bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 1906: Differential downstream effects of nicotinamide adenine dinucleotide (NAD) salvage pathway-inhibition in chronic lymphocytic leukemia (CLL) and multiple myeloma (MM).
Authors: Gehrke Iris , Poeppl Armando , Johnston James , Gibson Spencer B. , Banerji Versha
Published: August 2014

Chronic lymphocytic leukemia (CLL) and multiple myeloma (MM) represent the two most common hematologic malignancies in western countries. Up to date both diseases are mainly treated palliatively rather than curatively which reinforces the need for new treatment options. Targeting metabolism-associated pathways is a novel route for treatment of hematologic malignancies. Nicotinamide adenine dinucleotide (NAD) is not only a central molecule for metabolic processes such as ATP-generation, but is also involved in several other cancer-relevant events. The NAD-dependent enzyme Sirtuin 1 (Sirt1) has been described to function as an oncogene. Further, the rate-limiting enzyme for NAD-generation via salvage-pathways nicotinamide phosphoribosyltransferase (NAMPT) is upregulated in several cancers, making it an attractive metabolism-associated drug target.

We used the NAMPT-inhibitor FK866 to treat the MM-cell line IM9 and the CLL-like cell lines JVM3 and Mec2 as well as primary CLL-cells. Cellular energy status was assessed by means of ATP content and functioned as a measure of viability. Sirt1 levels were assessed by immunoblotting.

The MM-cell line IM9 was highly sensitive to FK866 with regard to ATP-reduction (50% reduction at 51.7nM). Also the tested CLL-like cell lines JVM3 and Mec2 were sensitive to FK866 with 50% reduction of ATP content at 76.6nM and 51.1nM, respectively. Primary CLL cells showed very heterogenous response. Some samples were highly sensitive with 50% reduction of ATP-content at 21.6nM, while others were completely resistant. We could not detect any correlation to available clinical data such as ZAP70 status or white blood cell counts. All three cell lines were positive for Sirt1. While the two CLL-like cell lines Mec2 and JVM3 showed a concentration-dependent downregulation of Sirt1 upon FK866 treatment for 72h, Sirt1 levels remained stable in the MM-cell line IM9. Primary CLL-cells showed various baseline levels of Sirt1 and a concentration-dependent downregulation upon FK866 treatment.

We conclude that FK866 activity in CLL-like cell lines involves downregulation of the NAD-dependent oncogene Sirt1, while FK866 activity in the MM-cell line IM9 is Sirt1-independent. In primary CLL-cells Sirt1 baseline levels may predict responsiveness to FK866 treatment.

Citation Format: Iris Gehrke, Armando Poeppl, James Johnston, Spencer B. Gibson, Versha Banerji. Differential downstream effects of nicotinamide adenine dinucleotide (NAD) salvage pathway-inhibition in chronic lymphocytic leukemia (CLL) and multiple myeloma (MM). [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1906. doi:10.1158/1538-7445.AM2013-1906
Abstract 1910: 3′UTR poly(T/U) tract deletions and altered expression of EWSR1 are a hallmark of mismatch repair-deficient cancers.
Authors: Piscuoglio Salvatore , Kishore Shivendra , Kovac Michal , Gylling Annette , Wenzel Friedel , Trapani Francesca , Altermatt Hans Joerg , Mele Valentina , Marra Giancarlo , Peltomaki Päivi , Terracciano Luigi , Zavolan Mihaela , Heinimann Karl
Published: August 2014

Background: Microsatellite instability (MSI), the genome-wide accumulation of DNA replication errors, is the hallmark lesion of DNA mismatch repair (MMR) deficient cancers, present in Lynch syndrome (LS)-related and 10-20% of sporadic colorectal (CRC), gastric and endometrial cancers. MSI testing is widely used to guide clinical management but the functional significance of MSI at distinct genic loci remains largely elusive. Here, we characterize a novel MSI target locus consisting of a mononucleotide (T/U)16 tract located in the 3’untranslated region (UTR) of the Ewing sarcoma break point region 1 (EWSR1) gene (EWS16T).

Methods: The diagnostic accuracy of EWS16T to identify MMR-deficient cancers was determined by analyzing 319 cancers (240 colorectal, 72 gastric, 7 endometrial) from two different populations. The functional consequences of EWS16T contractions were assessed in vitro (siRNA-mediated poly(A) site selection and pull-down assays) and in vivo (mRNA and protein expression by qPCR and tissue microarray analysis).

Results: The EWS16T locus discriminates MMR-proficient (n=128) from deficient (n=191) cancers with perfect diagnostic sensitivity (100%) and specificity (100%). Biochemical analyses indicate that EWS16T contractions alter poly(A) site selection by promoting SFPQ-mediated distal poly(A) site usage in EWSR1 pre-mRNAs and result in decreased mRNA as well as EWS protein expression. In contrast to their MMR-proficient counterparts (n=64), MMR-deficient, LS-related CRC (n=94) display altered subcellular localization of EWS (p<0.001).

Conclusions: The EWS16T locus represents a novel, quasi-monomorphic MSI target locus to accurately identify both hereditary and sporadic MMR-deficient cancers. Contractions therein affect multiple regulatory mechanisms implicating the RNA-/DNA-binding Ewing sarcoma protein in MSI-associated colorectal tumorigenesis.

Citation Format: Salvatore Piscuoglio, Shivendra Kishore, Michal Kovac, Annette Gylling, Friedel Wenzel, Francesca Trapani, Hans Joerg Altermatt, Valentina Mele, Giancarlo Marra, Päivi Peltomaki, Luigi Terracciano, Mihaela Zavolan, Karl Heinimann. 3′UTR poly(T/U) tract deletions and altered expression of EWSR1 are a hallmark of mismatch repair-deficient cancers. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1910. doi:10.1158/1538-7445.AM2013-1910
Abstract 1944: Evaluation of the prognostic value of miRNA-181b and its target identification and validation in colorectal cancers.
Authors: Bovell Liselle , Putcha Balananda-Dhurjati K. , Devadasan Divya , Bae Sejong , Grizzle William E. , Manne Upender
Published: August 2014

Background: microRNAs (miRNAs) are 19 to 24 nucleotide sequences that regulate cell proliferation, differentiation, and apoptosis. miRNA-181b is involved in tumor initiation and progression of several human malignancies including colorectal cancers (CRCs). Thus, we sought to determine the prognostic value of miRNA-181b in CRCs.

Methods: Expression of miRNA-181b was quantified, by quantitative PCR (q-RT-PCR), in normal (benign colonic epithelia) tissues and in their corresponding CRC archival tissue samples collected from 345 patients. The expression levels were correlated with patient overall survival. Putative molecular targets of miRNA-181b were identified by in silico analysis. miRNA-181b mediated, post-transcriptional regulation of these targets was assessed in CRC cell lines (SW480, HCT116 p53-/- and HCT116 +/+) by transfection studies. The targets were validated by measuring their mRNA expression levels, by use of qRT-PCR, in CRC tissues that exhibited elevated levels of miRNA-181b as well as by cloning techniques to assess a direct interaction between miRNA-181b and 3’UTRs of its target genes using luciferase assays.

Results: Survival analysis indicated that increased expression of miRNA-181b was associated with poor prognosis for CRCs (log rank, p=0.004). Fourteen putative molecular targets of miRNA-181b were identified by in silico analysis, and miRNA-181b mediated post-transcriptional regulation of these targets was validated in CRC cell lines by q-RT-PCR. Integrin alpha-3 was up-regulated, and BCL2LII and TNFα were down-regulated upon overexpression of miRNA-181b in vitro. Also, these targets were validated in CRC tissues that exhibited elevated miRNA-181b levels. The direct interaction of miRNA-181b with the target gene 3’UTRs was validated with luciferase assays.

Conclusions: These findings demonstrate that miRNA-181b regulates expression of Integrin alpha-3, BCL2LII, and TNFα; and is a prognostic marker for colorectal cancers.

Citation Format: Liselle Bovell, Balananda-Dhurjati K. Putcha, Divya Devadasan, Sejong Bae, William E. Grizzle, Upender Manne. Evaluation of the prognostic value of miRNA-181b and its target identification and validation in colorectal cancers. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1944. doi:10.1158/1538-7445.AM2013-1944
Abstract 1956: High-throughput screens identify microRNAs essential for HER2-positive breast cancer cell growth.
Authors: Leivonen Suvi-Katri , Kleivi Sahlberg Kristine , Makela Rami , Kallioniemi Olli , Borresen-Dale Anne-Lise , Perala Merja
Published: August 2014

MicroRNAs (miRNAs) are small non-coding RNAs regulating gene expression post-transcriptionally. Due to their capability to target multiple genes, often in a same pathway, miRNAs would be ideal candidates for therapeutic targeting. Here, our aim was to characterize the role of miRNAs in the regulation of HER2-signaling in breast cancer. HER2 is a receptor tyrosine kinase amplified in over 20% of human breast cancers and it regulates many important cellular processes, including cell growth and survival. HER2 mediates its signals by activating downstream pathways, such as phosphatidyl-inositol-3 kinase (PI3K)/AKT and the mitogen-activated protein kinases.

We performed miRNA gain-of-function assays by screening two HER2-positive cell lines (KPL-4 and JIMT-1) with a miRNA mimic library consisting of 810 human miRNAs. The levels of HER2, phospho-AKT, phospho-ERK1/2, cell proliferation (Ki67) and apoptosis (cleaved PARP) were detected with specific antibodies using protein lysate microarrays. In order to find the miRNAs most efficiently inhibiting HER2 signaling and proliferation as well as inducing apoptosis, we did rank product analyses through the whole data matrix. These analyses resulted in 38 miRNAs (q≤0.05). Among them were miR-491-5p, miR-342-5p and miR-744*, which were significantly (p≤0.05) down-regulated in HER2-positive breast tumors as compared to HER2-negative tumors. miR-342-5p appeared to specifically inhibit HER2-positive cell growth, as it had no effect on the growth of HER2-negative control cell line. Furthermore, higher expression of miR-342-5p was associated with better survival in breast cancer patients. We characterized also miRNAs directly targeting HER2 and identified eight novel miRNAs (miR-552, miR-541, miR-193a-5p, miR-453, miR-134, miR-498, miR-449b, and miR-449a) as direct regulators of the HER2 3’UTR.

Taken together, the miRNAs identified here are potent negative regulators of HER2 function and they may also play a role in vivo during breast cancer progression. These results suggest mechanistic insights in HER2 regulation in breast cancer and open potential new strategies towards prevention and therapeutic inhibition of HER2-positive breast cancer.

Citation Format: Suvi-Katri Leivonen, Kristine Kleivi Sahlberg, Rami Makela, Olli Kallioniemi, Anne-Lise Borresen-Dale, Merja Perala. High-throughput screens identify microRNAs essential for HER2-positive breast cancer cell growth. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1956. doi:10.1158/1538-7445.AM2013-1956
Abstract 1976: Targeting the PP2A tumor suppressor for the treatment of human pancreatic cancer.
Authors: Farrell Amy , Daniel Colin , Wang Zhiping , Allen-Petersen Brittany , Christensen Dale , Sheppard Brett , Lopez Charles D. , Sears Rosalie
Published: August 2014

Pancreatic cancer is a disease with a high rate of mortality, as it is generally diagnosed in the advanced stages when few effective treatments are available. Given the clinical aggressivity of this disease and the lack of good treatment options, the development of new therapeutic agents for the treatment of pancreatic cancer is of the upmost importance. Recent reports have suggested that disruption of several key signal transduction pathways is important for the development of pancreatic cancer. Many of these pathways are negatively regulated by PP2A, a phosphatase that plays a role in many cellular processes, and whose inhibition is essential for cell transformation. PP2A inhibition can occur through inactivation by viral oncogenes, mutation of specific subunits, or by overexpression of endogenous inhibitors, including SET (also known as I2PP2A) and Cellular Inhibitor of PP2A (CIP2A). Here, we show that SET and CIP2A are frequently overexpressed in human pancreatic cancer cells and primary patient samples. This overexpression results in decreased PP2A activity, and overexpression and stabilization of a key PP2A target, c-Myc. Knockdown of SET or CIP2A increases PP2A activity and reduces tumorigenic potential. Furthermore, inhibition of SET using a peptide mimetic (OP449) in pancreatic cancer cell lines increases PP2A activity, reduces migration and invasion, and decreases tumorigenic potential. Thus, antagonizing SET and CIP2A could be an innovative approach for the treatment of human pancreatic cancer.

Citation Format: Amy Farrell, Colin Daniel, Zhiping Wang, Brittany Allen-Petersen, Dale Christensen, Brett Sheppard, Charles D. Lopez, Rosalie Sears. Targeting the PP2A tumor suppressor for the treatment of human pancreatic cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1976. doi:10.1158/1538-7445.AM2013-1976
Abstract 1997: A gene expression profiling and molecular pathway analysis in early recurrence of patients with early stage lung adenocarcinoma.
Authors: Saji Hisashi , Tsuboi Masahiro , Shimada Yoshihisa , Kato Yasufumi , Hamanaka Wakako , Yoshida Koichi , Usuda Jitsuo , Ohira Tatsuo , Ikeda Norihiko
Published: August 2014

Background: Clinico-histopathological staging is insufficient to predict disease progression and clinical outcome in lung carcinoma. Here, we show that gene expression profiles and molecular pathways based on microarray and functional analysis can be used to predict early relapse in patients with early-stage lung adenocarcinoma.

Methods and Results: Based on the results of principal component analysis of a series of 24 samples of early-stage lung adenocarcinoma, there were two subgroups within the early-relapse group. The histological classification of all of group A was poorly differentiated, whereas only one of three cases in group B was classified as such. DAVID functional annotation analysis revealed 16 and 17 enriched pathways in groups A and B, respectively. Clusters of genes related to oncological or immunological functional signaling were found enriched in group A as were pathways such as cell adhesion molecules (CAMs), cell cycle, and antigen processing and presentation, whereas in group B the pathways were CAMs, T cell receptor signaling, cytokine-cytokine receptor interaction, toll-like receptor signaling, chemokine signaling, primary immunodeficiency, and natural killer cell mediated cytotoxicity. The CAMs pathway was found to be enriched in both groups.Conclusions: In this study, we present a comprehensive gene expression analysis and functional pathway analysis of early-stage lung adenocarcinoma, wherein we identified a distinct molecular pathway category, CAMs that correlated with early relapse of early-stage lung adenocarcinoma subclasses. This prognostic signature could be used to identify patients with early-stage high-risk NSCLC who might benefit from adjuvant therapy following surgery.

Citation Format: Hisashi Saji, Masahiro Tsuboi, Yoshihisa Shimada, Yasufumi Kato, Wakako Hamanaka, Koichi Yoshida, Jitsuo Usuda, Tatsuo Ohira, Norihiko Ikeda. A gene expression profiling and molecular pathway analysis in early recurrence of patients with early stage lung adenocarcinoma. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1997. doi:10.1158/1538-7445.AM2013-1997

Note: This abstract was not presented at the AACR Annual Meeting 2013 because the presenter was unable to attend.
Abstract 20: GIST-specific markers identified by comprehensive gene expression profiles.
Authors: Iwadate Manabu , Miyamoto Kohtaro , Ito Emi , Imai Jun-ichi , Sawada Naoki , Nakamura Izumi , Ohki Shinji , Watanabe Shinya , Waguri Satoshi , Takenoshita Seiichi
Published: August 2014

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal neoplasm of the gastrointestinal tract and highly express c-kit. Although surgical removal and molecularly targeted therapy are known to be effective, specific markers other than c-kit would be beneficial for histopathological classification, risk assessment, and treatment decision. To this end, we conducted a DNA-microarry analysis using approximately 900 tumor tissues obtained in Fukushima Medical University Hospital from 2007 to present. The database contained more than 30 kinds of tumors including 10 cases of GIST. We searched ∼32,000 genes on the array that showed expression ratio of >2.0 in GIST samples compared to others, and finally extracted 54 GIST-specific genes. In this study, we identified that cathepsin L mRNA is highly expressed in GISTs. Moreover, immunohistochemical analysis of 43 GIST specimens revealed that 86.0% (n = 37) were cathepsin-L positive, and this positivity was significantly correlated with c-kit positivity. From these results, we conclude that cathepsin L is highly expressed in GISTs.

Citation Format: Manabu Iwadate, Kohtaro Miyamoto, Emi Ito, Jun-ichi Imai, Naoki Sawada, Izumi Nakamura, Shinji Ohki, Shinya Watanabe, Satoshi Waguri, Seiichi Takenoshita. GIST-specific markers identified by comprehensive gene expression profiles. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 20. doi:10.1158/1538-7445.AM2013-20
Abstract 2002: Genomic landscape of copy number aberrations enables the identification of oncogenic drivers in hepatocellular carcinoma.
Authors: Wang Kai , Lim Ho Yeong , Shi Stephanie , Lee Jeeyun , Deng Shibing , Xie Tao , Zhu Zhou , Wang Yuli , Pocalyko David , Yang Wei J. , Rejto Paul A. , Mao Mao , Park Cheol-Keun , Xu Jiangchun
Published: August 2014

Cancer is a genetic disease with frequent somatic alterations in DNA. Study of recurrent copy number aberrations (CNAs) in human cancers would enable the elucidation of disease mechanisms and the identification of key oncogenic drivers with causal roles in oncogenesis. We have comprehensively and systematically characterized CNAs and accompanied gene expression changes in the tumors and their matched non-tumor liver tissues from 286 hepatocellular carcinoma (HCC) patients. Our analysis identified 29 recurrently amplified regions and 22 deleted regions with a high level of copy number changes, harboring established oncogenes and tumor suppressors, including CCND1, MET, CDKN2A and CDKN2B, as well as many other genes not previously reported to be involved in liver carcinogenesis. Pathway analysis of cis-acting genes in the amplification and deletion peaks suggests the alterations of core cancer pathways, including cell cycle, p53, PI3K, MAPK, Wnt and TGFβ signaling, in large proportions of HCC patients. We further credentialed two candidate driver genes, BCL9 and MTDH, from the recurrent focal amplification peaks and showed that they play a significant role in HCC growth and survival. In summary, we have demonstrated that characterizing the CNA landscape in HCC will facilitate the understanding of disease mechanisms and the identification of oncogenic drivers that may serve as potential therapeutic targets for the treatment of this devastating disease.

Citation Format: Kai Wang, Ho Yeong Lim, Stephanie Shi, Jeeyun Lee, Shibing Deng, Tao Xie, Zhou Zhu, Yuli Wang, David Pocalyko, Wei J. Yang, Paul A. Rejto, Mao Mao, Cheol-Keun Park, Jiangchun Xu. Genomic landscape of copy number aberrations enables the identification of oncogenic drivers in hepatocellular carcinoma. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2002. doi:10.1158/1538-7445.AM2013-2002
Abstract 203: Dynamic biochemical tissue analysis provides a unique method to detect functional in situ L-selectin ligands and unveils intercellular heterogeneity in colon cancer tissues.
Authors: Carlson Grady E. , Shirure Venktesh S. , Resto Vicente A. , Malgor Ramiro , Goetz Douglas J. , Burdick Monica M.
Published: August 2014

A growing body of evidence suggests that E-,P-, and L-selectin, a family of cell adhesion molecules, engage their ligands on colon cancer cells to initiate adhesion with the blood vessel wall at the secondary site during metastasis. This initial adhesion is a “rolling” adhesion in which selectin/selectin ligand bonds break and reform under forces in hemodynamic flow. Current standards for tissue analyses, such as immunostaining, do not assay for functional in situ selectin ligands, i.e., those that promote rolling. Recently, our lab developed a novel tissue analysis, termed dynamic biochemical tissue analysis (DBTA), which detects functional selectin ligands in situ by probing pathological tissues with selectin-coated microspheres. Due to the application of hydrodynamic flow in the assay, the selectin coated microspheres “roll” on tissue sections presenting functional selectin ligands. When colon cancer tissue sections of diverse histological classifications were probed with L-selectin-coated microspheres in DBTA, functional L-selectin ligands were detected (i.e., L-selectin microspheres rolled on the surface of the tissue sections). Rolling velocities were a function of hemodynamic shear stress, illustrating the unique kinetic and tensile properties of force-dependent L-selectin/L-selectin ligand bonds. More specifically, DBTA preserved the catch-slip behavior of selectin/selectin ligand bonds. That is, rolling became stabilized at physiologic shear stresses between 0.5-0.75 dyne/cm2, but outside this range microsphere rolling was increasingly erratic as bond breakage exceeded bond formation necessary to preserve adhesion. Differences in microsphere rolling velocities varied with position on the tissue surface and thereby demonstrated the heterogeneous expression of functional L-selectin ligands on colon cancer tissues. In summary, DBTA provides a unique method to detect functional in situ L-selectin ligands and unveils intercellular heterogeneity such that, with further development, DBTA may promote potential diagnostics and prognostics for cancer characterization.

Citation Format: Grady E. Carlson, Venktesh S. Shirure, Vicente A. Resto, Ramiro Malgor, Douglas J. Goetz, Monica M. Burdick. Dynamic biochemical tissue analysis provides a unique method to detect functional in situ L-selectin ligands and unveils intercellular heterogeneity in colon cancer tissues. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 203. doi:10.1158/1538-7445.AM2013-203
Abstract 2033: Identification of a novel genetic abnormality, the amplification of rictor (rapamycin-insensitive companion of mTOR), in a patient with non-small cell lung cancer.
Authors: Cheng Haiying , Piperdi Bilal , Schwartz Edward L. , Zhu Changcheng , Zhang Zhenfeng , Halmos Balazs , Miller Vincent , Perez-Soler Roman
Published: August 2014

Despite recent advances, clinically-relevant oncogenic drivers have not been identified in about half of lung adenocarcinormas. Here, we report rictor (rapamycin-insensitive companion of mTOR) amplification as a novel genetic abnormality in a young patient with non-small cell lung cancer. This male patient was a never smoker and was diagnosed with lung adenocarcinorma at the age of 18. He initially presented with refractory cough and persistent left lung lesions. Pathology was consistent with lung adenocarcinorma, poorly differentiated. Extensive molecular testing was negative for common genetic alterations in K-RAS, EGFR, ALK, HER2, RET, AKT, PIK3CA, BRAF and ROS1. His tumor was subsequently subjected to next generation DNA sequencing (FoundationOne, Foundation Medicine, Cambridge, MA) targeting a cohort of more than 180 cancer-related genes. This analysis identified rictor amplification of at least 6 copies as the sole DNA abnormality. Immunohistochemistry further documented rictor overexpression in the patient's lung tumor. The neoplastic lung tissue exhibited diffuse and strong cytoplasmic staining for rictor, compared to surrounding non-neoplastic tissues. Furthermore, the tumor tissue showed diffuse overexpression of phospho-S473 Akt, an essential downstream target of rictor.

Rictor is a key component of mTORC2 complex, where it modifies actin cytoskeleton organization, cell proliferation and survival. Activation of rictor signaling has been suggested to play critical roles in regulating cancer cell migration, invasion and metastasis in breast, ovarian, and colorectal cancers and gliomas. To our knowledge, this is the first report of rictor amplification in lung cancer. Moreover, we found that blockade of the rictor-mTORC2 pathway by siRNA-mediated rictor knockdown or with pharmacological inhibitors led to decreased phosphorylation of S473-AKT and growth inhibition in lung cancer cell lines. Thus, rictor amplification may represent a potential novel target in lung cancer. We will perform further studies to determine whether rictor amplification is a unique molecular subtype of lung cancer. Further, we hope to identify which targeted drugs are active against tumors with rictor amplification and overexpression.

Citation Format: Haiying Cheng, Bilal Piperdi, Edward L. Schwartz, Changcheng Zhu, Zhenfeng Zhang, Balazs Halmos, Vincent Miller, Roman Perez-Soler. Identification of a novel genetic abnormality, the amplification of rictor (rapamycin-insensitive companion of mTOR), in a patient with non-small cell lung cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2033. doi:10.1158/1538-7445.AM2013-2033
Abstract 2035: Anti-epileptic drug targets Ewing sarcoma.
Authors: Kayarthodi Shubhalaxmi , Fujimura Yasuo , Rungsrisuriyachai Kunchala , Fang Jinbo , Rao Veena , Reddy Shyam P.
Published: August 2014

Ewing sarcoma is a highly aggressive and metastatic bone or soft tissue tumor that affects children and adolescents. It is characterized by chromosomal translocations involving EWS gene and one of the ETS (Erythroblastosis virus E26 transformation-specific) families of transcription factors (ERG, FLI1, ETV1, ETV4, E1AF and FEV). All of the fusion genes juxtapose the EWS gene to an ETS related gene. Previously our laboratory has discovered several ETS oncogenes that have shown to play major roles in human cancers. ERG (ETS Related Gene), an important member of the ETS family genes, discovered by Drs. Reddy and Rao is shown to be involved in Ewing sarcoma. Our laboratory has previously demonstrated that ERG protein functions as a sequence specific transcriptional activator. Our preliminary results have shown that ERG and aberrant EWS-ERG proteins inhibit RXR transcriptional activation and apoptosis. These results suggest that transcriptional inhibition may play a major role in apoptosis function. Using a cell based assay system developed in our laboratory that measures the inhibitory activities of ERG proteins, we screened for known drugs that can reverse the inhibitory effects of RXR transcriptional activity. Since HDACs regulate nuclear receptors, we hypothesized that anti-epileptic drug, valproic acid and trichostatin-A (HDAC inhibitors) may reverse the inhibitory properties of EWS-ERG oncoprotein on RXR transcriptional activity and they can be used as therapeutic agents in Ewing sarcoma. Methods: Cell based assays were used to measure the RXR transcriptional activation function and in vivo assays were used to study the cell viability and apoptosis activity. Results: (1) Anti-epileptic drugs, valproic acid (VPA) and trichostatin-A (TSA) have shown to reverse the inhibitory effect of EWS-ERG on RXR transcriptional activity. (2) VPA and TSA inhibit the cell growth of Ewing sarcoma cells expressing EWS-ERG onco-protein. (3) VPA induce apoptosis in Ewing sarcoma cells. (4) VPA induce the expression of RXR target genes. Conclusion: Ewing sarcoma requires highly intensive chemotherapy along with surgery and/or radiation. Current therapies are associated with significant short and long term side effects. Hence new therapeutic approaches are needed. The above results suggest that the anti-epileptic drug VPA could be used as a potential treatment option for regulation of the function of EWS-ERG onco-protein. Thus, a promising drug with a new potential will have profound impact on prevention, management and treatment of Ewing family of cancers.

Citation Format: Shubhalaxmi Kayarthodi, Yasuo Fujimura, Kunchala Rungsrisuriyachai, Jinbo Fang, Veena Rao, Shyam P. Reddy. Anti-epileptic drug targets Ewing sarcoma. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2035. doi:10.1158/1538-7445.AM2013-2035
Abstract 2037: Establishment and characterization of paired mutant B-raf, vemurafenib-sensitive and -resistant patient-derived xenograft models.
Authors: Wick Michael J. , Vaught Teresa L. , Gamez Lizette , Meade Justin , Carden Skylar , Tolcher Anthony W. , Rasco Drew W. , Patnaik Amita , Miller Alexander , Drengler Ronald , Papadopoulos Kyriakos P.
Published: August 2014

Background: Vemurafenib is a recently approved anticancer therapy for B-RafV600E metastatic melanoma. Treatment with this agent increases overall patient survival compared with dacarbazine; however, most patients receiving vemurafenib progress within a year and are left with limited treatment options. Few validated screening tools exist to evaluate potentially beneficial therapies for these resistant/refractory patients. To address this deficiency we have generated a panel of paired mutant B-Raf vemurafenib-sensitive and -resistant patient-derived xenograft (PDX) models of metastatic melanoma and colorectal cancer. Each parent model was screened for activating mutations and all evaluated in vivo against vemurafenib. In addition, select model pairs were subjected to whole genome sequencing and RNA analysis to identify differences in genetic and expression profiles.

Methods: Establishment of parent models was previously described. Vemurafenib-resistant PDX models (PDX-VR) were generated by in vivo administration of clinical-grade vemurafenib at increasing concentrations over limited tumor passages. Parental vemurafenib-sensitive models were screened for activating mutations of fifty-two known cancer genes using a PCR-based assay with customized primers. DNA and RNA was extracted from select model pairs and profiled and compared for alterations.

Results: To date we have generated six B-RafV600E PDX-VR models (3 melanoma + 3 colorectal) with additional B-RafV600E and B-RafV600K PDX-VR models in development. In vivo studies evaluating vemurafenib in parent models reported notable tumor growth inhibition in all but one colorectal model (ST428), including tumor regressions in melanoma. PDX-VR models reported tumor growth similar to untreated controls at vemurafenib concentrations up to 150 mg/kg/day. Comparative analysis of paired models revealed some differences in DNA and RNA profiles.

Conclusion: We have generated a panel of paired mutant B-raf vemurafenib-sensitive and -resistant patient-derived xenograft (PDX) models representing metastatic melanoma and colorectal cancer available as validated screening tools to evaluate potentially beneficial therapies for vemurafenib-resistant/refractory patients.

Citation Format: Michael J. Wick, Teresa L. Vaught, Lizette Gamez, Justin Meade, Skylar Carden, Anthony W. Tolcher, Drew W. Rasco, Amita Patnaik, Alexander Miller, Ronald Drengler, Kyriakos P. Papadopoulos. Establishment and characterization of paired mutant B-raf, vemurafenib-sensitive and -resistant patient-derived xenograft models. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2037. doi:10.1158/1538-7445.AM2013-2037
Abstract 2062: The effects of a cell cycle inhibitory peptide fused to elastin-like polypeptide on pancreatic cancer cells with hyperthermia and its combination with gemcitabine.
Authors: Ryu Jung Su , Mikecin Ana-Matea , Raucher Drazen
Published: August 2014

Pancreatic cancer is the fourth most common cause of death in United States. Gemcitabine, a pyrimidine nucleoside analogue similar to cytarabine, has been used as a first line treatment for pancreatic cancer since 1997. However, its use has been limited by the side effects such as myelosuppression. So far, many efforts have been made to combine gemcitabine with other drugs, but have failed to prove superior to gemcitabine alone. This work describes the effects of genetically engineered elastin - like polypeptide (ELP) with the p21 Waf1/Cip1 - derived cell cycle inhibitory peptide (p21) on pancreatic tumor cells with or without gemcitabine. ELP is a thermally responsive polypeptide carrier that are soluble in aqueous solutions at physiological temperature (37 °C), but aggregate when the temperature is raised above its transition temperature (Tt, 42 °C). This allows it to be a promising thermally responsive therapeutic carrier that may be actively targeted to solid tumors by application of focused hyperthermia. For this study, we designed p21-ELP conjugates modified with the cell penetrating peptide, Bac, on the C-terminus of ELP. The anti-proliferative activity of p21-ELP-Bac was greater in with the presence of hyperthermia, and the combination therapy with gemcitabine showed the synergism on three pancreatic cancer cells - S2013, Panc-1, and Mia PaCa-2 in vitro. The reduced phosphorylated Rb level and the decrease of S- phase population in tumor cells treated with p21-ELP-Bac conjugates proves that the cytotoxicity which is based on cell cycle inhibition. In the S2013 pancreatic xenograft model, p21-ELP-Bac showed significant tumor growth inhibition in the presence of local hyperthermia; and this tumor growth inhibition was further enhanced upon co-treatment with gemcitabine. This combinatorial effect is expected to alleviate the toxicity of gemcitabine by reducing the dose in the clinics. Overall, our data suggest that thermal targeting of ELP-based therapeutic peptides to the pancreatic cancer cells is an effective and promising treatment strategy, especially in combination with gemcitabine.

Citation Format: Jung Su Ryu, Ana-Matea Mikecin, Drazen Raucher. The effects of a cell cycle inhibitory peptide fused to elastin-like polypeptide on pancreatic cancer cells with hyperthermia and its combination with gemcitabine. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2062. doi:10.1158/1538-7445.AM2013-2062
Abstract 2063: Synergistic anticancer activity of Sorafenib in combination with HS-173, a novel PI3K inhibitor against pancreatic cancer cells.
Authors: Yun Sun-Mi , Jung Kyung Hee , Lee Hyunseung , Park Byung Hee , Yan Hong Hua , Hong Soon-Sun
Published: August 2014

The K-RAS mutation, resulting in activation of the Raf/MEK/ERK pathway, has been implicated in pancreatic cancer development. And the PI3K/Akt pathway is highly activated in pancreatic cancer and considered to be a cancer hallmark. The principal objective of this study was to assess the synergic effect between Sorafenib (a Raf inhibitor) and HS-173 (a novel PI3K inhibitor) along with the underlying mechanism to gain insight into novel therapeutic strategies for treating pancreatic cancer. We first investigated the cytotoxic effect of co-treatment with Sorafenib and HS-173 using the Calcusyn program. Combined treatment with the two drugs synergistically inhibited the viability of Panc-1 cells (combination index < 1). Concomitantly, co-treatment with Sorafenib and HS-173 induced G2/M arrest and increased apoptosis with the loss of mitochondria potential. Apoptosis resulting from co-treatment with Sorafenib and HS-173 was accompanied by increased levels of cleaved caspase-3 and PARP as well as greater numbers of TUNEL-positive apoptotic cells compared to treatment with either drug alone. Furthermore, combined treatment with these drugs decreased the expression HIF-1α and VEGF, two factors that play an important role in angiogenesis. The anti-angiogenic effect of simultaneous treatment with Sorafenib and HS-173 was confirmed by observing the suppressed tube formation of VEGF-induced human umbilical vein endothelial cells and inhibition of blood vessel formation in a Matrigel plug assay in mice. Taken together, our study demonstrated that combined treatment with Sorafenib and HS-173 has a synergistic anticancer effect on pancreatic cancer cells, indicating that simultaneously targeting the Raf/MEK and PI3K/Akt pathways can induce a synergistic inhibitory effect on pancreatic cancers in which both pathways are activated. Based on the observations from our study, we suggest that the combined administration of these two drugs may be considered to be a new therapeutic regimen for treating pancreatic cancer.

Citation Format: Sun-Mi Yun, Kyung Hee Jung, Hyunseung Lee, Byung Hee Park, Hong Hua Yan, Soon-Sun Hong. Synergistic anticancer activity of Sorafenib in combination with HS-173, a novel PI3K inhibitor against pancreatic cancer cells. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2063. doi:10.1158/1538-7445.AM2013-2063
Abstract 2064: SF3B1 inhibitors sensitize head and neck squamous cell carcinoma to Bcl-xL inhibition by regulating Mcl-1 alternative splicing.
Authors: Gao Yang
Published: August 2014

This study explored the application of the alternative splicing of Bcl-2 family protein Mcl-1 in combination chemotherapy for head and neck squamous cell carcinoma (HNSCC) cell lines: meayamycin B (SF3b inhibitor) switched the pre-mRNA alternative splicing of Mcl-1 from anti-apoptotic to pro-apoptotic; the combination of meayamycin B with ABT-737 (Bcl-xL inhibitor) rapidly stimulated apoptosis in a panel of HNSCC cells, overcoming the HPV-16-mediated Mcl-1 over-expression.

Western blotting and semi-quantitative RT-PCR as well as qPCR afforded evaluation of the expression of Mcl-1 splicing variants at mRNA and protein levels. Apoptosis status was monitored by using caspase 3/7 activity assays and Annexin V/7-AAD staining. siRNA was used to specifically knock down HPV-16 E6 gene.

Meayamycin B exhibited 0.1-10 nM ED50 values in HNSCC cell lines that are mostly resistant to ABT-737. In HPV-16 positive HNSCC, E6 oncogene affords moderate resistance to meayamycin B. The combination of meayamycin B and ABT-737 synergistically induced apoptosis in HNSCC cell lines regardless of HPV status. These data demonstrate the potential of meayamycin B, both as a single agent and in combination with Bcl-xL inhibitors, for both research and targeted molecular therapeutic purposes for HNSCC.

Citation Format: Yang Gao. SF3B1 inhibitors sensitize head and neck squamous cell carcinoma to Bcl-xL inhibition by regulating Mcl-1 alternative splicing. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2064. doi:10.1158/1538-7445.AM2013-2064
Abstract 2085: The antileukemic drug nilotinib inhibits the invasive activity and the metastatic potential of colorectal cancer cells by targeting the receptor tyrosine kinase DDR1.
Authors: Tosti Priscillia , Leroy Cédric , Simon Valérie , Robert Bruno , Pierre Josiane , Sirvent Audrey , Roche Serge
Published: August 2014

Tyrosine kinases (TK) are frequently deregulated in human cancer and they play important roles in tumor progression. Since then, they have become valuable therapeutic targets and several inhibitors are currently used in the clinic. For example, the BCR-ABL inhibitor nilotinib is currently used for the treatment of patients with chronic myeloid leukemia (CML). Here we show that this antileukemic drug also inhibits invasive properties of colorectal cancer (CRC) cells. Inhibition was observed at the same dose-range for growth inhibition of CML cells. Nilotinib also strongly reduced liver metastasis induced by injection of CRC cells in the spleen of nude mice. Since we could not detect Abl deregulation in CRC cells, we speculated the involvement of an alternative target to be identified. Interestingly, a previous chemical-proteomic approach identified DDR1 as a novel target of nilotinib (Rix et al, Blood, 2007). DDR1 is a poorly-characterized TK and a receptor for collagen, a major component of the extracellular matrix. Accordingly, we found that DDR1 catalytic activity regulates cell invasion and metastasis of CRC cells. In addition, we demonstrate that nilotinib pharmacological activity is mediated by the inhibition of DDR1 in CRC cells: expression of the nilotinib resistant DDR1/T701I mutant renders CRC cells resistant to nilotinib treatment. Finally, we found that DDR1 catalytic activity is significantly increased in metastatic nodules compared to the primary tumor and the healthy tissue of the same patient. Altogether, these data suggest that the targeting of DDR1 by nilotinib may be of therapeutic value in metastatic CRC.

Citation Format: Priscillia Tosti, Cédric Leroy, Valérie Simon, Bruno Robert, Josiane Pierre, Audrey Sirvent, Serge Roche. The antileukemic drug nilotinib inhibits the invasive activity and the metastatic potential of colorectal cancer cells by targeting the receptor tyrosine kinase DDR1. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2085. doi:10.1158/1538-7445.AM2013-2085

Note: This abstract was not presented at the AACR Annual Meeting 2013 because the presenter was unable to attend.
Abstract 2088: NVP-BKM120 decreases cell survival and antagonizes resistance signals derived from protective tissue microenvironment by interfering with the Akt/FoxO3a/Bim axis in CLL cells.
Authors: Rosich Laia , Saborit-Vilarroya Ifigenia , Lopez-Guerra Monica , Xargay-Torrent Silvia , Montraveta Arnau , Aymerich Marta , Villamor Neus , Campo Elias , Perez-Galan Patricia , Roue Gael , Colomer Dolors
Published: August 2014

Phosphatidylinositol-3-kinase (PI3K) pathway is a key component of many cancers survival. Particularly, PI3K is constitutively activated in chronic lymphocytic leukemia (CLL) due to microenvironment signals, including stromal cell interaction, CXCR4 activation and B-cell receptor (BCR) triggering. Because of the importance of PI3K for CLL-microenvironment cross-talk and chemotherapy resistance, we investigated the activity of the NVP-BKM120, an orally available pan class I PI3K inhibitor.

Here, we show that NVP-BKM120 promoted mitochondrial apoptosis in primary CLL cells independently of common prognostic markers. At the molecular level, NVP-BKM120 blocked PI3K signalling, resulting in decreased phosphorylation of Akt and FoxO3a while downregulating Mcl-1 and inducing Bim. Importantly, selective knockdown of BIM rescued cells from NVP-BKM120-induced apoptosis. Moreover, NVP-BKM120 enhanced the activity of the BH3-mimetic ABT263 in CLL cells, leading to synergistic apoptosis induction. We also found that NVP-BKM120 inhibited BCR- and stromal-induced Akt activation as well as induced Bim in presence of BCR-derived and stromal survival signals. In stromal cocultures, NVP-BKM120 sensitized CLL cells towards bendamustine and fludarabine. Furthermore, NVP-BKM120 downregulated secretion of chemokines after BCR triggering and inhibited CLL cell chemotaxis and actin polymerization toward CXCL12.

Altogether, our data suggest that NVP-BKM120 displays a dual mechanism of action, directly decreasing cell survival and antagonizing survival and drug-resistance signals derived from protective tissue microenvironment.

Citation Format: Laia Rosich, Ifigenia Saborit-Vilarroya, Monica Lopez-Guerra, Silvia Xargay-Torrent, Arnau Montraveta, Marta Aymerich, Neus Villamor, Elias Campo, Patricia Perez-Galan, Gael Roue, Dolors Colomer. NVP-BKM120 decreases cell survival and antagonizes resistance signals derived from protective tissue microenvironment by interfering with the Akt/FoxO3a/Bim axis in CLL cells. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2088. doi:10.1158/1538-7445.AM2013-2088
Abstract 2103: XB05: a promising small molecule for cancer therapy.
Authors: Salipur Francesca R. , Reyes Elsa M. Reyes , Xu Bo , Smith Ned , Cai Jian , Hammond Gerald B. , Bates Paula J.
Published: August 2014

XB05 is synthetic small molecule which was serendipitously discovered to have potent anticancer properties. XB05 displays selectivity for malignant cells over non-malignant cells. Human myeloid leukemia cells (U937) and human lung cancer cells (A549) treated with XB05 show an increase in oxidative stress, DNA damage and a mixed apoptotic and necrotic mechanism of cell death. We conducted a COMPARE analysis to search for correlations between XB05 response and gene expression using publicly available microarray studies of the National Cancer Institute 60 cell line panel. This analysis uncovered a correlation between cell death in response to XB05 and expression of the transcription factor, SOX9. We find that SOX9 is differentially expressed across a panel of human lung cancer cell lines. MTT proliferation and clonogenic cell survival assays suggest that SOX9 expression positively correlates with the sensitivity of lung cancer cells to XB05. Furthermore, we show that siRNA knockdown of SOX9 recapitulates the phenotype of XB05-induced cell death, and that SOX9 may be downregulated at the protein level by XB05 treatment. Overall, these data demonstrate potent activity of XB05 against human cancer cells via a novel mechanism of action, and a potential role for SOX9 as a biomarker for selection and monitoring of therapy with XB05.

Citation Format: Francesca R. Salipur, Elsa M. Reyes Reyes, Bo Xu, Ned Smith, Jian Cai, Gerald B. Hammond, Paula J. Bates. XB05: a promising small molecule for cancer therapy. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2103. doi:10.1158/1538-7445.AM2013-2103