bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 4460: TET1 over expression contributes to lung cancer malignancy
Authors: Filipczak Piotr Teodor , Leng Shuguang , Tellez Carmen S. , Belinsky Steven A.
Published: July 2017

Epigenetic alterations are a leading cause of lung carcinogenesis and malignancy. While the role of enzymes catalyzing cytosine-guanine (CpG) island methylation and chromatin modifications has been extensively studied, the role of the recently discovered demethylating enzymes represented by ten-eleven translocation methylcytosine dioxygenases (TETs) remains unknown. The goal of this study was to investigate the expression and functional significance of the TET1 gene in non-small cell lung cancer (NSCLC). QRT-PCR revealed 2- to 30-fold over expression of TET1 in 52% of squamous cell carcinoma (SCC) and 40% of adenocarcinoma (AdC) tumors compared to paired normal lung tissue. This result was validated using The Cancer Genome Atlas (TCGA) database with TET1 over expressed in 72% of SCCs and 53% of AdCs. Elevated levels of TET1 transcript were associated with increased protein levels in NSCLC cell lines compared to normal human bronchial epithelial cells (HBECs). A reporter assay analysis defined the promoter region critical for elevated transcription of the TET1 gene using lung cancer cell lines, and studies to identify the transcription factors underlying the increase in expression are underway. Transient knock down of TET1 expression in NSCLC cell lines caused global changes in the transcriptome, reduced cell proliferation, colony formation, and inhibited growth of tumor xenografts in nude mice. Cellular senescence mediated by p21 signaling and associated with β-galactosidase activation was identified as one mechanism underlying growth inhibition. This study suggests that TET1 may function as an oncogene contributing to the lung cancer malignant phenotype and thus, could serve as a potential new target for treatment. (Supported by R01 CA183296)

Citation Format: Piotr Teodor Filipczak, Shuguang Leng, Carmen S. Tellez, Steven A. Belinsky. TET1 over expression contributes to lung cancer malignancy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4460. doi:10.1158/1538-7445.AM2017-4460
Abstract 4462: ACTN4 stabilises RIPK1 to function as an oncogenic driver in melanoma
Authors: Jin Lei , Tabatabaeehatambakhsh Hessam , Jiang Chen Chen , Yan Xu Guang , Wang Jia Yu , Zhang Yuan Yuan , Yari Hamed , Wang Chun Yan , La Ting , Lei Fu Xi , Feng Yu Chen , Guo Su Tang , Zhang Xu Dong
Published: July 2017

We have recently reported that receptor-interacting protein kinase 1 (RIPK1) is commonly up-regulated through cellular inhibitor apoptosis protein (cIAP)-mediated stabilization and functions as an oncogenic driver via activation of NF-κB in melanoma cells. Here we show that α-actinin-4 (ACTN4), an isoform of α-actinins of spectrin superfamily proteins that is emerging as an oncogenic regulator, is required for cIAP-mediated stabilization of RIPK1 and plays a pro-oncogenic role in melanoma. Similar to RIPK1, ACTN4 was found to be commonly increased in melanoma cells. While knockdown of ACTN4 inhibited melanoma cell proliferation that was associated with down-regulation of RIPK1 and reduction in the basal levels of NF-κB activation, overexpression of ACTN4 resulted in enhanced proliferation of melanocytes that was associated with elevation in RIPK1 expression and increased NF-κB activation. The inhibitory effect of ACTN4 knockdown on melanoma cell proliferation and activation of NF-κB was due to decreased expression of RIPK1, as it was abolished by overexpression of RIPK1. On the other hand, knockdown of RIPK1 diminished ACTN4 overexpression-triggered enhancement in proliferation in melanocytes. Strikingly, knockdown of ACTN4 attenuated the association between cIAPs and RIPK1 and reduced K63-linked ubiquitination of the protein, leading to RIPK1 protein degradation. Mechanistic studies showed that ACTN4 bound to RIPK1 through its N-terminus, whereas it was associated with cIAPs via its C-terminus, and that dimerization of ACTN4 in an anti-parallel manner is required for the interaction between cIAPs and RIPK1. Collectively, ACTN4 is necessary for stabilization of RIPK1 by cIAPs and functions as an oncogenic driver in melanoma.

Citation Format: Lei Jin, Hessam Tabatabaeehatambakhsh, Chen Chen Jiang, Xu Guang Yan, Jia Yu Wang, Yuan Yuan Zhang, Hamed Yari, Chun Yan Wang, Ting La, Fu Xi Lei, Yu Chen Feng, Su Tang Guo, Xu Dong Zhang. ACTN4 stabilises RIPK1 to function as an oncogenic driver in melanoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4462. doi:10.1158/1538-7445.AM2017-4462
Abstract 4467: ETV6 is a tumor suppressor regulated by EGFR-miR-96 pathway in prostate cancer
Authors: Liu Yen-Nien , Tsai Yuan-Chin , Chen Wei-Yu , Siu Man Kit , Yeh Hsiu-Lien
Published: July 2017

ETV6 is an ETS transcription factor and a putative tumor suppressor in prostate cancer according to several genomic analyses. However, its cellular functions and upstream regulating signaling remain unclear. We demonstrated that ETV6 suppresses the prostate cancer progression and that ETV6 levels are negatively associated with advanced prostate cancer, supporting the idea that ETV6 acts as a tumor suppressor. Furthermore, ETV6 can be regulated by epidermal growth factor receptor (EGFR) signaling through microRNA (miR)-mediated downregulation. One of the miRs, miR-96, can be transcriptionally-regulated by nuclear EGFR. The association patterns connecting miR-96, EGFR activation, and ETV6 were further validated in the clinical tissue samples. We proposed an EGFR-miR-96-ETV6 signaling pathway in promoting prostate cancer.

Note: This abstract was not presented at the meeting.

Citation Format: Yen-Nien Liu, Yuan-Chin Tsai, Wei-Yu Chen, Man Kit Siu, Hsiu-Lien Yeh. ETV6 is a tumor suppressor regulated by EGFR-miR-96 pathway in prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4467. doi:10.1158/1538-7445.AM2017-4467
Abstract 4490: Post-transcriptional regulation on PIAS3 expression in malignant mesothelioma
Authors: He Tian , McColl Karen , Sakre Nneha , Wildey Gary , Dowlati Afshin
Published: July 2017

Protein Inhibitor of Activated STAT3 (PIAS3) was originally identified as an endogenous suppressor of STAT3 activity which can specifically interact with activated STAT3 and block its downstream oncogenic effects. Previous studies from our lab have shown that low PIAS3 protein expression in mesothelioma tumors was associated with poor patient survival. Furthermore, low PIAS3 expression in mesothelioma cell lines correlated with higher STAT3 activity. Over-expression of PIAS3 decreased STAT3 activity and cell growth. These findings suggest that low PIAS3 expression may play an important role in mesothelioma tumorigenesis, thus understanding the regulatory mechanism(s) of PIAS3 expression may provide new therapeutic strategies in mesothelioma treatment. Initially, we examined PIAS3 expression by western blotting and RT-qPCR among six mesothelioma cell lines (H28, 211H, H2052, H2452, HAY, YOU) and found that while PIAS3 mRNA levels were relatively constant, PIAS3 protein expression was highly variable. This finding indicated a potential post-transcriptional regulation of PIAS3 expression in mesothelioma. To investigate this further, we first examined PIAS3 protein stability in the presence of proteasome inhibitors and cycloheximide (CHX). We observed no increase in PIAS3 protein levels during proteasome inhibition using either MG132 (10 μM) or bortezemib (1 μM) for up to 8 h in 211H, H2052 and H2452 cells, whereas TP53 protein expression was increased. Blocking translational protein synthesis with 50 or 100 μg/ml CHX for up to 24 h also produced little change in PIAS3 protein expression in mesothelioma cells, indicating that PIAS3 is a very stable protein. We next explored the PIAS3 3’UTR as a potential site for translational regulation. We initially utilized a miR microarray and computational analysis, followed by a PIAS3 3’UTR luciferase reporter assay, to screen miRNAs that are both increased in cells with low PIAS3 and have seed sequences targeting the PIAS3 3’UTR and identified miR-18a as our first candidate. Taken together, our study suggests that variable expression of PIAS3 protein in mesothelioma is regulated by translational control and not by protein stability.

Citation Format: Tian He, Karen McColl, Nneha Sakre, Gary Wildey, Afshin Dowlati. Post-transcriptional regulation on PIAS3 expression in malignant mesothelioma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4490. doi:10.1158/1538-7445.AM2017-4490
Abstract 4498: Targeting IRE1a-XBP1 signaling in lung cancer
Authors: Crowley Michael J. , Yomtoubian Shira , Markowitz Geoffrey , Altorki Nasser K. , Gao Dingcheng , Cubillos-Ruiz Juan , Mittal Vivek
Published: July 2017

Every year 1.5 million people die from lung cancer worldwide. Approximately ~15-30% of non small cell lung cancers (NSCLC) are driven by KRAS mutations and currently possess no viable therapeutic options. As such the discovery of effective therapeutic alternatives for the treatment of KRAS driven NSCLC are sorely needed. One prospect being explored in other solid tumors, but currently unexplored in NSCLC, is targeting the endoplasmic reticulum (ER) stress response. Adverse conditions in tumors such as hypoxia, nutrient starvation and reactive oxygen species disrupt protein folding, and induce ER stress. The most evolutionarily conserved pathway by which this insult is alleviated is the IRE1α-XBP1 axis, which responds by increasing the expression of a broad range of protein folding and quality control genes. Previous work has demonstrated that several cancers utilize this pathway to promote tumorigenesis, progression, epithelial to mesenchymal transition and metastasis. A preliminary analysis of a tissue microarray containing 304 human NSCLC samples, 254 demonstrated at least some positivity and >50% were strongly positive for the active isoform of XBP1. Given these preliminary findings we investigated the status of IRE1a-XB1 in our murine orthotopic model and confirmed the activation of IRE1a-XBP1 signaling in tumor cells in the context of the tumor microenvironment. Furthermore, in both cell types we can see the activation of canonical downstream targets of XBP1. Utilizing the CRISPR-CAS9 system, we knocked out IRE1a in the orthotopic tumor cell line. IRE1a abrogation was confirmed by western blot, evaluating the fraction of active XBP1 after induced ER stress in vitro, and qPCR of canonical downstream targets. Additionally, this knockout did not alter proliferation or morphology in vitro. However, when tumors were grown orthotopically, Cas9-IRE1a knockouts failed to grow past 10 days, whereas Cas9-Scramble controls and the parental tumor line grew comparably until end stage. Given these preliminary findings and data from prior studies, we hypothesize that the abnormal activation of the IRE1α-XBP1 axis may influence KRAS NSCLC progression and aggressiveness and serve as a potential novel avenue for the treatment of NSCLC. After probing the impact of the underlying mechanism on tumor growth we will finally evaluate the translational utility of targeting the ER stress pathway with a small molecule inhibitor against IRE1a.

Citation Format: Michael J. Crowley, Shira Yomtoubian, Geoffrey Markowitz, Nasser K. Altorki, Dingcheng Gao, Juan Cubillos-Ruiz, Vivek Mittal. Targeting IRE1a-XBP1 signaling in lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4498. doi:10.1158/1538-7445.AM2017-4498
Abstract 4519: ATM/ATR-SerRS pathway dominates hypoxic angiogenesis in tumor
Authors: Shi Yi , Liu Ze , Yang Xiang-Lei
Published: July 2017

Hypoxia-induced angiogenesis is a critical response in multicellular organisms to maintain oxygen homeostasis. It is also an important mechanism to support tumor progression. Hypoxia activates hypoxia-inducible factor (HIF) and HIF-independent pathways to transcriptionally induce the expression of pro-angiogenic genes. However, our knowledge on transcriptional repressors of angiogenesis and how they are regulated during hypoxia are limited. Here we report that seryl-tRNA synthetase (SerRS), a newly identified transcriptional repressor of vascular endothelial growth factor (VEGFA), is a major inhibitor of angiogenesis that is inactivated during hypoxia1-4. Inactivation of SerRS is achieved through its phosphorylation at serine 101 and serine 241 by ataxia telangiectasia mutated (ATM) and the related kinase ATR. Knockdown of HIF is not sufficient to completely block hypoxia-induced VEGFA expression in human cells unless a phosphorylation-deficient form of SerRS (SerRSS101A/S241A) is simultaneously expressed to escape ATM/ATR inactivation. Consistently, in mice, SerRSS101A/S241A can bypass hypoxia response despite HIF activation to strongly inhibit angiogenesis in a matrigel assay and a xenograft model of human breast cancer. These findings reveal ATM/ATR-SerRS pathway as a key negative regulator of angiogenesis related to hypoxia and a new target for cancer therapy.

References 1. Fukui, H., Hanaoka, R., and Kawahara, A. (2009). Noncanonical activity of seryl-tRNA synthetase is involved in vascular development. Circ Res 104, 1253-1259. 2. Herzog, W., Muller, K., Huisken, J., and Stainier, D. Y. (2009). Genetic evidence for a noncanonical function of seryl-tRNA synthetase in vascular development. Circ Res 104, 1260-1266. 3. Shi, Y., Xu, X., Zhang, Q., Fu, G., Mo, Z., Wang, G. S., Kishi, S., and Yang, X. L. (2014). tRNA synthetase counteracts c-Myc to develop functional vasculature. Elife 3, e02349. 4. Xu, X., Shi, Y., Zhang, H. M., Swindell, E. C., Marshall, A. G., Guo, M., Kishi, S., and Yang, X. L. (2012). Unique domain appended to vertebrate tRNA synthetase is essential for vascular development. Nat Commun 3, 681.

Citation Format: Yi Shi, Ze Liu, Xiang-Lei Yang. ATM/ATR-SerRS pathway dominates hypoxic angiogenesis in tumor [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4519. doi:10.1158/1538-7445.AM2017-4519
Abstract 4525: Hypoxia signaling pathway plays a role in ovarian cancer chemoresistance
Authors: Cutter Noelle L. , Walther Tyler , Doyle Kimberly H. , Frank Ryan
Published: July 2017

Hypoxia-inducible factor 1 (HIF-1) is a basic helix-loop-helix transcription factor that when induced regulates the expression of many genes involved in cytoprotective stimuli, which attenuates apoptosis and improves survival.. Increased expression of HIF-1α gene (HIF1A) has been found in several carcinomas, including ovarian cancer. Ovarian cancers are generally refractory to platinum-based chemotherapy. Despite the large number of studies, molecular events that govern the emergence of aggressive therapy-resistant cells after chemotherapy are poorly defined. Genomic instabilities, such as copy number variation(CNV), may play an important role in chemoresistance and have been implicated in many complex diseases, like cancer.. We analyzed CNV data that is publically available through the Cancer Genome Atlas and others. Of particular interest was the transcription factor HIF1A which plays an integral role in oxidative stress response such as those induced by chemotherapy reagents. The present study provides evidence for the rare escape of tumor cells from drug-induced cell death by entering a non-cycling senescent state. We report the adaptive response of human ovarian surface epithelium cells to CoCl2, a chemical hypoxia-mimicking agent resulting in a senescent-like state of chemoresistant cells. The effect of the treatment was evaluated on CNV of HIF-1α gene expression, cell proliferation, survival, and tumor invasiveness. We show here that CNV duplication events of HIF1α results in an oxidative stress response in cells leading to chemoresistance through the induction of cellular senescence. Understanding the molecular events associated with chemoresistance will ultimately lead to better patient treatment and outcomes.

Note: This abstract was not presented at the meeting.

Citation Format: Noelle L. Cutter, Tyler Walther, Kimberly H. Doyle, Ryan Frank. Hypoxia signaling pathway plays a role in ovarian cancer chemoresistance [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4525. doi:10.1158/1538-7445.AM2017-4525
Abstract 4533: In silico analysis of enhanced radiosensitivity in radiation treatment combined with androgen deprivation therapy for prostate cancer
Authors: Qian Mengdi , Almasan Alexandru , Gürkan-Çavusoglu Evren
Published: July 2017

The purpose of this study is to quantitatively analyze the improved radiosensitivity of prostate cancer cells to ionizing radiation (IR) when radiation treatment is combined with androgen deprivation therapy (ADT). The double strand breaks (DSBs) induced by ionizing radiation are repaired primarily by non-homologous end joining (NHEJ). It is reported in the literature that NHEJ is impaired after ADT, which then results in increased radiosensitivity and better IR treatment outcomes in prostate cancer. In this study, we have used our models for NHEJ repair of DSBs under IR treatment and IR + ADT combination treatment conditions to determine how the combination treatment results in better outcomes. We have modeled the effect of multiple doses of IR that are delivered 24 hours apart to mimic the conventional, fractionated radiation treatment. The analysis results showed that the DSBs accumulate more in the case of combined treatment with ADT compared to faster and more efficient repair when only IR is applied. We have used the experimental data on relative cell numbers and relative sub-G1 cell numbers from the literature to determine the difference in the levels of DSBs that lead to cell death differences between the two treatment strategies. The literature data also shows that there is patient response variability to ADT in terms of the reduction in the levels of Ku70/80, which is the first NHEJ protein complex that is recruited to DSBs. We have modeled this patient variability in our models by introducing variability to Ku70/80 protein concentrations used in the simulations. Our simulation results agree with the observation from clinical data that lower concentration levels of Ku70/80 lead to better radiosensitization. The amount of IR can be adjusted with respect to the level of radiosensitization after ADT on a patient specific level to achieve a desired level of DSBs that will lead to maximum cell death; this dose optimization effort will be the next step in our quantitative analysis.

Citation Format: Mengdi Qian, Alexandru Almasan, Evren Gürkan-Çavusoglu. In silico analysis of enhanced radiosensitivity in radiation treatment combined with androgen deprivation therapy for prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4533. doi:10.1158/1538-7445.AM2017-4533
Abstract 4534: Theory and methodology for the design and analysis of PDX mouse clinical trials
Authors: Guo Sheng , Mao Binchen , Li Henry Q.
Published: July 2017

Patient-derived xenograft (PDX) is a well-accepted experimental cancer model mimicking original patients in histo- & molecular pathology, as well as drug response. Mouse clinical trials (MCT) using PDX becomes increasingly prevalent in oncology research, yet the theory and methodology for trial design and analysis is underdeveloped. By analyzing tumor growths of 34081 PDX mice, we showed that majority of them can be satisfactorily modeled by exponential growth kinetics, based on which we derived a new drug response readout called the AUC ratio that is superior to the tumor growth inhibition (TGI) and its variants. We outlined a bootstrap algorithm to calculate its confidence interval, and showed that a 4:4 (4 mice in both treatment groups) or up design sharply increases measurement accuracy over the lesser design. Next, we introduce three approaches for drug evaluation and biomarker discovery in MCTs. In the end-point based analysis, we used a cohort of gastric PDXs to show a positive correlation between EGFR mRNA expression and cetuximab efficacy, in agreement with clinical trial results. We then used linear mixed models (LMMs) to describe MCTs as clustered longitudinal studies that capture the growth and drug response heterogeneities across PDXs and among mice within a PDX. Further, LMMs can separate prognostic and predictive biomarker effects, quantify response difference to a drug for multiple cancers, or efficacy difference of multiple drugs to a cohort of PDXs. Thirdly, we used additive frailty models to perform survival analysis on MCTs. We defined survival endpoints of PFS and OS in PDXs, and showed that hazard ratios can be more accurately estimated. We revealed an inherent connection between frailty and growth rate for PDXs. We performed computational simulations for the last two methods to show that statistical power improves tremendously with a 3:3 or up design. This work lays the foundation for rational design and analysis of PDX mouse clinical trials.

Citation Format: Sheng Guo, Binchen Mao, Henry Q. Li. Theory and methodology for the design and analysis of PDX mouse clinical trials [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4534. doi:10.1158/1538-7445.AM2017-4534
Abstract 4539: Novel feature selection strategies for enhanced predictive modeling and deep learning in the biosciences
Authors: Yang Pengwei , Abo Ryan , Liu Chang , Chen Zehua , Wu Haiguo , Cui Jike , Yandava Chandri , Bailey Shannon T. , Balch Curt , Gulcher Jeffery R. , Chittenden Thomas W.
Published: July 2017

Artificial Intelligence (AI) is the single most transformative technology in human history. Advancements in personalized medicine depend upon significantly furthering our current understanding of how genetic variation and somatic mutation regulate aberrant gene activity and subsequent disease biology, including the myriad of dysregulated molecular mechanisms of cancer. To this end, we have built a robust AI method to precisely assess pathogenicity for all genomic missense variants. Coupled with our advanced deepCODE feature selection strategy for constructing deep learning models, we can quantitatively integrate a priori pathway-based biological knowledge with multiple types of high-throughput omics data. This approach significantly improves performance of established classification methods via enhanced semantic interoperability for mapping between multiple biomedical ontologies and the subsequent identification of genes and molecular pathways more highly predictive of cancer type etiology. Specifically, our deepCODE AI methods greatly improve tumor subtype and drug-response classification accuracies by combining tumor DNA- and RNA-seq data. Our results indicate classification of human breast and lung cancer subtypes with 96% and greater than 99% accuracy, respectively. Our novel multinomial statistical-learning method, which was validated with 6 cancer type patient-derived tumor xenograft (PDTX) mouse models, achieved greater than 95% accuracy across 10,000 human tumors within the collection of 28 TCGA cancer types. Finally, our stepwise deepCODE drug target discovery approach systematically integrates our deep learning classification strategy with advanced Bayesian Network modeling to identify causative driver genes, representing probable novel drug targets. This stepwise machine learning approach also serves as a unique means to assess drug efficacy. Taken together, our advanced deepCODE AI tools greatly expand the means to fully understand the underlying molecular determinants of human cancer. We have developed user-friendly decision support and research tools for in-depth tumor analysis and large-scale case-control methods that afford investigators access to our deepCODE variant annotation algorithms.

Citation Format: Pengwei Yang, Ryan Abo, Chang Liu, Zehua Chen, Haiguo Wu, Jike Cui, Chandri Yandava, Shannon T. Bailey, Curt Balch, Jeffery R. Gulcher, Thomas W. Chittenden. Novel feature selection strategies for enhanced predictive modeling and deep learning in the biosciences [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4539. doi:10.1158/1538-7445.AM2017-4539
Abstract 4584: High PD-1 expression on regulatory and effector T cells in lung cancer draining lymph nodes
Authors: Ven Rieneke Van De , Niemeijer Anna-Larissa N. , Stam Anita G. , Hashemi Sayed M. , Slockers Christian G. , Daniels Johannes M. , Thunnissen Erik , Smit Egbert F. , Gruijl Tanja D. de , Langen Adrianus J. de
Published: July 2017

The treatment of advanced non-small cell lung cancer (NSCLC) with PD-1 immune checkpoint inhibitors has improved clinical outcome for a proportion of patients. The current challenge is to find biomarkers that will identify patients likely to benefit from this therapy. In this study we assessed the difference of T cell subsets and PD-1 expression levels on T cells in tumor-draining lymph nodes (TDLN), non-TDLN (NTDLN) and peripheral blood mononuclear cells (PBMC).

To evaluate this, flow cytometric analyses were performed on endobronchial ultrasound-guided (EBUS) fine-needle aspirates (FNA) from TDLN and NTDLN of patients with NSCLC and compared to PBMC.

Our data show that the frequency of PD-1+ CD4+ and CD8+ T cells, as well as the PD-1 expression level on activated regulatory T (aTreg) and CD4+ and CD8+ T cells, are higher in TDLNs as compared to NTDLNs or PBMC.

These elevated PD-1 expression levels in TDLN may reflect tumor-specific T cell priming and may serve as a predictive or early response biomarker during PD-1 checkpoint blockade.

Citation Format: Rieneke Van De Ven, Anna-Larissa N. Niemeijer, Anita G. Stam, Sayed M. Hashemi, Christian G. Slockers, Johannes M. Daniels, Erik Thunnissen, Egbert F. Smit, Tanja D. de Gruijl, Adrianus J. de Langen. High PD-1 expression on regulatory and effector T cells in lung cancer draining lymph nodes [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4584. doi:10.1158/1538-7445.AM2017-4584
Abstract 4605: Efficient targeting of BCMA-positive multiple myeloma cells by antibody-coupled T-cell receptor (ACTR) engineered autologous T cells in combination with an anti-BCMA antibody
Authors: Cheema Tooba , Hickman Taylor , O'Callaghan Katie , Westendorf Lori , Manlove Luke , Gardai Shyra , Nelson Allison , Boomer Ryan , McGinness Kathleen , Schultes Birgit , Ettenberg Seth , Sussman Django , Huet Heather
Published: July 2017

B cell maturation antigen (BCMA) has recently emerged as an attractive therapeutic target in multiple myeloma. BCMA has restricted expression on plasma cells with little to no expression on other normal tissues, but is upregulated on the surface of multiple myeloma cells. BCMA can regulate proliferation and survival of myeloma cells via binding to its ligands APRIL and BAFF and induce downstream signaling pathways. Thus, several approaches to target BCMA are currently under clinical investigation, including chimeric antigen receptor (CAR) T cell therapies, bispecific antibodies and antibody drug conjugates.

The Antibody-Coupled T cell Receptor (ACTR) technology is a universal, engineered T cell therapy consisting of the extracellular domain of human CD16 and the intracellular T cell co-stimulatory and signaling domains. ACTR is designed to engage the Fc domain of therapeutic antibodies opsonized to target cells to mediate anti-tumor activity. Previous work has demonstrated ACTR T cell activity in combination with rituximab, trastuzumab, and hu14.18 K322A against CD20, Her2, and GD2 expressing cell lines, respectively (Kudo et al. Cancer Res 2014; 74:93-103). Currently ACTR is being evaluated in Phase I clinical trials with rituximab to treat relapsed refractory B cell lymphoma.

Here we demonstrate a humanized afucosylated anti-BCMA antibody, SEA-BCMA, binds to ACTR expressing T cells with high affinity and mediates T cell activation, potent cytotoxicity, cytokine release and proliferation across a wide range of BCMA expressing myeloma cells. ACTR activity was specific to SEA-BCMA - opsonized target cells, dose dependent and had no activity on BCMA negative tumor lines. Furthermore, the SEA-BCMA antibody has additional properties that might contribute to a therapeutic effect, including blocking the binding of ligands to BCMA and driving natural killer cell mediated ADCC effects. These preclinical studies demonstrate a promising multi-faceted activity of ACTR T cells in combination with the anti-BCMA antibody, SEA-BCMA, for clinical consideration in multiple myeloma patients.

Citation Format: Tooba Cheema, Taylor Hickman, Katie O'Callaghan, Lori Westendorf, Luke Manlove, Shyra Gardai, Allison Nelson, Ryan Boomer, Kathleen McGinness, Birgit Schultes, Seth Ettenberg, Django Sussman, Heather Huet. Efficient targeting of BCMA-positive multiple myeloma cells by antibody-coupled T-cell receptor (ACTR) engineered autologous T cells in combination with an anti-BCMA antibody [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4605. doi:10.1158/1538-7445.AM2017-4605
Abstract 4614: Upregulation of memory T cell population and enhancement of Th1 response by lenvatinib potentiate antitumor activity of PD-1 signaling blockade
Authors: Kato Yu
Published: July 2017

Introduction: Lenvatinib (LEN) selectively inhibits the kinase activity of VEGFR1-3, FGFR1-4, KIT, PDGFRα, and RET, which are involved in tumor angiogenesis and tumor cell proliferation in several cancer types. Currently, Phase 1b/2 clinical trials of the combination of LEN and pembrolizumab (a monoclonal antibody [mAb] that blocks the interaction between PD-1 and its ligands) are ongoing for selected types of cancer including renal cell carcinoma, melanoma and non-small cell lung carcinoma. We have reported that tumor associated macrophage and regulatory T cell population were downregulated by treatment of LEN. In this study, mechanism of LEN and PD-1 mAb combination was investigated by flow cytometory and RNA-seq analyses.

Experimental Procedure: We examined antitumor activity of combination treatment of LEN (10mg/kg, qd) and anti-mouse PD-1 mAb (500μg/mouse, twice weekly) in Ct26 and B16F10 syngeneic mouse models. In order to investigate tumor-specific memory T cell response, re-inoculation of fresh CT26 cells into tumor-free mice was conducted. For immune cell population analyses, tumor or spleen samples were analyzed by flow cytometry. Changes of molecular immune response in tumors were examined by RNAseq followed by weighted gene co-expression network analysis (WGCNA).

Summary of data: Combination of LEN with PD-1 mAb showed more potent anti-tumor growth activity in CT26 and B16F10 models compared with either treatment alone. Notably, complete tumor regression was detected in a portion of mice that received combination treatment only. Re-inoculation of fresh CT26 cells into these tumor-free mice did not grow tumor; in contrast, all naïve animals grew tumor aggressively in the same experimental condition. RNAseq analysis of treated CT26 tumors indicated that combination of LEN with PD-1 mAb synergistically up-regulates IFN signaling-related genes. Flow cytometory analysis revealed that LEN increased memory T cell population compared with vehicle treatment.

Conclusions: The results indicate that the combination of LEN with PD-1 mAb was more effective than either single agent alone in multiple syngeneic tumor models and was accompanied with a potent antitumor immune response, especially the up-regulation of memory T cell and Th1 activation by LEN.

Citation Format: Yu Kato. Upregulation of memory T cell population and enhancement of Th1 response by lenvatinib potentiate antitumor activity of PD-1 signaling blockade [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4614. doi:10.1158/1538-7445.AM2017-4614
Abstract 4615: Development of an antibody-drug conjugate with broad anticancer activity
Authors: Lin Siang-Yo , Szekely Zoltan , Lin Chen-Yong , Bertino Joseph R. , Rather Gulam Mohmad
Published: July 2017

Treatment for patients with advanced solid tumors that include triple negative breast cancer (TNBC), non-small cell lung cancer (NSCLC), and castrate resistant prostate cancer (CRPC), as well as Mantle Cell Lymphoma (MCL), while increasing survival is not curative. We have identified a membrane bound protease, “activated” matriptase, as an attractive target antigen for highly selective antibody delivery of cytotoxins as activated matriptase expression is restricted to epithelial tumors and some B-cell lymphomas. We generated a novel ADC by linking M69, a mouse antibody specific to activated matriptase, to monomethyl auristatin E (MMAE) via a PEGylated, releasable di-peptide linker as a proof-of-principle prototype. Both in cell lines and in human xenograft models of TNBC, NSCLC, CRPC and MCL, the conjugate was found to exhibit potent anticancer activity against all of these tumor types without toxicity. Encouraged by these results, we are also exploring the use of this ADC against gastric and pancreatic cancer, and in combination with chemotherapy and immunotherapy. As this is a mouse antibody, we are also generating a chimeric antibody for toxicity studies in primates.

Citation Format: Siang-Yo Lin, Zoltan Szekely, Chen-Yong Lin, Joseph R. Bertino, Gulam Mohmad Rather. Development of an antibody-drug conjugate with broad anticancer activity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4615. doi:10.1158/1538-7445.AM2017-4615
Abstract 4661: Omentin as an adjunct to CA-125 in detecting recurrent ovarian cancer
Authors: Lewis Kelsey , Yeung Chi Lam Au , Mok Samuel , Lu Karen
Published: July 2017

Omentin (Intestinal Lactoferrin Receptor ITLN1) is an adipokine that is mainly secreted by the mesothelial cells lining visceral adipose tissues. It has been shown in previous studies that ovarian cancer cells down-regulate omentin which allows increased proclivity to spread to the omentum. Levels of serum omentin are decreased in patients with high-grade serous ovarian cancer (HGSOC) compared with patients with benign gynecologic diseases. Moreover, survival correlation studies showed that patients with lower serum omentin level at the time of first treatment experienced significantly shorter survival times than those with higher levels of omentin. CA-125 is currently the only biomarker used to monitor progression and re-occurrence of ovarian cancer. To our best knowledge, the relationship between omentin and CA-125 has not been investigated previously. We hypothesize that omentin may be a clinically useful adjunct to CA-125 in detecting recurrent ovarian cancer.

92 serum samples were collected prospectively from 27 HGSOC patients during the postoperative period until recurrence was detected. Patients had an average of 3.37 follow up visits and CA-125 levels were concurrently established. Recurrence was determined by imaging or an increase from baseline in CA-125 level. Samples were stored frozen at -80 degrees Celsius until use for this study. Circulating omentin levels were quantified using commercially available enzyme-linked immunosorbent assay (ELISA) kits. The results showed that 24 patients experienced a rise in CA-125 level during the postoperative period and 12 of these patients had an associated decrease in serum omentin level (average = 127.8 ng/mL). A significant negative correlation between omentin and CA-125 levels was observed (p = 0.02).

This study provides the first evidence that omentin may be a clinically useful adjunct to CA-125 in detecting recurrent ovarian cancer and warrants further investigation.

Citation Format: Kelsey Lewis, Chi Lam Au Yeung, Samuel Mok, Karen Lu. Omentin as an adjunct to CA-125 in detecting recurrent ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4661. doi:10.1158/1538-7445.AM2017-4661
Abstract 4687: Characterization of the cryoablation-induced immune response in kidney cancer patients
Authors: Kato Taigo , Iwasaki Tomoyuki , Uemura Motohide , Nagahara Akira , Higashihara Hiroki , Osuga Keigo , Ikeda Yuji , Kiyotani Kazuma , Park Jae-Hyun , Nonomura Norio , Nakamura Yusuke
Published: July 2017

Cryoablation is one of promising treatment modalities for kidney cancer and expected to induce strong local immune response as well as systemic T cell-mediated immune reaction that may lead to regression of distant metastatic lesions. In this study, we collected tumor tissues from 14 kidney cancer patients, at the time points of pre-cryoablation and 3 months after cryoablation. In addition, blood samples were collected from 8 kidney cancer patients at the same time points. We applied a next generation sequencing approach to characterize T cell receptor beta (TCRB) repertoires using mRNA isolated from tumor tissues and peripheral blood mononuclear cells. To assess clonality of T cells, the diversity index of TCRB was calculated according to complementarity-determining region 3 sequences. Through TCRB repertoire analysis, we demonstrated expansion of certain T cell clones in tumor tissues by cryoablation. In addition, we found that proportions of abundant TCRB clonotypes (≥ 1% frequency among total TCRB reads) were significantly increased in the post-cryoablation tissue samples than those of pre-cryoablation tumor samples, suggesting that cryoablation could induce strong immune reactions in tumors with oligoclonal expansion of anti-tumor T cells. Interestingly, some of these TCRB clonotypes were also increased in peripheral blood, indicating that certain numbers of T cell clones may also circulate systemically and then attack tumor cells in distant regions. We also measured mRNA expression levels of immune-related genes in the tissue samples of pre- and post- cryoablation and found significantly elevated expression levels of CD8, CD4, Granzyme A, and CD11c along with high CD8/FOXP3 ratio in the post-cryoablation tissue samples. Furthermore, immunohistochemical analysis confirmed infiltration of a large number of CD11c-positive cells, probably representing macrophages and dendritic cells into the post-cryoablation tissues. Collectively, our findings revealed that cryoablation could induce both local and systemic immune responses associated with CD11c-positive cells infiltration and oligoclonal expansion of anti-tumor T cells. For the translation into clinics, unique TCR sequences identified in post-cryoablation tissues in individual patients can be applied to personalized TCR-engineered T cell therapy.

Citation Format: Taigo Kato, Tomoyuki Iwasaki, Motohide Uemura, Akira Nagahara, Hiroki Higashihara, Keigo Osuga, Yuji Ikeda, Kazuma Kiyotani, Jae-Hyun Park, Norio Nonomura, Yusuke Nakamura. Characterization of the cryoablation-induced immune response in kidney cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4687. doi:10.1158/1538-7445.AM2017-4687
Abstract 4688: AVID200: a novel computationally-designed TGF beta trap promoting anti-tumor T cell activity
Authors: O'Connor-McCourt Maureen D. , Lenferink Anne E. , Zwaagstra John , Sulea Traian , Collins Catherine , Singh Renu , Durocher Yves , Cantin Christiane , Koropatnick James
Published: July 2017

AVID200 is a computationally-designed, avidity-enhanced, receptor ectodomain-based trap that binds and neutralizes TGF-beta 1 and 3 with low pM potency. Of the three TGF-beta isoforms, blockade of TGF-beta 2 has been shown to promote cancer metastasis. Therefore, AVID200 is designed to inhibit TGF-beta 1 and 3 only. TGF-beta is a strongly immunosuppressive molecule that, when expressed by cancers, mediates escape from immune surveillance. Increased TGF-beta ligand promotes cancer progression by suppressing anti-tumor immunity, predominantly by suppressing recruitment and activation of anti-tumor T cells. Consequently, TGF-beta is an important therapeutic target in cancer.AVID200 immunotherapy blocks the capacity of TGF-beta 1 and 3 ligands to interact with their receptors. That blockage induces T cell infiltration into tumors, thereby promoting a "T cell-inflamed" tumor state. Multiple trap formats with differing in vitro blocking potency, biophysical traits, and circulating half-lives in rodents have been designed, synthesized, and tested. On the basis of favorable characteristics, the AVID200 molecule was selected for in vivo assessment of efficacy in inhibiting growth of syngeneic 4T1 triple negative breast cancer (TNBC) homografts in immunocompetent host mice. In addition, CD4+ and CD8+ T cells isolated from draining lymph nodes of 4T1 tumor-bearing mice, treated and untreated with AVID200 and other candidate TGF-beta traps, were assessed for activities important in anti-tumor immune activity. We report that AVID200 immunotherapy decreased T-cell apoptosis, stimulated T-cell proliferation in response to tumor cell lysate-loaded dendritic cells, and enhanced the capacity of T-cells to specifically recognize and kill 4T1 tumor cells in ex vivo 2D cultures. The effect of combining AVID200 with immune checkpoint inhibitors in the treatment of syngeneic homografts in immune-competent mice is being assessed. AVID200 is a promising new immunotherapy to selectively inhibit the TGF-beta 1 and 3 isoforms, thereby enhancing desirable anti-tumor immunity while avoiding the tumor-promoting effects resulting from TGF-beta 2 neutralization.

Citation Format: Maureen D. O'Connor-McCourt, Anne E. Lenferink, John Zwaagstra, Traian Sulea, Catherine Collins, Renu Singh, Yves Durocher, Christiane Cantin, James Koropatnick. AVID200: a novel computationally-designed TGF beta trap promoting anti-tumor T cell activity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4688. doi:10.1158/1538-7445.AM2017-4688
Abstract 4692: Local adjuvant treatment of clinical stage I-II melanoma with low dose CpG-B and/or GM-CSF: Long-term follow-up of three randomized controlled phase II trials
Authors: Koster Bas D. , Hout Mari F. van den , Sluijter Berbel J. , Molenkamp Barbara G. , Vuylsteke Ronald J. , Baars Arnold , Leeuwen Paul A. van , Scheper Rik J. , Tol Monique P. van den , Eertwegh Alfons J. van den , Gruijl Tanja D. de
Published: July 2017

Introduction: Currently, there is no widely used adjuvant treatment available to improve survival after surgical excision of localized melanoma. Here, we present the clinical outcome of patients who participated in three randomized phase-II trials and received low-dose local immunotherapy, which was shown to be safe and to boost loco-regional and systemic anti-melanoma T cell immunity.

Patients and Methods: In three single-center, single-blinded, randomized and placebo (saline) controlled phase-II clinical trials, patients with early stage melanoma were treated with 1) Granulocyte/Macrophage-Colony Stimulating Factor (GM-CSF), 2) unmethylated CpG type-B oligodeoxynucleotide CpG7909 (CpG-B), and 3) CpG-B, alone or combined with GM-CSF, through 1-4 intradermal injections at the site of the primary melanoma excision scar, within 7 days preceding re-excision and sentinel lymph node (SLN) biopsy. For clinical follow-up analysis, all treated patients were grouped together (treated group n=36) as were the patients who received saline (saline group n=28).

Results: 10-year recurrence-free survival rate in the treated group was 94% (95% CI 78-98) versus 48% (95% CI 21-71) in the saline group (P=0.005), hazard ratio (HR) for recurrence was 0.15 (95% CI 0.06-0.60) for the treated group. This apparent antitumor efficacy was in line with the observation upon pathological examination of less tumor positive SLN in the treated group (P=0.05). The 10-year distant recurrence-free survival rate in treated patients was also higher (94%, 78-98 versus 59%, 28-81, HR 0.22, 0.07-0.93; P=0.04).

Conclusion: Local low-dose immunotherapy in patients with early-stage melanoma may offer durable protection against distant recurrences. These findings warrant further clinical exploration of this local non-toxic immune potentiating regimen.

Citation Format: Bas D. Koster, Mari F. van den Hout, Berbel J. Sluijter, Barbara G. Molenkamp, Ronald J. Vuylsteke, Arnold Baars, Paul A. van Leeuwen, Rik J. Scheper, Monique P. van den Tol, Alfons J. van den Eertwegh, Tanja D. de Gruijl. Local adjuvant treatment of clinical stage I-II melanoma with low dose CpG-B and/or GM-CSF: Long-term follow-up of three randomized controlled phase II trials [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4692. doi:10.1158/1538-7445.AM2017-4692
Abstract 4700: Poly G oligonucleotide enhances anti-tumor immune response among the patients with primary lung cancer
Authors: Kobayashi Nobuaki , Shibata Yuji , Yamamoto Masaki , Sato Takashi , Shinkai Masaharu , Koizumi Harumi , Takahashi Kenichi , Kudo Makoto , Shirota Hidekazu , Kaneko Takeshi
Published: July 2017

Synthetic oligonucleotides (ODNs) containing specific sequences have an immunomodulatory effect. It is highly expected that such ODNs can be developed into a novel anti-cancer immunotherapy with these effects. Our past data revealed that a novel poly-G ODN has an anti-tumor immune effect in the tumor-bearing murine model. This effect of poly-G ODN was mediated by T cells in a TLR9 independent manner. Poly-G ODN directly induced the phosphorylation of Lck, thereby enhancing the production of IL-2 and T cell proliferation. Meanwhile, our recent data suggested that the immune effect by poly-G ODN against cancer was different in human. We identified poly-G ODN induced T cell proliferation and production of IFN-gamma through the enhancement of monocyte maturation in human mononuclear cells isolated from peripheral blood or malignant pleural effusion of lung cancer patients. Further studies are continued for the establishment of a novel anti-cancer immune therapy with poly-G ODN.

Citation Format: Nobuaki Kobayashi, Yuji Shibata, Masaki Yamamoto, Takashi Sato, Masaharu Shinkai, Harumi Koizumi, Kenichi Takahashi, Makoto Kudo, Hidekazu Shirota, Takeshi Kaneko. Poly G oligonucleotide enhances anti-tumor immune response among the patients with primary lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4700. doi:10.1158/1538-7445.AM2017-4700