bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 921: Novel clinical targets revealed by kinome reprogramming in mutant ESR1 metastatic breast cancer
Authors: Dustin Derek , Gu Guowei , Chan Doug , Beyer Amanda , Edwards David , Corona-Rodriguez Arnoldo , Ellis Matthew , Fuqua Suzanne
Published: August 2019

Background: Approximately half of women with estrogen receptor (ER)-positive breast cancer who undergo adjuvant endocrine therapy (ET) develop disease progression and metastasis. Studies have revealed that up to 40% of metastatic patients develop tumors bearing a mutation in ESR1. ESR1 mutant (ESR1m) tumors are associated with a more aggressive metastatic disease course. Studies have shown that cancers can undergo “kinome reprogramming” in response to therapy and acquired genetic alterations within the tumor. Thus, we hypothesize that expression of ESR1 mutations induces kinome reprogramming, which presents novel potential therapeutic targets to selectively treat ESR1m metastatic breast cancer.

Methods: We performed Kinobeads Precipitation (KiP) using broad specificity kinase inhibitors to capture and quantify by MS the level of active kinases in MCF-7 ESR1 wild-type and ESR1 Y537S mutant cells. We performed targeted siRNA screens and immunoblots to validate the hyperactivity of several of these kinases. Specific kinase inhibitors are being used to test their effects on proliferation and invasion in vitro, and in ex vivo organoid growth assays. Xenograft models are being used to evaluate the effects of the inhibitors on primary tumor growth and distant metastasis.

Results: Hyperactivation of 169 kinases in ESR1m cells was revealed by KiP analysis. Hyperactivation of several growth factor receptors, the PI3K/Akt/mTOR pathway, and the JAK/STAT pathway was demonstrated in Y537S mutant cells. We tested specific inhibitors of these pathways, and have shown that the mutant cells have reduced proliferation when these pathways are targeted. We developed organoid growth assays using primary and metastatic tumors from MCF-7 and T47D Y537S ESR1 xenograft tumors, and the Y537S ESR1 WHIM20 PDX model, and found that ET in combination with these selected targeted kinase inhibitors decreased the growth of organoids. We are currently testing inhibitors in combination with ET in vivo, and preliminary results demonstrate a significant inhibition of distant metastatic frequency. These results suggest that selective inhibition of hyperactivated “reprogrammed” kinase pathways can restore ET sensitivity in ESR1m tumors, and may show promise for use in ER-positive metastatic breast cancer patients.

Citation Format: Derek Dustin, Guowei Gu, Doug Chan, Amanda Beyer, David Edwards, Arnoldo Corona-Rodriguez, Matthew Ellis, Suzanne Fuqua. Novel clinical targets revealed by kinome reprogramming in mutant ESR1 metastatic breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 921.
Abstract 922: Preclinical anticancer activity of LSZ102, a novel oral selective estrogen receptor degrader targeting wild-type and mutant ER
Authors: Gaither L. Alex , Yip Choi Lai Tiong , Wang Chunrong , Toy Weiyi , Sheng Qing , Chen Jinyun , Mishina Yuji , Das Rita , Peukert Stefan , Loo Alice , Chandarlapaty Sarat , Crystal Adam , Abrams Tinya J.
Published: August 2019

Estrogen receptor (ER) blockade is a well-established therapeutic approach in ER+ breast cancer. A novel oral selective estrogen receptor degrader (SERD), LSZ102, is in development. LSZ102 induces proteasome-mediated degradation of both wild type and mutant ERα in MCF-7 cells. LSZ102 also inhibits transcription of ERα target genes and results in a decrease in cell proliferation in a dose dependent manner. Expression of ERα Y537S results in a shift in inhibition of cell proliferation upon incubation with either LSZ102 or fulvestrant; however, the shift with LSZ102 was less severe. Similarly, LSZ102 induced a more pronounced level of ERα degradation than fulvestrant in the Y537S mutant MCF7 cells. Overall, LSZ102 is effective in the wild type and Y537S ERα mutant setting in vitro. In vivo, LSZ102 treatment of ER+ breast cancer xenografts resulted in inhibition of ERα regulated transcripts and a decrease in ERα protein levels. In the MCF7 xenograft model, expression of ERα Y537S resulted in reduced activity by fulvestrant, but not by LSZ102. In vivo, LSZ102 exhibited single agent and combination efficacy upon co-administration with the CDK4/6 inhibitor ribociclib and the alpha-specific PI3K inhibitor alpelisib. LSZ102 is currently in a Phase I clinical trial in patients with ER+ breast cancer in which it is tested as a single agent, and in combination with either ribociclib or alpelisib.

Citation Format: L. Alex Gaither, Choi Lai Tiong Yip, Chunrong Wang, Weiyi Toy, Qing Sheng, Jinyun Chen, Yuji Mishina, Rita Das, Stefan Peukert, Alice Loo, Sarat Chandarlapaty, Adam Crystal, Tinya J. Abrams. Preclinical anticancer activity of LSZ102, a novel oral selective estrogen receptor degrader targeting wild-type and mutant ER [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 922.
Abstract 930: On-target resistance to mutant selective EGFR inhibitors develops in an allele-specific manner dependent on the original EGFR activating mutation
Authors: Zhang Yunkai , Brown Benjamin P. , Westover David , Yan Yingjun , Qiao Huan , Huang Vincent , Du Zhenfang , Smith Jarrod A. , Ross Jeffrey S. , Miller Vincent A. , Ali Siraj , Bazhenova Lyudmila , Schrock Alexa B. , Meiler Jens , Lovly Christine M.
Published: August 2019

In-frame deletions within exon 19 (Ex19Del) and the Leu858Arg mutation within exon 21 (L858R) are the two most common oncogenic EGFR mutations found in non-small cell lung cancer (NSCLC). Currently, there is little data differentiating Ex19Del from L858R, and patients whose tumors harbor Ex19Del and L858R are approached similar in clinic when choosing EGFR tyrosine kinase inhibitors (TKIs). Unfortunately, resistance mutations may emerge against all classes of EGFR TKIs, including osimertinib. Recently, G724S has been identified as a novel mutation which is selected in osimertinib resistant tumors. Interestingly, in a large genomic profile database of NSCLC patient samples we found that G724S co-occurs preferentially with Ex19Del (15/19 G724S cases) but not with L858R (0/19 G724S cases). We further combined in silico and in vitro investigations to demonstrate the mechanism of G724S mutation confers resistance to TKIs in an oncogenic variant-dependent manner. Our in silico investigations showed evidence of reduced stability of the osimertinib-bound G724S/Ex19Del complex but not the osimertinib-bound G724S/L858R complex. G724S/Ex19Del-transduced cells are resistant to osimertinib treatment in vitro, while G724S/L858R-transduced cells are sensitive to osimertinib treatment. These results suggest G724S/Ex19Del may emerge under selective pressure from EGFR TKIs, and the underlying oncogenic profile of EGFR can influence the development of drug resistance mutations. Our results have potential direct implications for the treatment of patients with EGFR-mutant NSCLC.

Citation Format: Yunkai Zhang, Benjamin P. Brown, David Westover, Yingjun Yan, Huan Qiao, Vincent Huang, Zhenfang Du, Jarrod A. Smith, Jeffrey S. Ross, Vincent A. Miller, Siraj Ali, Lyudmila Bazhenova, Alexa B. Schrock, Jens Meiler, Christine M. Lovly. On-target resistance to mutant selective EGFR inhibitors develops in an allele-specific manner dependent on the original EGFR activating mutation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 930.
Abstract 946: Early signs of activity of Tedopi OSE2101, a multiple neoepitope vaccine, in a phase 3 trial in advanced lung cancer patients after failure to previous immune checkpoint inhibitors ATALANTE-1
Authors: Viteri Santiago , Vanel François-Roger , Hilgers Werner , Remon Jordi , Viteri-Ramirez Guillermo , Quoix Elisabeth
Published: August 2019

Introduction: Tedopi is a neoepitope vaccine restricted to HLA-A2 positive patients targeting five tumor-associated antigens frequently expressed in lung cancer cells. Potential enhanced efficacy of cancer vaccines after ICI treatment remains unexploited and its biological basis is poorly understood. The integrity of the antigen presentation pathway is crucial in vaccine activity and genetic alterations such as beta-2-microglobulin inactivating mutation may explain lack of efficacy. Tedopi is currently being tested in the phase III ATALANTE-1 trial compared with chemotherapy in advanced NSCLC patients (pts.) who relapse after ICI. We report early signs of safety and efficacy with Tedopi in the first step of the open-label study.

Methods: 18 pts have been enrolled in the experimental arm and received at least one dose of Tedopi. These pts have been assessed every 6 weeks for radiological response according to RECIST 1.1 criteria as well as toxicity according to CTCAE criteria. Tedopi dose was 5 mg injected subcutaneously every 3 weeks for 6 doses, then every 2 months completing 1 year of treatment and thereafter every 3 months until progression or toxicity. Description of three patients with significant clinical benefit with third-line treatment with Tedopi is presented.

Results: Patients’ clinical characteristics are reported in table 1. Treatment duration with Tedopi ranges from 4.9 to more than 12 months, including one patient with brain metastases. One patient achieved a partial response and two patients achieved stable disease by RECIST 1.1 criteria. Safety profile was manageable and no patient withdrawn for toxicity.

Conclusions: Tedopi after failure to previous ICI therapy as third-line treatment has shown long-term clinical benefit and good safety profile. Baseline genomic molecular profile assessment, as well as, immunophenotype searching evidence of vaccination are ongoing.

Citation Format: Santiago Viteri, François-Roger Vanel, Werner Hilgers, Jordi Remon, Guillermo Viteri-Ramirez, Elisabeth Quoix. Early signs of activity of Tedopi OSE2101, a multiple neoepitope vaccine, in a phase 3 trial in advanced lung cancer patients after failure to previous immune checkpoint inhibitors ATALANTE-1 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 946.
Abstract 976: Regulation of breast tumor metastasis by the dynamic interaction between the TMEM macrophage, tumor, and endothelial cells
Authors: Surve Chinmay R. , Harney Allison , Wang Yarong , Chen Xiaoming , Sharma Ved , Stanley Richard , Oktay Maja , Condeelis John
Published: August 2019

Tumor cell intravasation is an essential step in the metastatic cascade, but its exact mechanism is not completely understood. We have previously shown that the direct physical association of a tumor cell over-expressing Mena, a perivascular Tie2hi/Vegfhi macrophage and an endothelial cell, forming a cell triad termed “tumor microenvironment of metastasis” (TMEM), increases vascular permeability, facilitating intravasation of tumor cells. It is only at the TMEM site that intravasation occurs leading to breast tumor metastasis. TMEM density is a clinically validated prognostic marker of distant metastasis in breast cancer patients. The precise molecular mechanisms relating TMEM function had not been elucidated. Here we describe the molecular mechanism. We show here that TMEM function involves the three cells in TMEM: firstly endothelial cell-secreted Ang2 stimulates VEGF build up in the TMEM macrophage, secondly a tumor cell secretes CSF1 which, third, stimulates the TMEM macrophage VEGF secretion, leading to vascular opening and metastasis. In addition, we show that acute blockage of CSF1R and Tie2-Ang2 signaling by inhibitors and blocking antibodies both in vitro and in mammary tumors leads to decreased macrophage VEGF production and secretion, decreased trans-endothelial migration of tumor cells, and decreased TMEM-dependent vascular permeability, circulating tumor cells and lung metastases. We conclude that dynamic interaction between the cells associated with TMEM leads to Ang2 and CSF1-mediated stimulation of macrophage VEGF expression and secretion leading to vascular opening, resulting in tumor cell intravasation. This is the first description of the molecular mechanism behind the predictive power of the clinically used prognostic marker TMEM and represents a major step in defining new biomarkers and targets for the treatment of metastatic tumors.

Citation Format: Chinmay R. Surve, Allison Harney, Yarong Wang, Xiaoming Chen, Ved Sharma, Richard Stanley, Maja Oktay, John Condeelis. Regulation of breast tumor metastasis by the dynamic interaction between the TMEM macrophage, tumor, and endothelial cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 976.
Abstract 978: Tim-4+ tissue-resident macrophages impair antitumor T-cell immunity
Authors: Chow Andrew , Schad Sara , Sharma Sai K. , Budhu Sadna , Gupta Aditi , Pimentel Corrin , Zhong Hong , Lewis Jason S. , Poirier John T. , Wolchok Jedd D. , Rudin Charles M. , Merghoub Taha
Published: August 2019

Over 600,000 Americans and 8 million worldwide die of cancer each year. The success of immune checkpoint blockade with anti-PD-1 therapy has been a remarkable clinical advance. However, most patients do not respond to anti-PD-1 monotherapy and the majority of those who initially do respond eventually succumb to the disease. There is currently an unmet need to identify therapeutic strategies to overcome resistance and further enhance the efficacy of anti-PD-1 therapy. Tim-4 is a phosphatidylserine (PS) receptor that has been reported to be expressed on myeloid cells. Prior work has demonstrated that Tim-4 deficiency or blockade in mice is associated with features of autoimmunity and enhanced anti-tumor immunity. Using flow cytometry, immunohistochemistry, and in vivo biodistribution, we determined that Tim-4 is expressed predominantly on tissue-resident macrophages, such as Kupffer cells, peritoneal macrophages, pleural macrophages, and lymph node macrophages, but not tumor-associated macrophages, in mice and humans. We provide evidence that Tim-4+ macrophages produce high levels of the cytokines TNF-α and TGF-β, which have been linked to T cell dysfunction, and also the TGF-β activating integrin αv (CD51). Antibody blockade of Tim-4 enhances the anti-tumor activity of anti-PD-1 therapy after subcutaneous tumor inoculation of B16 melanoma, CT26 colon carcinoma, and MC38 colon carcinoma. Finally, combined blockade of Tim-4 and PD-1 resulted in substantially more curative responses in a MC38 model of peritoneal carcinomatosis, compared to anti-PD-1 monotherapy. This was associated with enhanced CD8+ T cell infiltration into the peritoneal cavity, increased CD8+ T cell/Foxp3+ regulatory T cell ratio, and reduced expression of the exhaustion marker PD-1. Thus, we show that Tim-4+ tissue-resident macrophages impair anti-tumor T cell immunity and antibody blockade of Tim-4 is a strategy that should be considered for clinical studies in cancers resistant to anti-PD-1 monotherapy.

Citation Format: Andrew Chow, Sara Schad, Sai K. Sharma, Sadna Budhu, Aditi Gupta, Corrin Pimentel, Hong Zhong, Jason S. Lewis, John T. Poirier, Jedd D. Wolchok, Charles M. Rudin, Taha Merghoub. Tim-4+ tissue-resident macrophages impair antitumor T-cell immunity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 978.
Abstract 983: Antibody-drug conjugates of NAMPT inhibitors: Discovery, optimization, and preclinical characterization
Authors: Neumann Chris , Olivas Kathleen C. , Wang Kung Pern , Waight Andrew B. , Meyer David W. , Loftus Luke V. , Zaval Margo C. , Anderson Martha E. , Jin Steven , Cochran Julia H. , Simmons Jessica K. , Pittman Paul G. , Li Fu , Ulrich Michelle L. , Wong Abbie , Zeng Weiping , Lyon Robert P. , Senter Peter D.
Published: August 2019

Nicotinamide phosphoribosyltransferase (NAMPT) regulates the biosynthesis of NAD from nicotinamide via a salvage biosynthetic pathway. Inhibition of NAMPT depletes cellular NAD levels leading to disruption of energy metabolism and cell death. Non-targeted small molecule NAMPT inhibitors have demonstrated poor tolerability in clinical trials and in preclinical models, including cardiac and retinal toxicities in rats. In an effort to improve the therapeutic window of this drug class, we pursued a targeted-delivery approach using antibody-drug conjugates. Through a medicinal chemistry effort, we identified novel NAMPT inhibitors that incorporate chemical functionality in the solvent-exposed terminus to allow construction of enzyme-cleavable drug linkers. Additionally, we applied a pyridinium-based linker strategy that allows for traceless linker attachment through a conserved nicotinamide-mimetic moiety of NAMPT inhibitors. Candidate molecules were evaluated for NAMPT binding affinity and cellular cytotoxicity as free drugs, and for cellular cytotoxicity as ADCs with the alternate linker strategies. Comparisons across inhibitors and linker strategies provide insight into optimal design of cleavable drug linkers for this class of drugs. In vitro, the ADCs deplete NAD and lead to downstream ATP depletion in a time-dependent manner. In vivo evaluation using human tumor xenografts shows translation of the pharmacodynamic effect resulting in tumor regression in models of Hodgkin lymphoma, non-Hodgkin lymphoma, and acute myeloid leukemia. Toxicology studies in Sprague Dawley rats demonstrate excellent tolerability at active doses, with no observable cardiac or retinal toxicities at the highest tested doses in single- and multi-dose regimens. These findings detail the development of a novel payload class and optimized linker strategy for use with antibody-drug conjugates, and demonstrate a preclinical efficacy and safety profile to support continued efforts toward clinical therapeutics.

Citation Format: Chris Neumann, Kathleen C. Olivas, Kung Pern Wang, Andrew B. Waight, David W. Meyer, Luke V. Loftus, Margo C. Zaval, Martha E. Anderson, Steven Jin, Julia H. Cochran, Jessica K. Simmons, Paul G. Pittman, Fu Li, Michelle L. Ulrich, Abbie Wong, Weiping Zeng, Robert P. Lyon, Peter D. Senter. Antibody-drug conjugates of NAMPT inhibitors: Discovery, optimization, and preclinical characterization [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 983.
Abstract 987: Glycoengineered MSCs for targeting platinum resistant ovarian tumors
Authors: Layek Buddhadev , Sehgal Drishti , Panyam Jayanth , Prabha Swayam
Published: August 2019

Tumor-targeted delivery of chemotherapeutics can improve efficacy while mitigating their debilitating side effects. However, current drug delivery approaches rely on inefficient passive accumulation of delivery systems in the tumor and suffer from significant non-specific distribution. Here, we propose a novel two-step tumor targeting strategy that can improve delivery of cytotoxic agents to both primary tumor as well as metastatic lesions, resulting in effective tumor inhibition. This strategy involves introduction of non-natural targets in the tumor tissue via glycoengineered mesenchymal stem cells (MSCs expressing targetable synthetic azide groups) followed by the delivery of drug-loaded polymeric nanoparticles (surface functionalized with dibenzyl cyclooctyne; DBCO) that have high affinity for these synthetic targets. DBCO surface functionalized, paclitaxel (PTX)-loaded nanoparticles (DBCO-PTX NP; 17.6% w/w PTX; diameter 313.7 ± 13 nm; and zeta potential -12.5 ± 1.9 mV) were formulated using poly (DL-lactide-co-glycolide) (PLGA) polymer by emulsion-solvent evaporation method. Glycoengineered MSCs (MSC-Az) were generated by culturing MSCs in N-azidoacetylmannosamine-tetraacylated supplemented media without affecting their viability or tumor homing properties. Binding of MSC-Az to DBCO-PTX NP was confirmed with confocal microscopy and flow cytometry analysis. Anticancer efficacy of two-step targeting strategy was evaluated in murine model of platinum-resistant orthotopic ovarian C200-luc tumors. Treatment with MSC-Az + DBCO-PTX nanoparticles resulted in significant inhibition of the tumor growth (p < 0.05) and improved survival (p < 0.05) compared to that with other controls. In summary, our results demonstrate the potential of two-step tumor targeting strategy to enhance the anticancer efficacy of conventional chemotherapeutic drugs.

Citation Format: Buddhadev Layek, Drishti Sehgal, Jayanth Panyam, Swayam Prabha. Glycoengineered MSCs for targeting platinum resistant ovarian tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 987.
Abstract 992: Comparative analyses of drug-loaded exosomal preparations from different cell types reveal distinctive loading capability, yield, and anti-tumor efficacies
Authors: KANCHANAPALLY RAJASHEKHAR , Deshmukh Sachin Kumar , Chavva Suhash Reddy , Tyagi Nikhil , Srivastava Sanjeev Kumar , Patel Girijesh Kumar , Singh Ajay P. , Singh Seema
Published: August 2019

Cancer remains one of the leading causes of death worldwide regardless of technological advancements. Inefficiency of current drug-delivery regimes is one of the important factors that limits the therapeutic efficacy of existing chemotherapeutics thus contributing to cancer mortality. To address this limitation, synthetic nanotechnology-based delivery systems have been developed; however, they raise concern of inducing adverse immunogenic reactions. Exosomes are non-immunogenic nano-sized vesicles that have received significant attention as efficient drug delivery system. Here we evaluated the efficacy of different cell types viz. pancreatic cancer cells (PCCs), pancreatic stellate cells (PSCs) and macrophages (MØs) for drug packaging and release into exosomes. PCCs shed the most exosomes and were the most efficient in drug loading followed by MØs and PSCs as examined by HPLC quantification. However, when compared for anti-tumor efficacy, MØs-derived exosomes-loaded with DOX (MØ-Exo-DOX) showed highest activity followed by PSCs and PCCs in WST-1 and Annexin V staining assays. These varying anti-tumor activities likely resulted from non-drug contents of exosomes since we did not observe any significant differences in their uptake by the cancer cells. Altogether, our data suggest that donor cell-specific differences exist in exosomes, which could influence their utility as drug carrier for therapeutic purposes.

Citation Format: RAJASHEKHAR KANCHANAPALLY, Sachin Kumar Deshmukh, Suhash Reddy Chavva, Nikhil Tyagi, Sanjeev Kumar Srivastava, Girijesh Kumar Patel, Ajay P. Singh, Seema Singh. Comparative analyses of drug-loaded exosomal preparations from different cell types reveal distinctive loading capability, yield, and anti-tumor efficacies [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 992.
Abstract CT045: Hyleukin-7, a long-acting interleukin-7, increased absolute lymphocyte counts after subcutaneous and intramuscular administration in healthy subjects
Authors: Lee Sang Won , Choi Donghoon , Heo MinKyu , Shin Eui-Cheol , Park Su-Hyung , Kim So Jeong , Lee Byung Ha , Yang Se Hwan , Sung Young Chul , Lee Howard
Published: August 2019

Higher lymphocyte counts predict lower mortality in patients with various oncologic malignancies. Interleukin-7 (IL-7), a homeostatic cytokine, plays a critical and non-redundant role in developing T-cells and maintaining immune functions after development. IL-7 is a potent T-cell amplifier, thereby contributing to immune reconstitution, which may result in clinical benefits. A randomized, double-blind, placebo-controlled, dose-escalation, Phase I study was conducted to assess the safety, tolerability, pharmacokinetic and biological properties of Hyleukin-7 (human IL-7 fused to hyFcTM) administered subcutaneously (SC) and intramuscularly (IM) to healthy volunteers.

Ten subjects randomly received Hyleukin-7 or its matching placebo in an 8:2 ratio in each of three cohorts at 20 and 60 μg/kg SC and 60 μg/kg IM. Dose escalation and switch from SC to IM was determined on 28 days after study drug administration based on the safety and tolerability data. Subjects were followed up to 56 days after dose.

Hyleukin-7 was well tolerated and no subject developed cytokine release syndrome. Injection site reactions were the most common treatment-emergent adverse events, which resolved spontaneously without treatment. Hyleukin-7 was slowly but steadily absorbed and its terminal half-life ranged 48-112 hours. Furthermore, Hyleukin-7 increased absolute lymphocyte counts (ALC) in a dose-dependent manner which lasted during the observed period of 56 days after dose. The mean maximum increase in ALC from baseline was seen 3 weeks after dose. IM Hyleukin-7 increased ALC greater than SC Hyleukin-7 did at the same dose (111.4% IM vs. 75.1% SC). In all of the doses, Hyleukin-7 markedly increased the numbers of all peripheral CD4+ and CD8+ lymphocyte subsets (i.e., naïve, EM, CM and TEMRA). These increases are attributed to enhanced expression of Ki-67.

SC and IM Hyleukin-7 was safe and well-tolerated in a dose range of 20 to 60 μg/kg in healthy subjects. A single SC and IM dose of Hyleukin-7 increased ALC dose-dependently. The results of this study warrant further investigation of Hyleukin-7 as a potential immune-oncology therapeutics to treat patients with compromised T-cell immunity.

Citation Format: Sang Won Lee, Donghoon Choi, MinKyu Heo, Eui-Cheol Shin, Su-Hyung Park, So Jeong Kim, Byung Ha Lee, Se Hwan Yang, Young Chul Sung, Howard Lee. Hyleukin-7, a long-acting interleukin-7, increased absolute lymphocyte counts after subcutaneous and intramuscular administration in healthy subjects [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr CT045.
Abstract CT052: A Phase Ib and II clinical trial investigating the efficacy of nitric oxide deprivation and docetaxel in triple negative breast cancer
Authors: Chung Andrew W. , Ensor Joe E. , Darcourt Jorge , Belcheva Anna , Patel Tejal , Chang Jenny C. , Niravath Polly A.
Published: August 2019

Triple negative breast cancer (TNBC) is an aggressive disease that currently lacks an efficacious form of therapy. Cancer relapse is thought to be initiated by chemotherapy-resistant breast cancer stem cells (BCSCs). Our previous studies revealed that BCSCs utilize inducible nitric oxide synthase (iNOS)-derived nitric oxide to promote their proliferation, migration, and self-renewal capacity. In an effort to target BCSCs, we found that iNOS inhibition with NG-monomethyl-L-arginine (L-NMMA) sensitized BCSCs to docetaxel in TNBC xenograft models, leading to decreased tumor burden. These findings suggest that BCSC resist conventional therapy in a nitric oxide-dependent manner and that combination of L-NMMA with docetaxel will effectively target BCSCs to prevent further relapse. A phase Ib/II clinical trial was conducted to determine the maximum tolerated dose, recommended phase 2 dose (R2PD), dose-limiting toxicities (DLTs), and efficacy of the L-NMMA and docetaxel combination in chemo-refractory Stage III and IV TNBC patients. For the phase Ib portion of the study, a standard Bayesian continual reassessment method is being used to investigate 7 dose levels of L-NMMA (5, 7.5, 10, 12.5, 15, 17.5, and 20 mg/kg) and two dose levels of docetaxel (75 and 100 mg/m2). Twenty patients have been recruited to date, and based on current pharmacokinetics, pharmacodynamics, and safety data, the RP2D is expected to be docetaxel 100 mg/m2 (Day 1) and L-NMMA 20 mg/kg (Days 1-5) every 3 weeks. At the RP2D, 87.5% of the patients experienced a decrease in total serum nitrates and nitrates at Day 2 (p = 0.0156, Wilcoxon Signed-Rank) as compared to baseline, and 75% experienced a decrease at Day 5 (p = 0.1484). Two and three patients received 15 mg/kg L-NMMA + 75 mg/m2 docetaxel and 17.5 mg/kg L-NMMA + 100 mg/m2 docetaxel, respectively. Of these 5 patients, one partial responder completed 8 cycles before discontinuing treatment due to taxane-associated neuropathy. Among the nine patients treated at the RP2D, only one taxane-associated DLT occurred. The overall response rate for patients treated at the higher doses was 33.3% as determined by RECIST 1.1. Early results of the phase Ib/II trial indicate the safety, tolerability, and promising activity of the first-in-class pan-NOS inhibitor L-NMMA in combination with chemotherapy in the treatment of chemo-refractory TNBC.

Citation Format: Andrew W. Chung, Joe E. Ensor, Jorge Darcourt, Anna Belcheva, Tejal Patel, Jenny C. Chang, Polly A. Niravath. A Phase Ib and II clinical trial investigating the efficacy of nitric oxide deprivation and docetaxel in triple negative breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr CT052.
Abstract CT149: A Phase II study of Genexol-PM and cisplatin as induction chemotherapy in locally advanced head and neck squamous cell carcinoma
Authors: Lee Keun-Wook , Keam Bhumsuk , Kim Jin-Soo , Lee Se-Hoon
Published: August 2019

Background Genexol-PM is a polymeric micellar formulation of paclitaxel without Cremophor EL. We investigated the efficacy and safety of Genexol-PM plus cisplatin as induction chemotherapy (IC) in patients with locally advanced head and neck squamous cell carcinoma (LA-HNSCC).

Methods Patients received Genexol-PM (230 mg/m2) and cisplatin (60 mg/m2) every 3 weeks as IC. After 3 cycles of IC, definitive treatment of either concurrent chemoradiotherapy (CCRT) with weekly cisplatin (30 mg/m2) or surgery was performed. The primary endpoint was objective response rate (ORR) after IC.

Results Of 52 patients enrolled, 47 completed three cycles of IC and the ORR was 55.8% (95% confidence interval, 42.3-69.3). Although there was one treatment-related death, toxicity profiles to IC were generally favorable and the most common grade 3 or 4 toxicities were neutropenia (15.4%), anorexia (7.7%) and general weakness (7.7%). Fifty one patients received the definitive treatment [CCRT (n=44) or radical surgery (n=7)]. The rate of complete response following CCRT was 81.8% (36/44). After a median follow-up of 39 months, estimates of progression-free survival and overall survival at 3 years were 54.3% and 71.3%, respectively.

Conclusions IC with Genexol-PM and cisplatin demonstrated modest tumor response with well-tolerated toxicity profiles for patients with LA-HNSCC.

Citation Format: Keun-Wook Lee, Bhumsuk Keam, Jin-Soo Kim, Se-Hoon Lee. A Phase II study of Genexol-PM and cisplatin as induction chemotherapy in locally advanced head and neck squamous cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr CT149.
Abstract DDT01-01: BI 905677: A first-in-class LRP5/6 antagonist targeting Wnt-driven proliferation and immune escape
Authors: Zinzalla Vittoria , Drobits-Handl Barbara , Savchenko Alexander , Rinnenthal Jörg , Bauer Markus Johann , Sanderson Michael , Blake Sophia Maria , Schweifer Norbert , Vries Robert Gerhardus Jacob , Clevers Hans , Kraut Norbert
Published: August 2019

Aberrant Wnt/β-catenin signalling has been shown to play a key role in tumorigenesis and resistance to immunotherapy in several tumor indications. Wnt ligand-mediated signals are transduced by two distinct receptor types, the serpentine receptor Frizzled (FZD) and the closely related single-span transmembrane proteins LRP5 and LRP6. Formation of the FZD-Wnt-LRP5/6 trimeric complex induces phosphorylation of LRP5 or LRP6 intracellular domains leading to inactivation of the β-catenin degradation complex, allowing stabilized β-catenin to enter the nucleus, bind to the TCF transcription factors, and act as a transcriptional activator of Wnt target genes. We have developed a first-in-class LRP5/6 antagonist, a bi-paratopic antibody comprising two modules binding to distinct epitopes of LRP5 (or LRP6). BI 905677 is a highly potent blocker of signalling induced by the Wnt family of ligands and shows anti-tumor activity in cancer models harbouring genomic alterations in upstream regulators of the Wnt pathway, such as RNF43 mutations or RSPO fusions. Furthermore, BI 905677 in combination with an anti-PD-1 immune checkpoint inhibitor induces dendritic cell activation and T cell infiltration in tumor tissues leading to complete responses in syngeneic tumor models. A Phase I clinical trial is underway in patients with advanced cancer to evaluate safety, tolerability, pharmacokinetic and pharmacodynamic properties, and efficacy of BI 905677 (NCT03604445).

Citation Format: Vittoria Zinzalla, Barbara Drobits-Handl, Alexander Savchenko, Jörg Rinnenthal, Markus Johann Bauer, Michael Sanderson, Sophia Maria Blake, Norbert Schweifer, Robert Gerhardus Jacob Vries, Hans Clevers, Norbert Kraut. BI 905677: A first-in-class LRP5/6 antagonist targeting Wnt-driven proliferation and immune escape [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr DDT01-01.
Abstract LB-005: Allosteric SHP2 phosphatase inhibition: Multiple mechanisms and chemotypes
Authors: LaMarche Matthew J. , Bagdanoff Jeff , Acker Mike , Chen Ying-Nan , Chan Homan , Dore Michael , Firestone Brant , Fodor Michelle , Garcia-Fortanet Jorge , Hentemann Murphy , Kato Mitsunori , Koenig Robert , Bonte Laura La , Liu Shumei , Mohseni Movarid , Ntaganda Rukundo , Sarver Patrick , Smith Troy , Sendzik Martin , Stams Travis , Spence Stan , Towler Chris , Wang Hongyun , Wang Ping , Williams Sarah , Chen Zhouliang , Hao Huaixiang , Liu Gang , Liu Chen , McNeill Eric , Yu Bing
Published: August 2019

Protein tyrosine phosphatase SHP2 is an oncoprotein associated with cancer as well as a potential immune modulator due to its role in the programmed cell death PD-L1/PD-1 pathway. Small molecule inhibition of SHP2 has been widely investigated including our previous reports describing SHP099, which binds to a tunnel-like allosteric binding site. To broaden our approach to allosteric inhibition of SHP2, we conducted additional hit finding, evaluation, and structure-based scaffold morphing. These studies led to the identification of multiple, potent inhibitor chemotypes, an additional and distinct allosteric binding site, and the identification of SHP394, an orally efficacious inhibitor of SHP2 with improved potency and enhanced pharmacokinetic properties. Overall, this work improves upon our previously described allosteric inhibitors, and exemplifies and extends the range of permissible chemical templates that inhibit SHP2 via the allosteric mechanism.

Citation Format: Matthew J. LaMarche, Jeff Bagdanoff, Mike Acker, Ying-Nan Chen, Homan Chan, Michael Dore, Brant Firestone, Michelle Fodor, Jorge Garcia-Fortanet, Murphy Hentemann, Mitsunori Kato, Robert Koenig, Laura La Bonte, Shumei Liu, Movarid Mohseni, Rukundo Ntaganda, Patrick Sarver, Troy Smith, Martin Sendzik, Travis Stams, Stan Spence, Chris Towler, Hongyun Wang, Ping Wang, Sarah Williams, Zhouliang Chen, Huaixiang Hao, Gang Liu, Chen Liu, Eric McNeill, Bing Yu. Allosteric SHP2 phosphatase inhibition: Multiple mechanisms and chemotypes [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr LB-005.
Abstract LB-030: Interferon signaling contributes to prostate cancer drug resistance
Authors: Agarwal Supreet , McGowen Kerry , Elloumi Fathi , Cam Maggie , Beshiri Mike , Corey Eva , Kelly Kathleen
Published: August 2019

Contrary to the anti-proliferative interferon (IFN) signaling, IFN related DNA damage resistance signature (IRDS) has pro-survival function and is responsible for cancer cell intrinsic therapy resistance. This signature encompasses a subset of STAT1-driven genes that have been associated with breast cancer therapy resistance. Interestingly, our RNAseq analysis of organoids from FACS-sorted Pten/Tp53-null PCa luminal progenitors have revealed a robust IRDS expression. Based on our previous findings that the luminal progenitors display intrinsic resistance to androgen deprivation therapy (ADT), we hypothesized that the IRDS expression might in part account for survival of PCa cells following ADT or genotoxic therapies. Our analysis of human PCa datasets revealed IRDS as a prognostic marker for progression in the TCGA primary PCa cohort (p<0.05). Further, high IRDS-expressing castrate resistance PCa (CRPC) patients in SU2C dataset were enriched for low AR signaling (r= -0.33, p< 0.05). Patients in IRDS-hi cohort showed enrichment for stem cell phenotype and for gene-sets associated with therapy resistance. In line with our analysis of clinical samples, real time PCR, immunofluorescence and western blot analysis of organoid cultures initiated from castration-resistant Pten/Tp53-nulltumor progenitors showed high levels of unphoshorylated STAT1 (U-STAT1) in tumor luminal organoids than WT organoids whereas pSTAT1 (Y701) was not detectable. Similarly, U-STAT1 was overexpressed in Pten/Tp53-null tumor relative to the WT tissue. Knockdown of STAT1 in tumor organoids decreased number of progeny organoids in subsequent generations suggesting either a direct or indirect effect upon self-renewal of luminal tumor stem cells. Altogether, U-STAT1 regulated signaling has pro-survival function in Pten/Tp53-null advanced PCa. Several PDXs originating from metastatic PCa express high levels of U-STAT1 dependent IFN signaling. STAT1 depletion in 5 tested PDXs significantly reduced self-renewing ability of PDX derived organoids, consistent with mouse luminal tumor organoids. Interestingly, STAT1 depletion synergized with sensitivity to chemotherapy ex vivo. These findings indicate that U-STAT1 dependent IFN signaling may contribute to treatment resistance. Overall, our findings suggest U-STAT1 dependent IRDS is correlated with poorly differentiated PCa and IRDS expression in part accounts for intrinsic therapy resistance in prostate cancer.

Citation Format: Supreet Agarwal, Kerry McGowen, Fathi Elloumi, Maggie Cam, Mike Beshiri, Eva Corey, Kathleen Kelly. Interferon signaling contributes to prostate cancer drug resistance [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr LB-030.
Abstract LB-032: NOG-FcgR KO hIL-15 Tg mice provide a highly sensitive assay system for ADCC activity of human NK cells
Authors: Katano Ikumi , Ito Ryoji , Kawai Kenji , Yagoto Mika , Suemizu Hiroshi , Ito Mamoru , Takahashi Takeshi
Published: August 2019

We have reported that a human interleukin (hIL)-15-gene introduced NOD-scidnullil2rgnull (NOG-hIL-15 Tg) mouse strain was useful for examination of in vivo antibody dependent-cellular cytotoxicity (ADCC) mediated by human NK cells in the presence of therapeutic Ab (Katano I et al. Sci. Rep. 2017). However, murine phagocytic cells including monocytes/macrophages (Mo/MΦ) in NOG mice still retain a significant capacity to kill target cells by antibody dependent-cellular phagocytosis (ADCP). Here, we newly generated a NOG-hIL-15 Tg strain deficient for Fcγ receptor genes (NOG-FcγR KO-hIL-15 Tg) and investigated whether ADCP by mouse Mo/MΦ could be abolished. The F4/80+ Mo/MΦ in NOG-FcγR KO mice did not bind human immunoglobulin, while those from NOG mice did. NOG-FcγR KO or NOG mice were intravenously transferred with a CD20+ human Burkitt’s lymphoma cell line, Daudi, followed by treatment with anti-hCD20 Ab, Rituximab (Rtx). The tumor growth in control NOG mice was significantly suppressed with Rtx-alone, whereas NOG-FcγR KO mice did not show tumor regression by Rtx treatment. After confirming engraftment of human NK cells in NOG-FcγR KO/hIL-15 Tg mice, we set up in vivo ADCC experiments. Daudi-transplanted NOG-FcγR KO/hIL-15 Tg mice were intravenously transferred with human NK cells and treated with Rtx. Only the mouse group with both human NK cells and Rtx treatment showed a significant suppression in the tumor growth.

These results suggest that NOG-FcγR KO mice are free of murine cell mediated ADCP, and that NOG-FcγR KO/hIL-15 Tg mice enable more specific detection of in vivo ADCC than NOG-hIL-15 Tg mice.

Citation Format: Ikumi Katano, Ryoji Ito, Kenji Kawai, Mika Yagoto, Hiroshi Suemizu, Mamoru Ito, Takeshi Takahashi. NOG-FcgR KO hIL-15 Tg mice provide a highly sensitive assay system for ADCC activity of human NK cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr LB-032.
Abstract LB-042: High ITGB1 & RhoC expressions are indicators of recurrence in patients with primary colorectal cancer
Authors: Ha Ye Jin , Tak Ka Hee , Kim Chan Wook , Lee Jong Ryul , Cho Dong-Hyung , Kim Yong Sung , Kim Seon-Kyu , Kim Jin Cheon
Published: August 2019

Colorectal cancer (CRC) is the main cause of cancer mortality worldwide. Its poor prognosis is mainly ascribed to high recurrence rates. Identifying novel prognostic biomarkers and therapeutic key points for management is crucial and important. To develop prognostic biomarkers that can discriminate CRC patients with high risk of postoperative recurrence, we conducted RNA-seq analysis using primary cancer tissues from 130 CRC patients with (n=58) or without (n=72) systemic recurrence. Among differentially expressed genes between with or without recurrence, we identified eleven candidate genes (AK2, BID, CDC25A, EIF4A2, HSPB1, ITGB1, MAP4K4, MMP12, PTGES3, RHOC, TERF21P) (P < 0.01). Then, the expression level of the best candidate gene was validated by quantitative real-time polymerase chain reaction (qRT-PCR) in the additional 79 CRC patients with (n=40) or without (n=39) systemic recurrence. Among these genes, qRT-PCR showed that AK2, EIF4A2, ITGB1 and RhoC were upregulated. To the relevance of their molecular function and biological process, Cell Counting Kit-8 assay, migration, invasion assay and gelatin zymograpy were performed after knockdown or overexpression of candidate genes in CRC cell lines. ITGB1 or RhoC stimulated colon cancer cell proliferation, promoted cell invasion and migration, whereas the opposite pattern was observed in ITGB1 or RhoC-overexpressing CRC cells. Western blotting experiments revealed that ITGB1 and RhoC overexpression downregulated E-cadherin and upregulated N-cadherin, Snail/Slug, Vimentin protein levels, whereas ITGB1 and RhoC knockdown had the opposite effects These results suggested that ITGB1 and RhoC promoted colon cancer cell proliferation, migration and invasion through EMT switch signaling pathway. Our results indicate that ITGB1 and RhoC may be biomarkers to predict recurrence and future therapeutic targets of CRC.

Citation Format: Ye Jin Ha, Ka Hee Tak, Chan Wook Kim, Jong Ryul Lee, Dong-Hyung Cho, Yong Sung Kim, Seon-Kyu Kim, Jin Cheon Kim. High ITGB1 & RhoC expressions are indicators of recurrence in patients with primary colorectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr LB-042.
Abstract LB-059: Hyperglycemia enhances cancer immune evasion by inducing alternative macrophage polarization through increased O-GlcNAcylation
Authors: Mantuano Natalia Rodrigues , Stanczak Michal , Oliveira Isadora , Filardy Alessandra , Silva Ronan , Zippelius Alfred , Todeschini Adriane Regina , Laubli Heinz
Published: August 2019

Epidemiological studies have shown diabetes mellitus (DM) to significantly increase the risk for cancer and cancer progression. Hyperglycemia is the most important characteristic of DM and directly correlates with a poor prognosis in cancer patients. While enhanced availability of glucose can directly fuel tumor cell proliferation, the effect on the tumor immune microenvironment is less well known. Here, we demonstrate in vitro and in different murine tumor models that hyperglycemia induces an increased flux through the hexosamine biosynthetic pathway (HBP) in tumor-associated macrophages (TAMs) resulting in an upregulation of O-GlcNAcylation. Increased O-GlcNAcylation was associated with alternative M2 polarization of TAMs and reduced anti-tumor immunity. The effect of hyperglycemia on tumor growth was dependent on an intact adaptive immunity. Furthermore, inhibition of M2 polarization by the addition of anti-CSF1R antibodies abrogated the effect of hyperglycemia on tumor growth. Similarly, treatment of mice with inhibitors of the HBP or O-GlcNAcylation reduced M2 polarization of TAMs and reversed immune evasion of growing tumors. Finally, we find enhanced M2 polarization in chronically hyperglycemic patients with colorectal cancer compared to non-diabetic normoglycemic patients. Our findings provide a new and targetable mechanism of cancer immune evasion, advocating for strict control of hyperglycemia in cancer patients.

Citation Format: Natalia Rodrigues Mantuano, Michal Stanczak, Isadora Oliveira, Alessandra Filardy, Ronan Silva, Alfred Zippelius, Adriane Regina Todeschini, Heinz Laubli. Hyperglycemia enhances cancer immune evasion by inducing alternative macrophage polarization through increased O-GlcNAcylation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr LB-059.