bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 5307: Androgen Receptor promotes localization of E-cadherin to cell-cell junctions through Abi1 signaling
Authors: Porter Baylee , Nath Disharee , Krum Susan A. , Bratslavsky Gennady , Kuznetsov Vladimir A. , Kotula Leszek
Published: August 2019

According to American Cancer Society, prostate cancer is a slow progressing disease that affects nearly 50 percent of males over the age of 60. Every year, 165,000 new cases are diagnosed and 30,000 deaths are reported. Current therapies such as Androgen Depravation Therapy (ADT) and Anti-Androgen treatments such as Enzalutamide increase quality of life and extend survival but do not provide a definitive treatment and are ineffective in highly metastatic prostate cancer. Castrate Resistant Prostate Cancer (CRPC) is an untreatable highly metastatic form of prostate cancer and once diagnosed the survival rate is 1-2 years. Hence, the understanding of molecular mechanisms of CRPC is of critical importance. We previously linked prostate cancer to Abi1 gene. Abl interactor 1 (Abi1) is a scaffolding protein and an integral member of the WAVE Regulatory Complex (WRC). WRC is actin nucleation promoting factor that acts upstream of Arp2/3 to enhance the speed of actin polymerization and is critical for various cellular functions including cell-cell junction formation. Our previous research using a prostate cancer mouse models shows that loss of Abi1 expression leads to down-regulation of cellular adhesion proteins such as E-cadherin. Studies using our CRISPR KO RWPE cell line indicate that loss of Abi1 disrupts cell-cell junction formation via decreased levels of E-cadherin. Analysis of patient data demonstrated loss of Abi1 in a subset of CRPC patients. Castrate resistant tumor growth is androgen independent therefore anti-androgen therapy is ineffective. In search of a link between the androgen signaling and the role of Abi1 in prostate cancer we found that Abi1 gene contains androgen receptor (AR) binding sites. Consistent with the idea that Abi1 is an AR responsive gene, expression levels of Abi1 are increased following AR stimulation with the synthetic androgen, R1881, of the hormone sensitive cell line LNCaP. We also observed increased levels of E-cadherin at the cell-cell junctions. In contrast, cells lacking Abi1 do not form proper cell junctions neither respond to AR stimulation in the same way as wild type cells. We propose that Abi1 is a critical part of androgen signaling by promoting cell-cell junctions and tissue integrity. Supported by NCI R01 CA161018 (LK).

Citation Format: Baylee Porter, Disharee Nath, Susan A. Krum, Gennady Bratslavsky, Vladimir A. Kuznetsov, Leszek Kotula. Androgen Receptor promotes localization of E-cadherin to cell-cell junctions through Abi1 signaling [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 5307.
Abstract 5309: Inhibition of cancer stem-like cells in esophageal squamous cell carcinoma with SOCS-1 gene therapy
Authors: Yamamoto Ayumi , Munekage Eri , Serada Satoshi , Tsujii Shigehiro , Hiramatsu Kosuke , Fujimoto Minoru , Hanazaki Kazuhiro , Naka Tetsuji
Published: August 2019

INTRODUCTION: Cancer stem-like cells are thought to be one of the causes of cancer initiation and progression. They are associated with the resistance to radiotherapy and chemotherapy for various types of tumor including esophageal squamous cell carcinoma (ESCC). Therefore, cancer stem-like cells are promising therapeutic targets of cancer. Suppressor of cytokine signaling-1 (SOCS-1) was identified as a negative regulator of various cytokine signaling. We have previously demonstrated that overexpression of SOCS-1 showed a potent anti-tumor effect on ESCC through inhibiting of the JAK/STAT signaling pathway. This study aimed to evaluate the anti-tumor effect of SOCS-1 gene therapy using adenoviral vector (AdSOCS-1) against cancer stem-like cells in ESCC.

METHODS: ESCC cell lines were separated into aldehyde dehydrogenase (ALDH) positive and ALDH negative cells by ALDEFLOUR, and then sphere formation assays were performed. The inhibitory effects of AdSOCS-1 and AdLacZ on the sphere formation were evaluated using TE8, TE14 ESCC cell lines. The inhibition of sphere formation was also evaluated using ESCC cells obtained from ESCC PDX mice (ESCC8). Next, the expression of transcription factors associated with cancer stem-like cells in ESCC was evaluated by RT-PCR. The inhibitory effects on tumor formation by AdSOCS-1 were evaluated by tumorigenicity assay using TE8 xenograft mice.

RESULTS: In the sphere formation assay, ALDH positive TE8 cells and TE14 cells represented strong sphere formation capacity. Compared with AdLacZ infected ALDH positive cells, sphere formation of AdSOCS-1 infected ALDH positive cells was significantly inhibited. The inhibition of sphere formation was also confirmed in ESCC cells obtained from ESCC8 PDX mouse tumor tissue. Interestingly, the expression level of Sox2, a critical stem cell factor regulated by STAT3, was also decreased by AdSOCS-1. Furthermore, AdSOCS-1 decreased the tumorigenic activity of the ALDH positive ESCC tumor cells. CONCLUSIONS: A potent anti-tumor effect of SOCS-1 gene therapy on ESCC may be partially explained by inhibiting the expression of a STAT3 regulated transcription factor critical for cancer stem-like cells.

Citation Format: Ayumi Yamamoto, Eri Munekage, Satoshi Serada, Shigehiro Tsujii, Kosuke Hiramatsu, Minoru Fujimoto, Kazuhiro Hanazaki, Tetsuji Naka. Inhibition of cancer stem-like cells in esophageal squamous cell carcinoma with SOCS-1 gene 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 5309.
Abstract 5314: Smad4 loss upregulates chemokine expression and promotes tumor inflammation and growth in head and neck cancer
Authors: Masannat Jude , Wang Xuefeng , Cao Biwei , Song FeiFei , Chaudhary Ritu , Iglasia Janis de la , Gorgoglione Ciaara , Slebos Robbert , Chung Christine
Published: August 2019

Background: Head and neck squamous cell carcinoma (HNSCC) is the 6th most common cancer worldwide. Of the patients diagnosed with HNSCC, previous findings show that SMAD4 loss is more common in recurrent HNSCC patients compared with newly diagnosed cases and is strongly associated with poor patient survival and metastases. SMAD4 is a tumor suppressor gene and is a central mediator of the transforming growth factor β (TGF-β) signaling pathway and acts as a co-SMAD which binds receptor-regulated SMADs such as SMAD2 and 3. SMAD2/3/4 complex is important for regulating downstream gene transcription that is involved in tumor invasion and metastasis.

Purpose: Since the TGF-β pathway is highly dysregulated in HNSCC, we investigate in this study how SMAD4 downregulation alters TGF-β pathway signaling and the tumor microenvironment.

Results: Using isogenic HNSCC cell lines, we visualized using immunofluorescence staining that levels of activated phospho-SMAD2 in the nucleus are correlated with expression of SMAD4. Genome-wide screening using Gene Set Enrichment Analysis (GSEA) further revealed changes in gene expression during SMAD4 knockdown in HNSCC cells. From GSEA results, the 20 most significantly altered Gene Ontology (GO) pathways were determined. It was shown that majority of these GO pathways are associated with regulating neutrophil migration and chemotaxis with an upregulation of CXC chemokine gene expression, specifically with CXCL1. In contrast, anti-tumor chemokines, such as CXCL9 and CXCL11, were downregulated during loss of SMAD4 expression. Using an orthotopic mouse model we show that in vivo, decreased expression of SMAD4 promotes tumor take and growth.

Conclusion: Collectively, these results suggest that HNSCC tumors with SMAD4 loss may have poor prognosis attributed to immunosuppressive functions of chemokine expression that acts on tumor-associated neutrophils.

Citation Format: Jude Masannat, Xuefeng Wang, Biwei Cao, FeiFei Song, Ritu Chaudhary, Janis de la Iglasia, Ciaara Gorgoglione, Robbert Slebos, Christine Chung. Smad4 loss upregulates chemokine expression and promotes tumor inflammation and growth in head and neck 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 5314.
Abstract 536: NBTXR3 potentiate cancer-cell intrinsic interferon beta response to radiotherapy
Authors: Rodriguez-Ruiz Maria E , Pilones Karsten , Daviaud Camille , Kraynak Jeffrey , Darmon Audrey , Paris Sebastien , Demaria Sandra
Published: August 2019

NBTXR3 represent first in class functionalized radioenhancer optimized for efficient tumor binding and sustained local permanence after intratumoral injection. Recent results of phase III in locally advanced Soft Tissue Sarcoma patients established the significant clinical benefits of NBTXR3 activated by radiation therapy compared to radiotherapy alone. Moreover, preclinical studies using CT26 cells have demonstrated that NBTXR3 activated by RT can induce an anti-tumor immune-response and the abscopal effect. Radiotherapy (RT) can induce T cell-mediated anti-tumor immune responses by multiple mechanisms which include enhancing the recruitment of Batf3-dependent cross-priming dendritic cells (DCs). The latter is contingent on tumor-intrinsic IFN-I induction by cytosolic dsDNA via cGAS/STING pathway, a process that is regulated by the upregulation of Trex1 in a RT dose-dependent fashion (Nat Commun 2017; 8:15618). Here, we utilized the murine TSA breast cancer cell line to test the hypothesis that NBTXR3 strengthens the pro-immunogenic effect of local RT by potentiating tumor cells IFN-I response. For in vitro experiments, TSA cells were exposed to NBTXR3 (800uM) 16 hours prior to RT delivered by a 220-kV source (SARRP) at a dose rate of 283.2 cGy/min. Secreted IFNb in the supernatants was measured by ELISA. Pre-treatment with NBTXR3 enhanced TSA cell radiosensitivity as determined in clonogenic assays. Cell death, as measured by loss of plasma membrane integrity was accelerated by NBTX3 after irradiation of TSA cells with 6 and 8Gy after 24 hours of treatment. NBTXR3 enhanced the secretion of IFNb by irradiated cells. Data suggest that NBTXR3 may enhance the effectiveness of radiation and improve tumor immunogenicity, likely via the induction of IFN-I. The role of the cGAS/STING pathway in the effects of NBTX3 are under investigation in vitro and in vivo.

Citation Format: Maria E Rodriguez-Ruiz, Karsten Pilones, Camille Daviaud, Jeffrey Kraynak, Audrey Darmon, Sebastien Paris, Sandra Demaria. NBTXR3 potentiate cancer-cell intrinsic interferon beta response to radiotherapy [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 536.
Abstract 547: Recombinant immunotoxins targeting B-cell maturation antigen induce complete responses in bone marrow myeloma mouse model
Authors: Shancer Zoe , Liu Xiu-fen , King Emily , Bera Tapan , Pastan Ira
Published: August 2019

Background: Multiple myeloma (MM) is a B-cell malignancy for which new treatments are urgently needed. B-cell maturation antigen (BCMA) is a lineage-restricted differentiation protein highly expressed on MM and an ideal target for immunotherapy of MM. Recombinant immunotoxins (RITs) are chimeric proteins composed of the Fv or Fab portion of an antibody fused to a fragment of Pseudomonas Exotoxin A (PE). One of these, Lumoxiti, is FDA approved for the treatment of drug-resistant hairy cell leukemia, another B-cell malignancy. LMB-75 is an immunotoxin with an anti-BCMA dsFv of mAb BM306 fused to domain III of PE, and LMB-70 is an anti-BCMA Fab fused to domain III of PE. We previously treated H929 myeloma cells grown as subcutaneous tumors with anti-BCMA immunotoxins that are very effective in killing cultured cells and cells from patients. We observed tumor growth inhibition but not complete tumor responses. Goal: Here we used H929 cells to develop a bone marrow mouse model that is more relevant to human disease and to determine if these immunotoxins are more active against H929 cells growing in bone marrow.

Methods: The NCI-H929 cell line was transfected with luciferase and GFP, recycled through the bone marrow of a mouse and enriched by flow to isolate cells with high GFP expression, which were used to inoculate tumors IV into NSG mice. Mice were treated IV with immunotoxins and tumor burden was assessed using bioluminescence imaging.

Results: H929-luc-GFP cells grow uniformly in the bone marrow of mice, cause hind limb paralysis around day 40, and provide a relevant in vivo model for testing RITs. We achieved complete responses when treating mice with 1.5 mg/kg LMB-75 or LMB-70 given QODX5 beginning on days 4 or day 8. Mice in all treatment groups were disease free at 3 months. An immunotoxin targeting CD22, which is not expressed on H929 cells, or an anti-BCMA immunotoxin with a mutation that inactivates toxin activity did not have any anti-tumor activity.

Conclusions: LMB-75 and LMB-70 induce complete, durable remissions of H929-luc-GFP cells growing in mouse bone marrow without toxicity to mice. These promising results support further pre-clinical development of these agents for MM.

Citation Format: Zoe Shancer, Xiu-fen Liu, Emily King, Tapan Bera, Ira Pastan. Recombinant immunotoxins targeting B-cell maturation antigen induce complete responses in bone marrow myeloma mouse model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 547.
Abstract 614: Cytomegalovirus (CMV) reactivation and patient survival in head and neck cancer
Authors: Nelson Heather H. , Miller Jeffrey S. , Hunter-Schlichting DeVon , Butler Rondi A. , Kelsey Karl T.
Published: August 2019

There is building evidence that cytomegalovirus (CMV) may contribute to the development of solid tumors, however to date this has not been investigated in head and neck cancer (HNC). CMV is a highly prevalent, latent herpesvirus infecting over 50% of the population. CMV maintains latency in CD34+ cells, and recent work has demonstrated these latently infected cells preferentially differentiate into immunosuppressive monocytes. However, CMV is not solely immune suppressive as highly cytotoxic adaptive natural killer (NK) cells arise specifically in response to CMV reactivation. Here, we have investigated whether biomarkers of CMV reactivation are associated with patient survival in non-smoking HNC (n=184). CMV DNAemia was assessed using digital PCR, and a threshold of 1000 copies/mL serum was defined as reactivation; 22% of patients met this definition of CMV reactivation, however they did not have significantly worse survival than those without CMV reactivation (HR 1.5 (95% CI 0.7 - 3.0)). Monocytes that mobilize to the cancer site contribute to tumor-associated inflammation. Therefore, we explored whether a biomarker of inflammation, CRP, modified the association of CMV reactivation and HNC patient survival. In the absence of inflammation, there was no association between CMV reactivation and patient survival (HR 0.90 (95% CI 0.30 - 2.71)). However, those with both CMV reactivation and high inflammation had dramatically worse survival (HR 8.86 (95% CI 3.63 - 21.64)). These data are consistent with the recent report that CMV infected monocytes are immunosuppressive and suggest that stimulation of these monocytes to the tumor site may negatively impact patient survival. Future work should address the generalizability of this finding to other cancer types and determine whether CMV infected myeloid cells are present in the tumor microenvironment.

Citation Format: Heather H. Nelson, Jeffrey S. Miller, DeVon Hunter-Schlichting, Rondi A. Butler, Karl T. Kelsey. Cytomegalovirus (CMV) reactivation and patient survival in head and neck 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 614.
Abstract 625: Association between obesity and prostate cancer disease risk and mortality among African American men
Authors: Pichardo Margaret Saira , Minas Tsion , Tang Wei , Dorsey Tiffany H. , Ambs Stefan
Published: August 2019

Prostate cancer (PCa) is a major cause of cancer death in U.S. men. Age-adjusted mortality rates for men of African ancestry (40.8 per 100,000) are more than twice that of men of European ancestry (18.2 per 100,000). Men of African ancestry are more likely to have advanced stage cancer at diagnosis and lower prostate cancer survival rates relative to men of European ancestry of similar age and stage at diagnosis. Risk factors that may explain this survival disparity remain poorly understood. Obesity, a major risk factor for cancer development, aggressiveness and progression, disproportionately affects US men of African ancestry. Age-adjusted prevalence of obesity are higher among men of African ancestry (38.0%) compared to men of European ancestry (34.7%). While it has been previously suggested that obesity may worsen disease-related outcomes among prostate cancer patients, the relationship of obesity and prostate cancer mortality remains unclear, with studies showing mixed or null results in men of African ancestry. Less is known about the underlying biological mechanisms that may contribute to the racial differences observed in the link between obesity and prostate cancer. We previously reported an obesity paradox among African-American men in the NCI-Maryland Prostate Cancer-Case Control Study, with overweight and obese men having a lower risk of being diagnosed with the disease. Here, using Cox proportional hazard regression modeling, we estimated the risk of a PCa mortality for the 976 cases in the study. Our primary analysis suggests an obesity paradox, where obesity may protect against disease mortality among the African-American men. In subsequent analyses, we will examine the role of immune and inflammation markers in mediating or moderating the observed relationship of obesity with PCa in these men.

Citation Format: Margaret Saira Pichardo, Tsion Minas, Wei Tang, Tiffany H. Dorsey, Stefan Ambs. Association between obesity and prostate cancer disease risk and mortality among African American men [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 625.
Abstract 637: A prospective study of tea and coffee intake and risk of glioma
Authors: Cote David J. , Bever Alaina M. , Wilson Kathryn M. , Smith Timothy R. , Smith-Warner Stephanie A. , Stampfer Meir
Published: August 2019

Background: Tea and coffee have anti-inflammatory, anti-oxidant and neuroprotective effects mediated by a variety of compounds, including polyphenols. Observational studies suggest that tea and coffee intake may reduce risk of certain cancers, although the data on glioma risk are limited and inconclusive.

Methods: We evaluated the association between tea, coffee, and caffeine intake and risk of glioma in the female Nurses’ Health Study (NHS, n=92,389, followed 33 years) and Nurses’ Health Study II (NHSII, n=95,242, followed 23 years) and the male Health Professionals Follow-up Study (HPFS, n=49,885, followed 29 years). Cumulatively updated tea and coffee intake were derived from validated quadrennial food frequency questionnaires. Glioma cases were confirmed by medical record review. Age-adjusted hazard ratios of glioma by category of beverage intake were estimated using Cox proportional hazards models. Associations across the combined cohorts were calculated using fixed effect meta-analysis.

Results: We documented 554 incident cases of glioma, including 256 in NHS, 87 in NHSII, and 211 in HPFS (159, 52, 151 glioblastomas, respectively). Compared to <1 cup/week, higher tea consumption was inversely associated with glioma risk in women (HR=0.65, 95% CI 0.41-1.03 for >2 cups/day, p-trend=0.03), and was inversely, but not significantly, associated in men (HR=0.70, 95%CI 0.30-1.61 for >2 cups/day, p-trend=0.30). In women and men combined, the corresponding HR was 0.66 (95% CI 0.44-0.99) for >2 cups/day (p-trend=0.02). We observed no significant associations between caffeinated, decaffeinated, or total coffee intake and glioma risk in men or women. We found no material differences in the results when baseline values were used, when responses were lagged by eight years, or when cases were limited to glioblastoma only.

Conclusion: In three large, prospective cohort studies of men and women, tea intake was inversely associated with glioma risk, particularly in women. No significant associations were observed for coffee intake of any type and glioma risk. These results merit further exploration in other prospective studies.

Note: This abstract was not presented at the meeting.

Citation Format: David J. Cote, Alaina M. Bever, Kathryn M. Wilson, Timothy R. Smith, Stephanie A. Smith-Warner, Meir Stampfer. A prospective study of tea and coffee intake and risk of glioma [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 637.
Abstract 671: Evaluation of machine learning tools for cancer drug response prediction with genomic profile data and drug response data from PDX model studies
Authors: Gu Henry , Jiang Jingjing
Published: August 2019

Cancer are diseases caused by genomic aberrations which lead to abnormal cell proliferation and metastasis. Cancer treatment based on cancer mutation profiles are the focus of research and development of cancer precision medicine. Currently only a small percentage of cancer patients’ genomic information are associated with known drug responses, while others lack known cancer drivers or have cancer drivers that are not druggable. Machine learning (ML) tools have been developed recently for cancer biomarker discovery and cancer drug response prediction. However, due to a lack of sufficient amount of high quality drug response data, especially data for new drugs, the application of ML tools in this area is still in its early stage. In this study, we compared the performance of about a dozen ML methods, such as random forest classifiers, logistic regression classifiers, and support vector machines (SVM), trained on data of about 2300 treatment responses to average 12 different cancer drugs in 98 NSCLC, 55 gastric and 38 HCC PDX models with WES, CNV and RNA-seq information. Data preparation including genomic profile data selection, dimensionality feature reduction and processing was performed with considerations of known cancer gene functions, signal pathways, and pharmacodynamics information. Each dataset was randomly divided into training dataset and test dataset for ML algorithm training and evaluation. Performance of ML algorithms in testing was measured by their drug response prediction accuracy. Different regularization methods, such as LASSO and Elastic Net, were also evaluated in order to improve classification accuracy and identify relevant biomarker features. From comparing results from different algorithms or from the same algorithms but with differently prepared datasets, it seems that selection of functionally unknown gene aberrations for data preparation plays a significant role in prediction accuracy. Increasing dataset number or different data selection in different cancer types can improve prediction accuracy.

Citation Format: Henry Gu, Jingjing Jiang. Evaluation of machine learning tools for cancer drug response prediction with genomic profile data and drug response data from PDX model studies [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 671.
Abstract 69: Integrin α6β4 associates with plectin and vimentin in focal adhesions to enhance breast cancer cell invasion
Authors: Qi Lei , Knifley Teresa , Chen Min , O’Connor Kathleen L.
Published: August 2019

Integrin α6β4 binds plectin to associate with intermediate filaments such as vimentin. While vimentin and integrin α6β4 are associated with the aggressiveness of triple negative breast cancer (TNBC), the biological importance of their association is not clear. Here, we utilized naturally occurring Epidermolysis Bullosa mutations in the integrin β4 subunit that are deficient in plectin binding to investigate the association between integrin α6β4 and vimentin. Using integrin β4-deficient BT549 cells, we generated cell lines that expressed integrin β4 wild type (β4-wt), plectin binding mutants (β4-R1225H or β4-R1281W), 1355-1662 deletion mutant (β4-Δ1355-1662; which retains plectin binding but deletes the signaling domain) or an empty control vector (EV). Migration assay and three-dimensional (3D) culture were performed to test whether integrin α6β4 signaling and its association with plectin contribute to the migratory and invasive phenotypes. Compared to EV cells, β4-wt increases cell migration and 3D invasive growth, but the β4-R1225H and β4-R1281W could not. CRISPR knockout of plectin also blocked β4-wt 3D cell growth. Utilizing total internal reflection fluorescence (TIRF) microscopy, we found that integrin β4-wt and β4-Δ1355-1662 were recruited to focal adhesions (FAs, indicated by paxillin co-staining) on laminin-1 plus fibronectin matrices, but not when plated on laminin-1 or fibronectin alone. Integrin β4-R1225H and β4-R1281W did not localize to FAs. Similarly, integrin β4-wt in plectin knockout cells could not aggregate in FAs. Furthermore, we observed that integrin αv and β1 colocalized with integrin β4 in FAs. Proximity ligation assay (PLA) indicated that the close interaction of integrin β1 and plectin. Interestingly, depletion of integrin β1 significantly reduced integrin β4 accumulation in FAs. Further immunostaining showed that integrin β4, plectin, and vimentin aggregated in FAs in the central area of the cell where FAs predominantly formed. Depletion of vimentin did not impact the recruitment of integrin β4 in FAs or cell proliferation, but significantly suppressed cell migration and 3D growth in β4-wt cells. Integrin β4-plectin-vimentin complexes were also found in MDA-MB-231 cells where they co-localized with paxillin and connected with stress fibers. In summary, our study demonstrates the essential roles of plectin binding and vimentin in promoting the migratory and invasive phenotypes by integrin α6β4 signaling in TNBC. Our study further highlights a novel function of plectin binding and integrin β1 in enhancing integrin β4 dynamics.

Citation Format: Lei Qi, Teresa Knifley, Min Chen, Kathleen L. O’Connor. Integrin α6β4 associates with plectin and vimentin in focal adhesions to enhance breast cancer cell invasion [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 69.
Abstract 692: Treating spinal cord metastases with tumor treating fields
Authors: Yesharim Ofir , Naveh Ariel , Bomzon Ze'ev
Published: August 2019

Introduction: Tumor Treating Fields (TTFields) is an anti-mitotic technology utilizing low-intensity (1-3 V/cm) electric fields within the medium frequency range (100-300 kHz) to treat solid tumors. TTFields are currently approved for the treatment of Glioblastoma (GBM). Some cancer types, such as breast cancer, lung cancer, and melanoma, frequently result in metastases to the spinal cord. Transducer array positioning used to treat abdominopelvic diseases (e.g. pancreatic cancer), in which one pair of arrays are placed on the anterior and posterior of the patient, and another pair of arrays placed on the lateral aspects of the patient have been shown to be inefficient for treating the spinal cord because the clinical threshold for field intensity of 1V/cm is not reached in the spine when these layouts. The structure of the spine, in which a relatively resistive bone structure encapsulates a highly conductive layer of fluid (cerebrospinal fluid), shunts the current delivered across the body by the arrays away from the spine, reducing the field within the spine to below the therapeutic threshold. To overcome this limitation, a new approach of array placement on the body is needed. Here we present a simulation-based study designed to identify array layouts that effectively deliver TTFields to the spine.

Methods: To simulate delivery of TTFields to the spine, we used a human male 34 years old realistic computerized model (DUKE v3.1 by ITI’S, Zurich). In order to generate TTFields, an alternating current with current density of 200mA/disk with a frequency of 150 kHz was imposed on the outer surfaces of the disks of each pair of arrays. The simulations were performed using ZMT's Sim4Life v4.0 electro-quasi-static solver.

Results: One of the array layouts tested was placement of a pair of arrays on the back of the patient. One array is placed above the target region in the spine to which treatment would be delivered, and the other array is placed below the region. With this configuration, a high electric field is induced within the spinal cord and surrounding CSF. Mean field intensity within the spine and nerves in between vertebrae T8-T9 at the top, and L3-L4 at the bottom were calculated at a value of 1.77 V/cm. It is important to note that the electric field is oriented along the spine in this instance (a vertical field). In general, the whole spine could be treated by placing one array on the neck, and one at the bottom of the spine.

Conclusions: Placing two transducer arrays on the patient’s back allows single-direction treatment of the spinal cord and nerves. Further work should be conducted to find an effective treatment in the perpendicular direction.

Citation Format: Ofir Yesharim, Ariel Naveh, Ze'ev Bomzon. Treating spinal cord metastases with tumor treating fields [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 692.
Abstract 695: Using PSA dynamics to predict patient-specific responses to intermittent androgen deprivation
Authors: Brady Renee , Enderling Heiko
Published: August 2019

Intermittent androgen deprivation therapy (IADT) is an attractive treatment approach for biochemically recurrent prostate cancer, whereby cycling treatment on and off has been shown to limit toxicities and reduce cumulative dose. While IADT has been shown to delay the development of treatment resistance, underlying mechanisms and actionable biomarkers are required to accurately predict when resistance will emerge and how to maximally delay time to progression. We developed a quantitative framework to simulate the enrichment of prostate cancer stem cell dynamics during treatment as a plausible mechanism of resistance evolution. Using simulated dynamics of cancer stem cells and non-stem cancer cells we derive longitudinal blood serum prostate-specific antigen (PSA) concentrations that were calibrated to and validated with data of 86 patients undergoing multiple cycles of IADT. Model analysis suggests that cancer stem cell proliferation patterns correlate with PSA dynamics and patient outcomes. Learning these dynamics adaptively from the earlier treatment cycles in individual patients can predict the evolution of resistance in subsequent IADT cycles with a predictive power of 80%, which warrants prospective evaluation in a clinical setting.

Citation Format: Renee Brady, Heiko Enderling. Using PSA dynamics to predict patient-specific responses to intermittent androgen deprivation [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 695.
Abstract 71: NEDD8-activating enzyme inhibitor MLN4924 reduces cell viability and induces apoptosis in chemoresistant cancer stem-like cells of human urothelial carcinomas in vitro and in vivo
Authors: Liao Shih-Ming , Hsu Fu-Shun , Yang Shao-Ping , Chang Yu-Wei , Chow Po-Ming , Pu Yeong-Shiau , Tsai Yu-Chieh , Kuo Kuan-Lin , Huang Kuo-How
Published: August 2019

Emerging evidence indicates that cancer stem cells (CSCs) may play a crucial role in cancer tumorigenesis, metastasis, and drug resistance. To develop treatment to inhibit CSCs provides promising target for cancer therapy. In this study, we identified a subpopulation of chemoresistant cancer stem-like cells of UCs (T24/R) after chemotherapeutic drug selection from T24, a bladder UC cell line. The T24/R cells displayed stemness markers (SOX2, Nanog, and Kruppel-like factor 4), high tumorigenicity in vivo, and enhanced invasion ability because of their epithelial-mesenchymal transition (EMT) properties. A neddylation inhibitor, MLN4924, efficiently inhibited viability and migration as well as induced apoptosis in the T24/R cells with concomitant suppression of stemness and EMT markers. Our findings suggest that MLN4924 effeiciently suppressed chemoresistant cancer stem-like UC cells and was a promising agent to conquer drug resistance in human bladder UCs.

Citation Format: Shih-Ming Liao, Fu-Shun Hsu, Shao-Ping Yang, Yu-Wei Chang, Po-Ming Chow, Yeong-Shiau Pu, Yu-Chieh Tsai, Kuan-Lin Kuo, Kuo-How Huang. NEDD8-activating enzyme inhibitor MLN4924 reduces cell viability and induces apoptosis in chemoresistant cancer stem-like cells of human urothelial carcinomas 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 71.
Abstract 712: Down-regulation and nuclear localization of survivin by sodium butyrate induces caspase-dependent apoptosis in human oral mucoepidermoid carcinoma
Authors: Ahn Chi Hyun , Cho Sung-Dae
Published: August 2019

Sodium butyrate (NaBu) is a histone deacetylase inhibitor that possess an apoptotic ability. However, the molecular mechanism by which NaBu induces apoptosis in human oral mucoepidermoid carcinoma (MEC), a type of salivary gland tumor, remains unclear. The anticancer effects of NaBu and its related molecular mechanisms were determined by trypan blue exclusion assay, 4'-6-diamidino-2-phenylindole staining, live/dead assay, human apoptosis array, RT-PCR, western blotting, immunocytochemistry, preparation of nuclear fractions, and nude mice tumor xenograft. In this study, we found that NaBu inhibited growth and induced apoptosis in the human oral MEC cell lines MC3 and YD15 with the acetylation of histone proteins H2A and H3. NaBu apparently down-regulated survivin protein, as evidenced by the results of the human apoptosis antibody array, and modulated it at the post-translational process. Interestingly, NaBu caused nuclear translocation of survivin protein in both cell lines. NaBu also resulted in decreased expression levels of Bcl-xL mRNA and protein, leading to induction of caspase-dependent apoptosis in human oral MEC cell lines. In addition, NaBu administration inhibited tumor growth in vivo at a dosage of 500 mg/kg/day, but it did not cause any hepatic or renal toxicity. This study provides new insights into the molecular mechanism of apoptotic actions by NaBu in human oral MEC and the basis of its clinical application for the treatment of human oral MEC.

Citation Format: Chi Hyun Ahn, Sung-Dae Cho. Down-regulation and nuclear localization of survivin by sodium butyrate induces caspase-dependent apoptosis in human oral mucoepidermoid carcinoma [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 712.
Abstract 717: Erianin induces autophagy-dependent apoptosis in oral cancer cells
Authors: Lin Chiao-Wen , Yang Shun-Fa
Published: August 2019

Oral squamous cell carcinoma (OSCC) is a leading cause of cancer-related deaths worldwide. It has a very poor prognosis with 5-year over survival rate of only 50%. Thus, it is important to identify effective therapeutic interventions against oral cancer. The present study was designed to evaluate the effect of erianin, a natural bibenzyl compound found in a traditional Chinese orchid Dendrobium chrysotoxum, on human oral cancer cell proliferation. Results of the study revealed that treatment with erianin significantly reduced the viability of different OSCC cell lines. Erianin exerted its cytotoxic effect by inducing cell cycle arrest at G2/M phase and caspase-dependent apoptotic pathways. Both intrinsic and extrinsic pathways were found to be involved in erianin-mediated cell death. In addition, treatment with erianin also increased autophagy in OSCC cells. With further analysis, it was found that erianin induced both apoptosis and autophagy by regulating MAPK signaling pathways. Taken together, our study indicates that erianin plays an important role in reducing oral cancer cell viability, and thus, can be considered as a potential anticancer agent.

Citation Format: Chiao-Wen Lin, Shun-Fa Yang. Erianin induces autophagy-dependent apoptosis in oral cancer 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 717.
Abstract 722: Epigenetic regulation of the Birc5 promoter explains mechanism of action of YM-155 in synovial sarcoma
Authors: Mika Aleksander , Luelling Sarah , Pavek Adriene , Parkinson Neil , Heyneman Alexandra , Barrott Jared J.
Published: August 2019

YM-155 is an anti-cancer therapy that has advanced into 11 different human clinical trials to treat various cancers. This apoptosis-inducing therapy indirectly affects the protein levels of Survivin (Gene: Birc5), but the molecular underpinnings of the mechanism remain largely unknown. Synovial sarcoma is another cancer with high protein expression of Survivin. We investigated whether YM-155 would be a viable therapeutic option to treat synovial sarcoma. We, therefore, applied YM-155 therapy to human synovial sarcoma cell lines and a genetically engineered mouse model of synovial sarcoma. We discovered that YM-155 exhibited nanomolar potency against human synovial sarcoma cell lines and the treated mice with synovial sarcoma demonstrated a 50% reduction in tumor volume compared to control treated mice. We further investigated the mechanism of action of YM-155 by looking at the change of modifications of the histone tails that were near the Birc5 promoter. Using chomatin immunoprecipitation (ChIP) we discovered that the histone epigenetic marks of H3K27 for the Birc5 promoter changed upon YM-155 treatment. H3K27me3 increased whereas the H3K27ac decreased, highlighting the decrease of the protein Survivin occurs through epigenetic silencing of the gene’s promoter. The treatment of YM-155 was accompanied by an increase in NFkB protein expression, which indicates an attempt of the cell to initiate a positive feedback due to the decrease in Survivin expression. This combination of molecular events eventually resulted in Caspace 3/7/8 upregulation and death of the sarcoma cells.

Citation Format: Aleksander Mika, Sarah Luelling, Adriene Pavek, Neil Parkinson, Alexandra Heyneman, Jared J. Barrott. Epigenetic regulation of the Birc5 promoter explains mechanism of action of YM-155 in synovial sarcoma [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 722.
Abstract 725: Anticancer effect and mechanism of exosomes mediated microRNA let-7b in breast cancer cells
Authors: Biantiao Xu
Published: August 2019

Exosome is referred as membrane-bound nano-vesicles secreted by various mammalian cells. It can be found in different body fluids, such as plasma, saliva, urine, latex, cerebrospinal fluid, ascites, and cell supernatant, which contains a large number of proteins, miRNAs, mRNAs, lipids, nucleic acids, peptides and other substances. Exosome plays a pivotal role in the information transmission signals between cells and the diagnosis and prognosis of diseases as well as drug evaluation. It has become an emerging field in cancer research recently. Therefore, we separated exosomes from human kidney embryo cell (HEK-293) by ultra high speed centrifugation. To identify exosomes from their surface specific proteins by Western blotting analysis. We found enrichment of exosome markers CD63 and TSG101 without Calnexin protein in the exosoms so confirmed that exosome was successfully isolated. Then, we transfered mRNA let-7b into the exosomes by electric transfection further evaluated the effects of cytotoxicity and apoptosis induction on human breast cancer MCF-7 cells by CCK 8 assay Hochest 33342-PI and AnnexinV-PI dual staining analysis, respectively. The results showed that exosome mediated microRNA let-7b exhibited significant anticancer activity and apoptosis induction in a concentration-dependent manner in MCF-7 cells. Moreover, exosome mediated let-7b significantly up-regulated the expression levels of apoptosis related proteins casepase 3, casepase 9, and PARP determined by Western blotting analysis. Our results indicate that the exosomes mediated microRNA such as let-7b can effectively inhibit cell growth and induce apoptosis against breast cancer cells and it may be developed as a novel anticancer agent in the treatment of cancer clinically.

Citation Format: Xu Biantiao. Anticancer effect and mechanism of exosomes mediated microRNA let-7b in breast cancer 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 725.
Abstract 737: NF-κB pathway activation by clonal mutations contributes to the recurrence of nasopharyngeal carcinoma
Authors: You Rui , Liu You-Ping , Chen Ming-Yuan
Published: August 2019

Objectives: Identification and characterization of the genomic features that potentially drive NPC recurrence.

Methods: We performed whole-genome/whole-exome sequencing of fresh tumors and corresponding blood samples from 55 rNPC and 44 pNPC patients. Additionally, previously published pNPC exome data were integrated for analysis. Immunohistochemistry and histologic analyses were performed to identify novel biomarkers among the differential mutational events between pNPC and rNPC in independent cohorts of 148 rNPC and 237 pNPC samples with complete clinical follow-up.

Results: rNPC and pNPC tissues had similar mutational burdens; however, the number of clonal mutations was increased in rNPC samples. TP53 and three NF-κB pathway components (TRAF3, CYLD and NFKBIA) were significantly mutated in both pNPC and rNPC. Notably, mutations in TRAF3, CYLD and NFKBIA were all clonal in rNPC; however, 55.6-57.9% of them were clonal in pNPC (P < 0.05). In general, the number of clonal mutations in NF-κB pathway-associated genes was significantly higher in rNPC than in pNPC (P < 0.05). Moreover, the nuclear abundance of NF-κB protein was significantly greater in pNPC samples with local regional relapse than in those without relapse (P = 0.006). Further, in both the pNPC training and validation cohorts, high nuclear NF-κB levels were an independent negative prognostic marker for locoregional relapse-free survival (LRRFS) in pNPC. Accordingly, concurrent chemotherapy for patients with high nuclear NF-κB reduced the rate of locoregional relapse. Lastly, we functionally validated that inhibition of NF-κB enhanced both radiosensitivity and chemosensitivity in NPC cells, strongly supporting our in vivo results.

Conclusion: NF-κB pathway activation by clonal mutations plays an important role in promoting the recurrence of NPC. Moreover, nuclear accumulation of NF-κB is a prominent biomarker for predicting LRRFS and suggesting treatment for pNPC patients. Finally, blocking NF-κB activity may be a novel and effective therapeutic modality for treating NPC.

Citation Format: Rui You, You-Ping Liu, Ming-Yuan Chen. NF-κB pathway activation by clonal mutations contributes to the recurrence of nasopharyngeal carcinoma [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 737.
Abstract 74: Heterogeneity response to afatinib in gastric cancer patient with uncommon EGFR mutations
Authors: Liu Qin , Wei Jia , Yang Yang , Wang Yue , Liu Baorui , Shao Yang
Published: August 2019

Introduction: Gastric cancer is the third leading cause of cancer mortality worldwide. Gatric cancer based on driver gene mutation detection may benefit patients by facilitating molecular targeted drugs development and improving survival in gastric cancer patients. On the other hand, the complex and heterogeneous molecular mechanisms of gastric cancer also plays an essential role in the drug resistance.

Methods: Whole exome sequencing (WES) was performed, revealing uncommon EGFR ex21 L861Q and ex18 G719S mutation of formalin-fixed paraffin-embedded sections from primary tumor and different metastatic lesions in a gastric cancer patient. The periodic circulating tumor DNA (ctDNA) was also determined by next generation sequencing (NGS). Stable gastric cancer cell and NIH-3T3 cell lines harboring the mutations were established to investigate the effect and mechanisms.

Results: Tumors with compond EGFR L861Q/G719S mutations and EGFR gene amplfication are sensitive to afatinib, which caused tumor progression in short time. However, the lung metastatic lesion, which lacked EGFR gene amplification demonstrated primary resistance to afatinib. A dramatic increase of MET gene copy number may collectively related to the patient’s rapid progression. Periodic mutation profiling of patient’s ctDNA by NGS correspondingly revealed compond EGFR L861Q/G719S mutations, and a consitent increase of MET gene amplification. In in vitro studies, afatinib treatment reduced proliferation and inhibited EGFR phosphorylation in L861Q/G719S and L861Q mutant cells.

Conclusions: Afatinib may be a beneficial therapeutic option for a subset of gastric cancer patients with rare EGFR mutations in their tumors. Our results also illustrated the great potential of ctDNA profiling for treatment decision-making to patients with gastric cancer.

Note: This abstract was not presented at the meeting.

Citation Format: Qin Liu, Jia Wei, Yang Yang, Yue Wang, Baorui Liu, Yang Shao. Heterogeneity response to afatinib in gastric cancer patient with uncommon EGFR 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 74.