bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract IA21: NCI's Patient-Derived Models Repository: Generating models from racial and ethnic minorities
Authors: Evrard Yvonne A.
Published: February 2019

The National Cancer Institute (NCI) has developed a Patient-Derived Models Repository (PDMR) comprising quality-controlled, early-passage, clinically annotated patient-derived xenografts (PDXs) to serve as a resource for public-private partnerships and for academic drug discovery efforts. The first 100 models were released in May 2017, are clinically annotated with pathologic and molecular information available in a publicly accessible database, and are available to the extramural community for research use (pdmr.cancer.gov). The PDMR was established by NCI at the Frederick National Laboratory for Cancer Research (FNLCR) in direct response to discussions with academia and industry; the oncology community's highest-priority need was identified as better preclinical models that more faithfully reflect the patient's tumor and are associated with the patient's treatment history. NCI has focused on collecting specimens from patients with cancers that are under-represented in many other PDX collections such as head and neck, pancreatic, bladder and gynecologic cancers, melanomas, and sarcomas. Recently, NCI has also increased its focus on generation of PDXs from racial and ethnic minorities through new funding opportunities. The initial goal is to have 20-25% of the models in the PDMR from racial and ethnic minorities in diagnoses that are most pertinent to cancer health disparities. The overall goal of NCI is to create a long-term home for at least 1,000 models such that sufficient biologic, clinical, and population diversity is represented to allow researchers to ask questions such as: what is the impact of tumor heterogeneity on target qualification or clinical response; do PDXs more faithfully represent the human tumor for pharmacodynamic assay and predictive marker development; or can an adequately powered preclinical PDX clinical trial lead to better evaluation of therapies for future clinical use?

Grant Support: This project has been funded in part with federal funds from the National Cancer Institute, National Institutes of Health, under Contract No. HHSN261200800001E. The content of this publication does not necessarily reflect the views or policies of the Department of Health and Human Services, nor does mention of trade names, commercial products, or organizations imply endorsement by the U.S. government.

Citation Format: Yvonne A. Evrard. NCI's Patient-Derived Models Repository: Generating models from racial and ethnic minorities [abstract]. In: Proceedings of the Tenth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2017 Sep 25-28; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2018;27(7 Suppl):Abstract nr IA21.
Abstract A01: Stem cell signals in the initiation and progression of non-small cell lung cancer
Authors: Barber Alison G. , Husain Hatim , Valasek Mark A. , Scadeng Miriam , Reya Tannishtha
Published: February 2019

Lung cancer is most commonly diagnosed at a late stage when the disease is in its most aggressive state. To define the key regulators of lung cancer, we have focused on how stem cell signals are hijacked to drive progression to an undifferentiated state. Using a novel reporter mouse designed to reflect expression of the stem cell fate determinant Musashi-2 (Msi2), we found that Msi2 is highly expressed in tumors derived from the KrasG12D/+; p53fl/fl (KP) mouse model of lung adenocarcinoma. To test if Msi2-expressing cells preferentially act as the cell of origin in lung cancer, we isolated lung epithelial cells and tested their tumorigenic potential in vitro and in vivo following activation of Kras and loss of p53. Importantly, Msi2+ cells preferentially formed tumorspheres in vitro as well as tumors in vivo, indicating that Msi2+ tumor cells have increased tumor-initiating capacity. To determine whether Msi2 is required for lung cancer growth and progression, we crossed KP mice to Msi2 knockout mice and monitored tumor growth over time. Loss of Msi2 led to a reduction in both the number of tumors that formed and in overall tumor burden. Moreover, the mice exhibited a reduced frequency of high-grade tumors and an increase in overall survival, suggesting that loss of Msi2 impairs tumor development and disease progression. Finally, inhibition of Msi2 in a primary lung adenocarcinoma cell line led to reduced tumor volume in vivo, suggesting that Msi2 continues to be a dependency in established disease. Collectively, our data identify Msi2 as a stem cell signal that is critically required in lung cancer development and progression.

Citation Format: Alison G. Barber, Hatim Husain, Mark A. Valasek, Miriam Scadeng, Tannishtha Reya. Stem cell signals in the initiation and progression of non-small cell lung cancer [abstract]. In: Proceedings of the Fifth AACR-IASLC International Joint Conference: Lung Cancer Translational Science from the Bench to the Clinic; Jan 8-11, 2018; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(17_Suppl):Abstract nr A01.
Abstract A31: Loss of RNA editing of miR-99a-5p is a potential prognostic biomarker in completely resected lung adenocarcinoma
Authors: Maemura Keita , Watanabe Kousuke , Ando Takahiro , Hiyama Noriko , Sakatani Toshio , Amano Yosuke , Kage Hidenori , Takai Daiya
Published: February 2019

Adenosine-to-Inosine (A-to-I) RNA editing of microRNAs affects tumor phenotypes in various cancer types both in vitro and in vivo. For example, in melanoma cell lines, reduced RNA editing in miR-455-5p promotes metastasis through inhibition of a tumor-suppressor gene, CPEB1. For another example, in glioblastoma cell lines, accumulation of unedited miR-376a-3p and downregulation of edited miR-376a-3p promotes migration and invasion through inhibition of RAP2A and upregulation of AMFR, respectively. However, the difference in the editing level of microRNAs between cancers and the corresponding noncancerous tissues in humans is largely unknown.

In this study, we examined microRNA deep sequencing data in silico. The previously reported perl scripts to detect microRNA editing events used release 18 (November 2011) from miRBase as reference. Therefore, we revised the scripts to use the latest version, release 21 (June 2014). Analysis of public data of 74 cases of lung adenocarcinoma from sequence read archive (SRA) revealed eight microRNAs that underwent A-to-I RNA editing in at least five cases of both the tumor samples and the corresponding noncancerous samples. The editing levels of miR-379-5p, miR-99a-5p, and miR-497-5p were lower in the tumor samples than in the normal counterparts. The editing level of miR-200b-3p was higher in the tumor samples than in the normal counterparts. Among these four microRNAs, miR-99a-5p showed the largest difference in the editing level between the tumors and the normal counterparts.

Then we examined the editing level of miR-99a-5p in 50 cases of surgically resected lung adenocarcinoma at our institution by an original conventional sequence-based method. The editing level of miR-99a-5p was significantly lower in the tumor samples than the corresponding noncancerous samples in 19 cases (38%). The loss of RNA editing of miR-99a-5p was not associated with any clinical characteristics, such as sex, smoking history, pathologic stage, and EGFR mutation. These 19 cases showed a tendency toward a shorter recurrence-free survival (RFS) using the log rank test (P = 0.103) and a Cox proportional hazards model (hazard ratio, 1.91; 95% confidence interval, 0.87-4.19; P = 0.109). These results indicate that the loss of RNA editing of miR-99a-5p is a potential prognostic biomarker in patients with completely resected lung adenocarcinoma.

Citation Format: Keita Maemura, Kousuke Watanabe, Takahiro Ando, Noriko Hiyama, Toshio Sakatani, Yosuke Amano, Hidenori Kage, Daiya Takai. Loss of RNA editing of miR-99a-5p is a potential prognostic biomarker in completely resected lung adenocarcinoma [abstract]. In: Proceedings of the Fifth AACR-IASLC International Joint Conference: Lung Cancer Translational Science from the Bench to the Clinic; Jan 8-11, 2018; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(17_Suppl):Abstract nr A31.
Abstract B07: Characterization of branched-chain aminotransferase 1 as a novel therapeutic target for small cell lung cancer
Authors: Butler Napoleon B. , Kim Keebeom , Kim Dong-wook , Park Kwon
Published: February 2019

Few studies have explored tumor metabolism to target small cell lung cancer (SCLC), for which treatment options are limited and eventually fail with resistance. The objective of this study is to identify novel biomarkers and therapeutic targets among molecular changes specific to the cancer cells relative to precancerous precursor cells. In our previous study, comparative profiling of precancerous cells with SCLC cells revealed branched-chain aminotransferase1 (Bcat1) as one of the most upregulated genes in the cancer cells relative to their precursors as well as normal lung. Based on this result, we hypothesize that the elevated Bcat1 plays a role in promoting SCLC. Here, we confirmed elevated Bcat1 protein expression in mouse SCLC cells relative to precancerous cells and in human SCLC lines. Targeting Bcat1 in mouse and human SCLC cells with shRNA or small-molecule inhibitors significantly reduced colony expansion in soft agar and formation of subcutaneous tumors in athymic nude mice. Inhibition of Bcat1 also reduced protein synthesis rate as measured by puromycin incorporation into protein. Additionally, we found Bcat1 plays a significant role in leucine catabolism in mouse SCLC using a coupled enzymatic assay. Taken together, these novel findings suggest that elevated Bcat1 promotes SCLC growth by supporting protein synthesis, which is necessary for proliferating cells. Given the proven safety profile of existing inhibitors of Bcat1, our findings are significant in supporting the concept of targeting Bcat1 as a novel and particularly valuable therapeutic strategy for SCLC.

Citation Format: Napoleon B. Butler, Keebeom Kim, Dong-wook Kim, Kwon Park. Characterization of branched-chain aminotransferase 1 as a novel therapeutic target for small cell lung cancer [abstract]. In: Proceedings of the Fifth AACR-IASLC International Joint Conference: Lung Cancer Translational Science from the Bench to the Clinic; Jan 8-11, 2018; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(17_Suppl):Abstract nr B07.
Abstract B08: Targeting NOTCH activation in small cell lung cancer through LSD1 inhibition
Authors: Augert Arnaud , Eastwood Emily , Ibrahim Ali H. , Wu Nan , Grunblatt Eli , Basom Ryan , Eaton Keith D. , Martins Renato , Poirier John , Rudin Charles M. , Milletti Francesca , Mack Fiona , MacPherson David
Published: February 2019

Small cell lung cancer (SCLC) is a recalcitrant, lethal tumor type for which little change to first-line standard-of-care treatment has been made over the last few decades. Unlike non-small cell lung cancer (NSCLC), SCLC harbors few actionable mutations for therapeutic intervention. Activation of NOTCH signaling impairs neuroendocrine differentiation and suppresses SCLC, but there are no therapeutic strategies to activate NOTCH in SCLC. LSD1 inhibitors were previously shown to have selective activity in SCLC models, but the underlying mechanism was unknown. Here we demonstrate that exposure to the highly potent and selective LSD1 inhibitor, RG6016/ORY1001, induces NOTCH pathway activation, resulting in the suppression of ASCL1, a regulator of neuroendocrine cell state critical for SCLC oncogenesis. LSD1 binds to the NOTCH1 locus, modulating NOTCH1 expression in SCLC cells. In vivo, sensitivity to LSD1 inhibition in SCLC patient-derived xenograft (PDX) models correlates with the extent of NOTCH pathway activation and repression of a neuroendocrine phenotype. LSD1 inhibition represents a novel therapeutic approach to target the activation of NOTCH and suppression of ASCL1 in SCLC.

Citation Format: Arnaud Augert, Emily Eastwood, Ali H. Ibrahim, Nan Wu, Eli Grunblatt, Ryan Basom, Keith D. Eaton, Renato Martins, John Poirier, Charles M. Rudin, Francesca Milletti, Fiona Mack, David MacPherson. Targeting NOTCH activation in small cell lung cancer through LSD1 inhibition [abstract]. In: Proceedings of the Fifth AACR-IASLC International Joint Conference: Lung Cancer Translational Science from the Bench to the Clinic; Jan 8-11, 2018; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(17_Suppl):Abstract nr B08.
Abstract B10: Radiomics signatures on the region defined by using multi-window CT to improve detection lung cancer screening
Authors: Lu Hong , Mu Wei , Balagurunathan Yoganand , Qi Jin , Schabath Mathew , Gillies Robert James
Published: February 2019

Purpose: To evaluate the utility of defining a region using complementary information provided by different CT windows on the lung nodules to predict malignancy.

Methods: We obtained 50 cases from National Lung Screening Trial (NLST) with 23 malignant and 27 benign patients. We segmented lung nodules using lung and mediastinal window independently and obtained the difference region (3D). About 260 quantitative radiomics features were exacted on the voxels segmented from different windows and the difference region. We used support vector machines (SVM) to build a predictive model to identify malignancy. We compared the effectiveness of the multi-window based features against single-lung window features using a 2-fold cross validation.

Results: We find several radiomics features in the difference region to be predictive of malignancy; the best univariate features was Run_Length_Nonuniformity differnce region had an AUC of 0.911.The best feature in the lung window was defined by Sum_Entropylung window, which had an AUC of only 0.825. While using cross-validataion (2-fold) we obtained a mean accuracy of 80.97% and an AUC of 0.8 (specificity and sensitivity of 0.887 and 0.712). Compared to single-window, the best predictive features had accuracy of 78.17% and AUC of 0.772 (specificity and sensitivity of 0.876 and 0.667).

Conclusions:The multi-window based radiomics features, especially the features from difference area, can improve diagnostic performance in differentiation of benign and malignant lung nodules to great extent.

Citation Format: Hong Lu, Wei Mu, Yoganand Balagurunathan, Jin Qi, Mathew Schabath, Robert James Gillies. Radiomics signatures on the region defined by using multi-window CT to improve detection lung cancer screening [abstract]. In: Proceedings of the Fifth AACR-IASLC International Joint Conference: Lung Cancer Translational Science from the Bench to the Clinic; Jan 8-11, 2018; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(17_Suppl):Abstract nr B10.
Abstract B18: Characterization and therapeutic harnessing of TRAIL’s pro-tumorigenic and pro-apoptotic functions in cancer
Authors: Montinaro Antonella , Hartwig Torsten , Karstedt Silvia von , Zubiaur Itziar Areso , Lemke Johannes , Taraborelli Lucia , Surinova Silvia , El-Bahrawy Mona A. , Walczak Henning
Published: February 2019

Tumor necrosis factor (TNF)-related apoptosis inducing ligand (TRAIL) is known for specifically killing many cancer cells. This has led to the clinical development of several agonists for TRAIL-Rs. However, while some cancer cells die in response to TRAIL, most primary cancer cells are resistant to TRAIL-based monotherapy. In resistant cells, TRAIL signaling can induce non-apoptotic, tumor-supporting effects. Hence, efficient therapy design requires understanding of the bivalent nature of TRAIL signaling. Here we demonstrate that, on the one hand, TRAIL–TRAIL-R signaling in cancer cells elicits the production of cytokines, most importantly CCL2, which promote the accumulation of alternatively activated, M2-like myeloid cells in the tumor microenvironment, consequently promoting tumor growth via a CCL2/CCR2 axis. On the other hand, we identified CDK9 inhibition as a powerful means to render many TRAIL-resistant cancer cells highly sensitive to TRAIL-induced apoptosis. Importantly, this combination was also highly effective in vivo and led to significant tumor regression in mouse models of lung cancer. Therefore, in certain cancer patients antagonizing endogenous TRAIL–TRAIL-R signaling may modulate the tumor microenvironment in favour of tumor regression, while in other cancer patients the combination of TRAIL-R agonists with CDK9 inhibitors should be considered as a highly active alternative therapy.

Citation Format: Antonella Montinaro, Torsten Hartwig, Silvia von Karstedt, Itziar Areso Zubiaur, Johannes Lemke, Lucia Taraborelli, Silvia Surinova, Mona A. El-Bahrawy, Henning Walczak. Characterization and therapeutic harnessing of TRAIL’s pro-tumorigenic and pro-apoptotic functions in cancer [abstract]. In: Proceedings of the Fifth AACR-IASLC International Joint Conference: Lung Cancer Translational Science from the Bench to the Clinic; Jan 8-11, 2018; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(17_Suppl):Abstract nr B18.
Abstract B27: Osimertinib (AZD9291) is sensitive and bound with affinity to EGFR exon 20 insertion mutant models
Authors: Lee Yusoo , Kim Tae Min , Kim Dong-Wan , Ahn Yong-Oon , Kim Soyeon , Keam Bhumsuk , Kim Miso , Heo Dae Seog
Published: February 2019

Background: Although EGFR exon 20 insertion mutation is the third most common among EGFR-mutant NSCLC, this mutation has not been well studied and the first-generation EGFR TKIs are ineffective. In addition, the efficacy of the third-generation EGFR TKIs is controversial.

Methods: Various EGFR exon 20 insertion mutation models were developed using Ba/F3 system as follows: C-helix (n=1, A763_Y764insFQEA) and loop following C-helix (n=7). In addition, SNU-3173 cell line was derived from NSCLC patient with EGFR exon 20 insertion mutation. Cell viability assays were performed using EGFR TKIs (gefitinib, erlotinib, dacomitinib, afatinib, rociletinib, olmutinib, nazartinib, and osimertinib). Immunoblotting was performed to evaluate the downstream signals of EGFR pathway. Additionally, the docking homology models of EGFR exon 20 insertion mutations with osimertinib were developed with SWISS-Model and SwissDock for estimation of the structural appropriateness.

Results: Cell viability assay showed that EGFR exon 20 insertion mutants are resistant to the first-generation EGFR TKIs, except for A763_Y764insFQEA mutant Ba/F3 cells. IC50 values of second-generation EGFR TKIs are five- to hundreds-folds lower than gefitinib and erlotinib. Dacomitinib and afatinib have good efficacy for the most of them, and regulated down signaling pathways. The third-generation TKIs showed moderate efficacy against EGFR exon 20 insertion mutants. Overall, osimertinib has the most successful inhibition of EGFR exon 20 insertion mutants (IC50 values for C-helix and loop following C-helix mutants for afatinib, <0.1nM and 16.7-352.5nM; rociletinib 1022.1nM and 288.0-3034.6nM; olmutinib, 351.8nM and 30.4-626.7nM; osimertinib 131.6nM and 14.7-65.7nM; and nazartinib, 351.8nM and 36.3-509.9nM, respectively). Ribbon diagram with in silico homology docking simulations showed how exon 20 insertion mutations change the structures of kinase domain and the suitable binding values with various EGFR exon 20 insertion mutant subtypes with osimertinib.

Conclusions: Osimertinib showed an outstanding effectiveness against various EGFR exon 20 insertion mutations. In addition, docking simulation of in silico homology models corresponded with the in vitro results. Consequently, osimertinib is effective against EGFR exon 20 insertion mutant models.

Citation Format: Yusoo Lee, Tae Min Kim, Dong-Wan Kim, Yong-Oon Ahn, Soyeon Kim, Bhumsuk Keam, Miso Kim, Dae Seog Heo. Osimertinib (AZD9291) is sensitive and bound with affinity to EGFR exon 20 insertion mutant models [abstract]. In: Proceedings of the Fifth AACR-IASLC International Joint Conference: Lung Cancer Translational Science from the Bench to the Clinic; Jan 8-11, 2018; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(17_Suppl):Abstract nr B27.
Abstract B37: Dissecting the playbook of cancer: Genomic analysis of 100,000 human tumors reveals elaborate patterns of activation of the RTK-RAS-MAPK pathway
Authors: Manning Gerard , Lounsbury Nicholas , Hartmaier Ryan , Trabucco Sally , Sokol Ethan , Rinaldi Jacob , Liu Jinfeng , Gnad Florian
Published: February 2019

This abstract is being presented as a short talk in the scientific program. A full abstract is printed in the Proffered Abstracts section (PR03) of the Conference Proceedings.

Citation Format: Gerard Manning, Nicholas Lounsbury, Ryan Hartmaier, Sally Trabucco, Ethan Sokol, Jacob Rinaldi, Jinfeng Liu, Florian Gnad. Dissecting the playbook of cancer: Genomic analysis of 100,000 human tumors reveals elaborate patterns of activation of the RTK-RAS-MAPK pathway [abstract]. In: Proceedings of the Fifth AACR-IASLC International Joint Conference: Lung Cancer Translational Science from the Bench to the Clinic; Jan 8-11, 2018; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(17_Suppl):Abstract nr B37.
Abstract A061: STING, an immune biomarker for colorectal cancer
Authors: Chon Hongjae , Kim Chan
Published: February 2019

Background: STING is an innate immune sensor for cytosolic DNA. The activation of STING signaling is indispensable in Type I interferon response and the evocation of anticancer immune response by CD8+ T-cells. The aim of this study is to characterize intratumoral STING expression pattern and its clinical implication in colorectal cancer (CRC). Methods: We analyzed STING and CD8 expression in 225 CRC patients who underwent surgical resection. Clinicopathologic variables and survival outcomes were analyzed according to STING expression level. Results: Distinct STING expression was observed in tumor specimens of CRCs. Patients with higher STING expression seemed to have early stage cancer (P = 0.001) with increased intratumoral CD8+ T-cell infiltration (P < 0.001), and less frequent lymphovascular invasion (P = 0.02). Compared to CRC patients with lower STING expression, those with higher STING expression had longer overall survival (P < 0.001) and recurrence-free survival (P < 0.001). The Cox proportional hazard model, adjusted for age, stage, and CD8+ T-cells, revealed that higher STING expression is an independent prognostic factor for a better overall survival (P = 0.012, hazard ratio 0.573, 95% CI 0.370 – 0.886). Conclusion: We have confirmed the distinct STING expression in CRC and demonstrated its independent prognostic value for the survival outcome, thereby suggesting the intratumoral STING expression as a potential immune biomarker for CRC.

Citation Format: Hongjae Chon, Chan Kim. STING, an immune biomarker for colorectal cancer [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A061.
Abstract A067: Cognate interaction with CD4+ T-cells instructs M2-like macrophages to acquire M1-like phenotype
Authors: Eisel David , Osen Wolfram , Das Krishna , Hoerhold Franziska Marie-Claire , König Rainer , Eichmüller Stefan B.
Published: February 2019

Current tumor immunotherapy approaches are based on application of checkpoint inhibitors, such as monoclonal antibodies against PD-1/PD-L1 and CTLA-4 or adoptive T-cell therapy using ex vivo expanded TILs or genetically modified autologous T-cells expressing recombinant T-cell receptors (TCRs) or chimeric antigen receptors (CARs). However, the success of these therapeutic strategies is often limited by various inhibitory immune cell types accumulating in the tumor. In particular, tumor-associated macrophages (TAMs) contribute to the immune suppressive tumor micro-milieu, since so-called M2-like macrophages suppress the function of T effector cells and promote the differentiation of regulatory T-cells (Treg) through secretion of inhibitory cytokines such as TGF-β and IL10. Tumor antigen-specific CD4+ T effector cells, on the other hand, can essentially sustain antitumoral immune responses as shown for various tumor entities. In fact, using peritoneal exudate cells (PECs) as source for macrophages we demonstrate that MHC II restricted interaction between ovalbumin (OVA) specific CD4+ T-cells and M2-like macrophages drives M1 polarization. This was confirmed by detailed gene and protein expression analyses as well as functional assays testing phagocytic and pinocytic activities of repolarized macrophages. Moreover, in a set of preclinical experiments, adoptive transfer of CD4+, OVA-specific OT-II cells into C57BL/6 mice bearing OVA expressing IAb-/- tumors resulted in increased intratumoral number of M1-like TAMs as determined by gene expression analysis and flow cytometry. Furthermore, we observed a significant survival benefit of mice treated with a combination of OVA-specific CD4+ (OT-II) and CD8+ (OT-I) cells after transplantation of B16F10-Ova tumors and a complete response in some mice that rejected the tumor cells also upon a later re-challenge. While the antitumoral effect of this adoptive transfer experiment has been already described, we now offer a possible explanation for the supportive effect of specific CD4+ cells on co-transferred CD8+ cells. Taken together, the instructive impact of CD4+ T-cells on M2-like macrophages described in this presentation points towards a so far underestimated function of the CD4+ T-cell / TAM axis in reconditioning the immunosuppressive tumor micro-milieu.

Citation Format: David Eisel, Wolfram Osen, Krishna Das, Franziska Marie-Claire Hoerhold, Rainer König, Stefan B. Eichmüller. Cognate interaction with CD4+ T-cells instructs M2-like macrophages to acquire M1-like phenotype [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A067.
Abstract A087: The immunosuppressive property of mesenchymal stem cell in an apoptotic tumor microenvironment
Authors: Li Anita K.Y. , Cao Carmen J.M. , Chan Godfrey C.F.
Published: February 2019

Mesenchymal stem cells (MSCs) are a heterogeneous population of multipotenT-cells and are capable of differentiating into certain cell types. They can be found within tumor core and constitute part of the tumor microenvironment. Their role in tumor progression remains contradictory with both sides arguing pro- and anti-tumor function. In regarding to the pro-tumor effect, MSCs have shown to have immunoregulatory properties—suppressing T lymphocytes, B lymphocytes and dendritic cells, thereby helping tumor cells to escape from the immune surveillance. However there are some studies that showed certain microenvironment and stimulation can drive MSC into a proinflammatory phenotype. During cancer therapy, large amount of apoptotic cells are released to the tumor microenvironment. The aim of this study is to investigate how an apoptotic microenvironment can affect the function of MSC on naïve T-cells. Apoptotic cells (ACs) were derived from the neuroblastoma cell line SK-N-LP treated with cisplatin for 24 hr; they were then co-cultured with the immortalised human MSC cell line (hTMSC). Naïve T-cells were isolated from peripheral blood mononuclear cells of healthy donors and further co-cultured with either hTMSC alone or AC-treated hTMSC (hTMSC-AC) for 5 days. Cell proliferation and phenotype were analyzed by flow cytometry. We demonstrated that hTMSCs have the ability to phagocytose AC. After engulfment, the hTMSC-AC were able to increase T-cell proliferation compared to those co-cultured with untreated hTMSC. The T-cells co-cultured with hTMSC-AC also showed a decrease in CD45RA expression, suggesting an increase in T-cell activation. Moreover, these T-cells had a higher expression level of interferon-gamma (IFN-γ) and a lower expression of FoxP3, indicating a shift towards proinflammatory effector T-cells and a reduction of regulatory T-cells. Consistent with other literature, hTMSC has the ability to supress T-cells’ activation and proliferation. However in the presence of AC, hTMSC immunosuppressive property was impeded, thereby heightening the immune response. Therefore the microenvironment can play a major factor in determining the role of MSC on tumor. Further investigation of the interaction of MSC with immune cells in an apoptotic tumor microenvironment can lead to a potential immunotherapy for neuroblastoma.

Citation Format: Anita K.Y. Li, Carmen J.M. Cao, Godfrey C.F. Chan. The immunosuppressive property of mesenchymal stem cell in an apoptotic tumor microenvironment [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A087.
Abstract A093: Immune resistance emerges from tumor-initiating stem cells
Authors: Miao Yuxuan , Fuchs Elaine
Published: February 2019

Stem cells have a remarkable capacity to self-renew, generate and repair tissues. Their long lifespan leaves stem cells vulnerable to acquiring mutations, which over time can cause them to initiate and propagate a tumor. These cancer stem cells (CSC) are endowed with many unique molecular features to drive tumorigenesis, as well as to promote resistance to cancer therapies. However, whether there are any specialized mechanisms enabling the cancer stem cells to overcome immune surveillance remains poorly understood. In this study, we designed a skin squamous cell carcinoma cancer model that can be effectively challenged by adoptive cell transfer (ACT)-based immunotherapy. By single cell-RNA-seq profiling the molecular signature and lineage-tracing the fate of any cancer cells that survive the ACT treatment, we discovered that a group of TGF-β responding CSCs resist ACT, resulting in tumor relapse. Probing mechanism, we found that during malignancy, CSCs selectively acquire CD80. Thought to be an immune cell ligand, stem cell CD80 engagement with Cytotoxic T lymphocyte antigen-4 (CTLA4) on activated cytotoxic T-cells attenuates their attack, and upon CD80 ablation or CTLA4 immunotherapy, CSCs become vulnerable, reducing tumor burden. Our findings place CSCs at the crux of how immune checkpoint pathways are activated.

Citation Format: Yuxuan Miao, Elaine Fuchs. Immune resistance emerges from tumor-initiating stem cells [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A093.
Abstract A118: Clinical impact of PD-L1 expression and epithelial-mesenchymal transition in the tumor microenvironment of extrahepatic cholangiocarcinoma
Authors: Tsuchikawa Takahiro , Ueno Takashi , Sato Osamu , Nakamura Toru , Nakanishi Yoshitsugu , Asano Toshimichi , Noji Takehiro , Okamura Keisuke , Shichinohe Toshiaki , Hirano Satoshi
Published: February 2019

Background: Extrahepatic cholangiocarcinoma (eCCA) has a poor prognosis. Although the possibility of immunotherapy has been studied, immune checkpoint molecules such as programmed death ligand 1 (PD-L1) in eCCA are not well understood. Epithelial-mesenchymal transition (EMT) has recently been shown to regulate PD-L1 expression. Our aims were to assess the clinicopathological significance of tumor-infiltrating lymphocytes (TILs) and tumor PD-L1 expression in eCCA and to compare these immune responses with EMT marker expression. Material and Methods: An immunohistochemical evaluation using a TMA method at a single large center was performed. Patients (n = 117) underwent surgical resection in the Department of Gastroenterological Surgery II at Hokkaido University Hospital between January 1995 and November 2006 and eCCA tumors were confirmed histopathologically. We investigated the level of infiltration of immune cells positive for CD4, CD8, Foxp3, PD-L1 in addition to E-cadherin, N-cadherin, Vimentin, ZEB1, ZEB2, SNAIL, TWIST expression, statistically comparing correlations among these factors. Results: High numbers of CD4+ and CD8+ TILs correlated with node-negative (P = 0.009 and P = 0.046, respectively) and low SNAIL expression (P = 0.016 and P = 0.022, respectively). High PD-L1 expression was associated with poor histopathologic classification (P = 0.034), and low E-cadherin (P = 0.001), high N-cadherin (P = 0.044), high vimentin (P < 0.001) and high ZEB1 (P = 0.036) expression. Multivariate analysis showed that CD4+ TILs, PD-L1 expression and N-cadherin expression were independent prognostic factors (hazard ratio (HR) = 0.61; 95% confidence interval (CI) = 0.38-1.00; HR=4.27; 95% CI = 1.82-9.39; HR = 2.20; 95% CI = 1.18-3.92, respectively). Summary: Present data suggested that CD4+ T lymphocyte tumor infiltration and PD-L1 expression on tumor cells were independent prognostic factors in eCCA. We also provided the first evidence that high tumor PD-L1 expression correlates with a mesenchymal phenotype.

Citation Format: Takahiro Tsuchikawa, Takashi Ueno, Osamu Sato, Toru Nakamura, Yoshitsugu Nakanishi, Toshimichi Asano, Takehiro Noji, Keisuke Okamura, Toshiaki Shichinohe, Satoshi Hirano. Clinical impact of PD-L1 expression and epithelial-mesenchymal transition in the tumor microenvironment of extrahepatic cholangiocarcinoma [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A118.
Abstract A120: Intratumoral dendritic cell dynamics in responsive and nonresponsive syngeneic murine tumor models
Authors: Xiong Huizhong , Mittman Stephanie , Rodriguez Ryan , Moskalenko Marina , Sanchez Patricia Pacheco , Yang Yagai , Cubas Rafael
Published: February 2019

Conventional dendritic cells (cDC) play a vital role in T-cell-mediated antitumor immunity by transporting and cross-presenting tumor antigens to CD8 T-cells in draining lymph nodes (dLN) and tumor tissue. DC maturation and antigen uptake takes place in the tumor, which can be heavily affected by the suppressive tumor microenvironment. Intratumoral DCs are a scarce population and their phenotypes and functions have not been fully understood. Here we thoroughly characterized cDC phenotypes and dynamics in a variety of commonly used syngeneic murine tumor models, both at baseline and following anti-PD-L1 (aPDL1) treatment to investigate the correlation and potential contribution of DCs to response. Surprisingly, we observed a lower density of intratumoral DCs in responsive tumor models when compared to nonresponsive ones and their abundance was further reduced by aPDL1 treatment in an IFNg-dependent manner. Their PDL1 expression levels, albeit lower than tumor macrophages, were positively correlated with response. These results demonstrate an inverse correlation between intratumoral DCs and aPDL1-mediated antitumor immunity across different syngeneic murine tumor models, and ongoing studies are exploring the fates of these intratumoral DCs with a focus on their causal relation with the efficacy of immunotherapy.

Citation Format: Huizhong Xiong, Stephanie Mittman, Ryan Rodriguez, Marina Moskalenko, Patricia Pacheco Sanchez, Yagai Yang, Rafael Cubas. Intratumoral dendritic cell dynamics in responsive and nonresponsive syngeneic murine tumor models [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A120.
Abstract A121: Single-cell transcriptomic analyses reveal heterogeneity of vascular endothelial cells in cancer models
Authors: Zhu Yu , Salazar Nicole , Brulois Kevin , Butcher Eugene
Published: February 2019

The immune system has demonstrated promising potential as a therapeutic target in the treatment of certain cancer types, yet in many tumors the efficacy of immunotherapies is still extremely poor. One major obstacle is the limited access of immune cells to the tumor tissue. The tumor vasculature plays critical roles in regulating the recruitment of anti-tumor immune cells and the delivery of immunotherapies to the tumor sites. These immune processes require functional specialization of endothelial cells (ECs). However, there is a major gap in our understanding of the diversity, molecular specialization, and developmental relationships of tumor-associated EC subsets. To understand the heterogeneity of tumor-associated endothelium, we performed single-cell RNA sequencing (scRNAseq) analyses on ECs isolated from mouse cancer models. scRNAseq identified several subsets of endothelium in the tumor tissue, including ECs that compose the artery, capillary, and post-capillary venules. Interestingly, within the capillary endothelial compartment, we identified an EC subset that resembles tip cells in sprouting angiogenesis and demonstrates molecular signature of stem or progenitor cells. These putative progenitor cells are dramatically expanded in tumors compared to normal tissues, and comprise both quiescent and proliferative populations. The quiescent ECs express high levels of genes coding for antiapoptotic proteins, extracellular matrix molecules, immune checkpoint molecules, monocyte/macrophage recruiting cytokines, and stem cell signaling components, such as Notch4. On the other hand, the proliferative tip-like ECs express genes coding for cyclins and cyclin-dependent kinases, DNA damage repair molecules, necroptosis machinery, and epigenetic regulators. Taken together, these data define the heterogeneity of tumor-associated endothelial cells, and reveal a putative progenitor population that gives rise to the tumor vasculature and could be targeted to improve the efficacy of immunotherapies.

Citation Format: Yu Zhu, Nicole Salazar, Kevin Brulois, Eugene Butcher. Single-cell transcriptomic analyses reveal heterogeneity of vascular endothelial cells in cancer models [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A121.
Abstract A132: Identification of pyroptosis inhibitors that target a reactive cysteine in gasdermin D
Authors: Hu Jun , Liu Xing , Zhao Jingxia , Xia Shiyu , Ruan Jianbin , Luo Xuemei , Kim Justin , Lieberman Judy , Wu Hao
Published: February 2019

Inflammasomes are multiprotein signaling scaffolds that assemble in response to invasive pathogens and sterile danger signals to activate inflammatory caspases (1/4/5/11), which trigger inflammatory death (pyroptosis) and processing and release of proinflammatory cytokines. Inflammasome activation contributes to many human diseases, including inflammatory bowel disease, gout, type II diabetes, cardiovascular disease, Alzheimer’s disease, and sepsis, the often fatal response to systemic infection. The recent identification of the pore-forming protein gasdermin D (GSDMD) as the final pyroptosis executioner downstream of inflammasome activation presents an attractive drug target for these diseases. Here we show that C-23 and C-27 potently inhibit GSDMD pore formation in liposomes and inflammasome-mediated pyroptosis and IL-1β secretion in human and mouse cells. Moreover, C-23, administered at a clinically well-tolerated dose, inhibits LPS-induced septic death and IL-1β secretion in mice. Both compounds covalently modify a conserved Cys (Cys191 in human and Cys192 in mouse GSDMD) that is critical for pore formation. Inflammatory caspases employ Cys active sites, and many previously identified inhibitors of inflammatory mediators, including those against NLRP3 and NF-κB, covalently modify reactive cysteine residues. Since NLRP3 and noncanonical inflammasome activation are amplified by cellular oxidative stress, these redox-sensitive reactive cysteine residues may regulate inflammation endogenously, and compounds that covalently modify reactive cysteines may inhibit inflammation by acting at multiple steps. Indeed, both C-23 and C-27 also directly inhibit inflammatory caspases and pleiotropically suppress multiple processes in inflammation triggered by both canonical and noncanonical inflammasomes, including priming, puncta formation and caspase activation. Hence, cysteine-reactive compounds, despite their lack of specificity, may be attractive agents for reducing inflammation.

Citation Format: Jun Hu, Xing Liu, Jingxia Zhao, Shiyu Xia, Jianbin Ruan, Xuemei Luo, Justin Kim, Judy Lieberman, Hao Wu. Identification of pyroptosis inhibitors that target a reactive cysteine in gasdermin D [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A132.
Abstract A133: APOBEC3 confers resistance to oncolytic VSV therapy
Authors: Huff Amanda L. , Wongthida Phonphimon , Kottke Timothy , Thompson Jill , Driscoll Christopher B. , Schuelke Matthew , Shim Kevin G. , Harris Reuben S. , Molan Amy , Pulido Jose S. , Selby Peter J. , Harrington Kevin J. , Melcher Alan , Evgin Laura , Vile Richard
Published: February 2019

Tumor cells are able to evade cytotoxic therapies through the accumulation of genomic mutations and rapid evolution. In the case of oncolytic virotherapy, understanding the mechanisms by which cancer cells develop resistance to infection and lysis is critical to the development of more effective viral-based platforms. Here, we identify APOBEC3 as an important factor involved in the restriction of vesicular stomatitis virus (VSV). We show that VSV infection of B16 murine melanoma cells upregulated APOBEC3 in an IFNβ-dependent manner, which was responsible for the evolution of virus-resistanT-cell populations and suggested that APOBEC3 expression promoted the acquisition of a virus-resistant phenotype. ShRNA knockdown of APOBEC3 in B16 cells diminished their capacity to develop resistance to VSV infection in vitro, and enhanced the therapeutic effect of VSV in vivo. Similarly, overexpression of human APOBEC3B promoted the acquisition of resistance to oncolytic VSV in murine melanoma and glioblastoma lines, as well as in a human melanoma cell line in vitro and in vivo. Finally, we demonstrate that progeny virus obtained after passage through APOBEC3B overexpressing cells contained more defective interfering particles, thereby indicating that APOBEC3B directly affected the fitness of VSV, an RNA virus that has not previously been identified to be restricted by APOBEC3B. This research identifies APOBEC3 enzymes as key players to target in order to improve the efficacy of oncolytic viruses as well as broader nucleic acid-based therapeutic platforms.

Citation Format: Amanda L. Huff, Phonphimon Wongthida, Timothy Kottke, Jill Thompson, Christopher B. Driscoll, Matthew Schuelke, Kevin G. Shim, Reuben S. Harris, Amy Molan, Jose S. Pulido, Peter J. Selby, Kevin J. Harrington, Alan Melcher, Laura Evgin, Richard Vile. APOBEC3 confers resistance to oncolytic VSV therapy [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A133.
Abstract A141: Intratumoral depletion of regulatory T-cells using CD25-targeted photodynamic therapy induces antitumoral immune responses
Authors: Lee Heung Kyu , Oh Dong Sun
Published: February 2019

Tumor immunotherapy aims to overcome the immunosuppressive microenvironment within tumors, and various approaches have been developed. Tumor-associated T regulatory cells (Tregs) suppress the activation and expansion of tumor antigen-specific effector T-cells, thus providing a permissive environment for tumor growth. Therefore, optimal strategies need to be established to deplete tumor-infiltrated Tregs because systemic depletion of Tregs can result in reduced anti-tumor effector cells and autoimmunity. Here, to deplete Tregs selectively in tumors, we intratumorally injected anti-CD25 antibodies conjugated to Chlorin e6 (Ce6), a photosensitizer that absorbs light to generate reactive oxygen species. Local depletion of tumor-associated Tregs by photodynamic therapy (PDT) inhibited tumor growth, which was likely due to the altered tumor immune microenvironment that was characterized by increased infiltration of CD8+ effector T-cells and the expression of IFN-γ and CD107a, which is cytolytic granule exocytosis marker, in tumor tissues. Furthermore, PDT-induced intratumoral Treg depletion did not influence adaptive immune responses in a murine influenza infection model. Thus, our results show that intratumoral Treg-targeted PDT could specifically modulate tumor microenvironments by depleting Tregs and could be used as a novel cancer immunotherapy technique.

Citation Format: Heung Kyu Lee, Dong Sun Oh. Intratumoral depletion of regulatory T-cells using CD25-targeted photodynamic therapy induces antitumoral immune responses [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A141.
Abstract A143: Glutaminyl cyclase is an enzymatic modifier of the CD47- SIRPα axis and target for immunotherapy
Authors: Logtenberg Meike Emma Willemijn
Published: February 2019

Cancer cells are able to evade immune surveillance through the expression of inhibitory ligands that bind their cognate receptors on immune effector cells. CD47 serves as a “don't eat me” signal for myeloid cells by binding to the inhibitory receptor signal-regulatory protein alpha (SIRPα). Prior work has provided strong evidence that antibody-based targeting of the CD47 axis can promote tumor control by both innate and adaptive immune cells, and clinical development of CD47 antagonists is ongoing. Using a haploid genetic screen, we identify glutaminyl-peptide cyclotransferase-like (QPCTL) as a regulator of the CD47-SIRPα checkpoint that is critical for pyroglutamate formation on CD47 at the SIRPα binding site. Both genetic and pharmacologic interference with QPCTL activity decrease SIRPα binding to CD47 and enhances antibody-dependenT-cellular phagocytosis and cellular cytotoxicity of tumor cells mediated by macrophages and neutrophils, respectively. Furthermore, interference with QPCTL expression leads to a major increase in tumor cell killing and neutrophil influx by tumor-opsonizing antibodies in vivo. These data provide an avenue for small-molecule inhibition of the CD47 pathway to augment antibody therapy of cancer.

Citation Format: Meike Emma Willemijn Logtenberg. Glutaminyl cyclase is an enzymatic modifier of the CD47- SIRPα axis and target for immunotherapy [abstract]. In: Proceedings of the Fourth CRI-CIMT-EATI-AACR International Cancer Immunotherapy Conference: Translating Science into Survival; Sept 30-Oct 3, 2018; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2019;7(2 Suppl):Abstract nr A143.