bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 659: Integrated therapeutic antibody development at the National Research Council of Canada
Authors: Jaramillo Maria L. , Marcil Anne , Durocher Yves , Gilbert Renald , Mullick Alaka , Kelly John , O'Connor-McCourt Maureen , Massie Bernard 
Published: May 2015

Abstract
Advances in genomics and antibody engineering have enabled the development of an innovative class of targeted therapies, namely therapeutic antibodies, for the treatment of diseases with significant unmet medical needs such as cancer. Therapeutic antibodies represent one of the largest and fastest growing classes of medications. The National Research Council of Canada (NRC) has built a chain of cutting edge technology platforms needed to discover, engineer and produce therapeutic monoclonal antibodies with the goal of partnering with industrial and academic centers to advance research and development of this important class of therapeutics.
Target Identification- Tumor targets were identified using a combination of proteomics, transcriptomics and bioinformatic approaches. Out of these lists, approximately 40 tumor targets were selected and over 3,000 antibodies of mouse and camelid origin were generated against these targets.
Antibody generation can be done conventionally, using the recombinant target protein produced using NRC's high efficiency cell expression platforms in CHO or HEK293 cells or by direct immunization with plasmid DNA constructs. Clone selection is carried out by ELISA and typically 50 antibodies/target are identified for further characterization.
Antibody characterization and validation- The affinities of the antibodies are determined by SPR biosensor analysis. Epitope mapping can be carried out so that representative antibodies can be selected for further validation in appropriate cell-based assays (many of which are established at NRC) and animal models.
Therapeutic antibody Optimization, Bioprocessing and Biomanufacturing- Therapeutic antibodies selected for development can be further optimized using antibody engineering technologies to humanize them and/or modify their glycosylation patterns to improve their effector function, pharmacokinetics, solubility and stability as well as reduce their immunogenicity. The NRC platform for large scale protein production has the capacity to manufacture up to 500 g of commercial grade antibody in a cGMP certified CHO cell line which is ready for transfer to CMOs .
Citation Format: Maria L. Jaramillo, Anne Marcil, Yves Durocher, Renald Gilbert, Alaka Mullick, John Kelly, Maureen O'Connor-McCourt, Bernard Massie. Integrated therapeutic antibody development at the National Research Council of Canada. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 659. doi:10.1158/1538-7445.AM2014-659
Abstract 660: Engineering strategies to control stoichiometry, site of conjugation, serum stability and effector functions of antibody-drug conjugates
Authors: Dimasi Nazzareno , Fleming Ryan 
Published: May 2015

Abstract
A promising approach to enhance the antitumor activity of antibodies and reduce the systemic toxicity of small molecule anti-cancer drugs is to covalently attach the small molecule to the antibody thus forming antibody drug conjugates (ADCs). Conventionally, ADCs are produced by chemical conjugation of drugs to antibodies through either lysine side chain amines or native cysteine sulfhydryl groups generated by reduction of interchain disulfide bonds. Both of these methods yield heterogeneous conjugates with complex biophysical properties. To limit these liabilities, we have designed, characterized, and validated antibody variants, which allow precise control of the site of conjugation and the drug load; such as two and/or four drugs per antibody can be site-specific conjugated. These engineered antibody variants can be efficiently and site-specifically conjugated with drug payloads at milligram and gram scales to yield homogenous ADC products. Engineered antibody variants described here retain antigen-binding affinities, FcRn binding, and have biochemical, biophysical and manufacturability properties similar to their non-engineered parent antibodies. Upon conjugation to highly cytotoxic drugs with anti-mitotic and/or DNA alkylating activities, the antibody variants have potent in vitro and in vivo anti-tumor activity. Furthermore, we describe ADCs vehicles that provide efficient scaffolds for site-specific conjugation of drugs while offering the opportunity to minimize off-target toxicities often observed with ADCs as a result of their binding to cells expressing Fc-gamma receptors. Finally, we show the impact of the identified sites for drug conjugation on the in vivo pharmacokinetic and safety profile of ADCs in rats. Our strategies for engineering ADCs with defined sites for conjugation, controlled drug loads, potentially decreased off-target toxicity, and optimal serum stability are broadly applicable to any full-length IgG or Fc-containing therapeutics as they involve the Fc constant domain of the antibody.
Citation Format: Nazzareno Dimasi, Ryan Fleming. Engineering strategies to control stoichiometry, site of conjugation, serum stability and effector functions of antibody-drug conjugates. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 660. doi:10.1158/1538-7445.AM2014-660
Abstract 662: Generation and characterization of antibodies specific for IL1RAP antigen to target quiescent and proliferating AML leukemic stem cells
Authors: Jiang Ping , Roy Sharmili , Huang Jen , Dao-Pick Trang , Lu Jennifer , Mishra Madhavi , Lin Jeffrey , Hsi Eric D. , Tressler Robert J. , Karsunky Holger 
Published: May 2015

Abstract
We have isolated and characterized blast cells and leukemic stem cells (LSCs) enriched from AML patients and identified cell surface targets selectively expressed on AML blast cells and LSCs and not their normal hematopoietic stem cell counterparts. A series of potent, specific, monoclonal antibodies (mAbs) have been generated against one of these AML LSC targets, IL1RAP. IL1RAP mAb clones were characterized for patient binding properties and also evaluated in in vitro cell based assays and in in vivo tumor xenograft models. These monoclonal antibodies demonstrated promising binding profiles in primary AML patients’ samples and robust anti-tumor activity in in vitro cell based assays and in vivo tumor xenograft models. Specifically, select clones have a high degree of specific binding to AML primary patient samples (&gt;90%), and specifically kill primary patient AML cells in complement-dependent cytotoxicity assays. These IL1RAP clones are being evaluated for inhibition of clonogenic potential of AML patient samples in vitro in colony forming assays and against normal clonogenic hematopoietic bone marrow derived stem cells. Select IL1RAP mAb clones evaluated in orthotopic AML tumor xenograft models have shown potent inhibition of tumor engraftment as well as significant tumor growth inhibition effects ranging from 80-90%. Because a key driver of LSC resistance is their quiescence, we also evaluated the antitumor effect of IL1RAP mAbs on quiescent AML cells in vitro. In summary, the patient binding profiles and in vitro and in vivo efficacy against AML cells indicates that targeting IL1RAP is a promising therapeutic approach for the treatment of AML and has the potential for effective eradication of AML LSCs and long term remission in the clinic.
Citation Format: Ping Jiang, Sharmili Roy, Jen Huang, Trang Dao-Pick, Jennifer Lu, Madhavi Mishra, Jeffrey Lin, Eric D. Hsi, Robert J. Tressler, Holger Karsunky. Generation and characterization of antibodies specific for IL1RAP antigen to target quiescent and proliferating AML leukemic stem cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 662. doi:10.1158/1538-7445.AM2014-662
Abstract 663: Development of a cancer-specific monoclonal antibody LpMab-2 specific for cancer-type podoplanin
Authors: Kato Yukinari , Kaneko Mika K. 
Published: May 2015

Abstract
Podoplanin is a platelet aggregation-inducing mucin-like sialoglycoprotein that is highly expressed in brain tumors, malignant mesotheliomas, testicular tumors, and lung, esophageal, or head and neck squamous cell carcinomas. Podoplanin has also been reported to be a marker to enrich tumor-initiating cells. We previously established a neutralizing monoclonal antibody (mAb), NZ-1, which inhibits the association between podoplanin and C-type lectin-like receptor-2 (CLEC-2) and blocks the podoplanin-induced platelet aggregation and tumor metastasis. A human chimeric mAb, NZ-8 possesses extremely high antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC), and showed high anti-tumor activities in several xenograft models. However, those mAbs also react with normal cells including lung type I alveolar cells, renal podocytes, and lymphatic endothelial cells throughout the body. Recently, we established the platform to produce a cancer-specific mAb (CasMab) by combining glycobiology and cell engineering technologies. Herein, we report a novel cancer-specific anti-podoplanin mAb, LpMab-2. In Western-blot analyses, LpMab-2 did not react with sialic acid-deficient podoplanin and O-glycan deficient podoplanin, which were expressed in Lec2 and Lec8 cells, respectively. In enzyme-linked immunosorbent assay using several deletion mutants of podoplanin, the epitope of LpMab-2 was shown to be included in 55-88 amino acids of podoplanin, although almost all anti-podoplanin mAbs recognize platelet aggregation-stimulating (PLAG) domain near the N-terminus. Analyses of glycopeptides produced by Edman degradation revealed that O-glycans were attached to glycosylation sites at residues Thr65, Thr66, Thr70, Ser71, Ser74, and Thr76 around LpMab-2 epitope. LpMab-2 did not react with podoplanin-negative cell lines, indicating that not only glycans but also amino acids of podoplanin are necessary for LpMab-2 reaction. In flow cytometric and immunohistochemical analyses, LpMab-2 reacted with tumor cells, but not with lung type I alveolar cells and lymphatic endothelial cells, suggesting that LpMab-2 recognizes the cancer-type conformation of podoplanin. Furthermore, human chimeric LpMab-2 also showed cancer-specific reaction against podoplanin. Taken together, a cancer-specific mAb LpMab-2 should be useful for molecular targeting therapy against podoplanin without side effects such as respiratory or renal failures and lymphatic edema. The CasMab-producing platform could lead to establishment of the side effect-reducing mAbs.
Note: This abstract was not presented at the meeting.
Citation Format: Yukinari Kato, Mika K. Kaneko. Development of a cancer-specific monoclonal antibody LpMab-2 specific for cancer-type podoplanin. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 663. doi:10.1158/1538-7445.AM2014-663
Abstract 665: Therapeutic targeting of breast cancer stem cells using PG-101 improves breast cancer survival
Authors: Wadehra Madhuri , Kiyohara Meagan 
Published: May 2015

Abstract
Since the original description of CSCs in solid tumors in 2003, emerging evidence suggests the presence of multiple breast CSC states (CD44+CD24-EpCAM+, ALDH+) that might be responsible for distinct processes in breast cancer progression such as metastasis, invasion, and proliferation. It has been hypothesized that CSCs contribute to the cellular heterogeneity within cancer, the metastatic spread, and eventual recurrence. As chemotherapy and radiation are relatively ineffective at targeting CSCs, therapeutic agents that target the relatively rare CSC population are highly needed.
To this end, we define another marker epithelial membrane protein-2 (EMP2) as a novel target for this population of cells. EMP2 is an oncogenic protein whose expression has been shown to correlate with tumor progression and survival in a number of human cancers including breast, ovarian, and endometrial tumors. Clinical data also revealed higher levels of EMP2 in metastatic lesions compared to primary tumors and high expression in triple negative breast cancer. In this study, we show new evidence that EMP2 is highly expressed in CSCs and regulates their proposed functions, namely mammosphere formation and invasion. Moreover, in vivo modulation of EMP2 expression in both triple negative and HER2 positive tumors show that EMP2 promotes ALDH1 expression as well as increases tumor load.
We have recently developed a novel IgG1 monoclonal antibody to EMP2 termed PG-101, and we have shown that this therapy reduces primary. We now have evidence that PG-101 treatment in the primary tumor is sufficient to reduce secondary tumor formation in triple negative breast cancer cells on the order of 1:20,000 compared to the control treated mice. To extend on the benefits of PG-101, we have combined it with docetaxel in an effort to mimic the clinical setting given that the vast majority of patients treated in the neoadjuvant setting have a taxane as part of the regimen. Data using triple negative xenografts show that PG-101 in combination with docetaxel can cure up to 80% of animals treated. This effect is lasting as these mice have shown no rebound in tumor load more than 2 months following the last treatment. Collectively, these results show that PG-101 therapy has the potential to revolutionize the outcomes for women with breast cancer.
Citation Format: Madhuri Wadehra, Meagan Kiyohara. Therapeutic targeting of breast cancer stem cells using PG-101 improves breast cancer survival. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 665. doi:10.1158/1538-7445.AM2014-665
Abstract 674: ODM-201 - New generation androgen receptor inhibitor targeting resistance mechanisms to androgen signalling-directed prostate cancer therapies
Authors: Moilanen Anu-Maarit , Riikonen Reetta , Kallio Pekka J. 
Published: May 2015

Abstract
Androgen receptor (AR) mutations have been described to emerge in response to prostate cancer treatment with first generation AR antagonists, resulting in broadened ligand specificity and AR antagonist-to-agonist switch. Second-generation AR antagonists enzalutamide and ARN-509 function as antagonists in the presence of AR overexpression. They express high clinical efficacy in castration resistant prostate cancer (CRPC) but eventually resistance will emerge.
Recently, a F876L missense mutation in the ligand-binding domain of AR has been described that confers resistance to enzalutamide and ARN-509 in preclinical models of prostate cancer. AR F876L mutation has also been identified in plasma DNA from ARN-509-treated CRPC patients with rising PSA.
ODM-201 is a new generation AR inhibitor with high anticancer activity in patients with CRPC and has unique properties compared to first and second generation antiandrogens. ODM-201 and its major metabolite bind to wt AR with excellent affinity (Ki 8 and 9 nM, respectively) and selectivity. In functional cell-based assays, ODM-201 functions as antagonist in highly AR overexpressing cells and does not induce AR T877A or W741L transcriptional activity. In contrast to enzalutamide and ARN-509, ODM-201 and its metabolite have been found to potently inhibit the activity of AR F876L while enzalutamide and ARN-509 were agonistic.
ODM-201 is a promising new generation AR inhibitor for the treatment of advanced prostate cancer with superior antiandrogenic activity in preclinical models of AR function.
Citation Format: Anu-Maarit Moilanen, Reetta Riikonen, Pekka J. Kallio. ODM-201 - New generation androgen receptor inhibitor targeting resistance mechanisms to androgen signalling-directed prostate cancer therapies. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 674. doi:10.1158/1538-7445.AM2014-674
Abstract 68: Tumor operational signaling pathways in an Nf1 mutant mouse model system
Authors: Braunstein Steve , Mroue Rana , Huang Brian , Bandyopadhyay Sourav , Nakamura Jean 
Published: May 2015

Abstract
Purpose/Objectives: NF1 is recognized as a tumor suppressor, via its role as a Ras GTPase activating protein. However, the precise mechanisms critical to tumor development in NF1 patients remain unclear. NF1 heterozygosity confers susceptibility to tumorigenesis, promoted by genotoxins such as radiation. We mutagenized Nf1 heterozygous mice using radiation to generate a diverse panel of Nf1 null tumors. Using these novel reagents we interrogated signaling pathways essential for tumor development and propagation towards identification of potential targets for therapeutic approaches.
Materials/Methodology: Cell lines were derived from solid tumors developing after focal irradiation of Nf1 heterozygous mice. Radiation-induced tumors included mammary carcinomas, squamous carcinomas, and sarcomas. We employed a high-throughput toxicity screen of 94 conventional and targeted FDA-approved chemotherapeutics directed across diverse core cellular signaling pathways. Drug sensitivity profiles were determined by quantifying cell numbers after a 72 hour drug exposure, and tumor cell lines, non-transformed wild-type and Nf1 null MEFs, and mutant Ras-transformed cell lines (added as controls) were compared. Validation of identified drug sensitivities was performed by enzyme activity assays, phosphoprotein analysis, and soft-agar colony formation.
Results: Nf1 mutant tumors failed to demonstrate a common drug sensitivity signature, but instead revealed a heterogeneous pattern of differential sensitivities, with subgroups clustering independent of tumor histology. However, radiation-induced Nf1 null tumor lines exhibited increased sensitivity to inhibition of the Ras-Erk and PI3K-mTOR axis as compared to non-transformed controls. Enhanced sensitivity to agents targeting cell cycle and survival pathways was also observed selectively within the Nf1 null tumor cell lines.
Conclusions: These studies indicate that Nf1 null tumors, even those of the same histology, do not intrinsically share a signature sensitivity profile to pharmacologic inhibition. This suggests that therapeutic targeting of signaling pathways in Nf1 mutant tumors is not likely to be defined strictly by Nf1 loss alone. Notably, these Nf1 null tumors evidence varied operational dependence upon PI3K-mTOR and Raf-MEK activity. Current efforts are directed towards further resolving essential mediators, with the goal of more precisely defining signaling pathways which drive progression of the malignant state.
Citation Format: Steve Braunstein, Rana Mroue, Brian Huang, Sourav Bandyopadhyay, Jean Nakamura. Tumor operational signaling pathways in an Nf1 mutant mouse model system. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 68. doi:10.1158/1538-7445.AM2014-68
Abstract 683: Sensitizing tumors to pro-oxidant therapy by inhibiting gamma-glutamyl transpeptidase
Authors: Hanigan Marie H. , Wakeham Nancy , Wickham Stephanie , Terzyan Simon S. 
Published: May 2015

Abstract
We have reported that 73% of ovarian tumors express the cell surface enzyme gamma-glutamyl transpeptidase (GGT). Clinical studies have shown a poorer prognosis for ovarian tumors that are GGT-positive compared to GGT-negative tumors. GGT-positive tumors are able to use the glutathione in the interstitial fluid as an additional source of cysteine, the limiting component of intracellular glutathione synthesis in tumors. The concentration of cysteine/cystine in standard tissue culture media is more than 3 times the concentration in interstitial fluid. In this study we show that in studies of cultured cells, the high concentration of cysteine in tissue culture media obscured the role of GGT expression in drug resistance. However, culturing human ovarian tumor cells in tissue culture media containing physiological concentrations of cystine and glutathione demonstrated that the supply of cysteine/cystine regulates intracellular glutathione concentrations. In these studies, inhibition of GGT blocked the use of extracellular glutathione as a source of cysteine and sensitized the tumors to cisplatin, carboplatin and melphalan. Inhibiting GGT in patients would also inhibit GGT in the kidney resulting in the excretion of glutathione in the urine and depletion of cysteine from serum and interstitial fluid. As a result, inhibition of GGT in patients would sensitize both GGT-positive and GGT-negative tumors to pro-oxidant chemotherapy. Clinical application of this therapeutic strategy is limited by the fact that most inhibitors of GGT are glutamate analogs and too toxic for use in humans. We discovered a non-glutamate analog that is an uncompetitive inhibitor of GGT, and are developing more potent, non-toxic GGT inhibitors. We recently published the crystal structure of human GGT. We have now also solved the structure of the substrate-bound enzyme, the form of the enzyme to which our uncompetitive inhibitors bind. Using structure-based drug design and our physiologically relevant tissue culture system we are designing new GGT inhibitors and evaluating them for their ability to sensitize tumors to chemotherapy regimens used in the clinic. Supported by an Institutional Development Award (IDeA) from the National Institutes of Health under grant P20GM103640.
Citation Format: Marie H. Hanigan, Nancy Wakeham, Stephanie Wickham, Simon S. Terzyan. Sensitizing tumors to pro-oxidant therapy by inhibiting gamma-glutamyl transpeptidase. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 683. doi:10.1158/1538-7445.AM2014-683