bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 1218: EMP2 serves as a novel target for immunotoxin mediated ovarian cancer therapy
Authors: Mohamedali Khalid , Kok Su-Yin , Cheung Lawrence H. , Rosenblum Michael G. , Wadehra Madhuri 
Published: August 2019

Abstract
Ovarian cancer (OC) currently accounts for only ~2% of all new cancer cases per year, but once diagnosed, patients only show a 5 year survival of 30%. Subdivided into four subtypes: serous, endometrioid, clear cell, and mucinous carcinoma, high-grade serous ovarian cancer (HGSOC) accounts for 70-80% of the ovarian cancer deaths. Immunoconjugates represent an innovative therapeutic approach to deliver a deadly payload to a tumor cell with more specificity and potentially less avenues for resistance than either can exert individually. However, it has been a challenge to find candidates as well as implement conjugation strategies to achieve these goals for a number of cancers. Epithelial membrane protein-2 (EMP2) is over-expressed in a number of cancers in women including 70% of ovarian tumors, with up to 88% of advanced serous carcinomas showing high expression of the antigen. With an eye towards therapy, we have recently developed an IgG1 targeting the extracellular domain of EMP2 with single digit nM affinity. As the antibody-antigen complex rapidly internalizes, we sought to improve on the efficacy of the naked antibody. Granzyme B (GrB) is a serine protease that plays a critical role in the body’s defense against viral infection and tumor development by initiating the apoptotic cascade via both caspase-dependent and -independent mechanisms. Accordingly, we developed novel fusion proteins composed of the anti-EMP2 backbone as the targeting moiety and granzyme B as the cytotoxic payload. The designs comprised (a) the anti-EMP2 IgG1 with GrB fused to the Fc domain through a cleavable linker, and (b) active GrB fused to the IgG heavy chain (Fc) domain containing 2 single-chain antibodies against EMP2, a format that results in a longer plasma retention time. The constructs were expressed by transient transfection in HEK293E cells and purified to homogeneity. Flow cytometry and ELISA demonstrated binding properties of the fusion protein with high specificity and sensitivity to EMP2 expression. The enzymatic activity of the fusion construct was similar to commercially-available GrB. Internalization of the immunotoxins was confirmed, and they showed high cytotoxicity to EMP2-positive cells compared to EMP2-negative cells. We predict that these designs may improve therapeutic outcomes for EMP2+ tumors.
Citation Format: Khalid Mohamedali, Su-Yin Kok, Lawrence H. Cheung, Michael G. Rosenblum, Madhuri Wadehra. EMP2 serves as a novel target for immunotoxin mediated ovarian cancer 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 1218.
Abstract 1219: Generation of anti-OX40 antibody with different immunization strategies
Authors: Chai Xiaojuan , Xin Wenfang , Yang Teddy , Duan Qing , Liu Louis 
Published: August 2019

Abstract
Variety of immunogen such as recombinant protein, DNA or cells has been used for animal immunization to develop hybridoma antibody. However, the effectiveness among different types of immunogen in generating functional antibodies especially antibody with agonistic activity has not been systematically investigated.
OX40 (CD134) is a T cell costimulatory receptor that is found primarily on activated CD4+ and CD8+ T cells, regulatory T (Treg) cells and natural killer (NK) cells. Activation of OX40 by its natural ligand or an agonist antibody augments CD4 and CD8 T cell expansion, differentiation, and survival. Agonistic anti-OX40 antibody holds promise as therapeutics for cancer immunotherapy.
In the present study, different immunization strategies (recombinant protein, cell and DNA) have been used to generate anti-OX40 antibody. Antigen specific immune response, number of binders, epitope bins and the functional activities obtained from different immunogens were analyzed and compared. Based on cross reactivity and cell based functional assay results, 25 clones from protein immunization, 22 from DNA immunization and 29 from cell based immunization were expanded and purified. Among the purified antibodies, antibodies obtained from DNA immunization showed stronger agonist activity in both Jurkat OX40-NFAT luciferase reporter activity and primary T cell activation assay. The antibodies obtained from DNA immunization also demonstrated in vivo efficacy and significantly inhibited tumor growth in MC38 syngeneic mouse model using human OX-40 knock-in mice.
In summary, we have evaluated different immunization strategies using OX-40 as a case study and successfully generated high potency high affinity agonistic anti-OX40 antibody that support further development.
Citation Format: Xiaojuan Chai, Wenfang Xin, Teddy Yang, Qing Duan, Louis Liu. Generation of anti-OX40 antibody with different immunization strategies [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 1219.
Abstract 1221: Mitomycin C induces programed cell death ligand 1 overexpression but enhances anticancer immunity in none small cell lung cancer
Authors: Luo Min 
Published: August 2019

Abstract
Blockade of the checkpoint inhibitor programmed death 1 ligand (PDL1) has demonstrated remarkable success in the clinic for the treatment of cancer; however, a majority of tumors are progressive with low response rate. To enhance the efficacy of PDL1 blockade immunotherapies, we tried to combine chemotherapy capable of enhancing antitumor immunity. Here, we screened that tumor cells with MMC pre-treatment was significantly killed by co-cultured lymphocytes than without ones. Indeed, tumor cells treated with MMC showed the increased release of granzyme B and TNF-α. And tumor lysis was enhanced by combined with PD1 Ab in vitro. Mice treated with both anti-PDL1 and MMC showed an improved overall survival and inhibition within the tumor, indicating that this combination improves the overall quality of the immune response generated. Mechanically, MMC was observed to upregulate PDL1 expression in a concentration and time manner. MMC activated c-JUN to bind with PDL1 promoter and recruited its co-factor, STAT3 to accelerate PDL1 expression. MMC induced an IFN-γ independent signature within the tumor cell, and ERK signaling pathway was activated. A reason for its enhancement in antitumor immunity was the high expression of MHC-I after MMC treatment which attracted more CD8+ T cells. These findings identified a potential mechanism for the observed benefit of combining MMC and PDL1 blockade, in which MMC induces PDL1 upregulation and MCH-I high expression, thereby converting the tumor cell into an immunogenic one, when block PDL1, the antitumor response was enhanced.
Citation Format: Min Luo. Mitomycin C induces programed cell death ligand 1 overexpression but enhances anticancer immunity in none 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 1221.
Abstract 1223: Somatic mutations in collagens impact patient outcomes in cancer
Authors: Brodsky Alexander S. , Khurana Jay , Yang Dongfang , Gamsiz Ece , Wong Ian , Resnick Murray 
Published: August 2019

Abstract
Stomach cancer remains among the most lethal diseases around the world demanding improved treatments. The tumor microenvironment (TME) is a critical driver of tumor
progression and response to therapy and mediates many of the cancer hallmarks. Collagens are major components of the TME that controls disease progression and mediate therapeutic response. Collagens have been associated with stiffening of the tumor stroma, malignancy and therapeutic resistance. Collagenopathies are caused by loss of function collagen mutations that disrupt tissue formation and are dominant negative variants. We have found somatic tumor variants in collagens that are similar loss-of-function mutations as the germline variants observed in collagenopathies, providing guidance to interpret these cancer mutations. Indeed, the role of somatic mutations in collagens has not been addressed. Remarkably, we found multiple independent lines of evidence that collagen variants impact stomach adenocarcinoma tumors, consistent with a model that collagen variants disrupt the extracellular matrix (ECM) leading to improved therapeutic responses. 1) We find that loss-of-function collagen missense and nonsense mutations are associated with improved survival and disease-free progression times in gastric tumors in the TCGA dataset. 2) The same type of mutations observed in cancer are known to cause rare human diseases and therefore have the potential to impact cell function. 3) Independent of the patient outcome data, collagen variants were associated with significant changes in expression of tumor environment factors including ECM glycoproteins and EMT expression signatures. 4) Remapping RNA-seq reads reveals that single nucleotide variants of the collagens, matching the exome sequencing data are expressed. We will present computational and functional data supporting the hypothesis that somatic variants impact gastric tumors as well as analysis of the impact of collagens somatic mutations PanCancer. Somatic mutations in collagens represent a new paradigm for how cancer cells mediate the TME providing new biomarker and therapeutic opportunities to disrupt the ECM and improve outcomes for cancer patients.
Citation Format: Alexander S. Brodsky, Jay Khurana, Dongfang Yang, Ece Gamsiz, Ian Wong, Murray Resnick. Somatic mutations in collagens impact patient outcomes in 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 1223.
Abstract 1224: Correlation of tumor angiogenesis with peripheral ring-enhancement on CT: Its predictive value of chemotherapy responses of colorectal metastatic hepatic tumor
Authors: Okamoto Hirotaka , Shiba Shugo , Iino Hiroshi , Sudoh Makoto , Wakana Hiroyuki , Maruyama Suguru , Kawashima Kenji , Fukasawa Toshio , Ichikawa Daisuke , Fujii Hideki 
Published: August 2019

Abstract
[Background]The treatment of colorectal cancer (CRC) with metastasis is now widely accepted to be systemic chemotherapy of 5-FU base chemotherapy (FOLFOX or FOLFILI) in combination with molecular antibody. The objective of this study was to determine the significance of tumor angiogenesis in metastatic hepatic tumors in relation to the response of systemic chemotherapy.
[Methods]A total of 48 consecutive CRC patients with hepatic metastasis who had been treated with or without hepatic resection were retrospectively reviewed, and factors, such as metastatic tumor angiogenesis and chemotherapy response, were analyzed. Tumor angiogenesis in association with ring-enhancement (RE) on computed tomography (CT) was also microscopically evaluated by microvessel counting (MVD) in sections stained immunochemically with CD34.
[Results]The overall response rate after 6 courses of first-line chemotherapy for the liver metastasis with RE on CT was 64% (23/36), whereas the response rate without RE was 25% (3/12), which was significantly different. The survival rate of patients with or without liver resection of all RE-positive tumors was not different, but the survival rate of patients with liver resection was longer than that of patients without liver resection for all RE-negative tumors. Microscopic examination revealed that peripheral RE on CT of the metastatic tumor was associated with tumor angiogenesis by MVD.
[Conclusions]The peripheral RE on CT of the metastatic hepatic tumor was associated with tumor angiogenesis and may predict chemotherapy response. A combination of liver resection with chemotherapy improves the survival of patients who have multiple hepatic metastasis.
Citation Format: Hirotaka Okamoto, Shugo Shiba, Hiroshi Iino, Makoto Sudoh, Hiroyuki Wakana, Suguru Maruyama, Kenji Kawashima, Toshio Fukasawa, Daisuke Ichikawa, Hideki Fujii. Correlation of tumor angiogenesis with peripheral ring-enhancement on CT: Its predictive value of chemotherapy responses of colorectal metastatic hepatic tumor [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 1224.
Abstract 1229: Neoadjuvant therapy alters collagen architecture of pancreatic cancer
Authors: Nakajima Kosei , Ino Yoshinori , Nara Sotoshi , Iwasaki Toshimitsu , Hiraoka Nobuyoshi 
Published: August 2019

Abstract
Treatment of pancreatic cancer remains clinically challenging and requires the novel therapeutic interventions to improve patient outcome. Neoadjuvant therapy i.e. preoperative treatments comprising chemotherapeutic agents with/without radiation offers down-staging and improvement of surgical resectability. Here, we report that neoadjuvant therapy alters collagen architecture of pancreatic cancer. Transcriptomic profiles of type 1 to type 28 collagens depicted changes of collagen composition due to neoadjuvant therapy. Immunohistochemically, the expressed area of collagen type 1, 3, 4, and 5 were significantly reduced post treatment. The bioinformatic approaches provided a comprehensive insight into treatment-induced matrix remodeling, which showed that Ephrin-A signaling and Ephrin-A5 appeared as a highly possible pathway and a crucial ligand. Ephrin-A5 co-localized with alpha-SMA(+) cancer-associated fibroblasts, whereby Ephrin-A5 have been implicated to synthesize collagens. The Ephrin-A5 positive cells significantly reduced after neoadjuvant therapy, also inversely correlated with tumor shrinkage rate. Using primary culture cells of cancer-associated fibroblasts, experimental exposure of radiation and chemotherapeutic agents suppressed the proliferation of cancer-associated fibroblasts, collagen synthesis and Ephrin-A5 expression. Thus, our studies demonstrate that neoadjuvant therapy down-regulates Ephrin-A5 expression, leading to a change of extracellular matrix structure. It should be a clinical concern of surgical handling when following resection.
Note: This abstract was not presented at the meeting.
Citation Format: Kosei Nakajima, Yoshinori Ino, Sotoshi Nara, Toshimitsu Iwasaki, Nobuyoshi Hiraoka. Neoadjuvant therapy alters collagen architecture of pancreatic 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 1229.
Abstract 1233: Myeloperoxidase (MPO) activity in myeloid-derived suppressor cells (MDSCs): effects on anticancer drug activity
Authors: Yalowich Jack C. , Kanagasabai Ragu , Netherby Colleen S. , Messmer Michelle N. , Abrams Scott I. 
Published: August 2019

Abstract
In cancer, suppression of host immunity is related, in part, to immature myeloid-derived suppressor cells (MDSCs) expanded in response to various tumor- or stroma-derived factors. Here, the expression and activity of myeloperoxidase (MPO) was examined in both granulocytic (PMN) and monocytic (M) MDSC subsets recovered from the spleens of 4T1 tumor-bearing mice, as well as interferon regulatory factor-8 (IRF8) knockout mice (IRF8-/-) which develop high levels of MDSCs due to IRF8-deficiency. Phenotypically identical cells from non-tumor-bearing mice served as controls. In addition, the role of MPO in PMN-MDSCs as a determinant of DNA damage induced by the anticancer agents etoposide (VP-16), camptothecin (CPT) and parthenolide (PTL), was evaluated for potential immunomodulatory effects. MPO protein content was ~4-fold greater in PMN-MDSCs from tumor-bearing compared to non-tumor-bearing mice, while MPO specific activity was equivalent in these two populations. MPO protein content in PMN-MDSCs from IRF8-/- mice was at least comparable to levels found in tumor-bearing hosts. In both IRF8-/- and tumor-bearing mice, PMN-MDSCs contained 5-10-fold greater MPO protein and overall enzyme activity compared to isolated M-MDSCs. VP-16 (5 µM)- and PTL (100 µM)-induced DNA strand breaks were 4-fold greater in PMN- compared to M-MDSCs from tumor-bearing mice. In addition, the heme-synthesis inhibitor, succinylacetone (SA) reduced MPO activity 2-3-fold in PMN-MDSCs from tumor-bearing mice with a corresponding decrease in drug-induced DNA damage for both VP-16 and PTL with no effect on CPT-induced DNA damage. The antioxidant dehydroascorbate decreased VP-16-induced DNA damage in PMN-MDSCs containing MPO activity, but not in those cells pre-incubated with SA to deplete MPO. These results indicate that MPO-dependent activation of VP-16 and PTL enhance DNA damage. Antioxidant protection against VP-16-induced DNA damage is consistent with MPO-mediated oxidative activation of VP-16 to a redox-cycling phenoxyl radical (Mol. Pharmacol. 79: 479-487, 2011). Overall, these results suggest that: 1) PTL may be useful to eliminate PMN-MDSCs; 2) MPO activation of VP-16 in PMN-MDSCs may be deleterious via oxidative DNA damage resulting in mixed-lineage leukemia (MLL) gene rearrangements known to be causal for therapy-related myeloid leukemias. Support: CA172105; CA090787; CA140622
Citation Format: Jack C. Yalowich, Ragu Kanagasabai, Colleen S. Netherby, Michelle N. Messmer, Scott I. Abrams. Myeloperoxidase (MPO) activity in myeloid-derived suppressor cells (MDSCs): effects on anticancer drug activity [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 1233.
Abstract 1235: Targeting RNA-binding protein HuR to inhibit human breast cancer invasion and metastasis
Authors: Wu Xiaoqing , Gardashova Gulhumay , Lan Lan , Han Shuang , Zhong Cuncong , Gowthaman Ragul , Karanicolas John , Dixon Dan A. , Welch Danny R. , Li Ling , Ji Min , Aubé Jeffrey , Xu Liang 
Published: August 2019

Abstract
The majority of breast cancer-related mortality is due to metastasis. Patients diagnosed with metastatic breast cancer have a dismal 5-year survival rate of only 24%. The RNA-binding protein Hu antigen R (HuR) is overexpressed in breast cancer. Cytoplasmic HuR accumulation correlates with high-grade malignancy, poor distant disease-free survival and serves as a prognostic factor for poor clinical outcome in breast cancer. HuR promotes tumorigenesis by regulating numerous proto-oncogenes, growth factors and cytokines that implicate major tumor hallmarks including invasion and metastasis. Knocking out HuR by CRISPR/CAS9 technology inhibits cell invasion in breast cancer cells. Therefore, HuR is an emerging target for breast cancer therapy, especially the lethal metastatic breast cancer. RNA-binding proteins had previously been considered “undruggable” due to lack of a well-defined binding pocket for target RNAs. Using high throughput screening followed by structure-based rational design and lead optimization, we have identified small molecules that inhibit HuR-mRNA interaction at nM to sub-µM potency. Our lead compound, KH-3, potently inhibits breast cancer cell growth and decreases cell invasion in vitro similar to HuR knockout, as well as increasing the expression of epithelial marker E-cadherin. In the study of mechanism of action, a transcription factor, FOXQ1, which is recently revealed to implicate in breast cancer invasion and metastasis processes, is found for the first time to be a direct mRNA target of HuR and one of the top genes that are reduced by KH-3 treatment. Exogenous introduction of FOXQ1 can rescue cell invasive capability impaired by HuR knockout and abolish the effect of KH-3 on inhibiting cell invasion in breast cancer cells. Moreover, KH-3 disrupts HuR-FOXQ1 interaction in RNP-IP, RNA pull down and FOXQ1 3′-UTR luciferase reporter assays. In vivo efficacy studies show that KH-3 not only exhibits potent antitumor efficacy in an orthotopic xenograft model of breast cancer, but also efficiently inhibits lung metastasis and improves mouse survival in an experimental metastasis model. Our data provide a proof-of-principle that HuR inhibition by KH-3 may be developed as a promising molecular therapy for inhibiting progression and metastasis of breast cancer with high HuR.
Citation Format: Xiaoqing Wu, Gulhumay Gardashova, Lan Lan, Shuang Han, Cuncong Zhong, Ragul Gowthaman, John Karanicolas, Dan A. Dixon, Danny R. Welch, Ling Li, Min Ji, Jeffrey Aubé, Liang Xu. Targeting RNA-binding protein HuR to inhibit human breast cancer invasion and metastasis [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 1235.
Abstract 1236: Subclinical doses and choice of replication stress inducer in combination with CHK1 inhibitors for optimal tumor control and immune responses in vitro and in vivo
Authors: Oo Zay Yar , Proctor Martina , Stevenson Alex , Nazareth Deborah , Larsen Jill , Haass Nikolas , Gabrielli Brian G. 
Published: August 2019

Abstract
Background: Lung cancer and melanoma are responsible for almost 25% of cancer deaths in Australia. Despite recent progress with targeted and immuno-therapies, the 5 year survival rate in late stage patients is still&lt;20%. CHK1 inhibitors are being investigated as chemosensitizing agents with agents that increase replication stress, primarily Gemcitiabine. Clinical trials of this combination have shown some good responses but high levels of normal tissue toxicity.
Materials and methods: Here we have investigated the molecular basis of sensitivity to CHK1 inhibitors as combinations with subclinical doses of hydroxyurea (HU) in melanoma and non-small cell lung cancer (NSCLC) tumor spheres and cell lines in 2% O2 conditions and xenograft models in immune compromised mice and with humanized immune systems.
Results: We report that low dose HU increased the sensitivity of &gt;70% of both melanoma and NSCLC cell lines to CHK1 inhibitor (GDC-0575) triggered apoptosis, with complete loss of viability found with clinically achievable doses of this combination. Similar sensitivity was observed in xenograft models of both melanoma and NSCLC. We also demonstrate that a low dose of Gemcitabine combination with CHK1 inhibitor results in complete loss of proliferative potential in normal tissue, whereas normal tissue retaining proliferative potential after treatment with even high doses of hydroxyurea in combination with CHK1 inhibitor. In vivo, this translates to minimal effect on lymphocyte populations in the blood. The combination also triggers an inflammatory response involving the recruitment of macrophages, associated with increased HMGB1 nuclear staining. Immune responses were also assessed in humanized mouse models.
Discussion: These data indicate that the combination of low dose HU and CHK1 inhibitor have strong anti-cancer activity in the setting of melanoma and NSCLC cancer, and triggers an inflammatory response, and is likely to be better tolerated than current combinations with Gemcitabine. Our data suggest a significant proportion of melanoma and lung cancer patients could benefit from treatment with this drug combination, and this appears to include an immune response to the tumor.
Citation Format: Zay Yar Oo, Martina Proctor, Alex Stevenson, Deborah Nazareth, Jill Larsen, Nikolas Haass, Brian G. Gabrielli. Subclinical doses and choice of replication stress inducer in combination with CHK1 inhibitors for optimal tumor control and immune responses in vitro and in vivo [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 1236.