bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 4520: Lymphatic vessels regulate exosome trafficking from tumors
Authors: Maillat Lea , Potin Lambert , Kilarski Witold W. , Swartz Melody A. 
Published: August 2019

Abstract
Prior to metastasis, tumor-draining lymph nodes and distant organs are altered by a number of tumor-derived factors that help to both suppress host immunity as well as form an environment that supports metastatic tumor cells, i.e., a pre-metastatic niche. Recent studies suggest that pre-metastatic niches are induced by vesicles, including exosomes, secreted by tumor cells and cells of the tumor microenvironment. Here, we investigated the contribution of lymphatic vessels, particularly the lymphatic endothelial cells (LECs), in the active regulation of tumor exosome production and trafficking. To track exosomes, we purified and fluorescently labeled exosomes from in vitro cultures of the mouse melanoma cell line B16 F10 and of the human melanoma cell line Me260LN. Upon injection into the mouse ear dermis, fluorescent exosomes were observed within minutes in draining lymphatics, but not in surrounding blood vessels. Using the B16 F10 melanoma model overexpressing the lymphangiogenic growth factor VEGF-C, we found that upon intratumoral injection of exosomes, LECs within the tumor microenvironment abundantly take up exosomes, and at higher levels than blood endothelial cells, delivering exosomes to draining lymph nodes and eventually to the blood. In transgenic mice lacking dermal lymphatics, exosomes injected intratumorally were absent in the lymph nodes and present in far lower amounts in the blood compared to those injected into wild type mice. Additionally, while the density of endogenous blood exosomes increased upon tumor growth in wild type mice, no significant change in blood exosome density was observed in transgenic mice. Using an in vitro model where LECs are seeded onto porous inserts, we found that LEC transport of tumor exosomes occurs preferentially from their basal to apical side, and that some of these exosomes were taken up and stored intracellularly. Together, these findings suggest that lymphatic vessels constitute a major route of tumor exosome distribution to the systemic circulation and that LECs actively regulate exosome transport by active uptake.
Citation Format: Lea Maillat, Lambert Potin, Witold W. Kilarski, Melody A. Swartz. Lymphatic vessels regulate exosome trafficking from tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4520.
Abstract 4541: Malignant and non-malignant cells from primary tumor and lymph node metastasis ecosystems show different behavior for patient-associated protein signatures in head and neck cancer
Authors: Busso-Lopes Ariane F. , Rivera César , Mello Barbara P. , Villa Luisa L. , González-Arriagada Wilfredo , Leme Adriana F. Paes 
Published: August 2019

Abstract
Although lymph node metastasis is the main prognostic factor in patients with head and neck squamous cell carcinoma (HNSCC), the molecular signals involved in this process are poorly characterized and no molecular markers are currently used in clinical practice. Recently, cancer is being viewed as an ecosystem, in which tumor cells cooperate with each other and host cells in their microenvironment. Herein, we mapped the proteome of primary tumor and matched lymph node ecosystems, isolating malignant and non-malignant cells, to better understand the mechanisms underlying lymph node metastasis. For that, we used formalin-fixed paraffin-embedded (FFPE) primary tumors and paired lymph nodes from 27 HNSCC patients positive (N+, n=13) and negative (N0, n=14) for lymph node metastasis using laser microdissection combined with mass spectrometry-based proteomics. An average of 2,266 ± 216 proteins was identified in primary tumor and lymph node ecosystems. A hundred and five differentially abundant proteins from malignant cells in the primary site (N+ vs N0) were mainly involved in RNA stability and metabolism, while inflammation and splicing processes, respectively, were overrepresented in N+ vs N0 non-malignant cells signatures from primary tumor (N=33) and lymph node (N=13) sites (Student's t-test; P-value≤0.05), indicating particular lymph node metastasis signatures for each cell population. Interestingly, the protein pattern of malignant cells from the primary site and matched lymph nodes showed an individual patient-specific metastasis profile through hierarchical clustering analysis; however, the profile of non-malignant cells does not represent patient-specific subpopulations and grouped according to the site of isolation (primary tumor and lymph node microenvironment). Our data reveal potential protein signatures associated with prognosis in HNSCC, as well as a non-specificity of protein patterns from host non-malignant cells that can be related with the immunosurveillance failure. Financial support: FAPESP (Process number 2015/19191-6).
Note: This abstract was not presented at the meeting.
Citation Format: Ariane F. Busso-Lopes, César Rivera, Barbara P. Mello, Luisa L. Villa, Wilfredo González-Arriagada, Adriana F. Paes Leme. Malignant and non-malignant cells from primary tumor and lymph node metastasis ecosystems show different behavior for patient-associated protein signatures 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 4541.
Abstract 4565: The functional role of atypical chemokine receptor 1 in immune cell regulation of breast cancer
Authors: Jenkins Brittany D. , Martini Rachel , Gardner Kevin , Monteil Michele , Deeb Dorrah , Newman Lisa , Davis Melissa 
Published: August 2019

Abstract
Breast cancer (BC) is a heterogeneous disease that leads to varied molecular subtypes and distinct clinical outcomes. Tumor heterogeneity, which is in part influenced by genetic ancestry, contributes to racial disparities in BC. This disparity has persisted for over 30 years, despite improvements in detection, screening, and treatment methods. When investigating race-specific differences in the breast tumor microenvironment (TME), we believe that chemokine receptors, such as atypical chemokine receptor 1 (ACKR1/DARC), play an integral role in regulating chemokine and immune cell migration in circulation and the TME, ultimately influencing tumor progression. ACKR1/DARC specifically plays a role in ancestry-related differences in BC due to an African-specific ancestral allele (“Duffy-null” mutation) that is fixed in Sub-Saharan African populations, and present in 60-70% of African-Americans. Those that harbor the mutation do not express ACKR1/DARC on erythrocytes, ultimately affecting immune cell migration in these populations only. To better understand the effects of this variant in circulation and the TME, we performed immunohistochemistry (IHC) on breast tumors from a cohort of patients with matched blood samples. From our IHC analysis, we quantified levels of ACKR1/DARC, in addition to levels of target pro-inflammatory chemokines, and distinct immune populations of T-cells and macrophages. In addition, individuals were genotyped to determine Duffy-null status, and a correlative Luminex multiplex assay was performed on patient plasma to determine concentrations of pro-inflammatory chemokines in circulation. We determined that those with low expression of ACKR1/DARC in tumors exhibited a unique signature of immune cell infiltrates that would encourage a more aggressive TME. In addition, we observed variable levels of circulating chemokines, where those with the Duffy-null mutation exhibited significantly decreased levels of CCL2. Overall, our analyses support the hypothesis that tumor-specific DARC/ACKR1 plays a vital role in immune cell regulation in women with BC.
Citation Format: Brittany D. Jenkins, Rachel Martini, Kevin Gardner, Michele Monteil, Dorrah Deeb, Lisa Newman, Melissa Davis. The functional role of atypical chemokine receptor 1 in immune cell regulation of breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4565.
Abstract 4596: Synthesis and biological evaluation of small molecules inhibitors targeting heterotrimeric Gαi2 protein
Authors: Caggia Silvia , Garrett Autumn S. , Kumar Aditi , Tapadar Subhasish , Oyelere Adegboyega K. , Venugopal Smrruthi Vaidegi , Khan Shafiq A. 
Published: August 2019

Abstract
Heterotrimeric G-proteins are ubiquitously expressed in cells, and they transduce signals from activated G-protein coupled receptors. It is well known that these proteins are differentially expressed in cancer, thereby activating signals that lead to different biological functions such as proliferation and cell motility. Previously, we have shown that Gαi2 protein is essential for cell migration and invasion in prostate cancer cell lines, and its action is downstream of PI3-kinase/Rac1 activation. We have also shown that in PC3 prostate cancer cells, pre-treated with Pertussis toxin (PTX), a well know inhibitor of Gαi/0, resulted in the attenuation of TGFβ1- and oxytocin-induced migration and PI3-kinase activation, without affecting EGF-induced PI3-kinase activation and cell migration. Here, we synthesized new small molecules inhibitors, GDIs, capable of preventing nucleotide exchange and subunit activation. Compounds #29 and #46 are analogs of the lead compound, lacking the thiophene OH-group and with a thiol- to N-methyl amino-group substitution, respectively. Compound #35, a methyl ether derivative of #46, is designed to test the effect of the modification to the phenolic group on Gαi2 inhibition activity. We pretreated PC3 cells with the small molecules and then stimulated with EGF and oxytocin to activate Gαi2 subunit. Immunoprecipitation of the active Gαi and western blot for Gαi2 showed a decrease in the amount of active Gαi2 that was pulled down compared with the controls. Using cell migration assay, we observed that #29 and #46, both at 10 μM, caused inhibition of migration in different prostate cancer cell lines in response to EGF treatments. In contrast, #35 is inactive in this assay at the same concentration. To determine if the effects of Gαi2 are the same in other cancer cells, we first knockdown Gαi2 protein expression in breast and ovarian cancer cells and performed migration assays. The knock-down of endogenous Gαi2 attenuated cell migration, compared to the control cells. We also performed migration assays in the same cells using compound #29 at 10 μM and observed significant inhibition of migratory behavior in response to EGF- and FBS stimuli compared to the controls. We conclude that the small molecules we used in this study may be considered as potential therapeutic tools, inhibiting the migratory capability of metastatic cells.
Citation Format: Silvia Caggia, Autumn S. Garrett, Aditi Kumar, Subhasish Tapadar, Adegboyega K. Oyelere, Smrruthi Vaidegi Venugopal, Shafiq A. Khan. Synthesis and biological evaluation of small molecules inhibitors targeting heterotrimeric Gαi2 protein [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 4596.
Abstract 46: 3D reconstruction and quantitative analysis of histology for prostate cancer
Authors: Ruusuvuori Pekka , Kartasalo Kimmo , Valkonen Mira , Valkonen Masi , Visakorpi Tapio , Nykter Matti , Latonen Leena 
Published: August 2019

Abstract
The integration of serial sectioning of tissue, digital whole slide imaging (WSI) and computational reconstruction algorithms enable the examination of histological samples in 3D at subcellular resolution. This allows visualizing and analyzing the imaged sample in its true three-dimensional context, offering a more comprehensive view on its spatial and morphological characteristics than that obtained via typical 2D examination. The advantages of reconstructing 3D models computationally using WSI over direct 3D imaging include the combination of high resolution, large sample sizes and compatibility with existing biochemical techniques such as in situ hybridization, immunohistochemistry and established histological staining and interpretation protocols.
For this purpose, we developed a software pipeline to perform routine 3D reconstruction tasks for large image sizes and datasets in a fully automatic manner. The steps in our 3D reconstruction process are image acquisition, alignment of images to a shared coordinate space, and visualization of the reconstructed 3D data. We optimized algorithm selection and computationally intensive hyperparameter tuning using a quantitative benchmarking framework and Bayesian optimization. Further, we applied our existing pipeline for feature based analysis of tissue and extended it into 3D, allowing quantification and visualization of hundreds of features characterizing the tissue.
We currently apply this system to characterize prostate cancer tumors. Prostate cancer is a heterogenous, often multifocal disease. In order to understand why and how certain tumor foci develop to a life-threatening disease over others, the tissue growth patterns and evolution of tumors with different genetic backgrounds need to be studied. We use mouse models of prostate cancer to study early tumor development connected to common genetic cancer alterations. By computing hundreds of features from the histology, and studying these in the spatial context, we gain important information of tumor characteristics as well as intra- and intertumor heterogeneity. In the future, we will further scale up the protocol to perform 3D reconstruction for serially sectioned human prostates in the near future.
Citation Format: Pekka Ruusuvuori, Kimmo Kartasalo, Mira Valkonen, Masi Valkonen, Tapio Visakorpi, Matti Nykter, Leena Latonen. 3D reconstruction and quantitative analysis of histology for prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 46.
Abstract 4602: Abi1 promotes breast cancer progression by regulating cell-matrix adhesion
Authors: Li Xiang , Regua Angelina , Bratslavsky Gennady , Kuznetsov Vladimir A. , Kotula Leszek 
Published: August 2019

Abstract
Breast cancer is one of the most common diagnosed cancers in the United States. There will be approximately 266,120 new breast cancer cases in the U.S. and over 40,000 patients are predicted to die from the malignant progression of their breast cancer tumors in 2018. Traditional therapeutic methods of the invasive breast cancer include surgery accompanied by chemotherapy. However, following the initial therapy patients often relapse and eventually die from tumor metastasis. Abl interactor 1, or Abi1, is an adaptor protein which regulates actin polymerization through participation in WAVE (Wiscott-Aldrich syndrome protein family verprolin homologous) complex. The WAVE regulatory complex (also called WRC), regulates actin based cellular behavior, such as cellular adhesion and cell migration, by activating Arp2/3 complex and promoting actin polymerization. Previous studies indicated the direct interaction between integrin α4 and Abi1, which suggests a potential role of Abi1 in regulating cell-matrix adhesion signaling by involved in the inside-out integrin signaling pathways. In order to test the above hypothesis, we developed two genetic engineered Abi1 knocked-out breast cell lines from either HER2+ breast cancer cell line SKBR3 or normal breast epithelial cell line MCF10A by using CRISPR-Cas9 technique. After confirming inactivation of Abi1 gene by Western blotting, DNA and RNA sequencing, cells were harvested and analyzed for integrins levels. Western blotting results indicated dysregulation of multiple integrins in the Abi1 knock-out cell lines. The results from subsequent immunofluorescence experiments of the Abi1 knock-out cell lines also suggested changes in cell-matrix adhesion signaling using staining for scaffold protein paxillin and phosphorylated Focal-Adhesion-Kinase (FAK) as readouts. Our findings suggest that Abi1 might functions as a key regulator in breast cancer tumor progression by playing an important role in regulating signal pathways in cell-matrix adhesion. Supported by the Carol Baldwin Foundation of CNY, and in part by NIH-NCI grant No. R01 CA161018.
Citation Format: Xiang Li, Angelina Regua, Gennady Bratslavsky, Vladimir A. Kuznetsov, Leszek Kotula. Abi1 promotes breast cancer progression by regulating cell-matrix adhesion [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 4602.
Abstract 4607: Androgen signaling is essential for prostate cancer development initiated from prostatic basal cells
Authors: He Yongfeng , Hooker Erika , Yu Eun-Jeong , Cunha Gerald R. , Liao Lan , Xu Jianming , Earl Andrew , Wu Huiqing , Gonzalgo Michael L. , Sun Zijie 
Published: August 2019

Abstract
Emerging evidence has shown that both prostatic basal and luminal cells are able to initiate oncogenic transformation. However, despite the diversity of tumor initiating cells, most prostate cancer cells express the androgen receptor (AR) and depend on androgens for their growth and expansion, implicating an essential role of androgen signaling in prostate tumorigenesis. Prostatic basal cells express p63 and are able to differentiate into luminal, neuroendocrine, and basal cells. In this study, we used a variety of relevant mouse models and in vivo systems to directly address the significance of androgen signaling in oncogenic transformation and tumor development initiated from prostatic p63-expressing cells. We demonstrate that activating Wnt oncogenic signaling by expressing stabilized b-catenin in prostatic p63-expressing cells is able to induce cell proliferation and the formation of atypical cell clusters in different prostatic lobes at embryonic, prepubescent, and adult stages. Intriguingly, despite the androgen insensitive nature of prostatic p63-expressing cells, androgens are still essential for these cells to grow and develop to androgen-dependent, luminal cell type prostate tumors. These findings are consistent with what have been observed in human prostate cancers, in which the majority of tumor cells are androgen-sensitive and possess luminal cell properties, providing new insight into the molecular mechanisms for prostate cancer initiation and progression.
Citation Format: Yongfeng He, Erika Hooker, Eun-Jeong Yu, Gerald R. Cunha, Lan Liao, Jianming Xu, Andrew Earl, Huiqing Wu, Michael L. Gonzalgo, Zijie Sun. Androgen signaling is essential for prostate cancer development initiated from prostatic basal 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 4607.
Abstract 4620: Development of orthotopic breast cancer brain metastasis patient-derived xenograft(PDX) model
Authors: Oshi Masanori 
Published: August 2019

Abstract
Background: The vast majority of the mortality of breast cancer results from distant metastasis and pre-clinical models are in critical need for effective drug development. Patient-derived xenograft (PDX) maintains the features of the donor tumors such as intra-tumor heterogeneity; however, PDX model of breast cancer brain metastasis that delivers stable consistent results is not popularized. We demonstrate our novel methods (coined “Oshi”method) used to develop an orthotopic brain metastasis patient-derived xenograft model (PDMOX) for breast cancer brain metastasis via tumor tissue implantation. Methods: Brain metastasis PDX were created using metastatic brain tumors from breast cancer patients and implanting them in the brain of NSG female mice. Tumors of ~1 mm3 were implanted mechanically minced tissue with medium. We implant the tissue through a frontal bone burr hole into the right caudate putamen. Tumor growth was monitored by magnetic resonance imaging (MRI). Results: “Oshi” method utilizes a pipette tip in order to inoculate tumor at the same depth. A minced tumor was instilled using a 23G needle as the “non-oshi” method. One hour post-surgical survival after implantation of minced tumor by “non-oshi” method was only 37.5% (3/8), whereas 100% (40/40) by the “Oshi” method. All tumors were well engrafted in surviving mice after both methods. There was larger variation in tumor growth after “non-oshi” (Median 20±25.0 day, range: 12-24 day. Tumor volume: median 5.6±21.0 mm3, range 2.8-48.7 mm3). One mouse developed ptosis, and 2 out of 3 mice that underwent the “non-oshi” method had sudden death. On the other hand, all mice that underwent the “Oshi” method lived until the tumor grew to 125-200 mm3 without neurological symptoms. The engraftment rate of Mincing tumor were 100% at 1.5 months after implantation, while the engraftment rate of Enzymatic digestion tumors was only 50% at 2 months. Mincing tumor had faster growth speed than the tumor of enzymatic digestion. The engraftment time of enzymatic digestion tumor was slower than other tumor tissue forms. All 3rd generation tumors could be detected at the point of 1month after implantation, on the other hand, it took 2 month to detect 1st generation tumors. The growth of 3rd generation tumors was significantly faster and bigger than others. Conclusion: Various surgical techniques used to generate PDMOX breast cancer models showed major differences in the tumors and outcomes. These novel models are expected to become powerful tools for preclinical studies in metastatic breast cancer.
Citation Format: Masanori Oshi. Development of orthotopic breast cancer brain metastasis patient-derived xenograft(PDX) 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 4620.