expression of these receptors. Moreover, immunoprecipitation of FOXO proteins revealed that they are preferentially associated with the promoters of these receptors upon AKT inhibition. To determine the consequences of induction of these RTKs, we utilized HER kinase inhibitors to block activation of the receptors. In multiple xenograft tumor models, PI3K-AKT inhibition resulted in potent RTK induction in vivo and combined inhibition of the HER kinases and AKT resulted in improved antitumor effects with tumor regressions observed in several cases. We conclude that the PI3K-AKT pathway feedback regulates RTK expression through a FOXO-dependent induction of RTK transcripts. This reactivation of upstream RTK signaling is likely to attenuate the effects of AKT inhibition. Blockade of feedback-upregulated RTKs may significantly improve the antitumor effects of PI3K-AKT inhibitors and is a potential combination strategy for PI3K-AKT driven cancers.

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 4690. doi:10.1158/1538-7445.AM2011-4690
Abstract 4701: Integrated chemo-genomics approach for the identification of therapeutically amenable targets in small cell lung cancer
Authors: Sos Martin L. , Heynck Steffi , Peifer Martin , Thomas Roman K.
Published: June 2012

Small-cell lung cancer (SCLC) is the third most common lung cancer type and with a median overall survival of only 9.3 month for extended disease patients also one of the deadliest worldwide. While analyses of the genetic landscape of non-small cell lung cancers led to the identification of therapeutically amenable targets such as mutant EGFR or EML4-ALK fusions, the characterization of oncogenic pathways that drive tumorigenesis in SCLC lags behind this development, resulting in a lack of treatment options for SCLC patients. To address this therapeutic need systematically we performed high-resolution gene-copy number (6.0 SNP-arrays) in a cohort of 108 SCLC specimens (n=47 primary samples; n=61 cell lines). This analysis revealed novel recurrent amplifications and deletions that are specifically enriched in SCLC when compared to non-small cell lung cancer specimen. We next annotated the significant genetic lesions found in our SCLC set and linked these with the activity profiles of a library of 270 novel proprietary compounds as well as compounds currently in clinical develop, which were screened in 51 SCLC cell lines. Using an integrated genomics approach we detected genetic predictors for the activity and resistance to known PI3K/AKT-pathway inhibitors as well as novel inhibitors previously not associated with activity in SCLC. Using orthogonal functional assays we validated genetic alterations that predicted cytotoxicity of Pi3-kinase inhibition in SCLC cell lines and we validated compounds that exhibited exquisite cytotoxicity in MYC-amplified tumors. Overall, our data provides the first detailed genetic landscape of small-cell lung cancer with a functional annotation and implies that PI3K/AKT-pathway inhibitors represent therapeutics that warrant further clinical investigation in SCLC 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 4701. doi:10.1158/1538-7445.AM2011-4701
Abstract 4705: MicroRNA-122 regulates liver metabolism and hepatocyte differentiation
Authors: Tsou Ann-Ping , Tsai Wei-Chih , Hsu Sheng-Da , Hsu Chu-Sui , Hsiao Ming-Shi , Chen Shu-Jen , Hsiao Michael , Huang Hsien-Da
Published: June 2012

MicroRNAs (miRNAs), inhibitors of gene expression, participate in diverse biological functions and in carcinogenesis. MicroRNA-122, a liver-specific miRNA, is known to regulate lipid metabolism and tumorgenesis and is down-regulated in the intrahepatic metastastic HCC. To obtain insights into the physiological function of miR-122, we successfully generated the mir-122-/- mutant mouse (122KO).

122KO mice are viable with reduced serum cholesterol, elevated alkaline phosphatase and portal infiltration. Collagen deposition suggested minor fibrosis in 122KO livers. 122KO mice have distinctly different lipid metabolism. The levels of cholesterol and triglyceride are low in serum but high in liver tissue. Lipoprotein analysis revealed that 122KO mice have defect in VLDL transport. These results indicate that mir-122 deletion generated pathological features reminiscent that of nonalcoholic fatty liver disease (NAFLD) in human. In addition, mir-122 deletion is also prone to hepatocarcinogenesis. Liver tumors developed at age of 11 months in 5/5 mice.

Expression of many genes was affected by mir-122 deletion. Pronounced changes are found in genes contributing to inflammation, cholestasis, fetal antigens, loss-of-imprinting and most importantly, expression of genes for metabolism of lipid and carbonhydrate are downregulated. The drastic change of transcriptome likely contributes to the pathological features presented in mir-122 knockout mice. We believe that 122KO mouse is a potential model for human HCC. This mouse model will provide a great opportunity to evaluate the physiological functions of mir-122 in hepatocyte differentiation.

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 4705. doi:10.1158/1538-7445.AM2011-4705
Abstract 4723: Soluble L1-CAM in the ascites is a prognostic marker in ovarian cancer
Authors: Bondong Sandra , Hielscher Thomas , Zeimet Alain , Zeillinger Robert , Cadron Isabelle , Sehouli Jalid , Vergote Ignace , Mahner Sven , Speiser Paul , Braicu Ioana , Huszar Monica , Fogel Mina , Altevogt Peter
Published: June 2012

L1-cell adhesion molecule (L1-CAM) is a 200-220 kDa transmembrane protein that belongs to the immunoglobulin superfamily. It was initially found to be expressed on neuronal cells and is involved in axon outgrowth and guidance during central nervous system development. L1-CAM overexpression has been reported for various tumor entities, where it correlates with advanced stage disease, metastasis and chemoresistance. In mouse models, L1-CAM promotes tumor growth and facilitates experimental tumor metastasis. The extracellular part of the full length L1-CAM is subject to membrane proximal cleavage, which generates a soluble form of about 200kDa (sL1-CAM). L1-CAM cleavage and release of the soluble molecule has been shown to promote migration, adhesion and protection from apoptosis of ovarian cancer cells in vitro. The soluble L1-CAM can be detected in body fluids like saliva, serum or ascites.

In a multi-centric retrospective study with 270 ovarian cancer patients, we analysed tumor samples to quantify membrane bound full length L1-CAM as well as ascites for sL1-CAM to study the value of L1-CAM as a prognostic marker. We found that L1-CAM expression on the tumor correlated with sL1-CAM in the ascites (rho=0.41). Increased L1-CAM levels on the tumor and in the ascites correlated significantly with a reduced overall survival (univariate p=0.028; 0.022). Elevated ascitic L1-CAM levels were also associated with poor progression free survival (p<0.0001) and remained an independent prognostic marker in multivariate analysis (p=0.0003). Furthermore, increased L1-CAM levels in the ascites correlated with an increased ascites volume (p=0.003). Patients with elevated L1-CAM levels in the tumor were at high risk for incomplete primary debulking (univariate p=0.01, multivariate p=0.04) and had an increased risk for lymph node metastases (p=0.004).

Given the in vitro role of L1-CAM in metastasis and invasion in addition to the findings of our study, we conclude that L1-CAM high expressing tumors show a more invasive phenotype which translates into a higher rate of incomplete debulking during upfront surgery. High levels of sL1-CAM in the ascites could serve as a reliable marker for prediction of early relapse and residual tumor burden in women suffering from ovarian cancer.

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 4723. doi:10.1158/1538-7445.AM2011-4723
Abstract 4740: Agonist anti-CD137 mAb act on tumor endothelial cells to enhance recruitment ofactivated T lymphocytes
Authors: Palazon Asis , Teijeira Alvaro , Martínez-Forero Iván , Hervás-Stubbs Sandra , Roncal Carmen , Dubrot Juan , Morales-Kastresana Aizea , Rouzaut Ana , Jure-Kunkel Maria , Melero Ignacio
Published: June 2012

Agonist monoclonal antibodies to the immune co-stimulatory molecule CD137, also known as 4-1BB, are presently in clinical trials for cancer treatment based on their co-stimulatory effects on primed T cells and perhaps other cells of the immune system. Here we provide evidence that CD137 is selectively expressed on the surface of tumor endothelial cells. Hypoxia upregulated CD137 on murine endothelial cells. Treatment of tumor-bearing immunocompromised Rag-/- mice with agonist

CD137 mAb did not elicit any measurable anti-angiogenic effects. In contrast, agonist mAb stimulated tumor endothelial cells, increasing cell surface expression of the adhesion molecules ICAM-1, VCAM-1 and E-selectin. When adoptively transferred into mice, activated T lymphocytes derived from CD137-deficient animals entered more avidly into tumor tissue after treatment with agonist mAb. This effect could be neutralized with anti-ICAM-1 and anti-VCAM-1 blocking antibodies. Thus, stimulation of CD137 not only enhanced T cell activation but also augmented their trafficking into malignant tissue, through direct actions on the blood vessels that irrigate the tumor. Our findings identify an additional mechanism of action that can explain the immunotherapeutic effects of agonist CD137 antibodies.

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 4740. doi:10.1158/1538-7445.AM2011-4740
Abstract 4750: Real-time imaging of 3-dimensional cancer cell movement in tissues
Authors: Digman Michelle , Aguilar Jose A. , Gratton Enrico , Suetsugu Atsushi , Hoffman Robert M.
Published: June 2012

Our knowledge of how cells move in 3D in tissues is limited due to the lack of imaging methods that can produce 3D images fast enough and with sufficient resolution. Cancer cells migrate in 3D by forming adhesion points at the end of very long cellular protrusions. These protrusions are very thin and it is difficult to visualize adhesions along the protrusion surface. Conventional 3D stack reconstruction has relatively low resolution unless it is done using many frames. This results in a very slow acquisition in 3D confocal microscopy. Faster methods of 3D data acquisition (spinning disk microscopy) cannot be easily implemented since there is significant amount of scatter in tissues. A major obstacle in imaging adhesions is to find and track them so that they will not go out of focus. We are developing a new method which is based on orbiting imaging around cellular protrusions to visualize protein dynamics during extravasation. A feedback mechanism controls the center of the orbit to be at the center of the fluorescence distribution. A program reconstructs the shape of the protrusions in 3D. The fluorescence intensity in one or more channels is also simultaneously measured. The fluorescence intensity of one channel is used to paint the protrusion shape, which results in the 3D reconstruction of the protrusion. During the orbit, the second channel of the microscope measures the second harmonic generation (SHG) signal. We then correlated the appearance of bright fluorescence spots on the protrusion surface with the points of contact of the protrusion. This method will enable imaging of cancer cell invasion in 3-dimentions in live mice in real time.

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 4750. doi:10.1158/1538-7445.AM2011-4750
Abstract 476: Defining two populations of prostate cancer cells with distinct molecular, biological, and tumor-propagating properties
Authors: Qin Jichao , Liu Xin , Laffin Brian , Chen Xin , Choy Grace , Jeter Collene , Calhoun-Davis Tammy , Li Hangwen , Ivanov Ivan , Palapattu Ganesh , Pang Shen , Huang Jiaoti , Suraneni Mahipal , Tang Dean G.
Published: June 2012

Prostate cancer (PCa) is a heterogeneous malignancy containing different types of tumor cells. The cellular basis underlying PCa cell heterogeneity and functional importance of different PCa cell populations in maintaining tumor homeostasis and mediating castration-resistant progression remain poorly understood. By whole-genome microarray analysis, time-lapse videomicroscopy, serial tumor transplantations, and other functional assays, here we report the distinct molecular, cell biological, and tumor-propagating properties of PCa cells that express high (i.e., PSA+) and low (PSA−/lo) levels of PSA. PSA−/lo PCa cells are relatively quiescent and resistant to multiple stresses, exhibit high clonogenic potential, and possess long-term tumor-propagating capacity in intact male mice. They preferentially express stem cell-associated genes and epigenetic profiles and can generate PSA+ cells by either asymmetric or symmetric cell division. Of great clinic significance, PSA−/lo PCa cells can initiate robust tumor development in fully castrated hosts and survive experimental androgen-deprivation therapy. In contrast, PSA+ PCa cells, despite being highly tumorigenic in androgen-proficient hosts, possess more limited tumor-propagating capacity, mainly undergo symmetric division, and are sensitive to castration. Our data together suggest that the two populations of PCa cells appear to play differential roles in tumor maintenance and PSA−/lo cells may represent an important source of castration-resistant PCa cells. Our findings have important implications in understanding PCa cell heterogeneity, tumor response to the mainstay antiandrogen therapies, and emergence of castration-resistant PCa.

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 476. doi:10.1158/1538-7445.AM2011-476
Abstract 4774: Epimorphin inhibits mammary epithelial cell apoptosis through induction of IKBKE
Authors: Khauv Davitte , Cichon Magdalena , Radisky Derek
Published: June 2012

Epimorphin is a stromally produced factor that plays a role in normal mammary branching morphogenesis, but deregulated expression of epimorphin can have oncogenic consequences, although the oncogenic processes activated by epimorphin have not been elucidated. We had previously found that treatment of cultured mammary epithelial cells with epimorphin blocked activation of cell death pathways by a variety of apoptotic stimuli. These results implicated a potential role for epimorphin for inhibition of cellular apoptosis, a critical stage of tumor development. To identify potential mediators by which epimorphin could be affecting cell death pathways, we used a transcriptional profiling approach comparing mammary epithelial cells treated with epimorphin versus untreated cells. We found that epimorphin treatment led to significantly increased expression of IKBKE, which inhibits apoptosis through activation of NF-kappaB and which has recently been characterized as a key breast cancer oncogene. We found that epimorphin specifically blocks induction of apoptosis and activation of caspase-3 in cells treated with tumor necrosis factor-alpha, and that this activity was linked to epimorphin-mediated activation of IKBKE. We also found that knockdown of IKBKE blocked epimorphin-mediated induction of branching morphogenesis, implicating activation of IKBKE by epimorphin as a critical function for its normal morphogenic activities as well. These studies provide insight into an additional and unexpected linkage between mammary gland developmental processes and breast cancer progression.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4774. doi:10.1158/1538-7445.AM2011-4774
Abstract 4777: Loss of death receptor 5 expression in plasmacytic MALT lymphoma is associated with genetic aberrations
Authors: Anees Mariam , Horak Peter , Müllauer Leonhard , Streubel Berthold , Raderer Markus , Krainer Michael
Published: June 2012

Introduction: We investigated the expression profiles of TNF-Related Apoptosis Inducing Ligand (TRAIL) pathway components and the mechanisms underlying TRAIL-induced apoptosis in MALT lymphoma. In lymphoid malignancies these have been only explored in a few non Hodgkin lymphomas and in multiple myeloma so far. In view of this, we have performed a pilot study to assess the potential role of TRAIL-pathway in MALT lymphoma with and without plasmacytic differentiation.

Methodology: We assessed paraffin embedded specimens from 20 patients diagnosed with MALT lymphoma and treated at the Medical University of Vienna for the expression of the key components of TRAIL pathway including TRAIL, death receptors 4 and 5 (DR4 and DR5) and the long form of the FLICE inhibitory protein (FLIPL) by immunohistochemistry. In addition, we also investigated MALT-lymphoma associated genetic aberrations including t(11;18)(q21;q21), t(14;18)(q32;q21) involving IGH and MALT1, t(1;14)(p22;q32), t(3;14)(q14;q32) involving FOXP1 and IGH and trisomies 3 and 18 by reverse transcriptase polymerase chain reaction and fluorescence in situ hybridization.

Results: We observed a general loss of expression of key TRAIL components in MALT lymphomas with plasmacytic differentiation which were present in normal infiltrating plasma cells. DR4 expression was totally absent from 65.6% of the lymphoma tissues and only weakly present in the remaining 34.4%. DR5 was expressed by only 32.25% of the MALT lymphoma tissues. Out of these, DR5 was expressed by infiltrating regular plasma cells in 50% of cases, by plasmacytic lymphoma cells themselves in 40% and by both types of cells in the remaining 10%. Interestingly, MALT lymphomas expressing DR5 had a normal cytogenetic status while samples with absent or week DR5 expression displayed translocation t(11;18) and trisomy 3, 8 and/or 18. The DR5 loss was significantly correlated with cytogenetic abnormalities (R = -0.488, p=0.008). FLIPL was moderately expressed in 18.75% of our samples while TRAIL was present only in 6.25% of the tissues.

Conclusion: Loss of expression of TRAIL pathway components is a common event in MALT lymphomas with plasmacytic differentiation. Moreover, DR5 expression in particular correlates with the presence of MALT-associated cytogenetic anomalies.

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 4777. doi:10.1158/1538-7445.AM2011-4777
Abstract 4803: Epigenome signatures during gastric carcinogenesis detected by MBD-seq and RRBS technologies
Authors: Kim Hee-Jin , Haam Keeok , Kang Tae-Wook , Kim Seon-Young , Noh Seung-Moo , Song Kyu-Sang , Kim Yong Sung
Published: June 2012

DNA methylation plays an important role in the control of eukaryotic gene expression. Many tumor suppressor genes are silenced by aberrant DNA hypermethylation during carcinogenesis, while genome-wide DNA hypomethylation has been observed in human neoplasia, although the extent of this correlation still remains obscure. Hence DNA methylation profiling of a whole genome is essential to our understanding of its relevance for normal development and diseases including cancer. Recently two genome-wide DNA methylation assays combined with a next-generation sequencing (NGS) platform can be useful to establish the methylation map for a whole genome of cancer cell. One of the methods use affinity based assay to enrich for methylated DNA, called a ‘MBD-seq’ (methylated DNA binding domain sequencing: Nucleic Acids Res. 2010; 38: 391-9). Another one is ‘RRBS’ (reduced representation bisulfite sequencing: Nat Methods. 2010; 7: 133-6) which generates nucleotide resolution of DNA methylation from bisulfite sequencing library that enrich for CpG-dense regions by methylation-insensitive restriction digestion. In this study, we applied the two different methods to the same batch of genomic DNAs of normal gastric mucosa, intestinal metaplasia, and gastric tumor which were isolated microscopically using a laser microdissection system (PALM) with frozen clinical samples of one patient with intestinal type gastric cancer. The epigenome signatures during gastric carcinogenesis will be compared and presented here.

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 4803. doi:10.1158/1538-7445.AM2011-4803
Abstract 4808: Detection of aberrant DNA methylation in saliva samples as a predictor of recurrence in head and neck squamous cell carcinoma patients
Authors: de Carvalho Ana Carolina , Rettori Marianna M. , Maia Danielle C. C. , Carvalho Andre L. , Kowalski Luiz P. , Vettore Andre L.
Published: June 2012

Aberrant DNA methylation (hypermethylation) at CpG islands within promoter regions is an epigenetic mechanism involved in the transcriptional silencing of several tumor suppressor genes. The presence of hypermethylation is commonly reported in different human cancers and might be useful as a molecular marker for tumor cell detection and for early detection of tumor recurrence. Head and neck squamous cell carcinoma (HNSCC) is one of the most frequent types of cancer and the lack of early detection and the high incidence of locoregional recurrence lead to high mortality rates. Therefore, the identification of new molecular markers to be used as diagnostic and prognostic indicators is of paramount importance in reducing these recurrence rates. The aim of this study was to evaluate promoter hypermethylation of tumor suppressor genes using Quantitative Methylation-Specific PCR (Q-MSP) in tumor and salivary rinse samples as a mean to detect epigenetic alterations specific to HNSCC. Tumor samples were collected from 150 patients at the time of surgery while salivary rinses were collected before and after the last curative treatment and during the follow up (every 6 months for 2 years). The hypermethylation profile of 24 genes was analyzed and allowed the selection of a panel of 5 specific and sensitive genes. At least one of these genes was found methylated in 61% of the salivary rinse samples collected before treatment, suggesting that this panel could be useful as a diagnostic tool. Patients harboring aberrant DNA methylation of these genes in the post-treatment salivary rinse showed worse 3-year overall survival (p=0.035) and 3-year free from local recurrence survival (p=0.043). Thus, our results support the idea that the evaluation of gene methylation profile in saliva, a non-invasive method of sample collection, could be a good prognostic indicator of HNSCC recurrence.

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 4808. doi:10.1158/1538-7445.AM2011-4808
Abstract 481: In vivo imaging identifies that myf5+ embryonal rhabdomyosarcoma-propagating cells are dynamically reorganized during tumor growth
Authors: Ignatius Myron S. , Chen Eleanor , Elpek Natalie , Nielsen Petur , Linardic Corinne , Mempel Thorsten , Langenau David M.
Published: June 2012

Embryonal rhabdomyosarcoma (ERMS) is a devastating pediatric cancer with specific features of muscle differentiation. Here, we use a transgenic zebrafish model of RAS-induced ERMS and show that myf5+ ERMS cells possess self-renewal potential, confirming that ERMS is a cancer stem cell driven disease. The ERMS-initiating cell is molecularly similar to an activated satellite cell and expresses myf5, m-cadherin, and c-met. To directly visualize tumor-initiating cells in vivo, fluorescent transgenic zebrafish were created that express myf5-GFP, myogenin-h2b-mRFP, and mylz2-lyn-cyan. These transcription factors are expressed during distinct stages of muscle/ERMS development and transgenic reporter lines using these gene promoters allow self-renewing cells to imaged in live animals by confocal microscopy. myf5-GFP+ ERMS-initiating cells from early stage tumors lie in immediate proximity to muscle fibers where normal satellite cells reside. However, as tumors grow, the niche is greatly expanded with the number of myf5-GFP+ cells increasing by 10-fold per fiber. By late stages of tumor growth, myf5-GFP+ ERMS cells are re-localized into a new tumor-specific stem cell niche that is no longer associated with fibers and is separated from more differentiated myogenin+ and myogenein/mylz2 double positive tumor cells. Analysis of human ERMS showed that tumors also contain regional niches of differentiated and undifferentiated cells. Time-lapse imaging of live zebrafish showed that myf5-GFP+ ERMS cells move only locally within the tumor and remain largely confined to stable self-renewing niches. By contrast, myogenin+ cells move dynamically throughout tumors and colonize new areas for tumor growth by both migration through the tissue and entry into the vasculature system. Following colonization by myogenin+ cells, self-renewing myf5+ cells are recruited to new areas of tumor growth. Our findings reconcile the clinical observation that myogenin-positivity in RMS correlates with poor outcome, because it is these cells that intravasate into blood vessels, invade new areas of tumor growth, and recruit slow moving self-renewing cells to newly colonized areas. Taken together, our in vivo imaging studies provide unprecedented access to directly visualize tumor growth in real-time and to define the kinetics of self-renewal and tumor dissemination as has never been assessed in any experimental model.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 481. doi:10.1158/1538-7445.AM2011-481
Abstract 4815: Aberrant DNA hypermethylation of the ITIH5 tumor suppressor gene in acute myeloid leukemia
Authors: Oing Christoph , Jost Edgar , Dahl Edgar , Wilop Stefan , Osieka Rainhardt , Brümmendorf Tim H. , Galm Oliver
Published: June 2012

Acute myeloid leukemia (AML) is a clonal disorder resulting from uncontrolled proliferation of hematopoietic stem cells. Important genetic findings in AML comprise chromosomal translocations involving different transcription factors and activating point mutations in multiple signal transduction pathways. Hypermethylation of CpG islands within gene promoter regions in collaboration with deacetylation and other modifications of histone amino acids is associated with transcriptional inactivation and represents, in addition to genetic aberrations, an important mechanism of gene silencing in the pathogenesis of human cancer. Inter-alpha-trypsine inhibitors (ITIs) are proteases consisting of one light chain (bikunin) and two heavy chains (ITIHs), which stabilize the extracellular matrix (ECM). The putative tumor suppressor gene ITIH5 has previously been reported to be downregulated in association with aberrant DNA methylation in breast cancer. In this study, we determined the methylation status of the promoter-associated CpG island of ITIH5 in hematopoietic cell lines and primary AML patient samples. Methylation specific polymerase chain reaction (MSP) analysis revealed that the ITIH5 promoter region was hypermethylated in the AML cell lines HL60 and KG1a. Treatment of cell lines that carry a hypermethylated ITIH5 gene with the demethylating agent 5-aza-2’-deoxycytidine resulted in partial promoter demethylation. We then analyzed the ITIH5 methylation status in primary mononuclear cells obtained from 110 patients with newly diagnosed AML. The frequency of aberrant methylation among the primary patient samples was 14.5 % (16/110). Among clinical prognostic parameters, we found a significant positive correlation between hypermethylation of ITIH5 and elevated serum levels of lactate dehydrogenase (LDH, p=0.013) in univariate analysis, whereas no correlation was found for cytogenetics, FAB subtype, age, white blood cell count and overall survival. We conclude that promoter hypermethylation of ITIH5 is a novel epigenetic event in AML that may contribute to leukemogenesis by interfering with the interaction between the ECM and the leukemic clone. Further studies are warranted to elucidate the functional consequences of epigenetic dysregulation of ITIH5 in leukemogenesis.

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 4815. doi:10.1158/1538-7445.AM2011-4815
Abstract 4822: Nonsense mediated decay defines deleterious TP53 mutations and tumor aggressiveness in ovarian cancer
Authors: Ahmed Ahmed A. , Bast Robert C. , Bowtell David , Goldsmith Juliet
Published: June 2012

Genetic mutations leading to premature termination of protein translation, nonsense mutations, result in aberrant precursor mRNA processing and subsequent UPF1-dependent exosomal degradation of mRNA. The significance of this surveillance mechanism in controlling the expression of key mutated tumor suppressor genes in cancer in vivo has remained unclear. We have recently shown that TP53 mutations are almost invariably present in high-grade serous ovarian cancers (Ahmed at al., Journal of Pathology, 2010;221:49) and that about one third of such mutations are nonsense. We have now tested the hypothesis that nonsense mutations induce nonsense mediated decay resulting in TP53 mRNA depletion. We analyzed microarray expression profiling data from 136 epithelial ovarian cancers with known TP53 mutation status and found a strikingly statistically significant underexpression of TP53 mRNA transcript in cancers with truncating mutations (p<0.0001) compared to other types of mutations. This effect allowed the identification of a class of TP53-non-expressing serous epithelial cancers that comprised all TP53 truncating mutations. We next conducted a systematic analysis of 18 publically available expression profiling ovarian cancer studies published at the Gene Expression Omnibus database. We validated the results by showing that cancers that had nonsense mutations had a significantly lower TP53 expression irrespective of stage. Importantly, this systematic analysis of multiple independent data set established that lack of TP53 expression was, almost exclusively, a feature of high grade serous cancers and invasion as opposed to low grade disease or tumors of low malignant potential (p<0.0001 and p=0.002, respectively). Expression profiling analysis revealed that cancers with truncating mutations had a distinct gene expression signature compared to those with missense mutations. This signature was enriched for genes that regulated angiogenesis such as CSPG4 and metabolism. Surprisingly, however, the magnitude of expression differences was not high. Based on these results, we propose a model for the biogenesis of a subset of high-grade serous ovarian cancers that is defined by nonsense mediated decay of nonsense TP53 mutations.

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 4822. doi:10.1158/1538-7445.AM2011-4822
Abstract 4837: Integrated genome sequence, epigenome, and transcriptome map of bladder cancer development
Authors: Czerniak Bogdan , Majewski Taddeusz , Chung Woonbok , Limei Hu , Cogdell David , Bondaruk Jolanta , Zhang Shizhen , Lee Sangkyou , Lee Sooyong , Shen Li , Wei Caimiao , Yoo Suk Young , Choi Woonyoung , McConkey David , Weinstein John , Baggerly Keith , Issa Jean-Pierre , Zhang Wei , Scherer Steve E.
Published: June 2012

Genomic maps that track the development of human cancer from its in situ precursor conditions to invasive disease can facilitate the search for genes and genomic sequences involved in the development of cancer. The identification of those chromosomal regions and their positional target genes as well as non-coding sequences that provide growth advantage for the incipient preneoplastic conditions can provide novel insights on molecular mechanisms of cancer development. Such an approach is also critical for the identification of novel biomarkers as well as targets for preventive and therapeutic strategies.

We report on the construction of a high resolution whole-organ histologic and genetic map of bladder cancer development that tracks its progression from in situ precursor conditions to invasive clinically aggressive cancer using exome deep sequencing and 1M SNP-based Illumina genotyping combined with CpG island methylation and cDNA microarray technology platforms. This approach provided a high resolution integrated pattern of structural genome, epigenome, and transcriptome alterations that parallel the development of bladder cancer from early field effects to invasive disease.

By analyzing genome-wide patterns of structural genomic (copy loss or gain), epigenomic, and transcriptome changes, we found three major waves of alterations associated with growth advantage of successive clones reflecting a stepwise conversion of normal urothelial cells into cancer cells. In particular, this approach is significant for the identification of specific chromosomal regions as well as epigenetically and transcriptionally modified gene ontologies involved in early clonal expansion of intraurothelial neoplasia and their clonal evolution to carcinoma in situ progressing to invasive cancer. These studies suggest involvement of ras/raf gene network in early clonal expansion of intraurothelial neoplasia.

This map represents a prerequisite for specific studies on the mechanisms of incipient phases of bladder cancer development and should have a significant impact on the understanding of human carcinogenesis.

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 4837. doi:10.1158/1538-7445.AM2011-4837