bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 925: Helicobacter pylori induces phosphorylation of STAT3 at Ser727 to promote mitophagy in gastric cancer cells
Authors: Piao Juan-Yu , Lee Hee Geum , Kim Su-Jung , Kim Do-Hee , Na Hye-Kyung , Surh Young-Joon
Published: August 2015

Chronic Helicobacter pylori (H. pylori) infection has been considered to be one of the high risk factors of gastric cancer, but the exact mechanism underlying H. pylori-mediated carcinogenesis has not been completely elucidated. Constitutive activation of the signal transducer and activator of transcription 3 (STAT3) is implicated in inflammation-associated carcinogenesis. In a canonical STAT3 pathway, phosphorylation of STAT3 at Tyr705 is a major event of STAT3 activation. In the present study, we found that H. pylori induced phosphorylation of STAT3 at not only Tyr705 but also Ser727. Notably, STAT3 Ser727 phosphorylation occurred at late time independently of Tyr705 phosphorylation followed by migration to mitochondrion. It has been reported that mitophagy is a specialized form of autophagy that removes damaged mitochondria to maintain efficient cellular metabolism and reduces cellular stress. In our study, H. pylori infection induced mitophagy with upregulation of LC3 (microtubule-associated chain3), which is an autophagy marker, in mitochondria. H. pylori-induced Ser727 phosphorylation appears to regulate expression of LC3 based on the experiment utilizing the STAT3 mutant vector in which Ser727 is replaced by alanine, suggesting a potential link between mitophagy and STAT3 phosphorylation at Ser727. Furthermore, we found that STAT3 phosphorylated at Ser727 bound to Grim19 which is a component of complex I and heat shock protein 90 in mitochondria. How this binding contributes to mitopagy is under investigation. In conclusion, H. pylori induced STAT3 phosphorylation at Ser727 to promote mitophagy

Citation Format: Juan-Yu Piao, Hee Geum Lee, Su-Jung Kim, Do-Hee Kim, Hye-Kyung Na, Young-Joon Surh. Helicobacter pylori induces phosphorylation of STAT3 at Ser727 to promote mitophagy in gastric cancer cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 925. doi:10.1158/1538-7445.AM2015-925
Abstract 947: An antibody drug conjugate (ADC) directed to lymphocyte antigen 6 complex, locus E (LY6E) delivers targeted chemotherapy to a wide range of solid tumor malignancies
Authors: Asundi Jyoti , Crocker Lisa , Tremayne Jarrod , Polakis Paul , Firestein Ron
Published: August 2015

Chemotherapies are limited by a narrow therapeutic index resulting in suboptimal exposure of the tumor to the drug and acquired tumor resistance. One approach to overcome this is through Antibody Drug Conjugates (ADCs); that facilitate greater potency via target specific chemotherapy delivery. In this study, we used a bioinformatics approach to identify Lymphocyte antigen 6, locus E, (LY6E), an interferon-inducible glycosylphosphatidylinositol (GPI)-linked cell membrane protein, as a promising ADC target. Immunohistochemical analysis revealed LY6E was overexpressed in a number of tumor types, such as, breast, including triple negative breast cancer, lung, gastric, ovarian, pancreatic and head/neck carcinomas. Characterization of the endocytic pathways for LY6E revealed rapid uptake of the LY6E specific antibody into cells leading to lysosomal accumulation. Consistent with this, a LY6E specific ADC inhibited in vitro cell proliferation and produced durable tumor regression in vivo in high LY6E expressing cancers. Our results identify LY6E as a highly promising molecular ADC target for a variety of solid tumor types with current unmet medical need.

Citation Format: Jyoti Asundi, Lisa Crocker, Jarrod Tremayne, Paul Polakis, Ron Firestein. An antibody drug conjugate (ADC) directed to lymphocyte antigen 6 complex, locus E (LY6E) delivers targeted chemotherapy to a wide range of solid tumor malignancies. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 947. doi:10.1158/1538-7445.AM2015-947
Abstract 965: Identification of KJ-Pyr-9 as a potent MYC inhibitor
Authors: Hart Jonathan R. , Bister Klaus , Janda Kim D. , Vogt Peter K.
Published: August 2015

We have identified a novel small-molecule inhibitor of MYC, KJ-Pyr-9, from a Kröhnke pyridine library. KJ-Pyr-9 functions as an inhibitor of MYC in biochemical assays, in cells and in xenograft experiments. In vitro, KJ-Pyr-9 binds to MYC as well as MYC-MAX dimers and can disrupt binding of MYC-MAX dimers with E-box DNA. In cells, MYC-MAX dimerization can be disrupted in cells as demonstrated by protein fragment complementation assays. KJ-PYR-9 disrupts the transcriptional targets of MYC. The P493-6 cell line has tetracycline regulatable MYC expression. For this cell line, the transcriptional targets of MYC can be readily observed upon the addition of 0.1 ug/mL doxycycline. Both doxycycline and KJ-PYR-9 negatively regulate MYC transcriptional signatures as determined by GSEA. The growth of a variety of different MYC-dependent cell lines are inhibited, including MYC translocated Burkitt's lymphoma cell lines expressing high levels of MYC as well as solid tumor cell lines expressing moderate amounts of MYC. In vivo, KJ-Pyr-9 effectively blocks the growth of a xenotransplant of MYC-amplified human cancer cells.

Citation Format: Jonathan R. Hart, Klaus Bister, Kim D. Janda, Peter K. Vogt. Identification of KJ-Pyr-9 as a potent MYC inhibitor. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 965. doi:10.1158/1538-7445.AM2015-965
Abstract 975: Monoclonal antibody targeting of ADAM17 is an effective treatment for metastatic colorectal cancer resulting in tumor growth control and reductions of cancer stem cells
Authors: Dosch Joseph , Ziemke Elizabeth , Welling Theodore , Hardiman Karin , Sebolt-Leopold Juidth , Michelotti Emil , Hollingsworth Robert , Hurt Elaine
Published: August 2015

ADAM17/TACE (TNFα converting enzyme) has been implicated to play a role in the drug resistance of colorectal cancers. The present study addresses the hypothesis that MEDI3622, a specific ADAM17 monoclonal antibody known to possess both human and mouse cross reactivity, represents a viable therapeutic strategy to improve outcome in the treatment of metastatic colorectal cancer (mCRC). We have generated both in vitro and in vivo data in patient-derived CRC models to provide compelling support for further exploration of this treatment strategy. A heterogeneous panel of low passage colorectal patient-derived xenografts (PDX) has been established from biospecimens procured during patient surgeries conducted at University of Michigan. All xenograft models have been genomically profiled and their histologies mimicked those observed in the original samples. As anticipated, approximately half of these models harbor an oncogenic KRAS mutation and exhibit widely differing histologies, consistent with the heterogeneity encountered in the clinic. Efficacy testing of MEDI3622 has shown that this agent significantly impaired tumor growth in 3 of the 5 PDX models examined, including one model that is KRASMT. Furthermore, cancer stem cell function in these CRC models is negatively impacted by MEDI3622, reducing tumor initiation frequencies in tumor re-implantation studies at the conclusion of treatment. Therefore our results suggest that a monoclonal antibody approach that targets ADAM17 may provide an attractive therapeutic strategy for the treatment of metastatic colorectal cancer both by reducing tumor growth and inhibiting cancer stem cells.

Citation Format: Joseph Dosch, Elizabeth Ziemke, Theodore Welling, Karin Hardiman, Juidth Sebolt-Leopold, Emil Michelotti, Robert Hollingsworth, Elaine Hurt. Monoclonal antibody targeting of ADAM17 is an effective treatment for metastatic colorectal cancer resulting in tumor growth control and reductions of cancer stem cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 975. doi:10.1158/1538-7445.AM2015-975
Abstract 99: Identification of G9a inhibitors by AlphaLisa™ technology and hit confirmation using MT-Glo™
Authors: Fromond Claudia , Espanel Xavier , Chene Laurent , Masson Philippe , Boubia Benaïssa , Montalbetti Christian , Broqua Pierre
Published: August 2015

Epigenetic processes control gene expression and play a major role in cell proliferation, survival and differentiation. Dysregulation of epigenetic mechanisms may lead to alterations in gene expression, resulting in cellular transformation and malignant outgrowth. Epigenetic enzymes are recognized as promising therapeutic targets for the treatment of cancer. Inventiva has several research programs in epigenetics, with specific focus on histone lysine methyltransferases (HKMTs). Emerging evidence suggests that G9a, a HKMT, able to mono and dimethylate H3K9 leading to the inactivation of tumor suppressor genes, plays a predominant role in lung and ovarian cancers. To identify novel G9a inhibitors, we used an AlphaLisa assay, with a histone H3-derived peptide and a specific antibody against H3K9me2. The assay, in 384-well format, displayed a robust Z-factor (0.84) with a signal to noise ratio around 800. We screened Inventiva's proprietary compound library using this assay. Three hundred thirty-six hits inhibited G9a by more than 60% (Hit rate: 0.14%). Despite the advantages offered by AlphaLisa technology, such as high S/N ratios and straightforward automation, this technology has been reported to generate a high number of false positives. In order to confirm the activity of our hits, we used a different technology, the methyltransferase Glo (MT-Glo) assay, which measures the reaction product SAH by luminescence read-out. Out of the 336 identified compounds, 75 were confirmed by this orthogonal screening (Hit confirmation rate: 22%). Additional compound characterization is ongoing to allow the selection of the best hit series for chemical optimization.

In conclusion, the AlphaLisa assay, coupled with MT-Glo assay allowed the identification and confirmation of potent hits against G9a, as chemical starting points for our hit-to-lead optimization program.

Citation Format: Claudia Fromond, Xavier Espanel, Laurent Chene, Philippe Masson, Benaïssa Boubia, Christian Montalbetti, Pierre Broqua. Identification of G9a inhibitors by AlphaLisa™ technology and hit confirmation using MT-Glo™. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 99. doi:10.1158/1538-7445.AM2015-99
Abstract CT119: Early results from a phase II study of RRx-001, a novel, triple epigenetic inhibitor, showing resensitization to irinotecan in colorectal cancer
Authors: Reid Tony , Fisher George , Carter Corey , Cho-Phan Cheryl , Kunz Pamela , Oronsky Bryan , Fanger Gary R. , Caroen Scott , Parker Christopher , Scicinski Jan
Published: August 2015

Background: Resistance acquisition to standard therapy in advanced colon cancer leads to poor patient survival. Epigenetic therapies can potentially reverse the chemoresistant phenotype. RRx-001, a novel ROS-mediated epigenetic modifier may resensitize to irinotecan-based therapies and increase overall survival compared to standard third-line regorafenib.

Methods: The phase II ROCKET study evaluates a sequential rechallenge to irinotecan-based therapies after RRx-001 or regorafenib. Patients with an ECOG PS 0-1 with irinotecan-refractory metastatic colorectal cancer who progressed on oxaliplatin-, and irinotecan-based regimens with or without bevacizumab, cetuximab or panitumumab are randomized 2:1 to receive RRx-001 16.5 mg/m2 IV 1x/week or regorafenib 160 mg orally 21 of 28 days until progression or unacceptable toxicity followed by treatment with refractory irinotecan-based therapies. The primary end point is overall survival with secondary endpoints to investigate resensitization. The study is planned to accrue approx. 190 patients and recruitment is ongoing.

Study Status and Results: To date, 23 patients have been randomized with 10 patients evaluable for resensitization. Post RRx-001 patients demonstrated marked decreases in CEA in all 6 patients as compared to 4 patients receiving regorafenib who were too systemically unwell to proceed to subsequent treatment.

Conclusions: Early results in this study suggest that resensitization to irinotecan-based therapies mediated by RRx-001, a systemically non-toxic novel epigenetic inhibitor, may be a general effect. These early results are intriguing and may predict for increased overall survival, adding an additional regimen after disease progression. The trial is continuing.

Citation Format: Tony Reid, George Fisher, Corey Carter, Cheryl Cho-Phan, Pamela Kunz, Bryan Oronsky, Gary R. Fanger, Scott Caroen, Christopher Parker, Jan Scicinski. Early results from a phase II study of RRx-001, a novel, triple epigenetic inhibitor, showing resensitization to irinotecan in colorectal cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr CT119. doi:10.1158/1538-7445.AM2015-CT119
Abstract CT130: Intravenous chemotherapy plus intraperitoneal perfusion chemotherapy for gastric cancer: A systematic review and meta-analysis
Authors: Yang Sheng , Feng Rui , Pan Zhangchi , Jiang Tao , Xu Qian , Chen Qiang
Published: August 2015

Purpose: This a review of randomized controlled trials (RCTs) of intravenous (IV) with or without intraperitoneal (IP) chemotherapy in patients with gastric cancer to determine the impact on effect and safety.

Methods: Databases, including Medline, Embase, Web of Science, the Cochrane Central Register of Controlled Trials (CENTRAL), ClinicalTrials.gov, Current Controlled Trials, and CINAHL were electronically searched for RCTs up to June 2013, and relevant references of the included articles were also manually searched. Two authors independently searched articles, extracted data, and assessed the quality of included studies. Meta-analyses were performed on the included data, for the outcomes survival rate, metastasis rate and adverse events. The Grading of Recommendations Assessment, Development and Evaluation System was used to rate the level of evidence.

Results: Five RCTs involving 1072 patients were included. Overall, a significant improvement in overall survival rate [relative risk (RR) = 1.21, 95% confidence interval (95% CI) 1.13 to 1.29, P<0.01], one-year survival rate (RR = 1.10, 95% CI 1.04 to1.17, P = 0.005), three-year survival rate (RR = 1.22, 95% CI 1.11 to1.35, P = 0.001), and five-year survival rate (RR = 1.42, 95% CI 1.12 to 1.80, P = 0.004) were associated with IV plus IP chemotherapy. Meta-analysis demonstrated that metastasis rate can be effectively decreased (RR = 0.35, 95% CI 0.25 to 0.50, P<0.01) but incidence of adverse events were increased using IV plus IP chemotherapy.

Conclusion: IV plus IP chemotherapy in patients with gastric cancer is associated with improved overall survival and prevented distant or peritoneal metastasis. However, increased risk of neutropenia, peripheral edema and neuropathy are also demonstrated.

Citation Format: Sheng Yang, Rui Feng, Zhangchi Pan, Tao Jiang, Qian Xu, Qiang Chen. Intravenous chemotherapy plus intraperitoneal perfusion chemotherapy for gastric cancer: A systematic review and meta-analysis. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr CT130. doi:10.1158/1538-7445.AM2015-CT130
Abstract CT306: Radiolabeled anti-PSMA antibody J591 immunotherapy is associated with favorable circulating tumor cell (CTC) count control in men with castration-resistant prostate cancer
Authors: Date Pravin , Karir Beerinder S. , Batra Jaspreet S. , Jhanwar Yuliya , Beltran Himisha , Nanus David M. , Bander Neil H. , Tagawa Scott T.
Published: August 2015

Background: J591 is a monoclonal antibody that selectively binds to prostate-specific membrane antigen (PSMA). Prospective phase I and II trials with therapeutic radiolabeled 177Lu-J591 have shown favorable PSA decline rates. Additionally, our group has previously reported that non-invasive evaluation of PSMA expression by imaging with planar gamma camera imaging is associated with response and survival. Initial anecdotal experience showed declines in CTC counts which led to prospective study.

Methods: Three clinical trials of 177Lu-J591 in men with metastatic CRPC have included prospective evaluation of CTC counts (CellSearch methodology) prior to and following therapy (single-dose 177Lu-J591, fractionated-dose 177Lu-J591, and fractionated-dose 177Lu-J591 + docetaxel). Based upon prior experience of J591-based therapy without an effector molecule as immunotherapy, and an anecdotal report of CTC count decline following a low (imaging) dose of J591 without an effector molecule, a cohort of patients who received J591 without 177Lu labeling was also retrospectively analyzed.

Results: 44 pts unselected for PSMA expression received 177Lu-J591 therapy had prospectively measured CTC counts. 39 of 44 pts (88.6%) had imaging evidence of PSMA expression. 57% of pts had baseline unfavorable (≥ 5 cells/7.5 mL) CTC counts. Of overall evaluable pts, 72.4% had decline in CTC counts (7.5 to 100% decline), with 50% of those with unfavorable baseline counts converting to favorable counts at 4-6 weeks. 17.1% with undetectable CTC counts remained undetectable at follow up. 7 pts with mCRPC and elevated CTC counts who received low-dose (naked J591) prior to imaging were also identified, and 4 (57%) of these pts demonstrated CTC count decline.

Conclusion: In addition to previously reported PSA declines, treatment with 177Lu-J591 is associated with favorable CTC count decline in men with metastatic CRPC. Infusion with unlabeled J591 may also lead to CTC count clearance. Based on this finding, we are planning a prospective clinical trial with unlabeled (naked) J591 in men with metastatic CRPC and unfavorable CTC counts.

Citation Format: Pravin Date, Beerinder S. Karir, Jaspreet S. Batra, Yuliya Jhanwar, Himisha Beltran, David M. Nanus, Neil H. Bander, Scott T. Tagawa. Radiolabeled anti-PSMA antibody J591 immunotherapy is associated with favorable circulating tumor cell (CTC) count control in men with castration-resistant prostate cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr CT306. doi:10.1158/1538-7445.AM2015-CT306
Abstract CT309: Rapid evaluation of a novel small molecule cMet tyrosine kinase inhibitor in healthy subjects
Authors: Millington A Dawn , Chaplan Sandra R. , Aguilar Zuleima , Fisher Dennis M. , Collier Jo , Mata Marielena , Mannens Geert , Goyvaerts Nico , Peddareddigari Vijay , Takimoto Chris
Published: August 2015

Inhibiting cMet has potential therapeutic value in oncology. The Janssen WAVE Early Development unit, a team focused on efficient proof-of-concept evaluations, sought to rapidly assess the safety, pharmacokinetics, and pharmacodynamics of a novel, highly selective small molecule cMet TK inhibitor with a favorable preclinical safety profile. We conducted a placebo-controlled, randomized, double blind single ascending dose and multiple dose trial in 84 healthy males at Quotient Clinical LTD (UK). The trial design was adaptive in several respects: to expedite determination of an optimal formulation and to maintain sufficient systemic exposure to sustain target inhibition. In the single ascending dose phase, doses ranged from 6-350 mg, with early transition from a solution to capsule formulation at 18 mg. Two multiple dose cohorts received 60 mg twice daily for 7 days (inter-dose intervals of 4.5 and 12 hours). Target engagement biomarkers were plasma hepatocyte growth factor and soluble cMet. Evaluation of renal safety was of particular interest.

Clinical evaluation, including both single ascending and multiple dose phases, was completed in only 6 months. All doses were safe and well tolerated. Pharmacokinetic analysis revealed dose-proportional increases in exposure. Dose escalation was limited by concentrations of a major metabolite that approached the ceiling established in preclinical toxicology studies. Renal toxicity was not identified.

Initial evaluation of this oncology drug in healthy subjects offered the advantages of rapid trial enrollment and completion, robust placebo comparison data, absence of concomitant illness or laboratory abnormalities, rapid dose escalation in a carefully-monitored, controlled setting, a thorough preliminary safety evaluation, and reduced costs. This approach, enabled by the acceptable preclinical safety profile of the compound, efficiently produced high quality clinical safety and pharmacokinetic data to support compound progression decisions.

Citation Format: A Dawn Millington, Sandra R. Chaplan, Zuleima Aguilar, Dennis M. Fisher, Jo Collier, Marielena Mata, Geert Mannens, Nico Goyvaerts, Vijay Peddareddigari, Chris Takimoto. Rapid evaluation of a novel small molecule cMet tyrosine kinase inhibitor in healthy subjects. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr CT309. doi:10.1158/1538-7445.AM2015-CT309
Abstract CT313: Phase Ib trial of dodecafluoropentane as a radiation sensitizer during chemoradiation for glioblastoma
Authors: Lickliter Jason , Ruben Jeremy , Longacre Olivia , Wilson David , Unger Evan
Published: August 2015

Purpose: Using post-resected glioblastoma multiforme (GMB) patients to evaluate the pharmacokinetics, safety and potential survival benefit of Dodecafluoropentane emulsion (DDFPe) in combination with the current standard of care; radiation therapy (RT) and temozolomide (TMZ). Glioblastoma multiforme (GBM) is known to be a hypoxic tumor. Tumor hypoxia limits response to RT. DDFPe is an oxygen therapeutic (OT) which transports more than 100x more oxygen as other tested fluorocarbons OT’s. Studies in tumor xenografts show that DDFPe increases tumor pO2 by up to 400% and mitigates radiation resistance.

Methods: Previously untreated GBM patients with post-resected residual tumor visible on MRI post surgery were enrolled. Patients received standard RT (60 Gray in 30 fractions over 6 weeks) with concurrent and adjuvant TMZ. In addition, DDFPe was infused intravenously over 30 minutes immediately prior to each fraction of RT while patients simultaneously breathed carbogen (98%O2:2% CO2). DDFPe was dosed using an accelerated titration design with 1 patient per dose level. Blood samples were drawn to evaluate DDFP pharmacokinetics. Objective tumor responses were assessed with gadolinium-enhanced MRI scans and RANO criteria, and tissue oxygen level dependent (TOLD) MRI was employed as an exploratory biomarker of tumor oxygenation.

Results: Two patients have been enrolled to date. The first patient received DDFPe at 0.05 cc/kg and completed chemoradiation and 2 cycles of adjuvant TMZ with dose reduction or delay. Therapy was well tolerated except for transient grade 3 ALT elevation during recovery from chemoradiation. A post-radiation MRI scan showed stable disease. The second patient has completed a regimen of chemoradiation in combination with DDFPe at 0.1 cc/kg.

Conclusions: DDFPe administration prior to each radiation fraction during standard chemoradiation of GBM is feasible. Further dose escalation od DDFPe is planned to establish a maximum tolerated dose and recommended dose for an envisioned Phase IIb multi-center GBM trial of DDFPe in combination with the accepted standard of care.

Citation Format: Jason Lickliter, Jeremy Ruben, Olivia Longacre, David Wilson, Evan Unger. Phase Ib trial of dodecafluoropentane as a radiation sensitizer during chemoradiation for glioblastoma. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr CT313. doi:10.1158/1538-7445.AM2015-CT313
Abstract CT318: Evaluation of salivary transcriptome markers for early detection of squamous cell cancer in a prospective blinded trial
Authors: Gottehrer Neil , Martin Jack
Published: August 2015

Oral squamous cell cancer (OSCC) is often diagnosed in late stages. Informative biomarkers could play a key role in early diagnosis. Prior case-control studies identified discriminatory salivary mRNA markers for OSCC. The National Cancer Institute (NCI) recommends prospective-specimen-collection, retrospective-blinded-evaluation (PRoBE) design study for rigorous biomarker identification and validation.

A PRoBE design study enrolled 170 patients with lesions suspicious for OSCC. Saliva was collected before performing oral biopsy. Six mRNAs (IL1β, IL8, OAZ1, SAT1, S100P, and DUSP1) were measured by quantitative polymerase chain reaction (PCR) without knowledge of tissue diagnosis. A pre-specified multi-marker panel from prior NCI - Early Detection Research Network (EDRN) studies was evaluated in this new PRoBE dataset. Individual marker cycle thresholds (Ct) from PCR were also compared in cancer versus control and new discriminatory models were generated.

The EDRN model was validated based on pre-specified statistical analysis plan. Ct values of individual mRNAs reflect an approximately two to nearly fourfold increase in concentration in invasive OSCC (p<0.01 for all). A new model from this intended use population demonstrates a maximal sum of sensitivity and specificity of 153.5% with an area under the receiver operating characteristic (ROC) curve of 0.81.

The validation of six pre-specified individual salivary transcriptome markers of OSCC and a pre-specified multi-marker model in a new prospective population, support the robustness of these markers and the multi-marker methodology. New models generated in this intended use population have the potential to further enhance the decision process for early biopsy.

Trial ID: NCT01587573

Citation Format: Neil Gottehrer, Jack Martin. Evaluation of salivary transcriptome markers for early detection of squamous cell cancer in a prospective blinded trial. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr CT318. doi:10.1158/1538-7445.AM2015-CT318
Abstract LB-001: Development and evaluation of a fluorescent antibody-drug conjugate for molecular imaging and targeted therapy of pancreatic cancer
Authors: Knutson Steve , Raja Erum , Bomgarden Ryan , Nlend Marie , Chen Aoshuang , Kalyanasundaram Ramaswamy , Desai Surbhi
Published: August 2015

Developing new strategies to effectively diagnose and treat various types of cancer is paramount to increasing patient survival rates. Although chemotherapeutic small molecules are effective for some cancer types, they often have harmful side effects, resulting in significant damage to healthy tissue. Targeted therapy, where anti-cancer drugs are more precisely delivered to specific cells, has the potential to revolutionize chemotherapy, through increased localized effective doses with minimized systemic toxicity. Antibody-drug conjugates (ADCs) are one such class of targeted therapy biopharmaceuticals, employing the inherent specificity of antibodies as a targeting mechanism to yield a potent drug delivery system. In addition to being used as ADCs, antibody-conjugates are also commonly used as a highly effective tool for cancer typing and longitudinal treatment monitoring by immunohistochemistry staining or diagnostic imaging. However, antibody-conjugates used for tumor diagnosis and treatment are different molecules. Fluorescent dye labeling of therapeutic antibodies has been previously demonstrated for cancer imaging. However, therapeutic antibodies dual-labeled with both chemotherapeutic small molecules and fluorescent dyes has not been reported. Here, we demonstrate the development of a directly-labeled, fluorescent antibody-drug conjugate for simultaneous targeted drug delivery and in vivo molecular imaging of cancer. Our novel biopharmaceutical entity is a monoclonal antibody specific for a carcinoembryonic antigen (CEA) biomarker conjugated to an average of one molecule of paclitaxel and two molecules of a near-infrared fluorophore (DyLight 680-4xPEG). Preliminary data show that this fluorescent ADC selectively binds CEA positive cells and is cytotoxic using in vitro model systems. Ongoing studies using an in vivo mouse xenograft cancer model will demonstrate the utility of this fluorescent ADC as a new concurrent pancreatic cancer detection, monitoring and treatment technology.

Citation Format: Steve Knutson, Erum Raja, Ryan Bomgarden, Marie Nlend, Aoshuang Chen, Ramaswamy Kalyanasundaram, Surbhi Desai. Development and evaluation of a fluorescent antibody-drug conjugate for molecular imaging and targeted therapy of pancreatic cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr LB-001. doi:10.1158/1538-7445.AM2015-LB-001
Abstract LB-011: Arginine deprivation using ADI-PEG20 leads to regression of an ASS1-ve intracranial GBM tumor in mice and potentiates gamma irradiation of ASS1+ve GBM in vitro
Authors: Abaitua Fernando , Przystal Justyna , Hajitou Amin , Syed Nelofer
Published: August 2015

Patients with Gliobastoma Multiforme (GBM) have an extremely poor overall survival rate. Novel molecular targeted therapies have failed to provide further improvements in these rates and as such the standard of care for GBM patients remains unchanged, consisting of radical surgery followed by chemo and radiotherapy. In light of this, novel therapeutic approaches have to be tested in combination with current protocols for their efficacy. We have previously demonstrated the metabolic dependency of ∼30% of de novo GBM to extracellular arginine. Using ADI-PEG20 to deplete arginine, we showed a marked reduction in the proliferation of primary GBM explants that exhibited methylation in their ASS1 gene, the rate-limiting enzyme in the arginine biosynthetic pathway.

We have validated these findings in an animal model where we have demonstrated that ADI-PEG20 treatment induces a profound delay in the growth of ASS1-ve intracranial human GBM tumors in mice. In cell culture models, we show that ADI-PEG20 has comparable cell growth inhibition efficiencies as conventional chemotherapies namely temozolomide, lomustine and chloroquine. Moreover, these agents exhibited inhibitory effects on proliferation in hypoxic conditions (1% O2) representing activity in a more physiological environment. Importantly, combination with ADI-PEG20 did not reduce efficiency of these conventional drugs. Although no synergistic effects of ADI-PEG20 with these chemotherapeutic agents was observed, synergy was detected in combination with irradiation. Here, we showed the ADI-PEG20 radio-sensitized GBM cell lines to photon irradiation regardless of their ASS1 methylation status: In clonogenic assays, there was a 50% enhanced decrease in colony formation with pre-treatment of ADI-PEG20 and subsequent photon irradiation when compared to irradiation alone.

These results suggest arginine deprivation therapy as a novel therapeutic strategy for ASS1-ve GBM. Moreover, we show that when combined with irradiation, ADI-PEG20 can be used to treat GBM irrespective of their ASS1 status.

Citation Format: Fernando Abaitua, Justyna Przystal, Amin Hajitou, Nelofer Syed. Arginine deprivation using ADI-PEG20 leads to regression of an ASS1-ve intracranial GBM tumor in mice and potentiates gamma irradiation of ASS1+ve GBM in vitro. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr LB-011. doi:10.1158/1538-7445.AM2015-LB-011
Abstract LB-015: VAMP2-NRG1 fusion gene is a novel oncogenic driver of non-small cell lung adenocarcinoma
Authors: Jung Yeonjoo , Yong Seunghui , Kim Pora , Lee Hee-Young , Jung Yeonhwa , Keum Juhee , Kim Suyeon , Lee Sanghyuk , Kim Jhingook , Kim Jaesang
Published: August 2015

Neuregulin 1 (NRG1) has been discovered as the tail moiety of fusion genes with several distinct partner head genes in lung cancers. These fusion genes activate ERBB2/ERBB3 receptor-mediated cell signaling and thereby function as oncogenic drivers. We have carried out whole-transcriptome sequencing of 100 non-small cell lung carcinoma (NSCLC) tumors and isolated a novel fusion gene consisting of Vesicle-Associated Membrane Protein 2 (VAMP2) and NRG1. RT-PCR and genomic DNA analysis were used to demonstrate inter-chromosomal translocation. Immunoblotting and soft agar assays were used to examine stimulating activity of the fusion gene through ERBB2/ERBB3 signaling pathway. The most highly expressed splice variant of VAMP2-NRG1 fusion gene was shown to be membrane-bound and display EGF-like domain of NRG1 extracellularly. VAMP2-NRG1 promotes anchorage-independent colony formation of H1568 lung adenocarcinoma cells. Ectopic expression of the fusion gene stimulates phosphorylation of ERBB2 and ERBB3 as well as down-stream targets, AKT and ERK, confirming activation of the signaling pathway. VAMP2-NRG1 is a novel oncogenic fusion gene representing a new addition to the list of NRG1 fusion genes which together may form an important diagnostic and clinical category of lung adenocarcinoma cases.

Citation Format: Yeonjoo Jung, Seunghui Yong, Pora Kim, Hee-Young Lee, Yeonhwa Jung, Juhee Keum, Suyeon Kim, Sanghyuk Lee, Jhingook Kim, Jaesang Kim. VAMP2-NRG1 fusion gene is a novel oncogenic driver of non-small cell lung adenocarcinoma. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr LB-015. doi:10.1158/1538-7445.AM2015-LB-015
Abstract LB-024: Inhibition of bone morphogenetic protein (BMP) type I receptors in lung cancer cells activates the TGFβ signaling cascades which increases Id1 expression by TAK1
Authors: Langenfeld John E. , Langenfeld Elaine , Castle Monica
Published: August 2015

Bone morphogenetic protein (BMP) signaling increases Id1 expression while the transforming growth factor (TGF) signaling typically decreases Id1 expression. BMP antagonists decrease growth of cancer through the inhibition of Id1. Both the BMP and TGF signaling pathways activate TGF activated kinase1 (TAK1). TAK1 has been shown to phosphorylate and activate the BMP transcription factor Smad1/5. The purpose of this study was to understand the cross regulation between the BMP and TGFβ signaling pathways in lung cancer cell lines that occurs following the inhibition of BMP signaling. Antagonists targeting the BMP (DMH2, DMH1), TGFβ (SB-505124), and TAK1 ((5Z)-7-Oxozeaenol) signaling cascades were used to examine the cross regulation between these pathways.

Here, we show using siRNA and BMP antagonists targeting the type I receptors that upon inhibition of BMP signaling in lung cancer cells, the TGFβ signaling cascade is activated. SB-505124 alone increases Id1 expression in H1299 cells. However, when BMP signaling was inhibited, SB-505124 decreases Id1 expression, which is associated with a decrease expression in pTAK1. When BMP signaling is inhibited, the TGFβ constitutively active alk5 receptor activates TAK1 and increases Id1 expression, which is attenuated with (5Z)-7-Oxozeaenol. A BMP antagonist together with a TGFβ antagonist further enhanced growth suppression. This study reveals that TGFβ signaling can increase the expression of Id1 when BMP signaling is inhibited in lung cancer cells, which is mediated by TAK1. The data suggests that the inhibition of both the BMP and TGF signaling pathways enhances growth suppression of lung cancer cells that involves the downregulation of Id1.

Citation Format: John E. Langenfeld, Elaine Langenfeld, Monica Castle. Inhibition of bone morphogenetic protein (BMP) type I receptors in lung cancer cells activates the TGFβ signaling cascades which increases Id1 expression by TAK1. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr LB-024. doi:10.1158/1538-7445.AM2015-LB-024
Abstract LB-027: Inhibition of mammalian target of rapamycin by Torin2, an ATP-competitive inhibitor, induces growth inhibition in adult T cell leukemia
Authors: Watanabe Tatsuro , Aragane Naoko , Sueoka Eisaburo
Published: August 2015

Adult T cell leukemia (ATL) is one of the aggressive malignant lymphomas induced by the infection of human T-cell Lymphotropic virus-1. Advanced stages of ATL patients still have a poor prognosis and novel therapeutic approaches are needed. Since mammalian target of rapamycin (mTOR) is a key molecule in cell growth and survival in a number of hematological malignancies, we here focused on mTOR signaling pathway consisting from mTOR complex 1 (mTORC1) and mTOR complex 2 (mTORC2). It has been already reported that inhibition of mTOR with rapamycin, a classical mTOR inhibitor, or its derivatives induces growth inhibition in ATL cells, and we found that Torin2, a second generation ATP-competitive mTOR inhibitor, has more beneficial effects than rapamycin does. Although Torin2 showed weaker growth inhibitory effect against ATL cell lines than rapamycin did at low concentrations (< 10 nM), its effect exceeded at higher concentrations (> 10nM) in CCK-8 assay and Trypan blue staining assay. To understand differences of mechanism of action between Torin2 and rapamycin, we first studied apoptosis and cell cycle arrest of the ATL cell line stained with annexin-FITC; Although both Torin2 and rapamycin caused G1 cell cycle arrest, a small number of ATL cells died in apoptotic manner at higher concentration of Torin2 but not of rapamycin. It is important to note that inhibition of mTOR pathway with rapamycin induced feedback activation of Akt (phosphorylation of Akt at Ser471), down stream of mTORC2, at high concentrations (> 50 nM) but Torin2 inhibited phosphorylation of Akt dose-dependently. Based on these results, we think Torin2 inhibits mTORC1 and mTORC2 followed by G1 cell cycle arrest, however rapamycin inhibits only mTORC1 and it induces feedback activation of Akt at high concentration resulting in resistance to apoptotic cell death. Thus, inhibition of mTOR pathway with Torin2 is new potent therapeutic approach in the treatment of ATL.

Citation Format: Tatsuro Watanabe, Naoko Aragane, Eisaburo Sueoka. Inhibition of mammalian target of rapamycin by Torin2, an ATP-competitive inhibitor, induces growth inhibition in adult T cell leukemia. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr LB-027. doi:10.1158/1538-7445.AM2015-LB-027
Abstract LB-030: Hepatocellular carcinoma-derived exosomes promote motility of immortalized hepatocyte through transfer of oncogenic proteins and RNAs
Authors: Wong Nathalie , He Mian
Published: August 2015

Exosomes are increasingly recognized as important mediators of cell-cell communication in cancer progression through the horizontal transfer of RNAs and proteins to neighboring or distant cells. Hepatocellular carcinoma (HCC) is a highly malignant cancer, whose metastasis is largely influenced by the tumor microenvironment. The possible role of exosomes in the interactions between HCC tumor cell and its surrounding hepatic milieu are however largely unknown. In this study, we comprehensively characterized the exosomal RNA and proteome contents derived from three HCC cell lines (HKCI-C3, HKCI-8 and MHCC97L) and an immortalized hepatocyte line (MIHA) using Ion Torrent sequencing and mass spectrometry, respectively. RNA deep sequencing and proteomic analysis revealed exosomes derived from metastatic HCC cell lines carried a large number of pro-tumorigenic RNAs and proteins, such as MET proto-oncogene, S100 family members and the caveolins. Of interest, we found exosomes from motile HCC cell lines could significantly enhance the migratory and invasive abilities of non-motile MIHA cell. We further demonstrated that uptake of these shuttled molecules could trigger PI3K/AKT and MAPK signaling pathways in MIHA with increased secretion of active MMP-2 and MMP-9. Our study showed for the first time that HCC-derived exosomes could mobilize normal hepatocyte, which may have implication in facilitating the protrusive activity of HCC cells through liver parenchyma during the process of metastasis.

Citation Format: Nathalie Wong, Mian He. Hepatocellular carcinoma-derived exosomes promote motility of immortalized hepatocyte through transfer of oncogenic proteins and RNAs. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr LB-030. doi:10.1158/1538-7445.AM2015-LB-030
Abstract LB-031: Biochemical profiling of cancer-associated KRAS mutants: clues towards an understanding of differential clinical outcomes
Authors: Hunter John C. , Gurbani Deepak , Carrasco Martin , Manandhar Anuj , Gondi Sudershan , Westover Kenneth
Published: August 2015

As one of the first identified and most commonly activated oncogenes, V-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS) has been a focus of cancer research for many decades. Despite progress in our understanding of RAS biology, significant questions remain unanswered regarding observed differences in clinical outcomes between tumors harboring different KRAS mutations. In an attempt to understand these clinical differences we characterized the pertinent biochemical properties of the most commonly observed KRAS mutants including, nucleotide exchange rate, intrinsic and GTPase activating protein (GAP)-stimulated GTP hydrolysis rate and affinity for one of the enzyme's primary downstream effectors, Raf kinase. We additionally solved high resolution crystal structures of four of these mutants and attempt to explain the observed biochemical differences between the mutants in the context of these structures. Based on the individual biochemical properties of each KRAS mutant, we propose a classification scheme to predict the propensity of the various mutants to activate Raf-kinase and respond to therapies targeting this downstream signaling pathway.

Citation Format: John C. Hunter, Deepak Gurbani, Martin Carrasco, Anuj Manandhar, Sudershan Gondi, Kenneth Westover. Biochemical profiling of cancer-associated KRAS mutants: clues towards an understanding of differential clinical outcomes. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr LB-031. doi:10.1158/1538-7445.AM2015-LB-031
Abstract LB-032: Soluble E-cadherin as a microenvironmental factor that enhances tumor progression
Authors: Patil Pratima , Mason Robert W. , Ambrosio Julia D' , Rajasekaran Ayyappan K.
Published: August 2015

During malignant transformation of epithelial cells, their well-organized architecture is disrupted. A key event observed during epithelial cancer progression is down regulation of E-cadherin (E-cad), a central adherens junction protein that plays a crucial role in directing cell polarity, epithelial architecture and cell-cell adhesion. One mechanism by which tumor cells downregulate E-cad is by the proteolytic cleavage of its extracellular domain by proteases such as the matrix metalloproteinases (MMPs). This proteolytic cleavage results in the shedding of the E-cad ectodomain as an 80 kDa fragment known as soluble E-cadherin (sE-cad). Elevated levels of sE-cad are found in the serum and urine of cancer patients. In tumor cells physiological consequences include enhanced tumor cell migration and invasion, induction of MMP secretion, and increased cell signaling; all of which ultimately result in tumor progression. sE-cad also causes morphological changes in epithelial cells, including disruption of the adherens junction. However, the influence of elevated sE-cad levels on normal tissue architecture is not well understood. Specifically, the mechanism by which sE-cad in the tumor microenvironment interacts with cellular E-cad in normal epithelium is yet to be elucidated.

We used a three-dimensional (3D) cell-culture system to determine the effects of sE-cad on normal epithelial cyst morphology. In this study, we show that recombinant, purified sE-cad can induce lumen-filling in normal non-tumorigenic Madin-Darby canine kidney (MDCK) epithelial cysts. The acinar luminal filling and multiple lumen formation induced by purified sE-cad represent changes in epithelial tissue structure that are characteristic of premalignant lesions reported in human epithelial glandular tumors. We further demonstrate that co-culturing of tumor cells with epithelial MDCK cysts results in disruption of 3D epithelial architecture and filling up of the hollow lumen. Our results also show that tumor cell-induced lumen filling is trigged by sE-cad shedding, with a concomitant increase in MMP-9. Using an inhibitor of MMP-9, we provide evidence that MMP-9 is crucial for lumen filling. Together, these novel findings indicate that invasive carcinoma cells can induce structural alterations in adjacent normal epithelium, and that elevated sE-cad levels disrupt epithelial architecture and activate signaling pathways in normal epithelial cells.

Citation Format: Pratima Patil, Robert W. Mason, Julia D' Ambrosio, Ayyappan K. Rajasekaran. Soluble E-cadherin as a microenvironmental factor that enhances tumor progression. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr LB-032. doi:10.1158/1538-7445.AM2015-LB-032