bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 3701: Mutant p53 cancers reprogram tumor-associated macrophages via exosomal miR-1246
Authors: Cooks Tomer , Pateras Ioannis S. , Jenkins Lisa M. , Patel Keval M. , Robles Ana I. , Morris James , Forshew Tim , Appella Ettore , Gorgoulis Vassilis G. , Harris Curtis C. 
Published: July 2017

Abstract
TP53 mutants (mutp53) are involved in the pathogenesis of most human cancers. Specific mutp53 proteins gain oncogenic functions (GOF) distinct from the tumor suppressor activity of the wild-type protein. Tumor-associated-macrophages, a hallmark of solid tumors, are typically correlated with poor prognosis. Here we report a non-cell-autonomous mechanism whereby mutp53 cancer cells reprogram TAM to a tumor supportive and anti-inflammatory state. The colon cancer cells harboring GOF mutp53 selectively shed miR-1246-enriched exosomes. Uptake of these exosomes by neighboring macrophages triggers their miR-1246 dependent reprogramming into a cancer-promoting state. Mutp53-reprogammed TAM favor anti-inflammatory immunosuppression with increased activity of TGF-β. These findings, observed also in colon cancer patients, strongly support a microenvironmental GOF role for mutp53 in actively engaging the immune system to promote cancer progression and metastasis.
Citation Format: Tomer Cooks, Ioannis S. Pateras, Lisa M. Jenkins, Keval M. Patel, Ana I. Robles, James Morris, Tim Forshew, Ettore Appella, Vassilis G. Gorgoulis, Curtis C. Harris. Mutant p53 cancers reprogram tumor-associated macrophages via exosomal miR-1246 [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 3701. doi:10.1158/1538-7445.AM2017-3701
Abstract 3702: Quantitative imaging of metabolic changes in macrophage subsets
Authors: Heaster Tiffany M. , Elion David L. , Cook Rebecca S. , Skala Melissa C. 
Published: July 2017

Abstract
Macrophages play an important role in tumor therapeutic response. However, current methods cannot image heterogeneities in macrophage activity on a single-cell level over time within intact, living samples. Macrophage metabolism is closely linked to macrophage function, as M1-like macrophages rely on aerobic glycolysis and M2-like macrophages rely on fatty acid oxidation and oxidative phosphorylation. Thus, we propose to develop optical metabolic imaging (OMI) using two-photon microscopy to monitor cell-level changes in macrophage polarization and functional activity. OMI exploits the auto-fluorescence intensities and lifetimes of the metabolic co-enzymes NAD(P)H and FAD, and has been previously used to dynamically image in vivo tumors with cell-level resolution. The optical redox ratio (fluorescence intensity of NAD(P)H divided by FAD) provides a global measure of redox balance within individual cells. The fluorescence lifetimes of NAD(P)H and FAD provide information in protein-binding activities in metabolic reactions. OMI was used to monitor metabolic changes in macrophages on a single-cell level during polarization and after metabolic perturbations. RAW 264.7 macrophages were stimulated towards an M1- or M2-like phenotype, and imaged with OMI at 24, 48, and 72 hours post-polarization. M1- and M2-like macrophages exhibited significant differences (p&lt;0.05) in redox ratio and FAD fluorescence lifetime values at 48 and 72 hours post-polarization. The M1-like and M2-like character of the macrophages were validated with quantitative polymerase chain reaction (qPCR) analysis. Population density modeling of single-cell metabolism established differences in intra-sample heterogeneity across subsets over time. M1- and M2-like macrophages were also treated with 2-deoxy-glucose (glycolysis inhibitor), etomoxir (fatty acid oxidation inhibitor), and cyanide (oxidative phosphorylation inhibitor. Treatment with etomoxir caused a significant decrease in redox ratio in M2-like macrophages (p&lt;0.05) with no significant effect on M1-like macrophages. In contrast, the redox ratio decreased in M1-like macrophages upon inhibition of glycolysis (p&lt;0.05). Comparable to previously published data, inhibition of oxidative phosphorylation in both groups yielded a decreased NAD(P)H mean lifetimes (p&lt;0.05) and increased FAD mean lifetimes (p&lt;0.05). These results establish OMI as a method to image heterogeneity in macrophage populations within intact, living samples. This method could be used to understand macrophage interactions in the microenvironment of intact in vivo tumors.
Citation Format: Tiffany M. Heaster, David L. Elion, Rebecca S. Cook, Melissa C. Skala. Quantitative imaging of metabolic changes in macrophage subsets [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 3702. doi:10.1158/1538-7445.AM2017-3702
Abstract 3705: Targeting interleukin-1 to increase cetuximab efficacy in head and neck cancer
Authors: Espinosa-Cotton Madelyn , McLaren Ayana J. , Koch Adam T. , Simons Andrean L 
Published: July 2017

Abstract
Treatment for head and neck squamous cell carcinoma (HNSCC) patients includes the epidermal growth factor receptor (EGFR) monoclonal antibody cetuximab. However, response to cetuximab is low and resistance remains a critical issue. Therefore, it is imperative to develop strategies to enhance tumor response to this drug. Inflammation plays an important role in tumor progression by increasing the release of cytokines that promote tumor cell survival. Our prior work has shown that a variety of pro-inflammatory cytokines involved in tumor survival are upregulated upon treatment with EGFR inhibitors in HNSCC cells, suggesting that poor tumor response to EGFR inhibitors may be due to increased tumor-associated inflammation. Our lab has shown that the increased proinflammatory tumor response due to EGFR inhibition may be activated by interleukin-1 (IL-1) signaling, suggesting that the IL-1 pathway may be an important target to enhance the efficacy of anti-EGFR therapy. Here we investigated the effect of IL-1 blockade on HNSCC tumor response to cetuximab treatment. We found that cetuximab induced IL-6 secretion from SQ20B HNSCC cells and knockdown of the adapter protein MyD88, which is essential for IL-1 signaling, suppressed IL-6 secretion at baseline and in response to cetuximab treatment. Similarly, knock down of the IL-1 receptor (IL-1R) decreased baseline and cetuximab-induced IL-6 secretion, although IL-1R knockdown did not improve response to cetuximab in SQ20B xenografts in vivo. We additionally blocked IL-1 signaling using a recombinant IL-1R antagonist (IL-1RA). IL-1RA pre-treatment reduced baseline and cetuximab-induced IL-6 secretion in vitro. Although IL-1RA did not significantly enhance SQ20B tumor response to cetuximab, IL-1RA as a single agent significantly suppressed tumor growth in female mice but not in male mice. Finally, treatment with a human-specific neutralizing IL-1 alpha (IL-1α) antibody (but not IL-1 beta (IL-1β)) reduced baseline and cetuximab-induced IL-6 secretion in vitro, and significantly increased SQ20B tumor response to cetuximab in vivo. Altogether we propose that targeting IL-1α specifically may be a viable strategy to improve HNSCC tumor response to cetuximab.
Citation Format: Madelyn Espinosa-Cotton, Ayana J. McLaren, Adam T. Koch, Andrean L, Simons. Targeting interleukin-1 to increase cetuximab efficacy in head and neck 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 3705. doi:10.1158/1538-7445.AM2017-3705
Abstract 3713: Higher numbers of cancer stem cells in the peripheral blood of children with B-ALL upon conventional chemotherapy
Authors: Salem Mohamed L. 
Published: July 2017

Abstract
Background: Acute lymphocytic leukemia (ALL) is biologically and clinically considered as a heterogeneous neoplasm of lymphoid progenitor cells in the bone marrow (BM). 15- 20 % of children with ALL who achieve an initial remission, will show relapse. One potential mechanism behind this relapse could be the emergence of cancer stem cells (CSCs) which are considered the driving force of tumourigenesis due to their ability of self-renewal as well as the emergence of immune regulatory cells including myeloid-derived suppressor cells (MDSCs) and regulatory T cells (Treg).
Aim: the main aim of this study was to analyze the numbers of CSCs and correlate these numbers with the numbers of blast cells, MDSCs and Treg cells in children with B-ALL before and after induction of chemotherapy.
Materials and Methods: CSCs were defined as CD45dimCD19+CD10+CD34+CD38-, MDSCs were defined as Lin-HLA-DR-CD33+CD11b+ and Treg cells were defined as CD4+CD25+CD127-. The frequencies of these cells were analyzed in the peripheral blood of B-ALL patients before (n= 10) and after (n= 10) induction of chemotherapy using flow cytometry.
Results: Significant increases in the numbers of CSCs were shown in B-ALL patients after induction of chemotherapy as compared to newly diagnosed patients (7.6± 8.3 vs. 2.7± 2.4, P&lt;0.05). The numbers of CSCs in ALL patents before and after induction of chemotherapy inversely correlated with the numbers of the blast cells. Additionally, the numbers of MDSCs and Treg cells were higher and lower, respectively, in patients after induction of chemotherapy as compared to before chemotherapy.
Conclusion: Our results indicate that chemotherapy of B-ALL patients results in emergence of high numbers of CSCs and MDSCs which might be contributing, respectively, to tumor relapse and creation of systemic immune suppression. This pilot study opens a new avenue to investigate the mechanism mediating the emergence of these cells on larger population of B-ALL patients at different treatment stages.
Note: This abstract was not presented at the meeting.
Citation Format: Mohamed L. Salem. Higher numbers of cancer stem cells in the peripheral blood of children with B-ALL upon conventional chemotherapy [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 3713. doi:10.1158/1538-7445.AM2017-3713
Abstract 3720: Biological and clinical relevance of PD-L1 expression in tumor and inflammatory cells in NSCLC
Authors: Bais Carlos , Morehouse Chris , Higgs Brandon W. , Marlon Rebelatto , Steele Keith , Jin Xiaoping , Shi Li , Korolevich Susana , Gupta Ashok , Ranade Koustubh 
Published: July 2017

Abstract
Background: High PD-L1 expression has been shown to be associated with improved clinical outcomes to anti-PD-1/L1 therapies in NSCLC and other indications. However, only a fraction of the PD-L1 high patients (pts) respond. PD-L1 can be induced by IFNG and expressed in tumor cells (TC) and inflammatory cells (IC). Improving our ability to predict patient benefit from anti-PD-1/L1 therapies requires a better understanding of associations between PD-L1 expression in TC and/or IC and outcome. Here we explore the relationship between patterns of IHC PD-L1 expression in TC and IC, gene expression, and clinical outcome.
Methods: CP1108/NCT01693562 was a nonrandomized phase 1/2 trial evaluating durvalumab in pts with advanced NSCLC or other solid tumors. As of 29 APR 2016, 368 previously treated NSCLC pts received durvalumab ≤12 months with a median 18.8 months follow up. Pts with ≥25% TC or IC were scored TC+ and/or IC+, respectively.
Results: TC+ PD-L1 pts (includes IC+ and IC- PD-L1 pts) had improved survival compared to TC- PD-L1 pts. TC+ and IC+ PD-L1 pts had: improved survival compared to TC+/IC-, TC-/IC+, or TC-/IC- PD-L1 pts. However, prevalence of TC+/IC+ was lower than TC+. Twenty-one genes significantly differed between TC+/IC+, TC+/IC-, TC-/IC+, and TC-/IC- PD-L1 patient subsets, the vast majority being well-known IFNG-inducible genes and mostly over-expressed in the TC+/IC+ subset.
Conclusions: TC+ and IC+ PD-L1 pts had the highest levels of IFNG-inducible gene expression, a key biological feature that distinguishes PD-L1 IHC positive from negative pts. Thus, in addition to PD-L1 IHC, the predictive value of IFNG should be investigated in additional relevant studies
Selection CriteriaPrevalence of Biomarker Positive BiomarkerPositive/negative median OSlog-rank pHRcox pTC+158/276 (57%)15.67/7.730.00910.690.046TC+/IC+70/276 (25%)25.63/8.377.46E-060.345.24E-05TC+/IC-88/276 (32%)10.5/13.970.0941.50.032TC-/IC+50/276 (18%)9.07/13.230.830.960.84TC-/IC-68/276 (25%)5.77/14.030.000841.660.012
All comers: median OS: 11.2 months (N=304)
Citation Format: Carlos Bais, Chris Morehouse, Brandon W. Higgs, Rebelatto Marlon, Keith Steele, Xiaoping Jin, Li Shi, Susana Korolevich, Ashok Gupta, Koustubh Ranade. Biological and clinical relevance of PD-L1 expression in tumor and inflammatory cells in NSCLC [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 3720. doi:10.1158/1538-7445.AM2017-3720
Abstract 3722: In vitro induced regulatory T cells for understanding the nature of peripherally induced regulatory cells in relation to cell mediated immunotherapy for cancer
Authors: Hegde Upendra P. , Chakraborty Nitya G. 
Published: July 2017

Abstract
Background: pTregs are appearing to be one of the major obstacles of cellular immunotherapy of cancer. Tumor specific in vivo induced Cytotoxic T lymphocytes (CTL) are rapidly eliminated with concomitant expansion of pTreg cells. In human melanoma in ex vivo condition, tumor antigen specific CTL generated with CD8+ cells persisted for months while ex vivo induced CTL with whole PBL stimulated with Mart-127-35 A2 (tumor antigen) pulsed autologousDC, died within three weeks. Whereas Influenza (Flu 58-66) antigen specific CTL continued to expand and remained functional beyond four weeks.
Method: Peripheral blood and tumors were obtained from patients diagnosed with metastatic melanoma after informed consent. Blood derived dendritic cells, PBL, CD4+ and CD8+ cells were isolated for in vitro co-cultures with Mart-1 or Flu peptide pulsed autologous DC or autologous tumor cells. CD8+ CTL response and CD4+ positive Treg responses were measured. Freshly obtained tumor tissue derived lymphocytes (TIL) were also used for the study.
Results: Our results show that CTL response against Flu survived longer in culture with total PBL than CTL response against Mart-1 in identical culture conditions. CTL response using autologous tumor cells with PBL in culture lasted for a shorter duration but growth of Treg cells were observed. Cytokine analysis with expanding Treg cells showed secretion of IL-10 upon re-stimulation with autologous DC or anti-CD3 ab. Similarly, CD4+ cells isolated from freshly obtained tumor tissue (TIL, representing in vivo condition), suppressed T cell activation and secreted high amount of IL-10 upon re-stimulation.
Conclusion: These findings suggested that in vitro induced iTreg from cultures or pTreg from TILs (in vivo), work identical way, to negatively regulate effector immune response by secreting IL-10. Further analysis with iTregs for their use of metabolic pathways would be important to identify the specific signaling molecules used by autologous (person specific) pTregs , as target molecules, to block the expansion of such pTregs for the better outcome for CTL mediated immunotherapy for cancer.
Citation Format: Upendra P. Hegde, Nitya G. Chakraborty. In vitro induced regulatory T cells for understanding the nature of peripherally induced regulatory cells in relation to cell mediated immunotherapy for 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 3722. doi:10.1158/1538-7445.AM2017-3722
Abstract 3724: PDL1 protein expression and tumor mutation burden in hematologic malignancies: correlation with Hodgkin and high grade lymphoma
Authors: Karim Lina Abdul , Wang Peng , Guzman Jose de , Higgins Brandi , Chahine Joeffrey , Sheehan Christine , Kallakury Bhaskar , Ross Jeffrey S. 
Published: July 2017

Abstract
Background: The success of anti PD–1 therapy in Hodgkin lymphoma has led to clinical trials in other types of lymphomas. However, there is limited data on PD–L1 expression in acute leukemias. In this study, we analyzed PD–L1 protein expression and tumor mutational burden in various hematologic malignancies including leukemias, lymphomas and myelomas.
Methods: In the IHC cohort, formalin fixed paraffin embedded sections from 92 hematologic malignancies including acute myeloid and lymphoblastic leukemia (AML, ALL), Hodgkin lymphoma (HL), diffuse large B-cell lymphoma (DLBCL), low-grade non-Hodgkin lymphoma (LGNHL) and myeloma were immunostained using the FDA approved PD-L1 IHC 22C3 pharmDx assay [monoclonal mouse anti-PD–L1 antibody (DAKO clone 22C3)]. Any perceptible partial or complete membrane staining in all viable tumor cells was scored as follows: &lt;1%-negative, 1-49%-low level and &gt;50%-high level PD-L1 expression. In the second cohort of 2064 cases, comprehensive genomic profiling (CGP) was performed using a hybrid–capture, adaptor ligation assay to a mean depth of &gt;672X. Tumor mutation burden (TMB) was calculated from a minimum of 1.11MB of sequenced DNA as previously described and reported as mutations/MB.
High PD–L1 expression was noted in 100% of HL. DLBCL showed significantly higher PD–L1 positivity compared to LGNHL (p=0.01). No correlation for PD–L1 expression was noted between AML and ALL (p = 0.2). On CGP analysis of the second cohort, TMB was significantly higher in DLBCL as compared to LGNHL (p&lt;0.0001).
Conclusion: The high PD-L1 expression in both HL and DLBCL and high TMB in DLBCL may be linked to enhanced responsiveness to check point inhibitor therapy in these cancers. PD-L1 expression and TMB are relatively infrequent and at low levels in acute leukemias. Additionally, novel anti PD–1/PD–L1 therapeutic strategies are worthy of consideration for both advanced stage refractory/relapsed acute myeloid and lymphoblastic leukemias.
Results: PD-L1 expression and TMB are tabulated below.PD-L1 IHCTMB (mutations/MB)Tumor typenLow PositiveHigh PositiveTotal Positive (%)n&gt;=10.0&gt;=20.0AML21505/21 (24%)50%0%ALL3212012/32 (38%)10%0%HL1001010/10 (100%)368%8%DLBCL10448/10 (80%)25344%15%LGNHL10202/10 (20%)930%0%Myeloma9202/9 (22%)NANANA
Citation Format: Lina Abdul Karim, Peng Wang, Jose de Guzman, Brandi Higgins, Joeffrey Chahine, Christine Sheehan, Bhaskar Kallakury, Jeffrey S. Ross. PDL1 protein expression and tumor mutation burden in hematologic malignancies: correlation with Hodgkin and high grade lymphoma [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 3724. doi:10.1158/1538-7445.AM2017-3724
Abstract 3735: Detection of microsatellite instable colorectal cancers from routine NGS panel sequencing data
Authors: Endris Volker , Kirchner Martina , Kloor Matthias , Volckmar Anna-Lena , Doeberitz Magnus von Knebel , Penzel Roland , Schirmacher Peter , Stenzinger Albrecht 
Published: July 2017

Abstract
Introduction
In about 15% of all colorectal cancers, microsatellite instability (MSI) caused by defects in the DNA mismatch repair machinery can be detected. MSI driven tumors have a better prognosis compared to microsatellite stable (MSS) tumors and show good response to drugs targeting the PD-1-PD-L1 axis. Current molecular diagnostic procedures for colorectal cancer are primarily focused on the detection of oncogenic mutations in RAS family genes by either classical Sanger sequencing or next-generation sequencing. Routine testingof MSI status for therapeutic purposes is still rare and usually carried out by a different array of methods including PCR and immunohistochemistry.
Experimental procedures
In our routine diagnostic CRC screening, we sequenced more than 600 colorectal tumors with an entity specific customized 180 amplicon NGS panel encompassing HotSpot regions of 31 genes. This panel includes several homopolymeric regions of genes that are known to be affected by MSI. We retrospectively analysed this data set for MSI signatures, including deletion/insertion mutations in 20 different homopolymeric regions (&gt;7) and mutations/deletions of MLH1, MSH3, MSH6 and TGFBR2. Cases with an MSI signature detected by panel sequencing were reevaluated by PCR-based screening (Bethesda panel).
Results
From the 20 homopolymeric regions analyzed, several loci showed deletion/insertion mutations in MSI-positive patients. The highest discriminatory power presented a homopolymeric region within the ACVR2A gene showing a high analytical sensitivity and specificity towards MSI prediction. In combination with the readout of additional homopolymeric regions and the mutation status of MLH1, MSH3, MSH6 and TGFBR2, a sensitive and specific detection algorithm for MSI can be obtained from routine panel sequencing data. In conclusion, using only one assay, this approach facilitates simultaneous detection of mutations in RAS genes (and other druggable targets) and the MSI status in CRC As the assay is tissue sparing and time saving it may be advantageous over classic test approaches that are currently being employed in routine diagnostics.
Note: This abstract was not presented at the meeting.
Citation Format: Volker Endris, Martina Kirchner, Matthias Kloor, Anna-Lena Volckmar, Magnus von Knebel Doeberitz, Roland Penzel, Peter Schirmacher, Albrecht Stenzinger. Detection of microsatellite instable colorectal cancers from routine NGS panel sequencing data [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 3735. doi:10.1158/1538-7445.AM2017-3735