bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 1513: PI3Kγ inhibition activates T cell memory and relieves T cell exhaustion through the reprogramming of tumor-associated macrophages
Authors: Takahashi Hideyuki , Pathria Paulina , Shih Ann , Shepard Ryan M. , Paradise Marc A. , Varner Judith A.
Published: August 2019

We previously reported that macrophage PI3-kinase γ (PI3Kγ) controls a critical switch between immune stimulation and suppression during inflammation and cancer. PI3Kγ inhibition repolarizes tumor-associated macrophages, leading to downregulation of immune suppressive factors such as Arginase and IL10 and upregulation of IL12 and other pro-inflammatory cytokines. This results in recruitment and activation of intratumoral CD8+ T cells, as well as induction of immunological memory (Kaneda et al 2016). In the present study, we investigated the effect of PI3Kγ inhibition on T cell immune responses, including T cell memory induction and T cell exhaustion, in mouse models of head and neck squamous cell carcinomas (HNSCC). We found that Pik3cg−/− mice cleared implanted HPV+ HNSCC tumors; when re-challenged with tumor cells, these mice rapidly cleared secondary tumors and remained cancer-free. The proportion of T cells, especially CD8+ T cells, significantly increased in primary tumors from Pik3cg−/− mice. These CD8+ T cells expressed significantly more granzyme B and interferon and less T cell exhaustion markers than T cells from WT animals, indicating that PI3Kγ inhibition in macrophages results in T cell activation. We found that anti-tumor activity was transferable, as adoptive transfer of splenic T cells from Pik3cg−/− mice to naive WT mice suppressed tumor growth. Accordingly, Pik3cg−/− mice with primary or secondary tumors exhibited more splenic CD62L-CD44+ CD8+ effector memory T cells than WT mice. In summary, Pik3cg−/− mice exhibit a more activated T cell immune response and T cell memory than WT mice, resulting significant suppression of tumor growth. These results suggest that PI3Kγ-targeted therapy may activate durable T cell immune responses in patients with HNSCC.

Citation Format: Hideyuki Takahashi, Paulina Pathria, Ann Shih, Ryan M. Shepard, Marc A. Paradise, Judith A. Varner. PI3Kγ inhibition activates T cell memory and relieves T cell exhaustion through the reprogramming of tumor-associated macrophages [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 1513.
Abstract 1515: Removal of innate suppressors facilitates tumor-immune surveillance
Authors: Zhang Yao , Lee Christina , Diao Na , Li Liwu
Published: August 2019

Although tumor immune environment is increasingly recognized to be highly important during the modulation of tumorigenesis and tumor regression, the role and regulation of innate leukocytes such as neutrophils during the modulation of tumor immune environment remain controversial and less defined. In this study, we tested the hypothesis that removal of innate signaling suppressors may boost the anti-tumor immune function of innate neutrophils in vitro and in vivo. To this regard, we examined two key innate signaling suppressors Tollip and IRAK-M and their roles in modulating neutrophil anti-tumor immune functions. We observed that selective deletion of Tollip enhanced tumor immune surveillance in the AOM-DSS chemically induced colon cancer model. Tollip deficiency released the neutrophil suppression on T cell proliferation and activation. The adoptive transfer of Tollip deficient neutrophils were sufficient to transfer enhanced tumor immune surveillance and reduce tumor burden. Likewise, the study of another innate suppressor IRAK-M revealed that IRAK-M expression was up-regulated in the human patients with colorectal cancer. We also demonstrated that IRAK-M deficient mice exhibited reduced tumor burden following AOM-DSS challenge. Together, our data reveal a novel anti-tumor immune-enhancement strategy through utilizing reprogrammed neutrophils with targeted removal of innate signaling suppressors.

Citation Format: Yao Zhang, Christina Lee, Na Diao, Liwu Li. Removal of innate suppressors facilitates tumor-immune surveillance [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 1515.
Abstract 1519: The impact of ICOS+ Tregs on prognosis of gastric cancer patients
Authors: Urakawa Shinya , Wada Hisashi , Mori Masaki , Doki Yuichiro
Published: August 2019

Background and Aim: Foxp3+ CD4+ regulatory T cells (Tregs) have a suppressive role in antitumor immunity. Among Foxp3+ CD4+ population, effector Tregs (eTregs) with highly suppressive functions are located in a subpopulation of Tregs. We have reported that ICOS has the potential as a novel marker for eTregs in gastric cancer (GC) and ICOS+ Tregs were abundant in H. pylori (HP) Ab-positive GC patients. In the present study, we investigate whether HP induce ICOS+ Tregs in GC.

Materials and Methods: Tumor-infiltrating lymphocytes (TILs), normal mucosa-infiltrating lymphocytes (NILs) and peripheral blood mononuclear cells (PBMCs) were obtained from 117 gastric cancer patients. Tregs, ICOS+ Tregs, linage- CD11c- CD123+ HLA-DR+ plasmacytoid dendritic cells (pDCs), TLR9+pDCs, ICOS-L+ pDCs were analyzed by flow cytometry and multicolor immunohistochemistry. HP Ab was analyzed by ELISA. For induction assay of ICOS+ Tregs, naïve CD4 T cells were cultured with pDCs under stimulation with TGF-β, CD3/CD28 mAbs and frozen-and-thawed HP (NCTC11637).

Results: In GC tissues, %ICOS-L in pDCs was positively correlated with %ICOS in Tregs (r2=0.52, p<0.001). %TLR9 in pDCs and %ICOS-L in pDCs were significantly higher in HP Ab-positive patients than others (p=0.001 and p=0.042, respectively). %ICOS+ in Tregs was significantly higher in HP-Ab positive patients than others (p=0.020). By multicolor immunohistochemistry, a large number of ICOS/Foxp3 double positive cells were observed. In induction assay, addition of HP (NCTC11637) increased the expression of ICOS-L in pDC and induction of ICOS+ Tregs, which were suppressed by TLR9 antagonist. %ICOS+ in Tregs were significantly lower in HP-eradicated patients than others (p<0.001). Interestingly, %ICOS+ in Tregs were also significantly lower in patients eradicated within four weeks before their surgical treatments (p<0.001).

Conclusion: Our results indicate the induction pathway from HP to ICOS+ Tregs mediated by TLR9 and ICOS-L in pDCs. Preoperative eradication for HP may have a potential as an indirect immune therapy for gastric cancer patients.

Citation Format: Shinya Urakawa, Hisashi Wada, Masaki Mori, Yuichiro Doki. The impact of ICOS+ Tregs on prognosis of gastric cancer patients [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 1519.
Abstract 1521: Tumor-produced hyaluronan contributes to the formation tolerogenic immunosuppressive microenvironment
Authors: Dominguez-Gutierrez Paul R. , Crispen Paul , Kusmartsev Sergei A.
Published: August 2019

Immunosuppressive ligand PD-L1 considered as a major player in mechanism of negative regulation of anti-tumor immune response and its expression is highly up-regulated in human and experimental tumors, including bladder cancer. Bladder cancer is characterized by aberrant hyaluronan metabolism resulting in increased HA production in tumor tissue. Hyaluronan or hyaluronic acid (HA) is a prominent component of tumor stroma/microenvironment. Membrane-bound or free extracellular HA favors tumor progression by inducing tumor cell motility, invasive properties, proliferation, production of growth factors and epithelial-mesenchymal transition. Here, we provide evidence that tumor-produced hyaluronan, one of the key tumor stroma components, contributes to the formation of tolerogenic/immunosuppressive tumor microenvironment and stimulated PD-L1 expression. We found that tumor-derived HA specifically binds to CD44 receptor expressed by myeloid precursors, such as myeloid-derived suppressor cells (MDSCs) and promotes its expansion with differentiation toward PD-L1-expressing F4/80+ macrophages. Inhibition of HA synthesis in tumor cells with pharmacologic inhibitor 4-MU, or blockade of CD44 signaling in myeloid cells with antagonistic anti-CD44 antibody, prevented the macrophage differentiation and tumor-induced up-regulation of PD-L1 expression. We also found that tumor-derived HA stimulated production of immunosuppressive and inflammatory factors IL-6, IL-10, TNF-alpha, IL-1beta and PGE2 by myeloid cells in CD44-dependent manner. Moreover, tumor-produced HA stimulated development of PD-L1-expressing macrophages in both murine and human myeloid cells. Our study reveals that tumors may evade the immune system by creating a protective tolerogenic “shield” in the form of tumor-produced HA, which binds to the CD44-expressing tumor-recruited MDSCs, stimulating production of immunosuppressive factors and promoting development of the PD-L1+ macrophages. Inhibiting of hyaluronan synthesis by tumors or targeting HA-CD44 signaling could provide an attractive approach to break tumor-induced immune tolerance and unleash the anti-tumor immune response.

Citation Format: Paul R. Dominguez-Gutierrez, Paul Crispen, Sergei A. Kusmartsev. Tumor-produced hyaluronan contributes to the formation tolerogenic immunosuppressive microenvironment [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 1521.
Abstract 1523: Inhibition of SUMOylation by TAK-981 induces antitumor innate immune responses by modulating macrophage and NK cell function through Type I IFN pathway activation
Authors: Nakamura Akito , Grossman Stephen , Song Keli , Idamakanti Neeraja , Shapiro Gary , Huszar Dennis
Published: August 2019

TAK-981 is a novel and selective small molecule inhibitor of the small ubiquitin-like modifier (SUMO) ylation enzymatic cascade in Phase 1 clinical trials. SUMOylation is a reversible post-translational modification that regulates protein function by covalent attachment of a SUMO protein to protein substrates. We have found that in vivo inhibition with TAK-981 promotes an antitumor immune response characterized by induction of a Type I interferon (IFN) response in immune cells. Interestingly, others have also reported a role for SUMOylation in restraining Type I IFN responses, upon exposure to pathogenic stimuli, using genetic approaches to inhibit SUMOylation. In this study, we demonstrate that inhibition of SUMOylation with TAK-981 enhances antitumor innate immunity by modulating macrophage and NK cell function. In vitro studies revealed that TAK-981 treatment increased expression of pro-inflammatory markers and prevented expression of anti-inflammatory markers on macrophages. TAK-981 treatment of macrophages further resulted in potent phagocytic activity against cancer cells. TAK-981 also induced expression of activation markers on NK cells and enhanced cell killing activity against cancer cells. Enhancement of macrophage phagocytosis and NK cell cytotoxicity by TAK-981 were shown to be dependent on Type I IFN receptor signaling, and both activities against CD20-positive cancer cells were further enhanced in the presence of the anti-CD20 therapeutic monoclonal antibody rituximab. Evaluation of combination activity in vivo in CD20-positive lymphoma xenograft models demonstrated synergistic antitumor activity in multiple models when TAK-981 was combined with rituximab. Inhibiting SUMOylation with TAK-981 appears to represent a novel and mechanistically unique means to the end of leveraging the potential of Type I IFNs to promote antitumor immune responses.

Citation Format: Akito Nakamura, Stephen Grossman, Keli Song, Neeraja Idamakanti, Gary Shapiro, Dennis Huszar. Inhibition of SUMOylation by TAK-981 induces antitumor innate immune responses by modulating macrophage and NK cell function through Type I IFN pathway activation [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 1523.
Abstract 1531: The Polycomb repressor complex 1 promotes recruitment of myeloid-derived suppressor cells and immune evasion during bone colonization in castration-resistant prostate cancer
Authors: Su Wenjing , Zhang Boyu , Han Hyunho , Chakraborty Goutam , Zhou Bing , Su Jie , Yang Guangli , Ouerfelli Ouathek , Rosen Neal , Scher Howard I. , Giancotti Filippo G.
Published: August 2019

The mechanisms that enable immune evasion at metastatic sites are poorly understood. We show that the Polycomb Repressor Complex-1 (PRC1) drives colonization of the bones and visceral organs in Double Negative (AR- NE-) Prostate Cancer (DNPC). In vivo genetic screening identifies the cytokine CCL2 as the top pro-metastatic gene induced by PRC1. Mechanistic studies show that CCL2 not only controls self-renewal and metastatic initiation but also governs the recruitment of M2-like TAMs and Tregs, thus creating a profoundly immune suppressive and proangiogenic microenvironment. Inhibition of PRC1 reverses these processes and cooperates with checkpoint immunotherapy to suppress multi-organ site metastasis. These results reveal a link between epigenetic regulation of cancer stem cells and molding of the tumor microenvironment and identify PRC1 as a potential therapeutic target in M-CRPC.

Citation Format: Wenjing Su, Boyu Zhang, Hyunho Han, Goutam Chakraborty, Bing Zhou, Jie Su, Guangli Yang, Ouathek Ouerfelli, Neal Rosen, Howard I. Scher, Filippo G. Giancotti. The Polycomb repressor complex 1 promotes recruitment of myeloid-derived suppressor cells and immune evasion during bone colonization in castration-resistant 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 1531.
Abstract 1539: Mechanisms of action of bispecific T cell engager-mediated immune response in a lymphoma tumor model
Authors: Coupet Tiffany A. , Godbersen-Palmer Claire , Sentman Charles L.
Published: August 2019

Bispecific T cell Engagers are molecules composed of two single chain variable fragments where one arm binds CD3 on T cells and redirects them to a tumor antigen with the other arm. This causes immune synapse formation between the T cell and tumor cell resulting in T cell activation and destruction of tumor cells. Bispecific T cell engagers have been used successfully in the clinic, however, it is unclear which activities of the host immune system are required for efficacy. This study investigates the mechanisms of action of a Bispecific protein specific for the B7H6 tumor antigen in an immune intact tumor model of lymphoma. In this lymphoma model the median survival for the B7H6xCD3 bispecific treated group was greater than 80 days while the median survival of the control bispecific treated group was 20 days. Monitoring of cellular changes in the bone marrow, blood, spleen and lymph nodes by flow cytometry 24h after bispecific protein treatment revealed that most cellular changes occurred in the inguinal lymph nodes were increases in CD8+ T cell and NK cells while CD4+ T cells decreased. Additionally, intracellular staining of cytokines IFNγ, Mip1α and TNFα in mouse T cells cultured in vitro with target tumor cells and bispecific protein showed that CD8+ T cells had greater polyfunctionality than CD4+ T cells. We have shown that IFNγ is essential for efficacy against lymphoma in vivo. To study the relative contribution of CD4 and CD8 T cells in vivo, lymphoma bearing mice that were depleted of CD4+ T cells or were deficient in CD8+ T cells were monitored for survival after bispecific protein treatment. While both CD4 or CD8 deficient mice had a greater survival when treated with B7H6xCD3 bispecific compared to control bispecific protein, the loss of either cell type resulted in much lower survival compared to WT mice treated with B7H6xCD3. All WT mice receiving B7H6xCD3 bispecific protein survived at least 65 days compared to CD4-depleted mice (median survival 20 days) and CD8-deficient mice (median survival 30 days) receiving the same treatment. In conclusion, both CD4+ and CD8+ T cells play a critical role in bispecific therapy. Understanding the mechanisms of action of bispecific proteins in vivo will help to develop more effective ways to use these powerful immune activating proteins to treat cancer.

Citation Format: Tiffany A. Coupet, Claire Godbersen-Palmer, Charles L. Sentman. Mechanisms of action of bispecific T cell engager-mediated immune response in a lymphoma tumor 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 1539.
Abstract 1544: Cell penetrating single domain antibody (sdAb) SBT-100 binds KRAS and inhibits growth of human cancers with KRAS activating mutations
Authors: Singh Sunanda , Murillo Genoveva , Singh Avani , Singh Samara , Parihar Meenakshi , Singh Anjali , Mehta Rajendra , Parihar Ashutosh
Published: August 2019

Background: Despite nearly fourth years of research, scientists have failed to develop a clinically viable therapy against KRAS, one of the deadliest families of cancer-causing proteins. Mutations in KRAS are prevalent amongst the top three most deadly cancer types in the United States: pancreatic (95%), colorectal (45%), and lung (35%). KRAS has been thought to be undruggable due to: 1) its intracellular location and lack of binding pockets for small molecules; 2) the high (pM) affinity of RAS for GTP precludes direct targeting of the nucleotide binding pocket; 3) high intracellular concentrations of GTP (uM) inhibits competition for the nucleotide-binding pocket by small molecules; and 4) possible toxicity. Mutations of KRAS result in it being perpetually turned on to propagate signal down the MAPK pathway. This results in constant production of P-ERK and plays an important role in malignant development. To overcome these challenges, Singh Biotechnology has developed SBT-100 a first in class & best in class novel sdAb that penetrates the cell membrane to bind KRAS to inhibit its GTPase activity.

Methods: Human cancer cell lines were purchased from ATCC. BIAcore affinity studies were conducted by Precision Antibody. KRAS GTPase assay was purchased from Promega. Levels of P-ERK were determined using western blots. In vitro cell growth suppression was tested with MTT assay. Athymic nude mice for xenograft studies were purchased from Envigo.

Results: SBT-100 binds KRAS with KD=10-9 and KRAS(G12D) with KD=10-7 as demonstrated by BIAcore affinity assay. Both SBT-100 and SBT-102 significantly inhibit KRAS GTPase activity in vitro and inhibition is comparable to polyclonal antibody to KRAS. Growth of MDA-MB-231 cells with KRAS(G13D) mutation and PANC-1 cells with KRAS(G12D) mutation are significantly decreased in the MTT assay when incubated with SBT-100. Additionally, same cell lines have significantly decreased P-ERK expression when cultured with SBT-100. Xenograft studies demonstrate significant growth suppression of MDA-MB-231 and PANC-1 when treated with SBT-100 in vivo.

Conclusion: SBT-100, crosses the cell membrane, binds to KRAS intracellularly and its most common mutant with nanomolar affinity, inhibits KRAS GTPase activity, downregulates P-ERK signaling, and suppresses the growth of cancers cells in vitro and in vivo without showing any toxic effects.

Citation Format: Sunanda Singh, Genoveva Murillo, Avani Singh, Samara Singh, Meenakshi Parihar, Anjali Singh, Rajendra Mehta, Ashutosh Parihar. Cell penetrating single domain antibody (sdAb) SBT-100 binds KRAS and inhibits growth of human cancers with KRAS activating mutations [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 1544.
Abstract 1550: Bruteforcing immune oncology discovery with computational immuno-engineering
Authors: Ives Sarah , Maurer David , Pettus Christina , Newland Raymond , Chiou Valerie , Daraeikia Shahrad , Jones Chelsea , Hervold Kieran , Day Giles , Smith Chris , Waddell Ian D. , Youssef Sawsan , Glanville Jacob
Published: August 2019

Recent Nobel awards in immune checkpoint inhibitor biology, phage display discovery and protein evolution highlight our current golden age of immune oncology research. While it took 15 years to bring anti-CTLA4 and anti-PD1 therapeutics from conception to global patient populations, new advances in synthetic and data driven immune engineering are enabling new therapeutics to be discovered and engineered in weeks rather than years. Here we review ten years of progress in computational optimization of antibody discovery libraries through the lens of high-throughput data collection technologies, with specific case studies of modern repertoire design principles applied to a panel of immune checkpoint targets. We emphasize the case study of PD1, where a computationally optimized library generated over 6500 unique anti-PD1 antibodies in two weeks, including picomolar binders, mouse/cyno/human triple cross-reactive epitopes, antagonists, agonists, and saturated epitope coverage of the target.

Citation Format: Sarah Ives, David Maurer, Christina Pettus, Raymond Newland, Valerie Chiou, Shahrad Daraeikia, Chelsea Jones, Kieran Hervold, Giles Day, Chris Smith, Ian D. Waddell, Sawsan Youssef, Jacob Glanville. Bruteforcing immune oncology discovery with computational immuno-engineering [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 1550.
Abstract 1556: Preclinical development of antibody drug conjugates targetting EGFRvIII
Authors: Jaramillo Maria Luz , Marcil Anne , Robert Alma , Jolicoeur Normand , Wu Cunle , Fortin Yves , Donates Yuneivy Cepero , Acchione Mauro , Slinn Jacqueline , Ling Binbing , Moreno Maria
Published: August 2019

EGFRvIII is a naturally occurring variant of epidermal growth factor receptor (EGFR) that results from an in-frame deletion that removes 267 amino acids from the extracellular domain. EGFRvIII is a tumor-specific receptor that is amplified and present in 25-64% of glioblastoma multiforme and in 20-36% of breast cancers. Numerous studies show that normal tissues are devoid of EGFRvIII, thus making this target ideal for development as an antibody drug conjugate (ADC) for the treatment of cancer,including glioblastoma.

At the National Research Council (NRC) of Canada, we have selected mouse monoclonal mAbs that are selective for the extracellular domain of EGFRvIII and which have been shown to be internalized into EGFRvIII expressing cells for ADC development . A panel of EGFRvIII internalizing antibodies was directly conjugated to maytansine, the microtubule disrupting agent through a noncleavable linker. EGFRvIII -DM1 ADCs were shown to efficiently induce growth inhibition in vitro, in EGFRvIII expressing U87MG and DKMG glioblastoma cells. When tested in vivo, EGFRvIII -DM1 ADCs were shown to have potent anti-tumor activity in the U87MG-EGFRIII expressing tumor xenograft model.

Citation Format: Maria Luz Jaramillo, Anne Marcil, Alma Robert, Normand Jolicoeur, Cunle Wu, Yves Fortin, Yuneivy Cepero Donates, Mauro Acchione, Jacqueline Slinn, Binbing Ling, Maria Moreno. Preclinical development of antibody drug conjugates targetting EGFRvIII [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 1556.
Abstract 157: APE1 upregulates MMP-14 to promote invasion of esophageal adenocarcinoma via redox-sensitive ARF6-mediated recycling
Authors: Lu Heng , Bhat Ajaz A. , Peng Dunfa , Chen Zheng , Zhu Shoumin , Hong Jun , Maacha Selma , Robbins David , Belkhiri Abbes , El-Rifai Wael
Published: August 2019

The incidence of Barrett's esophagus (BE) and esophageal adenocarcinoma (EAC) has increased dramatically in the past three decades. The development of BE and its progression to EAC is highly correlated with exposure to acidic bile salts due to chronic gastroesophageal reflux disease (GERD). A stimulated overexpression of APE1 has been identified in response to bile acids for oxidative DNA repair and oncogenic signal transduction in BE and EAC, but function and mechanism of APE1 in BE and EAC development remains largely unknown. Here, we demonstrate a new function of APE1 in promoting invasion of dysplastic BE and EAC cells that is dependent on its redox function. We observed aberrant overexpression of APE1 in the cell lines and patients’ samples of dysplastic BE and EAC. In contrast to wild-type APE1, overexpression of redox-defective mutant, C65A, or treatment with APE1-redox-specific inhibitor, E3330, abrogated the pro-invasive phenotype of APE1. Mechanistically, we found that APE1 upregulated protein levels of the key matrix metalloproteinase MMP-14. Knockdown of APE1 decreased MMP-14 protein levels in dysplastic BE and EAC cells. Zymography assays indicated APE1 silencing reduced MMP-14 activity, subsequently impaired MMP-2 activation, and repressed extracellular matrix (ECM) degradation. Further, endocytosis and recycling assays revealed decreased endocytosis/recycling of MMP-14 protein in APE1-knockdown cells. Interestingly, our immunoprecipitation and proximity ligation assay (PLA) revealed a novel interaction between APE1 and ARF6, a key regulator of MMP-14 recycling. This interaction between APE1 and ARF6 activates ARF6 to regulate MMP-14 recycling through APE1-dependent redox function.

Conclusion: Our findings demonstrate, for the first time, the role of APE1 redox function in upregulating MMP-14 protein levels through activation of ARF6-mediated MMP-14 recycling. We propose APE1/ARF6/MMP-14 as a novel signaling axis in the invasion and progression of dysplastic BE and EAC.

Citation Format: Heng Lu, Ajaz A. Bhat, Dunfa Peng, Zheng Chen, Shoumin Zhu, Jun Hong, Selma Maacha, David Robbins, Abbes Belkhiri, Wael El-Rifai. APE1 upregulates MMP-14 to promote invasion of esophageal adenocarcinoma via redox-sensitive ARF6-mediated recycling [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 157.
Abstract 1578: Cohesin complex-related genes in colorectal cancer
Authors: Sasaki Masaru , Miyoshi Norikatsu , Saso Kazuhiro , Fujino Shiki , Takahashi Hidekazu , Haraguchi Naotsugu , Matsuda Chu , Hata Taishi , Yamamoto Hirofumi , Mizushima Tsunekazu , Mori Masaki , Doki Yuichiro
Published: August 2019

Backgrounds: One of the hallmarks of cancer is chromosomal instability and it leads to aneuploidy. Defective sister chromatid cohesion represents a major cause of chromosome instability in human cancers. Stromal antigen (STAG) encodes a subunit of the cohesin complex, which regulates cohesion and segregation of sister chromatids. STAG contains STAG1, STAG2 related to somatic division and STAG3 related to meiosis. We evaluated the relationship between STAG and colorectal cancer.

Materials and methods: We examined STAG mRNA expression in tumor tissues by real-time qPCR. The samples were obtained from 172 colorectal cancer patients who underwent curative resection from November 2009 to December 2013 at the Osaka International Cancer Institute, Japan. STAG mRNA expression was evaluated by comparing with clinicopathological features and patients’ survival. Patients were classified into a high STAG expression and low STAG expression groups. Kaplan-Meier survival curves were evaluated using the log-rank test. The association with STAG expression and prognosis was analyzed by the Cox proportional regression model. Then, we utilized siRNA to knock down the expression of STAG3 and examined whether this altered proliferation in colorectal cancer cell lines (HCT116, RKO, HT29 and SW480).

Results: STAG1 and STAG2 did not show no statistically significant differences in disease-free survival (DFS) and overall survival (OS). In contrast, DFS rate was significantly lower in the high STAG3 expression group than the low STAG3 expression group (P = 0.032). A multivariate analysis showed that the high STAG3 mRNA expression was a significant independent risk factor for the recurrence (P = 0.006). In patients with adjuvant chemotherapy, the high STAG3 expression group was significantly worse for DFS (P = 0.043) and OS (P = 0.020), compared to the low STAG3 expression group. However, the proliferation assays evaluating the knockdown of STAG3 did not show any significant differences.

Conclusions: Our study showed that STAG3 can be a novel prognostic biomarker and the high STAG3 mRNA expression was an independent risk factor for the recurrence, suggesting that it relates to the chemotherapy resistance in colorectal cancer. We perform some other assays to evaluate the biology (focusing on the cancer invasiveness, the drug sensitivity, etc.) which reveal the mechanism of STAG3 in colorectal cancer.

Citation Format: Masaru Sasaki, Norikatsu Miyoshi, Kazuhiro Saso, Shiki Fujino, Hidekazu Takahashi, Naotsugu Haraguchi, Chu Matsuda, Taishi Hata, Hirofumi Yamamoto, Tsunekazu Mizushima, Masaki Mori, Yuichiro Doki. Cohesin complex-related genes in colorectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1578.
Abstract 1580: Genetic variability of H3K27me modifier genesEZH2,KDM6AandKDM6Bin association with pancreatic cancer risk
Authors: Lu Ye , Obazee Ofure , Canzian Federico
Published: August 2019

Background:

Several literature reports explain the critical role of epigenetic regulation in relation to different types of cancers, however this is still an emerging research area in pancreatic cancer. Methylation of lysine 27 on histone H3 (H3K27me) plays a critical role in regulating gene expression and this modification has been reported to have oncogenic effects. Specifically, in pancreatic cancer this mechanism has only been demonstrated in relation to patient outcome.

The demethylase KDM6A (UTX) or KDM6B (JMJD3, a paralog of KDM6A on a different chromosome), and methyltransferase EZH2 (KMT6A) specifically regulate the alteration level of H3K27me. Based on the hypothesis that genetic variants may influence overall gene function, it is plausible that single nucleotide polymorphisms (SNPs) in these genes may similarly affect the roles of these genes in H3K27me deregulation.

Materials and methods:

Using the SNPinfo tool, a total of 21 tag SNPs in EZH2, KDM6A and KDM6B were selected from European populations based on 1000 Genome project. SNPs below 80% linkage disequilibrium threshold or less than 5% frequency among Europeans were excluded.

These SNPs were analysed in relation to pancreatic cancer susceptibility using logistic regression among up to 8,741 pancreatic cancer cases and 6,957 controls from publically-available GWAS data (Pancreatic Cancer Cohort Consortium (PanScan) and Pancreatic Cancer Case-Control Consortium (PanC4)). Imputation of these data sets were performed according to standard protocol and used for subsequent analyses.

Results:

Following adjustment for age and gender, we observed promising associations between KDM6B rs12453250 C>A and EZH2 rs2888566 T>C ((OR=0.92 95% CI (0.85-0.99), P=0.018) and (OR=1.09 95% CI (1.03-1.17), P=0.007) respectively) and pancreatic cancer risk. Interestingly, rs12453250 results in an amino acid change from Phenylalanine (F) to Leucine (L) which is predicted to have a probably-damaging effect on the KDM6B protein.

Conclusions:

The extent to which epigenetic markers can be incorporated into pancreatic cancer risk prediction along with genetic information is unknown. Our novel findings suggest a plausible role of EZH2 and KDM6A SNPs in relation to pancreatic cancer risk among carriers of their minor alleles. These results warrant further validation in independent studies and may enhance systematic risk assessment among Europeans.

Citation Format: Ye Lu, Ofure Obazee, Federico Canzian. Genetic variability of H3K27me modifier genesEZH2,KDM6AandKDM6Bin association with pancreatic cancer risk [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 1580.
Abstract 1582: Catechol-O-methyltransferase (COMT) genotypes modify the effects of beta-carotene supplementation on cancer incidence in a controlled trial: findings from the ATBC Study
Authors: Weinstein Stephanie J. , Huang Jiaqi , Hall Kathryn Tayo , Sesso Howard D. , Albanes Demetrius
Published: August 2019

Large cancer prevention trials of vitamin supplementation have yielded mixed results over the past three decades. Whether and how genetic variation that influences oxidative stress or vitamin absorption, transport, and metabolism can modify responses to supplementation remains to be elucidated. Catechol-O-methyltransferase (COMT) genotypes have been shown to impact the effects of vitamin E (i.e., alpha-tocopherol) supplementation on cancer, and the present pharmacogenetic analysis examines interactions among COMT, beta-carotene supplements, and risk of cancer. In a case-control study nested within the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study of 29,133 Finnish men, we examined overall cancer risk based on the randomized assignment to beta-carotene supplementation (BC; 20 mg daily for 5-8 years) and two common genetic variants in COMT, rs4680 and rs4818 (genotyped by Illumina scans). Based on 2396 cases and 2235 non-cases, Cox proportional hazards models that adjusted for age, smoking intensity and duration, and randomized assignment to the trial vitamin E supplement were conducted to estimate overall cancer risk for the trial and 10-year post-trial periods combined. For rs4680, BC supplementation (versus no BC) was associated with higher cancer risk only in men with the AA (met/met) genotype (HR 1.29, 95% CI 1.08-1.53, P=0.004) as compared with the AG (met/val) and GG (val/val) genotypes (respectively, HR 1.04, 95% CI 0.93-1.16, P=0.52; and, HR 0.99, 95% CI 0.86-1.15, P=0.94). We observed a somewhat similar pattern for rs4818, with the BC supplement being associated with higher cancer risk in men with the GG and GC genotypes (respectively, HR 1.21, 95% CI 0.94-1.55, P=0.14; and, HR 1.15, 95% CI 1.01-1.30, P=0.03), but not the CC genotype (HR 0.99, 95% CI 0.88-1.11, P=0.80). Our findings indicate that the AA (met/met) genotype of COMT rs4680 and the G allele of rs4818 potentiate the increased cancer risk resulting from BC supplementation.

Citation Format: Stephanie J. Weinstein, Jiaqi Huang, Kathryn Tayo Hall, Howard D. Sesso, Demetrius Albanes. Catechol-O-methyltransferase (COMT) genotypes modify the effects of beta-carotene supplementation on cancer incidence in a controlled trial: findings from the ATBC Study [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 1582.
Abstract 1599: Determining patient ancestry based on targeted tumor comprehensive genomic profiling
Authors: Newberg Justin , Connelly Caitlin , Frampton Garrett
Published: August 2019

Background. Cancer gene mutations exhibit mutation patterns of prevalence that vary across different ancestry groups. For example, EGFR variants are more frequent in non-small cell lung cancer among people with Asian ancestry, and KRAS variants are observed more frequently in colorectal cancer among patients with African American ancestry. Additionally, many histological subtypes of cancers demonstrate differences in prevalence between people of different ancestry. However, many cancer studies lack the statistical power to identify such nuances. The large cohort of patients who have undergone comprehensive cancer genomic profiling at Foundation Medicine may provide a useful starting point for characterizing these mutation patterns across ancestry groups.

Methods. To establish the ancestry on de-identified samples, we superimposed SNPs targeted by each of our comprehensive genomic profiling tests (FoundationOne, FoundationOne CDx, FoundationOne Heme) with Phase 3 1000 Genomes data. Using an established approach, we projected the SNPs down to the top five principal components and used random forest ensemble learning to train a classifier on each bait set. 10-fold cross-validation indicates this approach performs with 98-99% precision and recall for the different genomic profiling tests.

Results. Ancestry calls were made on over 170,000 de-identified samples consented for research. Initial analyses indicated that classification of American samples was not as robust as other groups. To address this, we trained classifiers on a per-chromosome basis, and re-assigned samples which exhibited less than 80% consensus across chromosomes to an admixture group. Overall prevalence of patient ancestry in the dataset is 75.9% European, 8.3% African, 4.7% East Asian, 0.8% South Asian, and 0.8% American, and 9.5% admixed. From the resulting data, we summarize cancer types that are well-represented across populations, identifying at least 28 tumor types for which we likely have power to identify ancestry-dependent somatic mutations.

Discussion. The dataset described contains a previously unavailable set of cancer types to be mined for ancestry-dependent cancer-driving alterations. Those results will be presented. The ancestry classification approach described in this work can be applied to a range of genomic profiling tests, and refinements on this approach can be integrated into clinical trials and ultimately clinical care to better elucidate varied biologic behavior across advanced cancer.

Citation Format: Justin Newberg, Caitlin Connelly, Garrett Frampton. Determining patient ancestry based on targeted tumor comprehensive genomic profiling [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 1599.
Abstract 1615: Correlation between demographic factors, dietary habits and urinary micronutrient content among minority groups in New York City
Authors: Zambrano Cristina , Beeber Maayan , Panitz April , Wyka Katarzyna , Ibrahim Safa , Tan Yin , Ma Grace , Navder Khursheed , Yeh Ming-Chin , Ogunwobi Olorunseun
Published: August 2019

Cancer is the second leading cause of death in the United States. A diet low in fruits and vegetables increases the risk of certain cancer types. Moreover, socioeconomic factors contribute to limited access to fresh and healthy foods and limited opportunities for safe physical activity, leading to poor physical health. In this multidisciplinary, IRB approved study, we explored relationships between demographic factors, self-reported dietary behaviors and gallic acid, a polyphenolic micronutrient that correlates well with fruit and vegetable intake. We recruited participants at a senior center in East Harlem, New York City, a racially diverse and underserved community. The participants completed a NIH-validated survey through which we assessed their dietary habits and collected standardized demographic data and history of cancer. Urine samples from participants were analyzed for gallic acid. So far, 33 participants completed the survey and 25 of them provided urine samples for gallic acid analysis. We found an association between demographic information (Race/ethnicity and age) and intake of certain foods. Specifically, age was negatively associated with french fries/fried potatoes, cooked dried beans and tomato soup intake (p<0.05) and Black/African American race was associated with increased intake of juice (p<0.05). A positive association between self-reported food intake and gallic acid concentration was only observed with french fries/fried potatoes (R = 0.641, p<0.001). Overall, the results suggest a significant association between dietary habits and demographic factors. Ongoing work include further recruitment of participants, and multivariate analysis of the data. This will be followed by an intervention consisting of active nutritional education, and urinary gallic acid analysis to assess the impact of nutritional education on dietary habits.

Citation Format: Cristina Zambrano, Maayan Beeber, April Panitz, Katarzyna Wyka, Safa Ibrahim, Yin Tan, Grace Ma, Khursheed Navder, Ming-Chin Yeh, Olorunseun Ogunwobi. Correlation between demographic factors, dietary habits and urinary micronutrient content among minority groups in New York City [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 1615.
Abstract 1616: Adjuvant supplementation of docosahexaenoic acid with 2-deoxyglucose, metformin, and aspirin on cellular metabolism in breast, lung, and prostate tumor cells
Authors: Ma Irvin V. , Mouradian Michael , Cooper Andrew R. , Vicente Erika D. , Pardini Ronald S.
Published: August 2019

A standard treatment for cancer often involves the use of adjuvant supplementation with targeted therapy to maximize tumor suppression. Recent studies have shown that docosahexaenoic acid (DHA; C22:6 n-3), a long chain omega-3 polyunsaturated fatty acid, acts on an array of molecular oncogenes that are often targeted by anti-tumorigenic drugs. After a careful review of DHA’s mechanistic properties, 2-deoxyglucose (2DG), metformin, and aspirin were identified as drugs that share similar molecular targets as DHA. 2DG and metformin both target cellular metabolism by inhibiting intracellular ATP, albeit different mechanisms. 2DG inhibits glycolysis, while metformin targets the mitochondria. Aspirin inhibits inflammation via irreversible acetylation of platelet COX. The current study investigates the effects of DHA in combination with each drug on numerous cancer subtypes to determine if concurrent treatments can synergistically inhibit tumor proliferation. In BT-474 human breast ductal carcinoma, MDA-MB-231 human breast adenocarcinoma, and A549 human lung adenocarcinoma, DHA was shown to enhance the tumor-inhibiting effects of 2DG via intracellular ATP reduction. In contrast, DHA showed no effect with metformin on the same tumor cell lines. With limited studies localizing DHA’s metabolic effects, these results suggest that DHA may have potential selectivity for ATP inhibition via glycolysis. In response to DHA + aspirin, the PC-3 prostate adenocarcinoma and MDA-MB-231 displayed synergistic inhibition of cell viability, while LNCaP prostate carcinoma showed an additive effect. With studies showing DHA’s ability to inhibit endothelial COX, further studies will be done to determine whether the synergistic effects of DHA + aspirin expand to COX expression as well. Moreover, downstream targets of 2DG and metformin will be studied to determine the extent of DHA enhancement on oncogenic targets, such as mTOR, 4EB-P1, and GRB10. The results of this study provide preliminary evidence for the efficacy of adjuvant supplementation with DHA in combination with anti-tumorigenic drugs. With ongoing analysis, the potential for adjuvant nutritional supplementation will allow for additional treatment strategies for future patients.

Citation Format: Irvin V. Ma, Michael Mouradian, Andrew R. Cooper, Erika D. Vicente, Ronald S. Pardini. Adjuvant supplementation of docosahexaenoic acid with 2-deoxyglucose, metformin, and aspirin on cellular metabolism in breast, lung, and prostate tumor 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 1616.
Abstract 162: ASB13 inhibits breast cancer progression and metastasis through SNAI2 degradation and transcriptional regulation of YAP
Authors: Fan Huijuan , Wang Xuxiang , Li Wenyang , Shen Minhong , Wei Yong , Zheng Hanqiu , Kang Yibin
Published: August 2019

Metastasis is responsible for the majority of cancer-related deaths. The transcription factor SNAI2 promotes metastasis by facilitating tumor cell invasion and tumor initiating activity. However, its post-translational regulation is less studied. We performed a dual luciferase-based, genome-wide E3 ligase siRNA library screening and identified ASB13 as an E3 ubiquitin ligase that targets SNAI2 for ubiquitination and degradation. ASB13 knockout in breast cancer cells leads to increased cell migration and decreased F-actin polymerization; while overexpression of ASB13 suppresses lung metastasis formed by LM2 cells. Furthermore, we discovered that ASB13 knockout decreases YAP expression, which is dependent on increased SNAI2 protein level. YAP functions as a tumor suppressor gene in breast cancer, as YAP knockout increases tumorsphere formation, anchorage-independent colony formation, and cell migration. Clinical data analysis reveals that ASB13 expression is positively correlated with overall survival in breast cancer patients. These findings establish the ASB13-SNAI2-YAP axis as a regulatory mechanism for breast cancer migration and metastasis.

Citation Format: Huijuan Fan, Xuxiang Wang, Wenyang Li, Minhong Shen, Yong Wei, Hanqiu Zheng, Yibin Kang. ASB13 inhibits breast cancer progression and metastasis through SNAI2 degradation and transcriptional regulation of YAP [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 162.