bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 2571: DBC1, a novel CBP-interacting protein, promotes p53 stability by regulating CBP-dependent p53 polyubiquitination
Authors: Akande Oluwatoyin E. , Damle Priyadarshan K. , Sherman Nicholas E. , Grossman Steven R.
Published: July 2017

The acetyltransferase CBP, in conjunction with the E3 ubiquitin ligase enzyme, Mdm2, maintains physiologic levels of the tumor suppressor protein p53 in the absence of cellular stress, via a cytoplasmic, but not nuclear, p53-directed E4 polyubiquitin activity. CBP also possesses cytoplasmic, but not nuclear, E3 ubiquitin ligase, autoubiquitination activity. To understand the mechanism by which the ubiquitin ligase activities of CBP are compartmentalized in the cell, we have employed Multidimensional Protein Identification Technology (MudPIT) to identify cytoplasmic and nuclear CBP interacting proteins. MudPIT analysis revealed that Cell Cycle and Apoptosis Regulator protein (CCAR2), also known as Deleted in Breast Cancer 1 protein (DBC1), is a novel CBP- interacting protein in both the nucleus and cytoplasm. The N-terminus of DBC1 bound to multiple CBP domains, including the putative E3/E4 domain of CBP located at the N-terminus. Interaction between DBC1 and CBP suppressed the in vitro E3 autoubiquitination activity of CBP. Functional studies demonstrated that DBC1 directly regulates the cellular compartmentalization of CBP E3 and p53-directed E4 ubiquitin ligase activities. Knockdown of DBC1 in U2OS cells stimulated normally absent nuclear p53 polyubiquitination, and also caused a decrease in p53-dependent and p53-independent apoptosis, rescued by CBP/DBC1 double knockdown. Further, over-expression of DBC1 rescued the increase in nuclear p53 polyubiquitination and decrease in p53 half-life observed in DBC1 depleted cells. Together, these results identify DBC1 as a novel binding partner of CBP and a critical regulator of CBP ubiquitin ligase activities. Based on our data that DBC1 loss inactivates p53 function through destabilization, we queried the TCGA database for co-occurrence of DBC1 loss with maintenance of wild-type p53 status which showed that 33% of breast, 40% of lung, and 96% of prostate cancer cases with DBC1 alterations maintained wild-type p53 status. Therefore, by restoring DBC1 function, this work could lead to reactivation of p53 tumor suppressor activity in tumors with DBC1 alterations maintaining wild-type p53 status.

Citation Format: Oluwatoyin E. Akande, Priyadarshan K. Damle, Nicholas E. Sherman, Steven R. Grossman. DBC1, a novel CBP-interacting protein, promotes p53 stability by regulating CBP-dependent p53 polyubiquitination [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2571. doi:10.1158/1538-7445.AM2017-2571
Abstract 2573: TP73's regulation and expression in human cancer cell lines
Authors: Yao Zhixing , Yao David R. , Yu William , Brim Hassan , Ashktorab Hassan , Sherif Zaki A.
Published: July 2017

TP73 is the homologue of the master tumor suppressor TP53. It is involved in cellular responses to stress and development. The TP73 gene encodes two different proteins, TAp73 and ΔNp73 and maps to a region on chromosome 1p36 that is frequently deleted in neuroblastoma and other tumors, and thought to contain multiple tumor suppressor genes. However, the analysis of p73-knockout mice yielded conflicting results with respect to tumor suppression. World-wide efforts in sequencing the TP73 gene in patient tumor samples have not provided evidence for genetic alterations as a common cause of p73 inactivation in human cancer. The role of TP73 in tumorigenesis has remained elusive to date. In this study, we isolated two stem cell lines from normal young and old human liver tissues and determined TP73 expression in human breast cancer cell lines (MCF7 & MDA321), human hepatocellular carcinoma (HCC) cell lines (HepG2, SNU398, SNU449 & SNU475), neuroblastoma cell lines (IMR32 & SK-N-SH), normal liver stem cell, non-cancerous Li-Fraumeni Syndrome (LFS) skin fibroblasts cells and normal skin fibroblasts. Results show that TAp73 only expresses in cancer cell lines. Moreover, when HepG2 and MDA231 were treated with paclitaxel, a cytoskeletal drug that targets tubulin, TAp73 expression was drastically down-regulated in HepG2 cells and abrogated in MDA231 cells at 1 to 5 µmol/L concentrations. Furthermore, ChIP assay results demonstrated that TP53 and CTCF (a chromosomal networking protein CCCTC binding factor) bind to TP73 promoter and regulate TP73 expression. Our observation may prove significant for the development of future therapeutic and diagnostic applications.

*These authors contributed equally to this work.

Citation Format: Zhixing Yao, David R. Yao, William Yu, Hassan Brim, Hassan Ashktorab, Zaki A. Sherif. TP73's regulation and expression in human cancer cell lines [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2573. doi:10.1158/1538-7445.AM2017-2573
Abstract 2579: Identifying pathways that regulate the turnover of gain-of-function p53 mutant proteins in ovarian cancer cells
Authors: Padmanabhan Achuth , Candelaria Nicholes , Wong Kwong-Kwok , Nikolai Bryan C. , Lonard David , O'Malley Bert W. , Richards JoAnne S.
Published: July 2017

Ovarian cancer is the fifth leading cause for cancer-associated deaths among women in the US. High-grade serous ovarian carcinoma is the most common histological subtype and is characterized by frequent (>90%) mutations in the TP53 (p53) gene. Gain-of-function (GOF) p53 mutant proteins form highly stable aggregates that accumulate in ovarian cancer cells and have been shown to have oncogenic activity. Increasing evidence indicates the stabilization of GOF p53 mutants to be important for tumor progression and drug resistance. Therefore, selective degradation of the GOF p53 mutant proteins is a highly attractive therapeutic strategy to specifically target ovarian cancer cells. We identified that a small molecule named MCB-613, originally discovered as a stimulator of steroid receptor coactivator-3 (SRC-3), causes rapid degradation of the usually stable p53R175H conformational mutant aggregates leading to catastrophic cell death in human ovarian cancer cell lines. Our results indicate this effect is independent of SRC-3 mediated gene expression, but rather by post-translational modification of p53 mutant protein. Upon MCB-613 treatment, the p53R175H mutant is rapidly exported from the nucleus, ubiquitinated and degraded through a lysosomal pathway. Interestingly, in contrast to its effect on the p53R175H mutant, MCB-613 causes a slight stabilization of wild type (WT) p53 but had less of an effect on the turnover of other frequently observed p53 mutants (R248Q and R273H) in human ovarian cancer cell lines. MCB-613 also causes a rapid decrease in MDM2 protein but not mRNA. Further, the effect of MCB-613 on p53R175H is phenocopied by multiple deubiquitinase (DUB) inhibitors, confirming the role of ubiquitination in the selective turnover of p53R175H mutant aggregates. Taken together, these results show that different pathways regulate the turnover of WT p53 and the specific GOF p53 mutant proteins. We are currently investigating the precise mechanism by which MCB-613 and the different DUB inhibitors induce selective turnover of p53R175H mutant protein. We anticipate the proposed work to significantly advance our understanding of pathways important in ovarian cancer progression and pave way for the development of new targeted therapies for ovarian cancer patients with specific p53 mutations. This work is funded by NIH-CA-181808, NIH-HD-07857 and NIH-HD-076596.

Citation Format: Achuth Padmanabhan, Nicholes Candelaria, Kwong-Kwok Wong, Bryan C. Nikolai, David Lonard, Bert W. O'Malley, JoAnne S. Richards. Identifying pathways that regulate the turnover of gain-of-function p53 mutant proteins in ovarian cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2579. doi:10.1158/1538-7445.AM2017-2579
Abstract 2598: Paradigm to ensure curation transparency and consistency of a cancer genomic database - the JAX Clinical Knowledgebase (CKB)
Authors: Yin Taofei , Patterson Sara E. , Statz Cara M. , Lakshminarayana Anuradha , Durkin Daniel , Mockus Susan M.
Published: July 2017

In the era of personalized medicine, comprehensive cancer genomic databases represent critical tools for interpreting gene variants and their relevant therapies. As the number of cancer genomic databases grow, it is challenging for users to compare and assess the data integrity and validity of such databases. The lack of disclosure of curation processes makes it difficult to cross reference different databases. The JAX Clinical Knowledgebase (CKB) is a comprehensive relational database providing evidence-based information on gene variants, targeted therapies, efficacy evidence, and clinical trials. At the Jackson Laboratory for Genomic Medicine, we have developed a curation paradigm to ensure curation transparency and consistency of the JAX-CKB. First, to ensure standardization of nomenclature, we have integrated standard nomenclature and ontologies, including HGNC approved nomenclatures for genes, HGVS guidelines for variants, and the Disease Ontology for indications/tumor types. Second, we implemented decision matrices to maintain uniformity of our evaluation of scientific and clinical data. For example, evaluation of the effect of gene variants on protein function is solely based on changes in the intrinsic activity of the protein instead of downstream pathway activation or the effects on pathogenesis; the response type of gene variants to therapies are classified based on the evidence of targeting specificity; and the efficacy evidence are further classified as actionable, diagnostic, prognostic, risk factor, emerging, or not active centered on the response type and the strength of the evidence. Third, to provide convenient evaluation of the clinical relevance of efficacy data, we further developed a tier ranking system based on emerging consensus guidelines, which takes response type, evidence type, and approval status into consideration. Finally, all decision matrices are clearly outlined on the JAX-CKB open access website for users’ reference. In summary, we have curated a highly structured and semantically consistent cancer genomic database following a set of specific curation guidelines. As a result, JAX-CKB open access has become a valuable resource for both the clinical and research communities, and is utilized by numerous independent groups for variant interpretation.

Citation Format: Taofei Yin, Sara E. Patterson, Cara M. Statz, Anuradha Lakshminarayana, Daniel Durkin, Susan M. Mockus. Paradigm to ensure curation transparency and consistency of a cancer genomic database - the JAX Clinical Knowledgebase (CKB) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2598. doi:10.1158/1538-7445.AM2017-2598
Abstract 2600: Analysis of drug resistance mechanisms and strategies for overcoming resistance in cancer therapy using a curated clinical knowledgebase
Authors: Patterson Sara E. , Statz Cara M. , Yin Taofei , Mockus Susan M.
Published: July 2017

Emergence of resistance to targeted therapies is a critical problem in cancer therapy, and understanding both the mechanisms of resistance and strategies for overcoming resistance are crucial to effective treatment of cancer patients. The JAX Clinical Knowledgebase (JAX-CKB), which incorporates data on therapeutic efficacy in the context of molecular alterations, enables rapid analysis of known therapy resistance mechanisms and current data surrounding strategies for overcoming resistance, both in the preclinical and clinical setting. Using the JAX-CKB, we have identified over 1250 lines of evidence corresponding to therapy resistance across tumor types. Of those lines, 147 correspond to therapy resistance in lung cancer. The JAX-CKB contains 22 variants in ALK associated with ALK therapy resistance. Within ALK fusion-positive lung cancer, evidence lines corresponding to ALK inhibitor resistance are associated primarily with complex molecular profiles containing secondary ALK mutations, and mechanisms for overcoming resistance in this setting were associated with use of novel agents. Within EGFR mutation positive lung cancer, lines associated with resistance to EGFR inhibitor therapy included copy number alterations, primary resistance mutations, secondary resistance mutations, and expression level changes. Strategies for overcoming resistance in these settings include novel agents and/or various combination therapies. The JAX-CKB provides a unique global view into current data on resistance to targeted therapies in oncology, which may enable more rapid assessment of effective therapy options and expose opportunities for additional research into strategies for overcoming resistance.

Citation Format: Sara E. Patterson, Cara M. Statz, Taofei Yin, Susan M. Mockus. Analysis of drug resistance mechanisms and strategies for overcoming resistance in cancer therapy using a curated clinical knowledgebase [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2600. doi:10.1158/1538-7445.AM2017-2600
Abstract 2606: Accelerating clinical research using cloud technology
Authors: Apte Arun , Paul Shonali , Gade Aditi , Compton Carolyn
Published: July 2017

Introduction: Existing protocols for clinical trials are typically slow and error-prone due to lack of informatics tools for sharing and accessing clinical data in real time. There is an increasing pressure on clinical trial laboratories to change the way clinical research is performed so as to minimize costs and speed up R&D, which in turn will produce better and faster outcomes. Cloud-based technologies are emerging as one of the most viable options for streamlining the heavily regulated clinical research processes.

Description: Cloud-based software tools such as laboratory information management systems (LIMS) are much more capable than traditional paper-based or desktop tools for accelerating a clinical trial life cycle. Cloud-based LIMS enhance collaboration between sponsors and investigators, enabling more timely and accurate sharing of information with pharmaceutical companies.

Summary: Many sponsors are now adopting cloud-based LIMS for conducting clinical trials. The onus is on service providers to keep pace with the demands of the industry, comply with the regulatory framework and at the same time deliver value to CROs and testing labs by reducing costs and maintaining efficiency.

Conclusion: CloudLIMS.com has developed a cloud based software called CloudLIMS Lite for managing clinical research workflows to provide a cost effective solution to the clinical research industry. Being on the cloud, CloudLIMS Lite facilitates users to access and share data in real time, across multiple laboratories in different geographical locations and adhere to the regulatory framework. This in turn improves their operational efficiency. CloudLIMS Lite uses 256-bit AES encryption SSL protocol, thereby enabling secure data transmission. CloudLIMS Lite deploys a separate database layer for each of its customers making it impossible for any third party to view or access data.

Citation Format: Arun Apte, Shonali Paul, Aditi Gade, Carolyn Compton. Accelerating clinical research using cloud technology [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2606. doi:10.1158/1538-7445.AM2017-2606
Abstract 2637: Anti-tumor activity of cisplatin is enhanced by PD-1 blockade in preclinical models of head and neck squamous cell carcinoma
Authors: Tran Linda , Allen Clint T. , Park So-Jin , Xiao Roy , Waes Carter Van , Schmitt Nicole C.
Published: July 2017

Rationale: Cisplatin, which remains the most commonly used systemic drug for head and neck squamous cell carcinoma (HNSCC), reduces numbers of circulating immune cells. However, recent studies suggest that cisplatin may enhance some aspects of anti-tumor immunity in the tumor microenvironment. We previously found that cisplatin increases expression of major histocompatibility (MHC) class I and programmed death ligand 1 (PD-L1) in HNSCC cell lines in vitro.

Methods: In the current study, we investigated other components of the antigen processing machinery (APM) by flow cytometry following treatment with cisplatin. Using the syngeneic mouse oral cancer 1 (MOC1) model of HNSCC, we then investigated the effects of cisplatin and anti-PD-1 antibody, alone or in combination, on tumor growth and survival.

Results: Using three different HNSCC cell lines, we found that levels of the APM components LMP2, ERp57 and calreticulin increased in all cell lines treated with cisplatin, whereas TAP1/2 increased dramatically only in one cisplatin-treated cell line with wildtype TP53 (UMSCC-74A). In MOC1 tumor-bearing mice, tumor growth was partially delayed by treatment with cisplatin and anti-PD-1 antibody alone and substantially delayed when these agents were given in combination, with resultant increased survival. Comparison of different treatment schedules suggested that concurrent administration is more effective than giving cisplatin one day prior to anti-PD-1 or giving anti-PD-1 one day prior to cisplatin.

Conclusions: Despite upregulating PD-L1 on tumor cells and decreasing levels of circulating immune cells, cisplatin may enhance some aspects of anti-tumor immunity in the tumor microenvironment. While no mice were cured with concurrent cisplatin and anti-PD-1 antibody, tumor growth was substantially delayed. These results suggest a rationale for combining cisplatin and anti-PD-1 monoclonal antibodies, perhaps with radiation or other therapies, in additional preclinical studies and clinical trials of HNSCC.

Supported by NIDCD intramural project ZIA-DC-DC000090.

Citation Format: Linda Tran, Clint T. Allen, So-Jin Park, Roy Xiao, Carter Van Waes, Nicole C. Schmitt. Anti-tumor activity of cisplatin is enhanced by PD-1 blockade in preclinical models of head and neck squamous cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2637. doi:10.1158/1538-7445.AM2017-2637
Abstract 2638: Clinical characteristics and PD-L1 expression of pulmonary sarcomatoid carcinoma
Authors: Lee Sung Yong , Shim Jae Kyeom , Oh Jee Youn , Min Kyung Hoon , Hur Gyu Young , Shim Jae Jeong , Kang Kyung Ho , Shin Bong Kyung , Lee Young Seok
Published: July 2017

Introduction: Pulmonary sarcomatoid carcinoma (PSC) is a poorly differentiated non-small cell lung cancer (NSCLC) containing a component of spindle cell or giant cell. Because the prevalence of PSC is very rare, there is insufficient data about clinical feature, therapeutic strategy and prognosis.

Method: We reviewed the medical records of 26 patients diagnosed with PSC from January 2009 to June 2015, and analyzed the clincopathological characteristics, treatment modality and their outcome, and risk factors of overall survival (OS). Programmed death ligand 1 (PD-L1) expression was tested in 13 patients by using archival tissues (PD-L1 IHC 22C3 pharmDx assay).

Results: The median age of PSC patients was 69.5 years. 23 patients were male. 25 patients were current or former heavy smokers. Pleomorphic carcinoma was the most common subtype, and epidermal growth receptor mutation (EGFR) was positive in 2 of 11 patients who were tested. Among 13 patients tested for programmed death ligand 1 (PD-L1), eight showed PD-L1 high expression (tumor proportion score, TPS ≥ 50%). Four patients showed low expression (1% ≤ TPS ≤ 49%), and one patient showed no expression (TPS < 1%). The median OS of all patients was 286 days. Age and the time from symptom onset to diagnosis were significantly associated with OS. PD-L1 expression showed the trend of positive prognostic value on OS in univariate analysis but was insignificant in multivariate analysis. 12 patients were treated with chemotherapy: 9 with platinum-based doublet therapy, 2 with tyrosine kinase inhibitor and 1 with docetaxel. 7 patients showed partial response or stable disease. The median OS and progression free survival of patients receiving chemotherapy were 260 days and 85 days, respectively.

Conclusions: It has poor prognosis compared with ordinary NSCLC. However, PSC patients showed comparatively fair response to chemotherapy and generally showed higher PD-L1 expression. Active treatment with cytotoxic chemotherapy, EGFR TKIs or immune checkpoint inhibitors are necessary to achieve a better results of PSC management.

Citation Format: Sung Yong Lee, Jae Kyeom Shim, Jee Youn Oh, Kyung Hoon Min, Gyu Young Hur, Jae Jeong Shim, Kyung Ho Kang, Bong Kyung Shin, Young Seok Lee. Clinical characteristics and PD-L1 expression of pulmonary sarcomatoid carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2638. doi:10.1158/1538-7445.AM2017-2638
Abstract 2654: Resveratrol and piceatannol synergistically induce PDL1 expression
Authors: Lucas Justin P. , Wu Joseph M. , Hsieh TzeChen , Darzynkiewicz Zbigniew , Halicka-Ambroziak Halina Dorota
Published: July 2017

The interaction of programmed cell death-1 (PD-1) and its ligand programed cell death-1 ligand (PD-L1) is a major focus of recent immune oncology therapy efforts. The expression of PD-1 on T lymphocytes and its subsequent interaction with PD-L1, either from antigen presenting or tumor cells, will result in apoptosis-dependent inactivation of the T lymphocytes. This interaction plays an integral role in tumor immunology, specifically augmenting immune evasion. Relatively little is known about the regulation of PD-L1 in either the tumor or normal environment. We investigated the ability of natural dietary compounds to induce PD-L1 expression on normal epithelial cells and various cancer cell lines. These molecules have been evolutionary selected to control inflammation and cancer cell transformation and progression, understanding their mechanism of action could be important to understanding how this system works. Using flow cytometry and immunohistochemistry, we focused our studies on resveratrol and its metabolite piceatannol, key phytochemicals extracted from grapes, after an initial screen of various natural products. Experimental data showed that both compounds can individually up-regulate the expression of PD-L1 on tumor cell lines and normal epithelial cells, by an IFN-γ-independent mechanism. PD-L1 induction by both of these compounds was higher in tumor than in normal epithelium, suggesting greater significance in tumor regulation than inflammation. Additionally, the combination of resveratrol and piceatannol acted synergistically, leading to a significantly greater induction of PD-L1 expression across multiple tumor indications. Understanding whether resveratrol and piceatannol use a common signaling pathway to induce PD-L1 expression in tumor cells, was critical to understand the synergistic induction observed. Studies utilizing specific inhibition of IKK phosphorylation were accompanied by a significant reduction in the ability to induce PD-L1 expression on tumor cells, either as single agents or in combination. These results are consistent with the hypothesis that induction of PD-L1 by resveratrol or piceatannol, or their combination involves molecular determinants down-stream of NF-kB signaling.

Citation Format: Justin P. Lucas, Joseph M. Wu, TzeChen Hsieh, Zbigniew Darzynkiewicz, Halina Dorota Halicka-Ambroziak. Resveratrol and piceatannol synergistically induce PDL1 expression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2654. doi:10.1158/1538-7445.AM2017-2654
Abstract 2661: A broad approach for the selection of therapeutic mAbs to TNFR-superfamily members for use in combination with an anti-PD-1 mAb
Authors: Chen Cheng , Miao Xiaoniu , Yan Yao , Tang Liang , Chen Bingliang , Liu Junjian , Liu Xiaolin , Yu Michael , Tsun Andy
Published: July 2017

The rise of therapeutic antibodies directed towards T cell checkpoint inhibitors has paved the way to a novel and exciting frontier of cancer treatments. Spearheaded by anti-CTLA-4 and PD-1/PD-L1 inhibitors, many investigators have strived to uncover combinatory therapies that could synergize with CTLA-4 and PD-1 inhibitors to improve the overall survival of cancer patients. The TNFR-superfamily has been seen as an ideal combinatory target in providing co-stimulatory T cell signals in sync with the unleashing of T cells from their CTLA-4 and PD-1 brakes. The ideal outcome of these combinations is the induction of T cell memory and effector function towards tumour cells. Current clinical-stage agents against TNFR-superfamily targets include conventional or Fc-engineered therapeutic antibodies and multimeric ligands that aim to cluster and activate targets such as OX40, 4-1BB, GITR, and CD27. For OX40 and GITR, wildtype IgG1 variants offer target cell depletion of OX40/GITR-high expressing Treg cells, and also provide agonism through FcgR-mediated crosslinking. We have taken a broad approach of screening IgG1, IgG2, Fc-engineered and tetravalent antibodies to select for potent therapeutic antibody candidates to TNFR-superfamily targets, and conducted humanized mouse studies as a screen for candidate potency.

Citation Format: Cheng Chen, Xiaoniu Miao, Yao Yan, Liang Tang, Bingliang Chen, Junjian Liu, Xiaolin Liu, Michael Yu, Andy Tsun. A broad approach for the selection of therapeutic mAbs to TNFR-superfamily members for use in combination with an anti-PD-1 mAb [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2661. doi:10.1158/1538-7445.AM2017-2661
Abstract 2662: Statins modulate MMP-9 and beta catenin in epithelial cells
Authors: Fazal Nadeem , Al-Ghoul Walid
Published: July 2017

The effect of statins (Simvastatins) mediated mechanisms that affect inflammatory or non-inflammatory pathways causing formation and progression of cancer need to be investigated. Currently, sufficient data are lacking to support the use of statins for the prevention of cancer and further research is clearly warranted. We studied these antineoplastic mechanisms in rodent inflammatory model, which might be instrumental in drug discovery research for the development of future cancer therapeutics. MMP9 is a member of the family of zinc-containing endopeptidases, which degrade various components of the extracellular matrix, thereby regulating matrix remodeling. Since matrix remodeling plays an important role during growth and progression of cancer and considering the fact that, tumor cells switch to aerobic glycolysis as its major energy source, this study was designed to analyze the effect of Statins on MMP9 and epithelial cell integrity at gastrointestinal gut barrier. We used an established model of thermal injury (TI) to study the effects of simvastatins. We found that the percentage of stained MMP-9 in the control tissue and TI+SMV tissue was lower than the percentage in thermal injury tissue (P< 0.05). Moreover, fluorescent stained sections of intestinal epithelial from control, thermal injury and thermal injury+SMV. β-catenin determination was performed with fluorescence microscope. β-catenin levels were significantly (p<0.05) decreased in thermal injury tissue, which was reversed by statins. Our studies conclude that statins have anti-neoplastic effects and affect metallopeptidases, β-catenin and e-cadherins.

Note: This abstract was not presented at the meeting.

Citation Format: Nadeem Fazal, Walid Al-Ghoul. Statins modulate MMP-9 and beta catenin in epithelial cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2662. doi:10.1158/1538-7445.AM2017-2662
Abstract 2668: Efficacy study of immuno-checkpoint antibodies in humanized CDX and PDX models
Authors: Zhang Feifei , Yang Yang , Chen Hongkui , Jia Lijun , Ouyang Kedong , Wen Danyi , Chen Taiping
Published: July 2017

Immune therapeutic intervention has been accepted widely for many hematopoietic malignancies and solid malignancies in past several years. Preclinical animal models with reconstitution of immune cells and target-expressing tumor cells were urgently needed for prove of concept studies demonstrating stimulatory immune system activation. Here we describe two established models of human PBMC co-transplantation of CDX and PDX. The study design was based on co-inoculation of human PBMC and PD-L1 expressing cell in NOG mice for reconstitution of immuno-checkpoint blockage. A therapeutic anti-PD1 antibody was applied for immune system activation and tumor growth inhibition measurement. After drugs were administrated i.p. for three weeks, 95 % TGI for A375 CDX model were observed. At the termination of the efficacy study at 28 days post therapeutic intervention, tumors of vehicle (tumor only, PMBC only), PD1 Ab treated groups were collected for immunostaining of CD45. Infiltrating T-cell with CD45+ label was found within the tumors when co-inoculated with human PBMC. PBMC humanized PDX models of ovarian cancer was implanted into mice which reconstituted with human PBMC for therapeutic intervention. Results showed that 85% TGI for PBMC humanized ovarian PDX models was observed. In conclusion, the models established here are feasible for immunotherapeutic evaluation and further additional immune therapeutic test articles can be explored with similar approaches.

Citation Format: Feifei Zhang, Yang Yang, Hongkui Chen, Lijun Jia, Kedong Ouyang, Danyi Wen, Taiping Chen. Efficacy study of immuno-checkpoint antibodies in humanized CDX and PDX models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2668. doi:10.1158/1538-7445.AM2017-2668
Abstract 2670: Combination of anti-HER2 ADC XMT-1522 and checkpoint inhibitor pembrolizumab for treatment of NSCLC in preclinical models
Authors: Bodyak Natalya , Protopopova Marina , Zhang Qingxiu , Yurkovetskiy Alex , Yin Mao , Qin LiuLiang , Poling Laura L. , Mosher Rebecca , Bergstrom Donald A. , Lowinger Timothy B.
Published: July 2017

The combination of antibody-drug conjugates (ADCs) and immunomodulatory cancer therapies is emerging as a powerful strategy for cancer treatment. Tumor-targeted delivery of a cytotoxic payload capable of inducing immunogenic cell death (ICD) can trigger both an innate and an adaptive immune response, whereby increased recruitment of effector T-cells to the tumor and formation of tumor specific immunological memory can result in a durable treatment response. The ADC XMT-1522 consists of a novel human IgG1 anti-HER2 monoclonal antibody and a novel, auristatin-based cytotoxic payload (Auristatin F-hydroxypropylamide, AF-HPA). An average DAR of 12 AF-HPA molecules is achieved via a biodegradable polymer conjugation platform. We have characterized the ability of both the free payload AF-HPA and the ADC XMT-1522 to induce ICD in vitro in multiple cell lines (NCI-N87, HT-29, SKBR3), as measured by the cell surface expression of the ICD marker calreticulin (CRT) by microscopy and flow cytometry (FACS). CRT, usually contained in the lumen of the endoplasmic reticulum, translocated to the cell surface within a few hours after treatment with AF-HPA or XMT-1522. XMT-1522 as a single agent induced significant tumor regressions in two patient-derived xenograft (PDX) models of HER2-espressing non-small cell lung cancer (NSCLC) at a dose of 3 mg/kg weekly for 3 doses. The combination of XMT-1522 in combination with the checkpoint inhibitor pembrolizumab was tested in one of these patient-derived HER2-expressing PDX models in a mouse with a humanized immune system. Expression of huPD-L1 in the tumor was confirmed by FACS and immunohistochemistry (IHC). Lymphocyte sub-populations were quantified in whole blood and in tumor by FACS and IHC. XMT-1522 treatment alone induced tumor growth delay after 3 weekly doses of 1 mg/kg. Pembrolizumab as a single agent administered every 5 days for 6 doses (q5dx6) at a dose of 2.5 mg/kg led to less tumor growth delay than XMT-1522 treatment. The combination of these two treatment regimens resulted in a better response than either of the two monotherapies. These data provide a rationale for XMT-1522 to be tested clinically as a single agent in HER2-expressing NSCLC, as well as a rationale for combination of XMT-1522 and immunomodulatory therapies in NSCLC.

Citation Format: Natalya Bodyak, Marina Protopopova, Qingxiu Zhang, Alex Yurkovetskiy, Mao Yin, LiuLiang Qin, Laura L. Poling, Rebecca Mosher, Donald A. Bergstrom, Timothy B. Lowinger. Combination of anti-HER2 ADC XMT-1522 and checkpoint inhibitor pembrolizumab for treatment of NSCLC in preclinical models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2670. doi:10.1158/1538-7445.AM2017-2670
Abstract 2677: Role of CLEC4D in inflammation-driven liver carcinogenesis
Authors: Riboldi Elena , Tommaso Luca Di , Clemente Nausicaa , Raggi Chiara , Forti Elisa , Merlin Simone , Pasqualini Fabio , Follenzi Antonia , Sica Antonio
Published: July 2017

Hepatocellular carcinoma (HCC) accounts for approximately 90% of all primary liver tumors and is the second most deadly cancer in the world. HCC commonly arises in a chronically damaged liver that contains large amounts of inflammation and fibrosis. Indeed, interactions among hepatocytes, stromal, and inflammatory cells create a complex microenvironment permissive to tumor development. Myeloid cells are crucial players in cancer-related inflammation. From transcriptional profiling of liver myeloid cells, we identified the gene encoding for the C-type lectin receptor CLEC4D as one of the genes upregulated during the inflammatory response that precedes cancer development in a spontaneous model of murine HCC. We hypothesized that CLEC4D may be involved in the molecular mechanisms that drive HCC pathogenesis. We used the murine model of diethylnitrosamine (DEN)-induced liver carcinogenesis and evaluated tumor growth in genetically modified mice lacking CLEC4D (CLEC4D KO mice), as compared to C57BL/6 wild type (WT) mice. We observed that tumor burden (number of tumors per mouse and tumor dimensions) was reduced in CLEC4D KO mice compared to WT mice. Gene expression analysis of tumor lesions showed that the tumor microenvironment of CLEC4D KO mice was less inflammatory. CLEC4D expression was then evaluated in surgical specimens and tissue microarrays from HCV+ HCC patients. CLEC4D-positive inflammatory cells (macrophages and granulocytes) were present both in the peritumor and in the tumor areas. The percentage of intratumor CLEC4D-positive cells inversely correlated with the degree of the lesion: CLEC4D expression was higher in dysplastic nodules compared to high grade HCCs. Our results indicate that the CLEC4D-dependent pathway contributes to the initiation and the progression of HCC. By targeting CLEC4D, we could modulate immune responses and provide an environment less favorable to tumor growth. An intervention at this level could represent a chemopreventive strategy to arrest the development of HCC in a cirrhotic liver.This work has been supported by Fondazione Cariplo, grant n° 2014-0962.

Citation Format: Elena Riboldi, Luca Di Tommaso, Nausicaa Clemente, Chiara Raggi, Elisa Forti, Simone Merlin, Fabio Pasqualini, Antonia Follenzi, Antonio Sica. Role of CLEC4D in inflammation-driven liver carcinogenesis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2677. doi:10.1158/1538-7445.AM2017-2677
Abstract 2678: Novel host-pathogen interactions of Helicobacter pylori and their implications to gastric cancer
Authors: Maiorov Emine Guven , Nussinov Ruth , Tsai Chung-Jung
Published: July 2017

About 20% of the cancer incidences worldwide have been estimated to be associated with infections. There is a strong correlation of some pathogens with various cancer types. Although presence of commensal microbiome helps chemotherapy to be more effective, pathogenic microbiota increases the cancer risk. Invading pathogens interact with the host mainly through proteins. To subvert host defense, pathogens hijack host pathways by mimicking the binding surfaces (interfaces) of host proteins. This similarity in interfaces permits the pathogenic protein to compete with host proteins to bind to a target protein, alter the physiological signaling and cause persistent infections as well as cancer. Detection of host-pathogen interactions (HPIs) and mapping the re-wired HPI network - along with its structural details - is critical for in-depth understanding of the underlying pathogenesis mechanisms of infections and pathogen-triggered cancers, and developing efficient therapeutics. Here, we developed a novel computational approach to identify novel HPIs by employing “interface mimicry”, We applied this approach to Helicobacter pylori, dominant species in gastric microbiome that greatly increases the gastric cancer risk in order to understand how they modulate host immunity and lead to tumorigenesis. We found that its proteins interfere with the functioning of host apoptosis pathway, cytokine and chemokine pathways, and also cell-cell adhesions. Our results shed light on the molecular mechanisms of resistance to apoptosis, immune evasion and loss of cell junctions that are seen in Helicobacter pylori-infected host cells. In conclusion, HPIs can help us unravel which human pathways are targeted by the pathogenic proteins and how they contribute to pathogenesis of infections and pathogen-triggered cancer. With a better grasp on immunomodulatory strategies of pathogens, we can develop better therapies against them.

Citation Format: Emine Guven Maiorov, Ruth Nussinov, Chung-Jung Tsai. Novel host-pathogen interactions of Helicobacter pylori and their implications to gastric cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2678. doi:10.1158/1538-7445.AM2017-2678
Abstract 2683: The gastrointestinal microbiome and its composition are critical for antitumor efficacy of immune checkpoint inhibition by anti-PD-L1
Authors: Cuiffo Benjamin G. , Parello Caitlin S. , Ritchie Chelsea , Pedrick Katie , Kury Alexandra , Costa Catarina , Dam Brett Van , Jung Jonathan , Lyng Gregory D. , Sonis Stephen T.
Published: July 2017

The intestinal microbiome has become increasingly appreciated as a significant mediator of systemic antitumor immunity/response in both naïve and treatment contexts. In naïve contexts, an intact intestinal microbiome has been demonstrated to enhance tumorigenesis, and its composition to mediate primary tumor growth kinetics. In the context of cancer treatment, antibiotic depletion of the intestinal microbiota has been reported to inhibit the efficacy of cyclophosphamide and that of the immune checkpoint inhibitor αCTLA4. Compositional modulation of the intestinal microbiota has been found to be sufficient to enhance the antitumor efficacy of αPD-L1. Here, we assessed the relative importance of the intestinal microbiota in mediating αPD-L1 antitumor efficacy in a B16.F10.SIY murine model of melanoma, by performing parallel efficacy studies in C57BL/6 germ-free (Taconic) or specific pathogen free (Taconic or Jackson) mice. We observed that αPD-L1 treatment provided significant antitumor efficacy of in Taconic mice carrying an intact microbiome; however, this efficacy was abolished in germ-free Taconic mice. Furthermore, we observed that tumors of Jackson mice carrying an intact but compositionally different microbiome did not respond to αPD-L1 treatment. Phenotyping of local tumor and systemic immune responses, as well as characterization of the intestinal microbiome in responder vs nonresponder animals provided mechanistic insights. Taken together, these observations suggest that rational modulation of the microbiome may enhance response to immune checkpoint inhibition, and indicate that the gastrointestinal microbiome and its composition are critical for the antitumor efficacy of αPD-L1.

Citation Format: Benjamin G. Cuiffo, Caitlin S. Parello, Chelsea Ritchie, Katie Pedrick, Alexandra Kury, Catarina Costa, Brett Van Dam, Jonathan Jung, Gregory D. Lyng, Stephen T. Sonis. The gastrointestinal microbiome and its composition are critical for antitumor efficacy of immune checkpoint inhibition by anti-PD-L1 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2683. doi:10.1158/1538-7445.AM2017-2683
Abstract 2684: Multiplex immunofluorescence profiling of tumor infiltrating immune subsets in HNSCC biopsies provides a powerful tool when combined with patient outcome data
Authors: Levin Matt , Lingen Mark , Schwartz David , Snyder Helen
Published: July 2017

Head and neck squamous cell carcinoma (HNSCC) is one of the growing number of tumors for which an anti-tumor immune response is implicated to play a role in the course of the disease. Profiling of the tumor microenvironment including specific infiltrating lymphocyte subsets, antigen presenting cells, expression of regulatory molecules on both tumor and immune cells and spatial relationships between cells could lead to predictive signatures for responsiveness to both conventional and immune modulatory therapies. While flow cytometry results in multi-parametric analysis of immune populations within the tumor, their context i.e. the spatial relationship of these cells to tumor and to other immune cells, is lost. In this current study we use Cell IDx’s novel UltraPlex technology, which is based on a simple two-step, autostainer compatible protocol using hapten labeled primary antibody cocktails followed by fluor labeled anti-hapten secondary cocktails to simultaneously detect 4 cellular markers on the same cell in tumor biopsies. Image registration of serial sections increases multiplexing to 12-16 markers. This technology, which allows generation of full immune subset profiling, quantitative marker expression and relative cellular localization, was applied to a HNSCC tumor microarray as a test system. Data are presented showing the potential of this technology for correlation of tumor “immune signature” with patient outcome.

Citation Format: Matt Levin, Mark Lingen, David Schwartz, Helen Snyder. Multiplex immunofluorescence profiling of tumor infiltrating immune subsets in HNSCC biopsies provides a powerful tool when combined with patient outcome data [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2684. doi:10.1158/1538-7445.AM2017-2684
Abstract 2692: Inflammatory patterns exhibited by African American colon tumor-derived cell lines
Authors: Sanchez Jenny E. Paredes , Ji Ping , Munoz-Sagastibelza Maria , Martello-Rooney Laura , Williams Jennie
Published: July 2017

Despite progress in closing the gap, health disparities still persist among African American (AA) colon cancer patients both in incidence and death rates. Previous studies from our group reported that colon tumors from AAs displayed hypermethylation of DNA regions in inflammatory genes such as NELL1, GDF1, ARHGEF4, and ITGA4 when compared to Caucasian Americans (CA). To assess potential differences in the inflammatory response, we utilized two AA colon cancer cell lines generated in our laboratory and compared them with the commercially available CAs colon cancer cell lines, Caco-2 and HT-29. Recent experiments by our group with the anti-inflammatory drugs Ibuprofen, Sulindac and Aspirin, showed significantly higher IC50 values in proliferation assays for AA cell lines compared to CA cell lines. Therefore, we evaluated the anti-inflammatory effects of these drugs by determining secretion of inflammatory cytokines and MAPKs activation in response to the pro-inflammatory cytokine TNF-alpha. The same parameters were tested for the anti-inflammatory cytokine IL-10. As hypothesized, our results in the CA cell lines demonstrated down-regulation of MAPKs activation in response to TNF-alpha after pre-treatment with Ibuprofen. On the contrary, Ibuprofen concentrations as high as the IC50 values for the CA cell lines were not able to induce down-regulation of MAPKs in the AA cell lines. Interestingly, IL-10 treatment was more effective in the AA compared to the CA cell lines, suggesting that the main anti-inflammatory cytokine of the colon will be more effective in controlling inflammation in AA colon tumors. Further studies are needed to elucidate the major differences in inflammatory responses between AA and CA colon cancer cell lines and their potential role in CRC health disparities. As it has been documented that AA colon cancer patients are less responsive to the chemotherapeutics Fluorouracil and Capecitabine, in future studies we will evaluate the effect of these therapeutic agents on AA and CA cell lines in terms of inflammation, cell viability, apoptosis and invasion.

Citation Format: Jenny E. Paredes Sanchez, Ping Ji, Maria Munoz-Sagastibelza, Laura Martello-Rooney, Jennie Williams. Inflammatory patterns exhibited by African American colon tumor-derived cell lines [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2692. doi:10.1158/1538-7445.AM2017-2692