bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 316: Keap1 and Nrf2 genetic mutations and polymorphisms: Associations with clinical outcome in endometrial cancer
Authors: Wong Tze Fang , Yoshinaga Kousuke , Monma Yasutake , Ito Kiyoshi , Niikura Hitoshi , Nagase Satoru , Yamamoto Masayuki , Yaegashi Nobuo
Published: June 2012

Background: Constitutive activation and increased expression of Nrf2 as a result of oncogenic mutations or other endogenous factors that cause derepression of Nrf2 by its cytosolic inhibitor, Keap1, contribute to tumor resistance to adjuvant treatment. As endometrial cancer generally has a lower response rate to adjuvant treatment, Keap1 and Nrf2 genes were sequenced to investigate their roles in endometrial cancer.

Materials and Methods: Tumor specimens from 105 individuals with endometrioid endometrial adenocarcinoma (Type I endometrial cancer) were sequenced. The specimens comprised 44 well-differentiated (FIGO grade 1), 38 moderately differentiated (FIGO grade 2) and 23 poorly differentiated (FIGO grade 3) tumors. Statistical analyses using the Fisher's exact test, Pearson's Chi-square test and Cox proportional hazards model were used to investigate the association of genetic mutations and haplotypes with patients’ annotated clinicopathologic characteristics.

Results: A total of ten novel Keap1 mutations were found in nine individuals, and two novel Nrf2 mutations were found in three individuals. One patient had two simultaneous Keap1 mutations, whereas two patients had the same type of Nrf2 genetic mutation. Two single nucleotide polymorphisms, rs1048290 and rs11545829 were found in high frequency in the present cohort. The non-synonymous genetic mutations and rs11545829 were not associated with patients’ clinicopathologic characteristics. In the adjuvant treatment subgroup, the rs1048290 c.1413C/G genotype was significantly associated with a better progression-free survival (hazard ratio, 0.25; 95% confidence interval [CI], 0.068 to 0.94; P=0.041). On multivariate analysis, rs1048290 was an independent prognostic factor for progression-free survival (hazard ratio, 0.16; 95% CI, 0.036 to 0.69; P=0.014).

Conclusion: Keap1 single nucleotide polymorphism rs1048290 may be a potential biomarker that enables individualized therapy using cytotoxic adjuvant treatment in endometrial 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 316. doi:10.1158/1538-7445.AM2011-316
Abstract 3163: Tissue-micro array based IHC analysis of mTOR activity in DLBCL
Authors: Sticz Tamas B. , Mark Agnes , Hajdu Melinda , Timar Botond , Nemes Karolina , Kopper Laszlo , Sebestyen Anna
Published: June 2012

Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous group of diseases with several subtypes with differing responses to therapy. The standard initial therapy for DLBCL continues using regimens like R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone), regardless of the subtypes. Targeted therapy offers a new approach to improve clinical responses. mTOR signaling has been shown to be activated in several lymphomas. mTOR inhibitors are being developed and are in clinical use in mantle cell lymphoma (MCL) therapy and clinical trials are ongoing in other high grade lymphomas as well. However, there is limited data about mTOR activity in different DLBCLs.

We evaluated immunohistochemical (IHC) results in biopsy materials from 79 DLBCL patients (42 females and 37 males, mean age 61 years), who were conventionally treated with R-CHOP, R-CEOP or CHOP therapy. Several antibodies (phospho-S6, phospho-p70S6K, phospho-mTOR, p-4EBP1, Mum1, CD10, bcl-6, bcl-2) were used and more than 700 IHC stainings were evaluated on TMA slides.

Mum1, CD10 and bcl-6 staining helped to distinguish between germinal center (GC) and non-germinal center B-cell derived DLBCL cases. Approximately 30% of cases were characterized as GC-derived DLBCL, which showed virtually no mTOR activity, as determined by phosphorylated S6 (p-S6) expression, the most sensitive marker (only weak p-S6 expression was detected in 2 cases). However, in about 80% of non-GC lymphoma cases, p-S6, p-mTOR, p-p70S6K and p-4EBP1 positivity was observed, which alludes to mTOR activity. Although the importance of mTOR activity is well demonstrated by mTOR mediated cyclinD1 expression in MCL, no statistical correlation was found between mTOR activity and the expression of pro-proliferative or anti-apoptotic factors (such as bcl-2 and bcl-6) in the examined DLBCL cases.

These results suggest that mTOR activity is characteristic in most non-GC derived DLBCLs. Similarly to MCL patients, those patients with poor survival may benefit from rapamycin derivatives or other treatments targeting mTOR. These rapalogs or other novel anti-mTOR agents may be used in addition to the regular R-CHOP therapy, however, patient selection criteria should be carefully considered.

Supported by OTKA-K68341 and OTKA-K81624 Projects.

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 3163. doi:10.1158/1538-7445.AM2011-3163
Abstract 3164: Decreased expression of GDP-mannose-4,6-dehydratase (GMD) and GDP-fucose transporter is associated with squamous histology in non-small cell lung cancers (NSCLCs)
Authors: Honma Rio , Kinoshita Ichiro , Miyoshi Eiji , Matsuno Yoshihiro , Shimizu Yasushi , Kaga Kichizo , Taniguchi Naoyuki , Dosaka-Akita Hirotoshi
Published: June 2012

We have previously reported that low expression of α1,6-fucosyltransferase (FT), an enzyme for the core fucosylation of N-glycans, is significantly more prevalent in squamous cell carcinomas compared with non-squamous cell carcinomas of the lung. GMD generates GDP-fucose from GDP-mannose, and is imperative for the synthesis of all fucosylated oligosaccharides. GDP-fucose is transported into the Golgi apparatus by GDP-fucose transporter to serve as a substrate of FTs.

In the present study, we examined expression of GMD and GDP-fucose transporter by immunohistochemistry in 156 surgically resected NSCLCs. High, moderate and low expression of GMD was found in 32 (20.5%), 32 (20.5%) and 92 (59.0%) NSCLCs, respectively. High/moderate, low and no expression of GDP-fucose transporter was found in 7 (4.5%), 23 (14.7%) and 126 (80.8%) NSCLCs, respectively. Low GMD expression was significantly more prevalent in tumors from men than in those from women (p = 0.02), in tumors from smokers compared with nonsmokers (p = 0.047), and in squamous cell carcinomas compared with non-squamous cell carcinomas (p = 0.0003) by the χ2 test. Multivariate logistic regression analysis for the correlation between GMD expression and various characteristics revealed a significant association between low GMD expression and squamous cell carcinomas, as compared with non-squamous cell carcinomas (low vs. moderate, p = 0.005; low vs. high, p = 0.02). Among biological characteristics of tumors studied previously in this cohort of NSCLCs, Ki-67 labeling index was significantly higher in tumors with low GMD expression than in those with high GMD expression (low vs. high, p = 0.003). Low expression of α1,6-FT was more prevalent in tumors with low GMD expression than in those with moderate or high GMD expression (p = 0.002). Low GDP-fucose transporter expression was significantly more prevalent in squamous cell carcinomas compared with non-squamous cell carcinomas (p = 0.003) by the χ2 test. GMD and GDP-fucose transporter expressions were not associated with survival. These results indicate that GMD and GDP-fucose transporter may be new markers of NSCLCs with specificity for histology.

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 3164. doi:10.1158/1538-7445.AM2011-3164
Abstract 3183: The role of G-protein coupled receptor-associated sorting protein 1 (GASP-1) in breast cancer progression
Authors: Tuszynski George , Rothman Vicki L. , Gutu Mohammed , Chang Frank
Published: June 2012

An innovative “2-D High Performance Liquid Electrophoresis” (2-D HPLE) technology was used to identify serum biomarkers associated with the earliest stage of breast cancer in addition to other more advanced stages. 2-D HPLE is a newly developed electrophoretic technology that separates 100's of serum albumin complexes on a polyvinyl membrane based on their surface charges. Association of cancer proteins (biomarkers) with pre-existing albumin complexes in the blood of cancer patients results in altered mobility on the membrane. Using 2-D HPLE we identified that G-protein coupled receptor-associated sorting protein 1(GASP-1) was present in the sera of patients with early stage disease but absent in sera of normal patients. GASP-1 has been shown to modulate lysosomal sorting and functional down-regulation of a variety of G-protein coupled receptors in neuronal cells. However, no reports have linked GASP-1 to breast cancer pathogenesis. GASP-1 was detected in tumor extracts of 7 cases of stage 2 and stage 3 breast cancer but not in adjacent normal tissue as revealed by Western Blot analysis using an antibody developed against a GASP-1 peptide identified by our 2-D HPLE technology. Using this antibody, we immunohistochemically detected over-expression of GASP-1 in all 59 cases of archived ductal breast carcinoma tumor samples. When GASP-1 was silenced in MB-231 breast carcinoma, the cells grew more than 5 fold slower than corresponding vector controls. These studies identify GASP-1 as a potential new serum and tumor biomarker for breast cancer and suggest that GASP-1 may be a novel target for development of breast cancer therapeutics.

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 3183. doi:10.1158/1538-7445.AM2011-3183
Abstract 3213: Induction chemotherapy for stage 4 gastric cancer and prognostic molecular markers
Authors: Ueda Shugo , Hattori Kengo , Inoue Yoshikage , Kadono Kentaro , Yoshimura Mio , Yoshida Masahiro , Yoshitomi Mami , Nomura Akinari , Hashida Hiroki , Terajima Hiroaki , Ozaki Nobuhiro , Fukushima Masakazu
Published: June 2012

The prognosis of gastric cancer with distant metastasis is very poor. Improvement of chemotherapy and investigation of molecular markers are required. We investigated the characteristics and the prognosis of patients with stage 4 gastric cancer with peritoneal or other distant metastases. 132 patients with stage 4 gastric carcinoma in Kitano hospital in between 2002 and 2009 were evaluated. The prognosis of the patients treated without chemotherapy was very poor. The prognosis of the patients with one factor of stage 4 was better than those with multiple factors. We tried induction chemotherapy with S-1 plus cisplatin for the patients without gastric bleeding or malignant gastric outlet obstruction. Our retrospective analysis demonstrated that induction chemotherapy improved the prognosis compared with adjuvant chemotheray after gastrectomy.

In order to develop molecular markers for chemotherapeutic efficacy for advanced gastric cancer, we investigated the gene expression in the gastric carcinoma before treatment. We identified novel markers of gastric cancer using focused microarray analysis, hypoxanthine phosphoribosyltransferase 1 (HPRT1) and transforming growth factor-alpha (TGF-α), low gene expression of which was associated with less malignant potential.

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 3213. doi:10.1158/1538-7445.AM2011-3213
Abstract 3224: Targeted non-invasive therapy of prostate cancer using fusogenic liposomes
Authors: Nesbitt Rae , Pink Desmond , Duncan Roy , Lewis John
Published: June 2012

Prostate cancer is the most common cancer in Canadian men. Most chemotherapeutic drugs do not preferentially target the tumour and therefore subject the patient's healthy cells to significant toxicity. There is therefore an urgent need for a novel strategy to deliver chemotherapeutic drugs specifically to the tumour. P14 is a fusion associated small transmembrane (FAST) protein which mediates efficient cell-cell interaction. When we incorporate this p14 FAST protein into liposomes we increase the fusion of the liposome to cell membranes. I hypothesize that targeted ablation of prostate cancer may be achieved by delivering chemotherapeutics encapsulated inside fusogenic liposomes targeted to the gastrin releasing peptide receptors. The objectives of the study are to i) validate the fusogenic properties of p14-containg liposomes ii) express and purify p14-bomesin fusion protein, iii) assemble targeted fusogenic lipsoomes iv) and assess the targeted ablation of human prostate cancer in a xenograft model. To validate the fusogenic properties of p14-containing liposomes in our cell lines, we encapsulated fluorescent dextran inside liposomes containing either no p14, mutant p14 (fusogenic incompetent) or an active p14. We incubated the liposomes on human fibrosarcoma cells (HT1080) and measured the uptake of fluorescent dextran using fluorescent microscopy. To construct a fusion protein, we used PCR amplification to fuse bombesin to the C-terminus of the p14 protein. Our analysis demonstrates that the incorporation of the p14 protein significantly increased the fluorescent dextran uptake in the cytoplasm of the HT1080 cells compared to the liposomes that contained no p14 and the mutant p14. Protein purification of the p14-bombesin fusion protein is still in progress. I propose to use these targeted fusogenic liposomes for future studies to evaluate the ability of bombesin-coated fusogenic liposomes to target prostate cells in vitro and deliver a toxic therapeutic payload to prostate tumours in vivo and assess tumour reduction.

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 3224. doi:10.1158/1538-7445.AM2011-3224
Abstract 3226: In vitro evaluation of a thermally targeted conjugate of a highly potent doxorubicin derivative
Authors: Opacak-Bernardi Teuta , Robinson Leslie , Ajaj Khalid Abu , Kratz Felix , Raucher Drazen
Published: June 2012

Doxorubicin is an anthracycline used in the treatment of many types of cancer. It intercalates into the strands of DNA to inhibit the progression of topoisomerase II, stopping the cell from replicating. The side effects, however, are severe and include neutropenia, alopecia, nausea, myelosuppression, and cardiotoxicity. Due to its nonspecific effect, high doses are needed to treat cancer cells. These high doses are inadvertently harmful to normal cells. n-Butyldiacatodoxorubicin (NBD) is a doxorubicin derivative that is converted in vivo to 2-pyrrolinodoxorubicin that is ∼ 1000-fold more active than doxorubicin. Because of its high potency, an efficient drug delivery system is needed in order to deliver NBD to the tumor site. To retain potent antitumor activity while reducing systemic toxicity, NBD was coupled to a thermally responsive macromolecular carrier. The macromolecular carrier is based on elastin-like polypeptide (ELP) which remains in solution at physiological temperature and accumulates in the tumor site when external hyperthermia is applied. The N-terminus of ELP was modified with the cell penetrating peptide (CPP) SynB1. SynB1 is a 19 amino acid peptide derived from porcine leukocytes which facilitates cellular uptake of the ELP carrier. NBD was attached to a terminal cysteine residue of ELP by conjugation of a 6-maleimidocaproyl hydrazone derivative of NBD. This NBD drug bears an acid-sensitive linker that is cleavable at the lysosomal/endosomal pH, which allows a controlled intracellular release of the drug. The ELP-delivered NBD inhibited MCF-7 cells growth in the nanomolar range. In addition, inhibition of cell proliferation was enhanced two-fold when hyperthermia was applied and cell proliferation was accompanied by apoptosis, which was enhanced 3-fold in MCF-7 cells when SynB1-ELP-NBD aggregation was induced with hyperthermia. These results suggest that the SynB1-ELP-NBD conjugate is a promising candidate for investigating its thermally targeting properties against solid tumors in animal models.

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 3226. doi:10.1158/1538-7445.AM2011-3226
Abstract 3242: New chemical tools for disrupting the MDM2/p53 protein-protein interaction: Identification, synthesis and biological evaluation of a novel class of MDM2/p53 inhibitors
Authors: Pernazza Daniele , Li Xiaolong , Lawrence Harshani R. , Guida Wayne C. , DuBoulay Courtney J. , Watts Shawn , Sebti Saïd M. , Chen Jiandong , Lawrence Nicholas J.
Published: June 2012

MDM2 and MDMX function as key regulators of p53 by binding to its N terminus, inhibiting its transcriptional activity, and promoting its degradation. In particular, MDM2 is overexpressed in some of human tumors, and with MDMX contributes directly to loss of p53 function during the development of nearly 50% of human cancers. Due to p53 inactivation, MDM2 in many tumors confers tumor survival; therefore it is an important molecular target for anticancer therapy. Several studies showed that reactivation of wild type p53 in tumor cells can be obtained by disrupting the MDM2/p53 interaction with peptidic, peptidomimetic, and small molecule p53-mimetics. Specific successful examples include the Nutlins and spirooxindole analogs (MI-219 and MI-63). Amongst the peptidic and peptidomimetic inhibitors examined to date, none is nearly as effective as Nutlins and MI-219 in tumor killing in vitro. Hence, new inhibitors against MDM2 and/or MDMX are needed: as cell permeable chemical probes of the p53 pathway in cancer biology, and as templates for structure-based rational design of p53 activators for future therapeutic use. As part of our drug discovery program to identify antagonists of the p53/MDM2 and p53/MDMx protein-protein interactions, a high-throughput in-silico screen of a 3.2 millions virtual library of compounds (from Schrödinger, Inc.). A physical restraint was applied during the screen, in order to mimic binding to the hydrophobic cleft of MDM2 normally occupied by three p53 side chains (F19, W23, and L26) that are critical for MDM2/p53 binding. The top highest ranked 160 compounds were then assessed for their ability to block p53 interaction with MDM2 and MDMx in an ELISA assay. This resulted in the identification of E12/DP3-117, a small molecule disruptor of the p53/MDM2 protein-protein interaction with an IC50 value of 47 ± 14 μM. We will report the synthesis and biological evaluation of focused libraries based on the initial hit and on compounds showing improved activity. Structure activity relationship studies around the hits will be disclosed as well as the outcomes of further rounds of chemical design and biological assessment. Binding of E12/DP3-117 to MDM2 is currently being assessed via co-crystallization and other biophysical techniques. We will describe the use of the crystal structure of p53-like mutant peptides in complex with the N-terminal domains of Mdm2, as the basis for rational design of more potent MDM2 small-molecule/peptide hybrid inhibitors.

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 3242. doi:10.1158/1538-7445.AM2011-3242
Abstract 3248: New inhibitors of the Shp2 phosphatase
Authors: Gevariya Harsukh , Ortiz Emmanuel D. , Chen Liwei , Daniel Kenyon , Lawrence Harshani R. , Guida Wayne C. , Sebti Said M. , Wu Jie , Lawrence Nicholas J.
Published: June 2012

The Shp2 protein tyrosine phosphatase (PTP) mediates signal transduction of growth factor receptors and regulates cellular activities critical to tumor growth and metastasis. In the basal state, the interactions between the N-SH2 and PTP domains keep the phosphatase in an auto inhibited closed conformation. Upon growth factor or cytokine stimulation, the SH2 domains of Shp2 binds to tyrosine phosphorylated docking proteins such as Gab1 and Gab2, which activates Src, Ras, and the Erk1/2 (Erk) mitogen-activated protein (MAP) kinase pathway. Shp2 gain-of-function mutations are found in leukemias and solid tumors and are linked to Noonan syndrome. Although Shp2 is involved in pathogenesis of human cancers, it is not clear how Shp2 mediates tumorigenesis. Shp2 is therefore believed to be an important enzyme for targeted cancer therapy. Since no potent and selective Shp2 PTP inhibitor is currently available for chemical biology studies and experimental therapy, we and others have been actively engaged in the search for such agents. In our continuing efforts to develop potent and selective Shp2 inhibitors to serve as both chemical probes to further our understanding of the role and signaling mechanisms of Shp2 in human diseases and as potential drugs for cancer therapy.

We will report the screening of a focused library of a set of commercially available salicylic acid derivatives using the in vitro DIFMUP phosphatase assay for their ability to inhibit the Shp2 phosphatase domain. Activity of hits was confirmed using the Biomol Green assay to determine inhibition of dephosphorylation of a Shp2 peptide substrate derived from EphR. One such hit was a thiazole containing salicylic acid that inhibits Shp2 with an IC50 (DIFMUP) of 100 µM. We will report the design and synthesis of salicylic acid libraries along with their benzoic acid counterparts. The most potent compound to date is HM2-08-4 which has an IC50 (DIFMUP) 1.1 µM. Emerging structure-activity relationships as well as modeling and X-ray studies will be discussed. The preliminary use of selected compounds as tools to probe the pharmacological inhibition of Shp2 and elucidate its role in cancer will be described.

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 3248. doi:10.1158/1538-7445.AM2011-3248
Abstract 3258: Development of novel ribonucleotide reductase inhibitors: A story from structural analysis to preclinical study
Authors: Zhou Bingsen , Su Leila , Yuan Yate-Ching , Hu Shuya , Yen Yun
Published: June 2012

The goal of this project is to develop new class inhibitors for Ribonucleotide Reductase (RR), a key enzyme for DNA synthesis. These inhibitors are more effective than existing small molecule therapies, and can overcome resistance from Hydroxyurea (HU), the only FDA approved drug for targeting RR-based cancers. In addition, this new class of inhibitors will ameliorate the severe iron chelating side effects associated with 3-Aminopyridine-2-Carboxaldehyde Thiosemicarbazone (3-AP, Triapine®), a compound that is currently been testing in human phase II clinic trials.

A lead compound, COH29 (US Patent No. 54435.8056.US01) with sub-micro molar range inhibition was developed through modification of a hit identified from screening a diverse compound library from NCI Developmental Therapeutics Program (DTP). COH29 demonstrated 90.2% inhibitory activity of recombinant human RRM2/RRM1 enzyme complex at 9 µM in vitro. Moreover, examine the cytotoxicity of COH29 in a NCI broad panel of 60 human cancer cell lines in vitro by 5 doses MTT cytotoxicity assay indicated COH29 show a good inhibition against cancer cells special to leukemia and ovarian cancer cells. Importantly, COH29 shows less toxicity to human normal fibroblast cells as compared to 3-AP.

Results from computer modeling and biophysical measurements suggest that COH29 interferes with the radical transfer pathway at the interface between RRM1 and RRM2. This represents a unique binding mechanism that is completely different from existing known inhibitors. Biacore binding analysis, computer docking, as well as NMR Saturation Transfer Difference (STD) studies have been performed and identified COH29 binding is specific to RRM2. These studies further confirm a V-shaped binding pocket of RRM2 with COH29. Preliminary data suggest that COH29 represents a promising new class of RR inhibitors with the advantages of (a) a unique mechanism and target specificity that interferes with the radical transfer pathway at the RRM1-RRM2 interface, (b) greater potency than HU in the sub-µM range of IC50, and (c) avoiding iron chelating-related side effects compared to 3-AP. Therefore, our objectives are to optimize the properties of COH29 into a viable candidate as a future anticancer drug targeting over expressed RR based cancers. (This project was supported by NIH grant CA 127541)

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 3258. doi:10.1158/1538-7445.AM2011-3258
Abstract 3268: Targeting Semaphorin signaling to inhibit tumor growth and metastatic spreading
Authors: Casazza Andrea , Kigel Boaz , Rolny Charlotte , Neufeld Gera , Tamagnone Luca
Published: June 2012

The Semaphorins and their receptors, Neuropilins and Plexins, were originally implicated as guidance signals in the development of the central nervous system. However, a growing body of evidence indicates that semaphorins may regulate tumor progression, by promoting or inhibiting tumor angiogenesis, tumor cell survival and metastatic spreading, in fact mediating a crosstalk between tumor cells and multiple stromal cell types in the surrounding microenvironment.

Here, we provide two examples of the multifaceted activity of semaphorins during tumor progression. We found that Semaphorin 3A (SEMA3A) inhibits primary tumor growth and its metastatic dissemination by employing three different experimental approaches in mouse tumor models: (i) over-expression of SEMA3A in tumor cells; (ii) systemic expression of SEMA3A following gene transfer in mice; (iii) tumor-targeted release of SEMA3A using gene-modified Tie2-expressing monocytes (TEMs) as delivery vehicles. In each of these experimental settings, SEMA3A efficiently inhibited tumor growth by disrupting vessel function and inducing tumor hypoxia and necrosis, without promoting metastatic dissemination.

Moreover, we have recently shown that another secreted semaphorin known to regulate angiogenesis, Semaphorin 3E (SEMA3E), is abundantly expressed in metastatic human tumors, where it promotes cancer cell invasiveness and metastatic spreading. Notably, this biological activity of SEMA3E depends on a proteolytic conversion by furin-like convertases, generating the active fragment “p61”-SEMA3E. In cancer cells, p61-SEMA3E induces the association of the receptor PlexinD1 with the oncogenic tyrosine-kinase receptor ErbB2, leading to ErbB2 activation and enhanced tumor invasion and metastasis. Here we show that a mutated uncleavable variant of SEMA3E (Uncl-SEMA3E) binds the receptor PlexinD1 but it is unable to trigger ErbB2 signaling in cancer cells and lacks any pro-metastatic activity. On the other hand, Uncl-SEMA3E functions as a potent anti-angiogenic factor and displays striking tumor-suppressor properties in vivo. In summary, SEMA3A and Uncl-SEMA3E are potent inhibitors of tumor angiogenesis and tumor growth which concomitantly block the metastatic spreading of tumor cells.

These data provide evidence that support interfering with semaphorin-mediated signals as a promising anti-cancer 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 3268. doi:10.1158/1538-7445.AM2011-3268
Abstract 327: Altered expression of insulin receptor isoforms in breast cancer
Authors: Jiaqi Huang , Morehouse Chris , Streicher Katie , Higgs Brandon W. , Gao Jin , Baffa Raffaele , Meggan Czapiga , Boutrin Anmarie , Brohawn Philip , Zhu Wei , LaVallee Theresa , Chang Yong , Richman Laura , Jallal Bahija , Yao Yihong
Published: June 2012

Human insulin receptor (INSR) isoform A (IR-A), one of the two primary isoforms of INSR, constitutes an important therapeutic target for the development of anticancer drugs. There is also crucial need to develop a quick and sensitive method to accurately measure each of the two isoforms in humans. A specific quantitative real-time PCR-based assay has been developed to distinguish IR-A from insulin receptor isoform B (IR-B). This assay provides greater sensitivity, reproducibility, and clinical applicability than previously established methodologies. We used this assay to evaluate the mRNA expression levels of the IR-A and IR-B as well as multiple tumor proliferation markers in breast tumor tissues. Results revealed a significant decrease in IR-B mRNA expression leading to a relative increase in IR-A mRNA proportion in tumor samples compared to normal breast tissue samples. We also identified a novel positive correlation between increased IR-A: IR-B mRNA ratio and cancer proliferation markers, including Ki67. Furthermore, we observed a statistically significant difference of IR-A: IR-B mRNA ratio between luminal-A and -B breast cancer subtypes. These results suggest that IR-A is the predominant isoform of insulin receptor in breast cancer and highlights the potential value of characterizing changes in the IR-A: IR-B mRNA ratio as a therapeutic indicator for drugs that target insulin growth factor.

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 327. doi:10.1158/1538-7445.AM2011-327
Abstract 3288: The anti-tumour efficacy of the novel peptide inhibitor of angiogenesis ALM-201
Authors: O'Rourke Martin , Valentine Andrea , McLean Estelle , Page Natalie , Cotton Graham , Robson Tracy , Hirst David , Harrison Timothy , James Iain
Published: June 2012

Neovascularization is critical to tumour growth and metastasis and this has led to the development of a number of marketed anti-angiogenic agents which target VEGF/VEGFR2 receptors, for clinical use in specific types of cancer. However, incomplete responses and/or resistance to these therapies has highlighted the need for new agents targeting alternative pathways. Here we describe the characterisation of a novel peptide derived from the natural protein FKBP-like binding protein (FKBPL), which has extremely potent anti-angiogenic activity, is very effective in mouse xenograft models at low doses, and exerts its effects through microtubule binding using CD44 as a cell-entry mechanism.

ALM-201 has been profiled in a range of human microvascular endothelial cell (HMEC-1) assays and potently inhibited migration, tubule formation and microvessel formation in vitro and in vivo. Although the peptide has a marked effect on migration, ALM-201 does not inhibit proliferation in a range of growth factor stimulated proliferation assays. Importantly, there is a significant disconnect between the pharmacokinetic and pharmacodynamic profiles of ALM-201 which allows for 3 q.d. dosing in mouse xenograft models. The peptide is well tolerated with no signs of toxicity observed in mouse xenograft models up to 80 days of dosing. The mechanism by which ALM-201 inhibits angiogenesis involves the cell surface receptor CD44, as determined by siRNA depletion of the receptor in migration assays. Furthermore, the peptide potently inhibits microtubule assembly and downstream signalling, thus promoting the anti-migratory phenotype.

In summary, ALM-201 is a novel, targeted microtubule binding agent which exhibits potent anti-angiogenic activity in vitro and in vivo. Pre-clinical development is in progress with a Phase 1 clinical study planned for 2011.

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 3288. doi:10.1158/1538-7445.AM2011-3288
Abstract 3290: REGN910, a fully-human, Ang2-specific monoclonal antibody, inhibits tumor growth as a monotherapy and dramatically potentiates the effects of VEGF Trap (aflibercept)
Authors: Daly Christopher , Castanaro Carla , Adler Alexander P. , Eichten Alexandra , Lalani Alshad S. , Papadopoulos Nicholas J. , Thurston Gavin
Published: June 2012

Inhibition of tumor angiogenesis via blockade of vascular endothelial growth factor (VEGF) has proven to be beneficial in several solid tumors. However, anti-VEGF therapies are not curative; thus, there is a significant opportunity to improve efficacy through combination therapy with agents that target other essential angiogenic pathways. Angiopoietin-2 (Ang2), a ligand for the endothelial cell-specific receptor Tie2, is selectively expressed in remodeling blood vessels such as those found in tumors. Furthermore, genetic and pharmacologic data indicate that Ang2 is essential for angiogenesis in several settings. These properties make Ang2 an attractive target for specific inhibition of tumor angiogenesis.

We generated a fully-human, Ang2-specific IgG1 monoclonal antibody (REGN910) using VelocImmune technology. REGN910 binds human Ang2 with very high affinity (KD ∼ 18 pM), and potently blocks its interaction with Tie2 (IC50 ∼ 50 pM), thereby inhibiting downstream signaling. In contrast, REGN910 exhibits no binding to Ang1, a Tie2 ligand that is broadly-expressed in normal tissues, and has no effect on Ang1/Tie2 signaling. In tumor xenograft models, REGN910 significantly inhibited the growth of several tumor types in a dose-dependent manner, including PC3 (prostate), Colo205 (colorectal) and A431 (epidermoid carcinoma). Furthermore, the combination of REGN910 plus the potent VEGF blocker aflibercept (VEGF Trap) inhibited tumor growth significantly better than the single agents in both the Colo205 and MMT models, promoting significant regression of Colo205 tumors. Consistent with the potent effect of this combination on tumor growth, REGN910 plus aflibercept reduced Colo205 tumor vascularity and tumor perfusion much more dramatically than the single agents, as monitored by histological and micro-ultrasound analyses. Thus, REGN910 significantly potentiates the effect of VEGF blockade on the function of tumor blood vessels, even in a tumor model (Colo205) that is very sensitive to anti-VEGF therapy. These results indicate that REGN910 is a promising candidate to selectively inhibit tumor angiogenesis, both as a single agent and in combination with anti-VEGF therapies.

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 3290. doi:10.1158/1538-7445.AM2011-3290
Abstract 3293: Activity and safety of an antiangiogenic peptide in spontaneous head and neck squamous cell carcinoma in cats
Authors: McNiel Elizabeth A. , Madrill Nicole J. , Esteves-Villanueva Jose O. , Dominguez Pedro A. , Dings Ruud , Mayo Kevin H. , Griffin Robert J.
Published: June 2012

Anginex is a rationally designed, synthetic peptide that inhibits proliferation of human and mouse endothelial cells and demonstrates anti-tumor activity in murine tumor models. The anti-tumor and anti-angiogenic activity of Anginex is attributable, at least in part, to its interaction with galectin-1, a carbohydrate binding protein. As an intermediate step in the clinical translation of Anginex and related anti-vascular agents, we are investigating the effects of Anginex in spontaneous feline head and neck squamous cell carcinoma (HNSCC). Feline HNSCC shares morphology, clinical behavior, and biologic features such as intratumoral hypoxia and expression of EGFR, COX-2, and mutant p53 with its human counterpart. Our objectives were to investigate the activity of Anginex in feline cells and provide evidence of its safety in a phase I trial in cats with HNSCC. To establish Anginex activity in vitro, we evaluated the effect of 24 hour exposure to Anginex doses ranging from 2.5 – 25 uM on proliferation of both feline aortic endothelial cells (FAECs) and feline HNSCC cells (SCCF1) using flow cytometry and labeling with propidium iodide and bromodeoxyuridine (BrdU). With increasing Anginex dose, we observed accumulation of FAECs in G1 and decreased uptake of BrdU. We observed no effect in SCCF1 cells. To investigate safety, cats were treated with Anginex in cohorts of at least three animals at doses of 1, 3, and 9 mg/kg daily for 5 days. Clinical, laboratory and histologic features were evaluated before and after treatment. There were no serious adverse events during treatment. Continuous variables including body weight and laboratory variables were compared before and after treatment using a Wilcoxon signed rank test. No statistically significant changes occurred in these parameters. These data indicate that Aniginex is active against feline endothelial cells specifically and appears to be safe in cats. We are currently investigating the effects of Anginex on tumor physiology and in combination with radiation therapy for feline HNSCC.

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 3293. doi:10.1158/1538-7445.AM2011-3293
Abstract 3297: Endothelial cells function as a niche to cancer stem-like cells by providing notch ligands in glioblastoma
Authors: Zhu Thant S. , Costello Mark A. , Hervey-Jumper Shawn , DiMeco Francesco , Vescovi Angelo L. , Heth Jason A. , Muraszko Karin M. , Fan Xing
Published: June 2012

Recent data show that endothelial cells function as a stem cell niche to promote CD133-positive cancer stem-like cells (CSLCs) self-renewal in glioblastoma (GBM). However, the molecular mechanism by which endothelial cells function as a stem cell niche is largely unknown. We had demonstrated recently that activation of NOTCH signaling is required for GBM CSLC propagation both in vitro and in vivo. To investigate if the acquisition of NOTCH activation in GBM CSLCs results from adjacent endothelial cells, we first examined the expression of NOTCH ligands JAG/DLL in primary GBM frozen samples. We found that JAG1, JAG2 and DLL4 are expressed mostly in endothelial cells adjacent to NESTIN- and NOTCH receptor-positive cancer cells. Some tumor cells also express JAG1, JAG2, and DLL1, but not DLL4, adjacent to NESTIN- and NOTCH-receptor positive cells in primary GBMs. Furthermore, we found that forced differentiated GBM cells from GBM neurospheres express a higher level of NOTCH ligands and a lower level of stem cell marker CD133, have reduced NOTCH activity, and are less tumorigenic in mice compared to GBM neurospheres. In addition, when we co-cultured GBM neurospheres with human brain microvascular endothelial cells (hBMECs) which express NOTCH ligands JAG/DLL, we found that hBMECs promote GBM neurosphere growth, increase the CD133-positive CSLC population and clonogenicity in vitro, whereas knocking down JAG1 or DLL4 in hBMECs abrogates hBMEC-induced GBM growth both in vitro and in vivo. Finally, we found that knockdown of JAG1 or DLL4 in hBMECs decreases growth of GBM intracranial xenograft in mice through reducing the CD133-positive population. In summary, we have demonstrated that NOTCH activation in GBM CSLCs is driven by juxtacrine signaling between tumor cells and surrounding endothelial cells, suggesting that targeting both CSLCs and their niche may provide an effective strategy to deplete GBM CSLCs.

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 3297. doi:10.1158/1538-7445.AM2011-3297
Abstract 3299: Targeting therapy-resistant glioma cells with novel compounds that inhibit action of survivin
Authors: Demir Habibe , Ray-Chaudhury Abhik , Li Tom , Li Chenglong , Nakano Ichiro
Published: June 2012

Introduction: Glioblastoma multiforme (GBM) is one of the most lethal diseases in adults. Despite intensive treatment with surgery, chemotherapy and radiation therapy, recurrence of tumors is inevitable in the majority of cases. It is therefore essential to determine the mechanism of establishment of therapy resistance in glioma cells and their effective targeting. Survivin is a member of the family of inhibitor-of-apoptosis (IAP) proteins, which functions as a key regulator of mitosis and apoptosis. Here, we sought to characterize survivin as a therapeutic target of GBM and identify a novel anti-glioma agent that inhibits survivin pathway.

Methods: Expression of survivin was analyzed immuohistochemically with 11 primary and recurrent GBM samples derived from the matched patients. In silico drug design was used to synthesize novel compounds that target dimerization of survivin. Effects of these compounds were tested with two distinct methods; (1) Treatment of patient-derived tumor spheres, and (2) direct injection into explants from surgical tissues of GBM.

Results: In 8 of 11 patients, survivin expression was increased in recurrent GBM samples compared to primary ones. Computational structure-based drug design suggested that two novel compounds, LLP3 and LLP9, inhibit survivin dimerization, which is essential for survivin function. Treatment of two patient-derived tumor spheres with 50 µM of LLP3 completely abolished sphere formation. The IC50 of LLP3 and LLP9 ranged between 25 and 50 µM, and between 40 and 70 µM, respectively, on 4 different GBM patient cells. Direct injection of LLP3 reduced proliferation and induced apoptosis in the tested GBM samples. Treatment of mouse tumors derived from GBM patient cells with LLP3 and LLP9 will also be described.

Conclusions: Upregulated survivin expression in recurrent tumors after chemoradiotherapy suggests that survivin is preferentially expressed in therapy-resistant GBM cells. Our novel compound, LLP3 strongly arrests tumor cell growth and induces apoptosis both in sphere cultures and in undissociated tumor blocks. Our results indicate a novel therapeutic strategy for GBM and, more specifically, for resistant recurrent tumors.

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 3299. doi:10.1158/1538-7445.AM2011-3299
Abstract 3306: Screening potential drug candidates for treatment of glioblastoma patients utilizing an in-vivo mouse/ rat model system
Authors: Passarini Jenna , Cleary John P. , Kumar Preetham , Newton Trisha , Sharma Michael , Sharma Cristian , Panunzalan Rubio R. , Gill Parkash , Sharma Sherven , Srivastava Rakesh , Shankar Sharmila , Sharma Jay P.
Published: June 2012

Cancer stem cells (CSCs) are thought to be critical for engraftment and long-term growth of many tumors, including glioblastoma multiforme (GBM). The cells are at least partially spared by traditional chemotherapies and radiation therapies, and finding new treatments that can target CSCs may be critical for improving patient survival. Human glioblastoma multiforme is a heterogenous tumor composed from tumor cells and small portion of cancer stem cells, which have a high tumorigenic potential and a low proliferation rate. Glioblastoma cancer stem cells are phenotypically similar to the normal stem cells, they express CD133 gene and other genes characteristic of neural stem cells and posses self-renewal potential. The CD133+ GBM CSCs have been isolated with Celprogen Media and ECM and characterized as chemo-/radio-resistant tumor-initiating cells which are responsible as one of the many factors involved in post-treatment recurrence. In order to explore the molecular properties of tumorigenic CD133+ GBM CSCs that resist treatment, we isolated CD133+ GBM CSCs from tumors that are recurrent and have previously received chemo-/radio-therapy. We found that the purified CD133+ GBM CSCs sorted from the CD133+ GBM CSC spheres express SOX2,CD44 and are capable of clonal self-renewal. We generated in-vivo model systems in mice and rats to screen potential drug agents for the treatment of GBM patients. We were capable of generating brain tumors in mice and rats within 20 days by subcutaneously injecting 1000 GBM CSCs at the hind limbs of the rodents. Within day 5 the GBM CSCs were already present in the brain's of the rodents. At days 10, 15 & 20 the GBM CSCs labeled with GFP were located in the brain. We tested various compound candidates in this model system and we were able to show decrease in the migration of the GBM CSCs in the brain when we started the treatment at day 10 compared to non-treatment groups. We were able to demonstrate all the gene signatures associated with GBM CSCs in this model system. We do see a down regulation of certain cancer promotes genes in the treatment group when compared to non-treatment groups. The drug candidates were tested for TGFβ and STAT pathways. The chemotherapeutic agents tested were Among the 300 compounds tested Adria, Taxol, DTIC, Thalidomide, Paclitaxel, Abraxane, Ertibux and Velcade. We were able to show 4 compounds that were effective against GBM CSC targeting selected pathways.

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 3306. doi:10.1158/1538-7445.AM2011-3306