bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 532: Irradiation alters the tumor microenvironment of orthotropic pancreatic tumor in favoring the infiltration of PD1+CD8 and G-MDSC and the delivery of immune checkpoint blockade therapy agents
Authors: Lee Yu Hung
Published: August 2019

Immunotherapy (IT) is trending on cancer research, but its efficacy heavily depends on the tumor microenvironment (TME). IT is also frequently combined with radiation therapy (RT). Here, we explored the effect of radiation therapy (RT) on the TME and its consequence on the combination of IT using a syngeneic orthotropic UN-KC6141 PDAC tumor model. The result of immunohistochemical staining (IHC) demonstrates that 25Gy of IR could effectively decrease the number of CD31+ vessels, but significantly increase distribution area of Dextran, an indication of vessel normalization. The normalized tumor vessels are more effectively on delivering ICBT (immune checkpoint blockade therapy) drug delivery as shown by the increase of anti-PD-L1 antibody in irradiated tumor. In addition, we also found that the number of PD1+CD8+ Tc cells and Ly6G+G-MDSC is also increased in irradiated tumor. This indicates that RT could alter TME of pancreatic tumor in favoring the combination with IT, not only alters an immune desert tumor to become an immune infiltrating tumor, but also enhances the delivery of ICBT agents. For this tumor model, the combination of RT with anti-PD-L1 or anti-Ly6G therapy could be effective. To test this hypothesis, the combination of RT with ICBT agents was performed. The preliminary results show that anti-PD-L1 ICBT could enhance the efficacy of RT on decreasing tumor burden. The combination of anit-Ly6G therapy with RT is currently under investigation.

Citation Format: Yu Hung Lee. Irradiation alters the tumor microenvironment of orthotropic pancreatic tumor in favoring the infiltration of PD1+CD8 and G-MDSC and the delivery of immune checkpoint blockade therapy agents [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 532.
Abstract 537: Antibody drug conjugate to treat triple negative breast cancer
Authors: Si Yingnan , Dang Nghi , Kim Seulhee , Zhou Lufang , Han Xiaosi , Liu Runhua , Liu Xiaoguang (Margaret)
Published: August 2019

Triple negative breast cancer (TNBC) is characterized by rapid growth, metastasis, and high recurrence. The severe adverse effects and drug resistance associated with standard cytotoxic chemotherapies minimize their clinical benefits. The anti-epidermal growth factor receptor (EGFR) monoclonal antibody (mAb) had been developed and tested to treat TNBC, but no significant efficiency was demonstrated in clinical trials. The goal of this study was to develop a novel antibody-drug conjugate (ADC) to treat TNBC. Specifically, we established a platform to conjugate anti EGFR mAb with mertansine, which inhibits cell division by blocking tubulin polymerization, and also improved the conjugation efficiency by optimizing the linker and drug-to-antibody ratio. Flow cytometry and live cell confocal laser scanning microscopy analysis confirmed that the anti-EGFR ADC can specifically bind to multiple TNBC subtypes, is effectively internalized, and release potent drug intracellularly within 1 hour after mixing. The IC50 study showed that the anti-EGFR ADC killed >90% TNBC cells with dose of 5 nM. The TNBC xenograft mouse model also showed that the constructed ADC had high anticancer efficacy and successfully inhibited tumor growth. Moreover, the live-animal imaging using In Vivo Imaging System and the tissue microarray samples with immunohistochemical analysis of TNBC and organs indicated that our ADC specifically target TNBC in vivo. Further evaluations, such as maximal tolerated dose (MTD), pharmacokinetics (PK), and biodistribution, are needed. To summarize, we developed an EGFR-targeted ADC, which could provide an effective targeted therapy to treat TNBC and improve the life quality and survival rate of patients with TNBC.

Note: This abstract was not presented at the meeting.

Citation Format: Yingnan Si, Nghi Dang, Seulhee Kim, Lufang Zhou, Xiaosi Han, Runhua Liu, Xiaoguang (Margaret) Liu. Antibody drug conjugate to treat triple negative breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 537.
Abstract 54: Characterization of patient-derived organoids cultured on a gas-rich, liquid-liquid interface
Authors: Shoemaker James T. , Richardson Katherine R. , Arnst Jamie , Marcus Adam , Vukasinovic Jelena
Published: August 2019

Modeling tissues in vitro has long consisted of two-dimensional (2D) monolayer cultures grown in a dish, flask, or multi-well plate. While these methods remain adequate for some applications, the advent of personalized cancer therapies has necessitated the development of more complex models that more accurately represent the in vivo environment. Attempting to characterize tumor cell biology and response to candidate pharmaceuticals in 2D cultures has led to results that fail to translate to clinical therapies. A key source of this failure is the loss of cell diversity due to selective pressure resulting in cell populations that favor adhering to a rigid substrate. Three-dimensional (3D) cell culture methods have produced models that capture many of the dynamics of the in vivo tissue environment. Patient-derived organoids (PDOs) are quickly becoming the most attractive solution for creating predictive, patient-specific tumor models in vitro. Typically grown as spheroids, these models still present limitations in terms of cell survival and recapitulation of tumor development.

Lena Biosciences has previously developed complex, vascularized tissue models using patented 3D scaffolds and a perfusion system. Hepatocytes grown in this system demonstrated increased cell viability and recovery of cytochrome P450 enzyme activity compared to 2D controls. Integral to the perfusion system is a pure, synthetic liquid that is twice as dense as and immiscible with cell culture medium and reagents. It is permissive to atmospheric gases, providing a gas-rich, liquid-liquid interface below 3D cultures maintained in the system. We hypothesized that PDOs could be cultured without a 3D scaffold, directly at the interface between the cell culture medium and this synthetic liquid. A specific preparation of this interface resulted in lung-derived PDOs that spontaneously formed dense, 3D, tissue-like structures that showed increased viability (as measured by a 50% reduction in LDH release) and cellular respiration (three-fold increase as measured by an alamarBlue assay). Ongoing studies are focused on characterizing PDOs from other patients and other tissues as they develop in long-term in vitro studies. Should this PDO model prove to be a faithful representation of in vivo tumor development, this system would be ideal for applications such as testing drug efficacy and studying mechanisms of tumor metastasis.

Citation Format: James T. Shoemaker, Katherine R. Richardson, Jamie Arnst, Adam Marcus, Jelena Vukasinovic. Characterization of patient-derived organoids cultured on a gas-rich, liquid-liquid interface [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 54.
Abstract 550: Tumor-conditional anti-CTLA-4 uncouples anti-tumor efficacy from immunotherapy-related toxicity
Authors: Pai Steven C. , Simons Donald M. , Lu Xiaoqing , Ritacco Wendy , Evans Michael , Kingsbury Gillian , Fong Lawrence
Published: August 2019

While immune checkpoint blockade leads to potent anti-tumor efficacy, it also leads to immune-related adverse events in cancer patients. These toxicities stem from systemic immune activation resulting in multi-organ inflammation including the gastrointestinal tract, lung, and endocrine organs. We developed a dual variable domain immunoglobulin of anti-CTLA-4 antibody (anti-CTLA-4 DVD) possessing an outer tumor-specific antigen-binding site engineered to shield the inner anti-CTLA-4 binding domain. Upon reaching the tumor, the outer domain is cleaved by membrane type-serine protease 1 (MT-SP1) present in the tumor microenvironment, leading to enhanced localization of CTLA-4 blockade. Anti-CTLA-4 DVD significantly reduced multi-organ immune toxicity by preserving tissue-resident regulatory T cells (Tregs) in Rag 1-/- mice that received naïve donor CD4+ T cells from wild-type C57BL/6j mice. Moreover, anti-CTLA-4 DVD induced potent antitumor effects by decreasing tumor-infiltrating Tregs and increasing the infiltration of antigen-specific CD8+ T lymphocytes in TRAMP-C2 bearing C57BL/6j mice. Tregs depletion was mediated through the antibody-dependent cellular cytotoxicity (ADCC) mechanism, as anti-CTLA-4 without the FcγR binding portion (anti-CTLA-4 DANA) spared Tregs, preventing treatment-induced toxicities. In summary, our results demonstrated a new approach to anti-CTLA-4 blockade that depletes tumor-infiltrating, but not tissue-resident Tregs, preserving anti-tumor effects while minimizing toxicity. Thus, our tumor-conditional anti-CTLA-4 DVD provides an avenue to uncouple anti-tumor efficacy from immunotherapy-induced toxicities.

Citation Format: Steven C. Pai, Donald M. Simons, Xiaoqing Lu, Wendy Ritacco, Michael Evans, Gillian Kingsbury, Lawrence Fong. Tumor-conditional anti-CTLA-4 uncouples anti-tumor efficacy from immunotherapy-related toxicity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 550.
Abstract 565: A novel T-cell costimulatory Humabody® VH therapeutic for PSMA-positive tumors
Authors: Legg James W. , McGuinness Brian , Archer Sophie , Bland-Ward Phil , Brucklacher Verena , Craigen Jenny , Edwards Carolyn , Hames Emma , Majithiya Jay , Pisa pavel , Revi Bhindu , Royale Nikki , Sette Angelica , Teng Yumin , Thompson Lorraine , Wang Wembin , Wilson Chris , Wyre Chris , Rossant Chris
Published: August 2019

Agonistic monoclonal antibodies targeting CD137/4-1BB have shown much preclinical promise but their clinical development has been slowed due to a poor therapeutic index, in particular liver toxicity. CB307 is a novel half-life extended bispecific Humabody VH targeting CD137 (4-1BB) and prostate specific membrane antigen (PSMA). The design of CB307 enables agonism of CD137 selectively in the presence of PSMA positive tumour cells and in this way enable tumour selective T cell activation whilst minimising systemic activation. The molecular weight of CB307 is less than 50 kDa (around a third of the size of a standard IgG) and it does not contain an Fc domain, thereby avoiding interaction with Fc receptors. Half life extension is achieved through the inclusion of a VH domain with specificity for human serum albumin (HSA). The identification of CB307 using the Crescendo Mouse™ which develops fully human VH domains in a background devoid of light chains will be described along with characterisation of the key properties of the molecule in in vitro and in vivo models. In dual target binding assays CB307 shows potent co-binding to both PSMA and CD137 targets and mediates CD137 signalling in an NFKB cell reporter assay in the presence of PSMA positive cells but not PSMA negative cells. Co-incubation of primary human T-cells from healthy individuals or cancer patients together with PSMA positive tumour cells and CD3 stimulation induces T-cell activation and cytokine release. In an in vivo model using NSG mice engrafted with human PBMCs the growth of PSMA positive DU145 prostate tumour cells is inhibited by a surrogate bispecific. Together these data support progression of CB307 into clinical development.

Citation Format: James W. Legg, Brian McGuinness, Sophie Archer, Phil Bland-Ward, Verena Brucklacher, Jenny Craigen, Carolyn Edwards, Emma Hames, Jay Majithiya, pavel Pisa, Bhindu Revi, Nikki Royale, Angelica Sette, Yumin Teng, Lorraine Thompson, Wembin Wang, Chris Wilson, Chris Wyre, Chris Rossant. A novel T-cell costimulatory Humabody® VH therapeutic for PSMA-positive tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 565.
Abstract 573: Mutations found by targeted next generation sequencing is associated with intra-tumor immune profile and may predict response to anti-PD1 therapy in lung adenocarcinoma
Authors: Lupo Audrey , Biton Jerome , Alifano Marco , Damotte Diane , Arrondeau Jennifer , Boudou Pascaline , Goldwasser François , Leroy Karen , Wislez Marie , Laurent-Puig Pierre , Cremer Isabelle , Blons Helène , Herbst Ronald
Published: August 2019

Purpose: the immune environment of cancer is the target of immunotherapies with programmed cell death 1 (PD-1) therapeutic antibodies. However, factors that can robustly predict long-lasting responses are still needed. Previous studies showed a role of cancer cells on immune response setting, but the impact of somatic mutations on the composition of the immune stroma is not fully characterized.

Experimental Design: We characterized the immune profile of 221 lung adenocarcinomas using immunohistochemistry (CD8 T cells, Macrophages, neutrophils, PD-L1) and compare to tumor mutational status using targeted next-generation sequencing. The response to PD-1 blockers was analyzed from a prospective cohort of 31 lung carcinomas according to tumor mutational profiles and to tumor cell PD-L1 expression.

Results: We report that distinct combinations of STK11, EGFR and TP53 mutations, allows the identification of immune cells combination and prediction of PD-L1 expression on tumor cells. Lung adenocarcinomas with the highest CD8 T cell density and PD-L1 expression were those with TP53 mutations without co-occurring STK11or EGFR alterations (TP53-mut/STK11-EGFR-WT), and independently of KRAS status. Interestingly in TP53-mut/STK11-EGFR-WT tumors, pathways related to T cell chemotaxis, immune cell cytotoxicity, and antigen processing were up-regulated. In accordance with these results we found a prolonged progression-free survival (PFS: HR=0.32; 95% CI, 0.16-0.63, p<0.001) in anti-PD-1 treated patients harboring TP53-mut/STK11-EGFR-WT tumors. This clinical benefit was even more remarkable in patients with associated strong PD-L1 expression.

Conclusions: Our study reveals that mutations in lung adenocarcinoma impact intra-tumor immune profile and predict response to PD-1 blockade.

Citation Format: Audrey Lupo, Jerome Biton, Marco Alifano, Diane Damotte, Jennifer Arrondeau, Pascaline Boudou, François Goldwasser, Karen Leroy, Marie Wislez, Pierre Laurent-Puig, Isabelle Cremer, Helène Blons, Ronald Herbst. Mutations found by targeted next generation sequencing is associated with intra-tumor immune profile and may predict response to anti-PD1 therapy in lung adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 573.
Abstract 575: Adaptive CD4 Th1 response against telomerase in blood counteracts T-cell exhaustion in non-small cell lung cancer
Authors: Laheurte Caroline , Dosset Magalie , Vernerey Dewi , Joseph Elodie Lauret Marie , Boullerot Laura , Kaulec Vincent , Jacquin Marion , Cuche Laurie , Eberst Guillaume , Jacoulet Pascale , Westeel Virginie , Adotevi Olivier
Published: August 2019

Despite the critical roles played by IFN-γ+ CD4 Th1 response in tumor immunity, the translation of their potential in clinic remains challenging. Here, we evaluate the clinical significance of circulating anti-tumor CD4 Th1 response in non-small cell lung cancer (NSCLC) patients. 170 naïve-treatment patients were enrolled in this immune monitoring study. The antitumor adaptive Th1 response was assessed by IFN-γ ELISPOT assay in blood lymphocytes using a mixture of eight highly promiscuous and Th1-polarized HLA class II-restricted epitopes from telomerase (TERT). The presence of anti-TERT Th1 response was detected in 59/170 patients (35%). We found an opposite link between anti-TERT Th1 and hyper exhausted T cells co-expressing PD-1+ and TIM-3+ in NSCLC patients. In contrast to hyper exhausted CD8 T cells, the presence of anti-TERT Th1 response was associated with a low rate of hyper exhausted CD4 T cells. We showed that NSCLC stage dissemination is associated with a decrease of anti-TERT Th1 response but an increase of circulating hyper exhausted PD-1+/TIM-3+ CD4 T cells. Notably, anti-telomerase Th1 response and hyper exhausted CD4 T-cells displayed opposite prognosis value in NSCLC. While high level of anti-TERT Th1 cells play a protective role, hyper-exhausted PD-1+TIM-3+ CD4 T cells negatively affect patients’ survival. By using these two circulating immune factors, we stratified patients in distinct prognostic group. Patients with anti-TERT Th1high/CD4 PD-1 TIM-3low immune profile had better overall survival than anti-TERT Th1low/CD4 PD-1 TIM-3high group (median OS : not reached versus 4 months respectively p<0.0001). In conclusion, high circulating anti-TERT Th1 response plays a strong protective role in NSCLC by counteracting the deleterious effect associated with hyper exhausted T cells in blood. Our study provides a dynamic blood-based immunomonitoring tool allow patients stratification.

Citation Format: Caroline Laheurte, Magalie Dosset, Dewi Vernerey, Elodie Lauret Marie Joseph, Laura Boullerot, Vincent Kaulec, Marion Jacquin, Laurie Cuche, Guillaume Eberst, Pascale Jacoulet, Virginie Westeel, Olivier Adotevi. Adaptive CD4 Th1 response against telomerase in blood counteracts T-cell exhaustion in non-small cell lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 575.
Abstract 578: Investigation of the effect of hypoxia on presentation of HPV16-derived antigens - implications for therapeutic vaccine design
Authors: Mohan Nitya , Bonsack Maria , Förster Jonas , Steinbach Alina , Blatnik Renata , Salek Mogjiborahman , Riemer Angelika B.
Published: August 2019

Human papillomavirus type 16 (HPV16) is a causal factor of ~50% of cervical cancers, and of ~95% of extra-cervical (other anogenital and oropharyngeal) HPV-mediated cancers. The aim of our group is to develop a therapeutic vaccine against HPV16-induced malignancies. To find optimal vaccine antigens, it is important to assess the effect of the tumor microenvironment on viral antigen presentation. Hypoxia has been reported to regulate HLA class-I expression levels in the context of various tumors. Thus, the aim of the present study was to explore the effect of hypoxia on various components of the antigen processing machinery (APM) in HPV16-positive tumor cells and on the HPV16 E6- and E7-derived HLA class-I epitope repertoire. We are investigating the effect of hypoxia on cervical cancer cells transformed with HPV16 variant lineages (European, Asian-American and African) correlated with differences in oncogenic potential. This is achieved by comparing cells cultured under hypoxia (1.2% O2) or normoxia (21% O2). We investigate E6 protein levels by immunoblotting and HLA-A2 surface expression by flow cytometry. Subsequently, quantitative PCR and immunoblotting are used to assess whether components of the APM are affected by hypoxia. Cervical cancer cell lines transformed by sublineages of the HPV16 European variant (CaSki and SNU17) showed a decrease in E6 protein levels upon hypoxic treatment. HLA-A2 levels were increased in SNU17 cells (HPV16 European Asian prototype), but no change was observed in CaSki cells (European Prototype 2). First qPCR experiments of SNU17 cells showed changes in additional components of the APM at the mRNA level, which still have to be assessed at the protein level. Cell lines transformed by HPV16 variants other than European will be subjected to the same analysis. Potential changes in the HPV16 epitope repertoire will be investigated using a targeted mass spectrometry-based epitope detection strategy established in the lab. These investigations may yield novel insights into HPV16 immune evasion pathways. Furthermore, the identification of epitopes that are presented under both normoxic and hypoxic conditions will provide optimal candidates for therapeutic vaccine design against HPV-induced malignancies.

Citation Format: Nitya Mohan, Maria Bonsack, Jonas Förster, Alina Steinbach, Renata Blatnik, Mogjiborahman Salek, Angelika B. Riemer. Investigation of the effect of hypoxia on presentation of HPV16-derived antigens - implications for therapeutic vaccine design [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 578.
Abstract 597: Occupational exposure to diesel engine exhaust and alternations in serum microRNAs
Authors: Hu Wei , Bassig Bryan A. , Dai Yufei , Ren Dianzhi , Duan Huawei , Niu Yong , Xu Jun , Fu Wei , Meliefste Kees , Zhou Baosen , Yang Jufang , Ye Meng , Jia Xiaowei , Meng Tao , Bin Ping , Wong Jason YY , Hosgood Dean H. , Rothman Nathaniel , Vermeulen Roel C. , Silverman Debra T. , Zheng Yuxin , Lan Qing
Published: August 2019

Diesel engine exhaust (DEE) is a known lung carcinogen and may be associated with other tumors, however, the mechanisms of action by which DEE causes cancer is not well understood. MicroRNAs (miRNAs), which are small non-coding RNA molecules that play a role in post-transcriptional regulation of gene expression, are altered in multiple tumors and have been observed to be differentially expressed in a variety of biospecimen types in smokers as well as in relation to short-term air pollution exposure. To evaluate whether serum levels of miRNAs are altered in healthy workers occupationally exposed to DEE, we analyzed samples collected in a cross-sectional molecular epidemiology study of diesel engine truck testing facility workers and comparable unexposed controls in China. A panel of 44 miRNAs were measured in 46 workers exposed to relatively high air levels of DEE and 45 controls using the Fireplex circulating miRNA assay (Abcam, Inc.), which profiles miRNAs directly from biofluids. The exposure-response relationship between categorical EC levels and each miRNA was analyzed by linear regression adjusted for age, body mass index, smoking status, current alcohol use and recent infection. We identified two miRNAs that showed a monotonic inverse exposure-response association with DEE: miR-191-5p and miR-93-5p. Levels of miR-191-5p in arbitrary units (A.U.) of fluorescence were 400.7, 333.0, 322.6, and 260.0 in controls and across increasing tertiles of EC, respectively (p for trend = 0.001, FDR = 0.05). Levels of miR-93-5p were 747.1, 713.7, 720.5, and 625.4 A.U. in controls and increasing tertiles of EC, respectively (p for trend = 0.008, FDR = 0.18). Both miRNAs have been reported to influence several biological processes important in carcinogenesis. Our results suggest that occupational exposure to DEE may affect circulating miRNAs in healthy workers.

Citation Format: Wei Hu, Bryan A. Bassig, Yufei Dai, Dianzhi Ren, Huawei Duan, Yong Niu, Jun Xu, Wei Fu, Kees Meliefste, Baosen Zhou, Jufang Yang, Meng Ye, Xiaowei Jia, Tao Meng, Ping Bin, Jason YY Wong, Dean H. Hosgood, Nathaniel Rothman, Roel C. Vermeulen, Debra T. Silverman, Yuxin Zheng, Qing Lan. Occupational exposure to diesel engine exhaust and alternations in serum microRNAs [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 597.
Abstract 599: Smoking-associated AHRR demethylation in cord blood DNA: Impact of CD235a+ nucleated red blood cells
Authors: Bergens Matthew A. , Pittman Gary S. , Thompson Isabel J. , Campbell Michelle R. , Wang Xuting , Wan Ma , Hoyo Cathrine , Bell Douglas A.
Published: August 2019

Prenatal tobacco smoke exposure is associated with numerous adverse health outcomes at birth and in later life. Numerous studies have demonstrated that Aryl Hydrocarbon Receptor Repressor gene (AHRR) hypomethylation in umbilical cord blood is significantly associated with prenatal tobacco smoke exposure and is suitable as a fetal exposure biomarker. The mechanism driving this demethylation and whether all cord blood cell types are impacted is unclear. Nucleated red blood cells (nucleated CD235a+ cells, nRBCs) are developmentally immature RBCs that display genome-wide demethylation and are observed at increased frequency in the cord blood of smoking mothers. We assessed if nRBC counts or methylation level affected smoking-associated DNA methylation in the AHRR gene as measured in whole cord blood. We analyzed methylation in DNA from whole cord blood, CD14+ monocytes, and nRBCs across four AHRR CpGs using pyrosequencing and also with Illumina 850K arrays (cg05575921) from smoking (n=34) and nonsmoking (n=19) mothers. nRBCs present in cord blood were determined by conventional CBCs and also estimated with a Houseman deconvolution model. AHRR methylation levels were significantly lower in nRBCs relative to whole blood and CD14+ monocytes. Methylation values at each AHRR CpG averaged 14.6% lower in nRBCs (range 0.4% to 24%, p=3.9E-13) relative to CD14+ monocytes with nonsmokers displaying significantly greater hypomethylation in nRBCs than smokers. Methylation levels at each CpG across the AHRR DMR were strongly associated with either self-reported smoking or cord blood cotinine levels in both CD14+ monocytes (r2=0.45, p=4.6E-08) and nRBCs (r2=0.26, p=1.2E-04). The most significant prenatal smoking effect on methylation occurred in CD14+ monocytes at the CpG located at chr5:373490 (-16.7%, p=6.7E-09), 112nt downstream of cg05575921. For subjects with 850K data, adjusting a regression analysis model with estimated cell-type composition, including nRBC counts or estimates, marginally increased the magnitude and significance of the prenatal smoke exposure effect on AHRR cg05575921 methylation. Prenatal tobacco smoke exposure strongly affects DNA methylation in the AHRR gene and this prenatal smoke exposure biomarker is largely unaffected by cord blood cell type composition.

Citation Format: Matthew A. Bergens, Gary S. Pittman, Isabel J. Thompson, Michelle R. Campbell, Xuting Wang, Ma Wan, Cathrine Hoyo, Douglas A. Bell. Smoking-associated AHRR demethylation in cord blood DNA: Impact of CD235a+ nucleated red blood cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 599.
Abstract 6: Computationally assisted target screening of STING agonist for immunologic therapy
Authors: Binder Grace A. , Gambino Christine S. , Kharitonova Anna , Metcalf Rainer S. , Daniel Kenyon G. , Guida Wayne C.
Published: August 2019

Stimulator of interferon genes (STING) is a receptor protein involved in the propagation of innate immune sensing of cytosolic DNA through the production of IFN-β. Mechanistic studies have shown IFN-β production within the tumor microenvironment can result in activation of tumor antigen-specific CD8+ T-cell immunity that can lead to tumor regression [1, 2]. STING activation by STING agonists should result in innate T-cell mediated anti-tumor immunity in the tumor microenvironment and have significant potential as a cancer therapeutic. Conversely, inhibition of STING would lead to a decreased production of IFN-β which could have implications in the treatment of autoimmune disease such as lupus erythematosus.

MD equilibrated crystal structures for human HAQ, REF, and WT alleles were clustered to find optimal conformations for diverse chemical library screening. Novel consensus docking protocols utilizing rigid receptor, induced fit, and quantum polarized ligand docking were applied for quantifying and refining proposed binding mechanisms of STING isoforms. Models for STING agonists and antagonists were developed.

From directed virtual screening, a novel low-molecular-weight organic molecule (GF3-002) that is not based on a cyclic dinucleotide was found as a potential STING activator and is currently under investigation.

GF3-002 and analogs were synthesized and structures were confirmed with LCMS and proton NMR. Both the HAQ and WT alleles, representing 78.3% of the human population were tested against compounds and controls. 2,3-cGAMP and DMSO were used as positive and negative controls, respectively. Microscale thermophoresis and SPR confirmed binding of GF3-002 to WT STING CTD with a kD of 3.2 ± 1.7 μM. IFN-dependent luciferase expression was measured by luminescence in THP-1 monocytic leukemia cells and found an EC50 of 29 ± 1.6 μM, compared to the native ligand 2,3-cGAMP EC50 of 42 ± 4.1 μM. Finally, qPCR was used quantify production of IFN-β via treatment of dendritic cells with GF3-002.

1. Sali, Characterization of a Novel Human-Specific STING Agonist that Elicits Antiviral Activity Against Emerging Alphaviruses. 2017.

2. Corrales, L., et al., Direct activation of STING in the tumor microenvironment leads to potent and systemic tumor regression and immunity. Cell reports, 2015. 11(7): p. 1018-1030.

Citation Format: Grace A. Binder, Christine S. Gambino, Anna Kharitonova, Rainer S. Metcalf, Kenyon G. Daniel, Wayne C. Guida. Computationally assisted target screening of STING agonist for immunologic therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 6.
Abstract 633: Association between saturated fat intakes and lung cancer risk among low-income populations in the Southeastern United States
Authors: Yoon Hyung-Suk , Cai Hui , Yang Jae Jeong , Yu Danxia , Murff Harvey J. , Shu Xiao Ou , Zheng Wei , Blot William J. , Cai Qiuyin
Published: August 2019

Background: Lung cancer is the leading cause of cancer death in the United States. Previous studies have indicated that a higher intake of dietary saturated fat was associated with lung cancer risk. However, little is known about the association of specific classes of saturated fat with the risk of lung cancer. We conducted a nested case-control study to investigate the association of different classes of saturated fat with lung cancer risk among low-income African Americans (AAs) and European Americans (EAs) in the Southeastern United States.

Methods: A total of 1,528 incident lung cancer cases and 5,699 matched controls from the Southern Community Cohort Study were included in this study. The controls were matched to the cases on age, sex, race, and recruitment site. Using validated food frequency questionnaires, saturated fat was estimated and classed to short-chain (SCSF, 2-4 carbon atoms), medium-chain (MCSF, 6-12 carbon atoms), and long-chain (LCSF, 14-18 carbon atoms). Multivariate logistic regression models were used to estimate odds ratios (ORs) and corresponding confidence intervals (95% CIs) for lung cancer risk associated with saturated fat after adjusting for age, smoking status, pack-years, alcohol consumption, total energy intake, education, household income, body mass index (BMI), and history of chronic obstructive pulmonary disease (COPD).

Results: Total saturated fat intakes were associated with an increased lung cancer risk among EAs with an OR of 1.66 (95% CI: 1.06-2.60) for the highest vs. lowest quartiles (p-trend=0.03). The positive association was only observed for LCSF (highest vs. lowest quartile: OR=1.68, 95% CI: 1.07-2.64 for palmitic acid; OR=1.60, 95% CI 1.02-2.53 for stearic acid; and OR=1.63, 95% CI 1.04-2.56 for total LCSF; all p-trends<0.05). The association was more evident among heavy smokers, which was defined as smoke ≥ 30 pack-years, and for adenocarcinoma subtype. No association between saturated fat intakes with lung cancer risk were observed among AAs. In addition, no association between lung cancer risk and SCSF or MCSF was observed in our study.

Conclusion: Our findings indicate that a high intake of LCSF was associated with an increased risk of lung cancer among low-income EAs. Further studies are needed to confirm our findings.

Citation Format: Hyung-Suk Yoon, Hui Cai, Jae Jeong Yang, Danxia Yu, Harvey J. Murff, Xiao Ou Shu, Wei Zheng, William J. Blot, Qiuyin Cai. Association between saturated fat intakes and lung cancer risk among low-income populations in the Southeastern United States [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 633.
Abstract 648: Effects of bazedoxifene and lapatinib in the prevention of estrogen receptor positive (ER+) and negative (ER-) mammary cancers
Authors: Grubbs Clinton J. , Mohammed Altaf , Sei Shizuko , Shoemaker Robert H.
Published: August 2019

Bazedoxifene is a third-generation selective estrogen receptor modulator (SERM) that has been clinically approved in Europe for the prevention and treatment of postmenopausal osteoporosis. Our research previously showed that this agent (at a dose of 5 mg/kg diet) would decrease ER+ mammary cancers in rats by 73%. Lapatinib, an epidermal growth factor receptor (EGFR) inhibitor, is commonly used to treat patients with HER2+ breast cancer. We have also shown that the compound inhibits the development of ER+ mammary cancers in rats and ER- mammary cancers in mice at a dose of 75 mg/kg BW/day. The present studies were done to determine if lower doses and different treatment regimens designed to reduce possible toxicity would also be effective in preventing mammary cancers. Bazeodxifene was added directly to the diet (Teklad, 4% fat), while lapatinib was given by oral gavage. When evaluated in rats receiving methylnitrosourea (MNU), lapatinib given daily at doses of 75, 50 and 25 mg/kg BW/day reduced mammary cancer multiplicity by 93, 84 and 67%, respectively. Equivalent doses given 1x/week caused reductions of 87, 56, and 40%. When lapatinib was given to dimethylbenzanthracene (DMBA) treated MMTV/Neu mice at dose levels of 250, 125, and 63 mg/kg BW, 5x/week, mammary cancer multiplicity was reduced by 89, 60 and 80%, respectively. When equivalent doses were given 1x/week, the number of cancers were reduced by 82, 61, and 70%. Bazedoxifene given at 5.0 and 2.5 mg/kg diet to female MMTV/Neu mice also receiving DMBA caused reduction of mammary cancers by 73 and 51%. In a biomarker study lasting two weeks, bazedoxifene at the 5.0 mg/kg BW/day dose decreased the proliferation rate of normal mammary epithelial cells in MMTV/Neu mice by 60%. Additional studies to determine why this SERM is having a preventive effect against ER- mammary cancers are warranted. Studies to evaluate the efficacy of the combination of low doses of bazedoxifene and lapatinib in prevention of ER+ and ER- mammary cancers are in progress and will be presented.

Supported by the NCI contract number HHSN261201500036I, Task Order HHSN26100005.

Citation Format: Clinton J. Grubbs, Altaf Mohammed, Shizuko Sei, Robert H. Shoemaker. Effects of bazedoxifene and lapatinib in the prevention of estrogen receptor positive (ER+) and negative (ER-) mammary cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 648.
Abstract 667: A mouse model of APOE to define effects of doxorubicin on cognition
Authors: Demby Tamar C. , Lee Yichien , Rodriguez Olga , Albanese Christopher , Mandelblatt Jeanne , Rebeck G. William
Published: August 2019

The purpose of this study was to establish the effects of Apolipoprotein E (APOE) genotype on cognitive function following doxorubicin treatment in a mouse model. Chemotherapy treatment can lead to cognitive impairment in cancer survivors, and, in older breast cancer survivors, APOE4 carriers have been shown to have higher risk for these impairments. Though APOE4 genotype is known as the strongest genetic risk factor for late-onset Alzheimer’s Disease compared to the APOE2 and APOE3 alleles, its effects on cognitive outcomes following treatment with common breast cancer chemotherapeutics are not yet well characterized. One year old female mice with targeted replacement of human APOE3 or APOE4 under control of the endogenous murine promoter were treated with 10 mg/kg doxorubicin or saline. Five weeks following treatment, spatial learning and memory was tested using the Barnes Maze. In APOE3 mice, doxorubicin treatment left spatial learning and memory intact. In APOE4 mice, doxorubicin treatment lead to impairment in spatial learning over the four days of training. This represents a promising model for studying the mechanisms behind cognitive impairment following doxorubicin treatment in a genetically vulnerable population.

Citation Format: Tamar C. Demby, Yichien Lee, Olga Rodriguez, Christopher Albanese, Jeanne Mandelblatt, G. William Rebeck. A mouse model of APOE to define effects of doxorubicin on cognition [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 667.
Abstract 674: Predicting cellular response to therapy in breast cancer using mathematical modeling
Authors: He Wei , Demas Diane M. , Conde Isabel , Fallah Yassi , Baumann William T. , Shajahan-Haq Ayesha N.
Published: August 2019

About 70% of all breast cancer tumors are estrogen receptor positive (ER+) and are treated with antiestrogen therapies. While the inevitability of developing resistance to these therapies remains uncontested, little is known about the mechanism and prevention of resistance. Our ultimate goal is to use mathematical modeling to optimize dynamic therapies that decrease proliferation and stave off resistance. In this initial study, we used MCF7 cells as a model of ER+ breast cancer and estrogen deprivation as a surrogate for aromatase inhibitors. We developed long-term estrogen deprived MCF7s (LTEDs) that proliferate similarly to untreated MCF7s but are resistant to antiestrogens. We collected time-course data for simultaneous gene expression and protein levels (NanoString Pan Cancer panel, a non-amplification based digital method) over 6 weeks to capture early molecular adaptations of deprived MCF7s and compare them to those present in LTEDs. PCA analysis of the mRNA and protein data shows a dramatic change in the first component due to estrogen deprivation, and a dramatic change in the second component associated with long-term resistance. Correlation analysis shows a large number of cell cycle genes that are similarly regulated, decreasing with estrogen deprivation and increasing with the onset of resistance. There is also a highly-correlated group of genes associated with resistance. This knowledge allowed us to hypothesize a molecular mechanism for resistance that can be tested experimentally. To begin building a dynamic model, we measured a 7-day time course of estrogen related proteins. The model is built around ER signaling and the cell cycle, and simulates protein and proliferation changes in response to deprivation and antiestrogen (ICI182,780; ICI) treatment. To determine which treatments to model in addition to estrogen deprivation and ICI, we looked for a promising sequential therapy to limit proliferation and, hopefully, stave off resistance compared to a single non-stop therapy. We found that alternating the targeting of CDK4/6 using Palbociclib (clinical anti-cancer therapy) with targeting of RUNX1 (gene that is increased at the onset of resistance in our model), could be a plausible strategy to inhibit endocrine resistance. Future work will involve extending the model to longer time scales and using it for treatment optimization.

Citation Format: Wei He, Diane M. Demas, Isabel Conde, Yassi Fallah, William T. Baumann, Ayesha N. Shajahan-Haq. Predicting cellular response to therapy in breast cancer using mathematical modeling [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 674.
Abstract 685: Development of a multiscale QSP model to characterize the tumor suppressive effects of a cytokine mRNA immunotherapy in a preclinical melanoma mouse model
Authors: Pierre Kamau , Lin Lin , Gruenbaum Lore , Young Carissa , Apgar Joshua , Hotz Christian , Wagenaar Timothy , Stamatelos Spyros K.
Published: August 2019

Despite the success of checkpoint blockade immunotherapy, most patients do not respond adequately to treatment and tumors effectively evade T lymphocyte and Natural Killer (NK) cell immune surveillance. Within the tumor microenvironment, the activities of immune cells are regulated by a multitude of signals including the local cytokine milieu. Intratumoral administration of our cytokine mRNA cocktail therapy, consisting of transcripts encoding for IL-12sc, IFNα2b, IL-15sushi and GM-CSF, has induced regression in tumor-bearing mice. Leveraging in vitro, in vivo and in silico data, we have developed a QSP platform that captures the observed preclinical tumor responses and allows for systemic predictions under a variety of conditions. A 5-compartment model was employed to account for the pharmacokinetics, cellular interactions and signaling within the tumor, lymph node, peritoneum, blood and periphery. We model the intratumoral (i.t.) injection of the mRNA mixture and its subsequent uptake, translation and secretion of activated cytokines that induce an immune response. Specifically, when released into the tumor, these cytokines promote tumor killing and trigger the activation and proliferation of CD4+/CD8+ T lymphocytes and NK cells. The model’s simulation results are well aligned with our preclinical data; indicating increased tumor regression with escalating doses of the mRNA monotherapy. The wealth of data and the intertwined information derived from the interaction of receptors and ligands defining the T cell phenotype necessitate a systems approach in order to identify suitable targets and mechanisms of drug action. Our murine immuno-oncology QSP model could be translated across species and be used as part of a computational platform to test various assets with similar MoA.

Citation Format: Kamau Pierre, Lin Lin, Lore Gruenbaum, Carissa Young, Joshua Apgar, Christian Hotz, Timothy Wagenaar, Spyros K. Stamatelos. Development of a multiscale QSP model to characterize the tumor suppressive effects of a cytokine mRNA immunotherapy in a preclinical melanoma mouse model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 685.
Abstract 686: Quantitative analysis of the role of homologous recombination in response to radiotherapy for prostate cancer
Authors: Qian Mengdi , Almasan Alexandru , Gürkan-Çavusoglu Evren
Published: August 2019

The purpose of this study is to computationally analyze how the interaction between androgen receptor (AR) and homologous recombination (HR) affects the treatment outcome for ionizing radiation (IR) combined with androgen deprivation therapy (ADT) for prostate cancer (PCa). Combination treatment with radiation and ADT is currently a standard treatment for PCa. The effectiveness of radiation treatment alone depends on the cells’ capacity to repair the damage that is mostly in the form of double-strand breaks (DSBs). Two major pathways that repair DSBs are non-homologous end joining (NHEJ) and HR. The experimental data in the literature show that AR promotes both NHEJ and HR following IR, and inhibition of AR by ADT impairs both of these pathways in PCa cells leading to either increased radiosensitivity or sensitization to PARP inhibitors. In our previous work, we developed mathematical models of the NHEJ pathway and in this current work we have developed such models for HR to comprehensively analyze the response of PCa cells to IR combined with ADT. We have modeled HR using a series of ordinary differential equations. The parameters that needed to be estimated are the kinetic rate constants, and we have used least square estimation to obtain these model parameters. The data sets used in the parameter estimation were obtained from the literature and they were from both in vitro experiments as well as clinical data from PCa patients. The experimental data show that AR influences the DNA end resection that is required for proficient HR and we have computationally included this effect in the kinetics of the models. We have developed models for IR treatment alone or in combination with ADT. We have carried out sensitivity analysis and identifiability tests on all the parameters from both models in order to determine the parameters that are reliably estimated. The outputs from both NHEJ and HR models show that the suppression of AR activity through ADT has the potential to enhance the IR treatment outcomes for PCa patients. The impairment of HR by ADT also opens up an avenue for achieving synthetic lethality using PARP inhibitors as shown in the literature; in the future we are planning to extend our modeling efforts to include the effect of PARP inhibitors on the treatment outcome.

Citation Format: Mengdi Qian, Alexandru Almasan, Evren Gürkan-Çavusoglu. Quantitative analysis of the role of homologous recombination in response to radiotherapy for prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 686.
Abstract 702: Kinetic analysis identifies determinants of sensitivity to MEK inhibitor-induced cell death
Authors: Inde Zintis , Han Kyuho , Bassik Michael C. , Dixon Scott J.
Published: August 2019

Successful identification of the genetic determinants of drug sensitivity has been a long-standing goal of cancer research and, more recently, of precision medicine. In cancer cells, drug treatment can induce both growth arrest and death. The distinction between these outcomes is important but can be overlooked in large-scale analyses that rely on traditional metabolism-based methods for quantifying cell viability. We recently demonstrated that Scalable Time-Lapse Analysis of Cell Death Kinetics (STACK) effectively quantifies cell death in response to diverse lethal stimuli. We investigated cases in which this approach captured drug-induced lethality more effectively than traditional assays. We found that inhibitors of mitogen activated protein kinase 1 and 2 (MEK1/2) arrested proliferation in diverse cancer cell lines, but induced cell death in only a subset of these lines. We sought to identify the factors that determine whether a cancer cell will undergo growth arrest or death in response to MEK inhibition. MAP kinase pathway activation has previously been reported as a determinant of MEK inhibitor sensitivity; we determined that the dynamics of Bcl-2 family proteins in response to MEK inhibitor treatment correlate with death sensitivity independent of pathway activation. In a genome-wide CRISPR screen, we identified a lipid metabolic enzyme that is a novel modulator of MEKi sensitivity. Our results suggest new approaches for predicting and enhancing sensitivity to cancer therapeutics in tumors and demonstrate that direct measurement of cell death provides clear advantages over proliferation-based metrics.

Citation Format: Zintis Inde, Kyuho Han, Michael C. Bassik, Scott J. Dixon. Kinetic analysis identifies determinants of sensitivity to MEK inhibitor-induced cell death [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 702.