bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 2001: Transcriptional integrator p300 in human prostate tumor-initiating cells
Authors: Gruber Martina , Handle Florian , Culig Zoran 
Published: August 2018

Abstract
Introduction
p300 is a well-known coactivator of the androgen receptor (AR) and has been shown to play an important role in prostate cancer (PCa). The expression of p300 has been correlated to tumor volume and PCa progression. Therefore, we hypothesize that p300 may play an important role in tumor-initiating cells and therapy resistance. Due to its multifunctional role p300 may serve as a promising new therapeutic target for treatment of PCa. Ultimately, it is our aim to find new innovative therapeutic targets for castration resistant PCa.
Material & Methods
The tumor-initiating capacity of the AR-negative PCa cell lines PC3 and Du145, as well as primary prostate epithelial cells was characterized by seeding a limiting number of cells per flask. Colony formation efficiency, colony type and detailed morphological information about each colony were determined by an automated pipeline that we have developed. Stable cell lines with doxycycline inducible p300 sh RNAs were generated by lentiviral transduction. Knockdown of p300 was verified by Western Blot and reduced p300 activity was confirmed by measuring histone h3 acetylation.
Results
In concordance with the literature we identified three colony types (holo-, mero- and paraclones) in PC3 and Du145 cell lines as well as primary PCa cells. Serial clonogenic assays confirmed in both cell lines that holoclones show the highest colony formation potential and maintain their tumor-initiating capacity over numerous rounds. In PC3 we detected 10% and in Du145 30% holoclones. Under optimal growth conditions p300 was detected in all colony types, however no differences in protein expression of p300 as well as on mRNA level were observed. Knockdown of p300 did not alter colony formation efficiency or the relative distribution of colony types.
Conclusion
Taken together, we confirmed the presence of tumor-initiating holoclones in PCa cell lines and primary prostate epithelial cells and established stable cell lines with inducible knockdown of p300. In contrast to several other types of malignancies, p300 has no specific role in regulation of stemness in our PCa models at the tested conditions. As a next step we will determine the effects of p300 knockdown during chemotherapy and radiation therapy to evaluate if p300 depletion may enhance the treatment efficacy and which role p300 plays in therapy resistance.
Citation Format: Martina Gruber, Florian Handle, Zoran Culig. Transcriptional integrator p300 in human prostate tumor-initiating cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2001.
Abstract 2004: Identification of MLK4 as a novel regulator of cancer stem cells in triple-negative breast cancer
Authors: Lin Chang-Ching , Lo Miao-Chia , Moody Rebecca , Stevers Nicholas , Tinsley Samantha , Gasparyan Mari , Wicha Max , Sun Duxin 
Published: August 2018

Abstract
Cancer stem cells (CSCs) are a small population of cancer cells that are capable of self-renewal and tumor initiation. As a result, targeting CSCs is a potential therapeutic strategy for preventing cancer relapse and metastasis. Mixed lineage kinase 4 (MLK4), a serine/threonine kinase, is known to regulate mesenchymal glioma stem cells and to drive tumorigenesis in colorectal cancer. We found that MLK4 was highly expressed in triple-negative breast cancer (TNBC) compared to other breast cancer subtypes according to the database from The Cancer Genome Atlas. Furthermore, multiple datasets indicated that higher expression of MLK4 was associated with poor prognosis in breast cancer. Despite the correlation of MLK4 and clinical outcome, the function of MLK4 in breast cancer is still not known. In this study, we found that knockdown of MLK4 significantly decreased secondary mammosphere formation, the CD44+/CD24- CSC population, invasion and migration in TNBC cell lines. In addition to suppressing CSC phenotypes in vitro, knockdown of MLK4 also inhibited tumor growth in NOD/SCID mice. Secondary transplantation of tumor cells demonstrated that silencing of MLK4 significantly decreased tumor-initiating cell frequency. As accessed by qPCR, knockdown of MLK4 led to decreased expression of mesenchymal genes (CD44 and VIM) and concomitant increased expression of epithelial genes (CDH1 and claudin genes). Immunohistochemical staining revealed that knockdown of MLK4 in xenografts resulted in increased expression of CK19, a luminal-epithelial marker. These studies indicate that MLK4 plays an important role in the function of mesenchymal-like CSCs in TNBC. Silencing of MLK4 in TNBC cell lines can transform CSC in these tumors to a more differentiated epithelial cell state. Together, these studies identify that MLK4 is a potential therapeutic target for CSCs in TNBC.
Citation Format: Chang-Ching Lin, Miao-Chia Lo, Rebecca Moody, Nicholas Stevers, Samantha Tinsley, Mari Gasparyan, Max Wicha, Duxin Sun. Identification of MLK4 as a novel regulator of cancer stem cells in triple-negative breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2004.
Abstract 2005: CSCs induced from iPSCs indicate the trace of cancer cell culture conditioned media
Authors: Seno Akimasa , Kasai Tomonari , Tokutaka Heizo , Seno Masaharu 
Published: August 2018

Abstract
Cancer stem cells (CSCs) show drug resistance and could be a source of cancer cells. Although these cells are recently considered more important than ever in cancer studies, the extremely small number of CSCs in actual cancer tissues makes the analysis difficult. Previously, we demonstrated that CSCs could be differentiated from induced pluripotent stem cells (iPSCs) in the presence of cancer cell conditioned media. We have confirmed the conditioned media from various types of cancer cell lines were successful to convert iPSCs into CSCs showing self-renewal property, differentiation potential, and tumorigenicity. To identify their differences between the generated CSCs, gene expression was compared by spherical self-organizing map (sSOM). Comparing with more than 1000 cells including stem cells, induced CSCs, CSCs obtained from cancer tissue or cancer cell line, and cancer cells or cancer tissues, known cancer stem cell markers were found not enough to classify CSCs. In the sSOM analysis, “ideal probe” (IP), which was supposed to characteristically be expressed in each group, was set to nomiate the marker gene. The distance close to the IP depicted some candidate marker genes in each group. The gene expression commonly shared among different types of CSCs was also searched. This IP revealed known cancer related gene Endthelin 1 as a commonly expressed gene. Moreover, when the CSCs were compared with the parental hiPSC and cancer cells, of which conditioned media was used for the conversion, sSOM showed that CSCs were not always differentiated towards their origin, but which genes should be responsible for generating CSCs. These results indicate that the induced CSCs should be the initial state of cancer cells and imply some important role of Endothelin 1 in CSC development.
Citation Format: Akimasa Seno, Tomonari Kasai, Heizo Tokutaka, Masaharu Seno. CSCs induced from iPSCs indicate the trace of cancer cell culture conditioned media [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2005.
Abstract 2006: Tobacco smoke-induced Marcks phosphorylation promotes inflammatory and stemness properties in lung cancer
Authors: Yang David C. , Wu Yichin , Huang Mu-Jen , Pinkerton Kent E. , Wu Reen , Chen Ching-Hsien 
Published: August 2018

Abstract
Exposure to tobacco smoke is a major risk factor associated with lung cancer development and progression; however, the mechanisms of how tobacco smoke activates pathways promoting cancer malignancy remain to be established. Previously, phosphorylation of MARCKS at Ser159/163 (phospho-MARCKS) was shown to promote malignancy of neoplastic disease, but it is still unclear how phospho-MARCKS is upregulated in lung cancer. Herein, we investigated if phospho-MARCKS is elevated in response to smoke exposure and plays a key role in smoke-related lung cancer. In a screen of 200 patients with lung cancer, we confirmed that strong phospho-MARCKS staining was observed in lung cancer specimens from smokers and was positively correlated, as compared to non-smokers. In addition, we demonstrated that increased smoking pack-year was noted in lung cancer patients with high phospho-MARCKS. Surprisingly, there is an apparent trend that patients with both tobacco use and high phospho-MARCKS levels had the worst overall survival. MARCKS was found to become activated in airway epithelium and lung cancer in response to smoke both in vitro and in vivo. MARCKS inhibition significantly attenuated smoke-induced oncosphere formation and migratory capability. Mechanistically, upregulation of phospho-MARCKS by smoke occurred in parallel with increased inflammatory cytokine expression (e.g. TNF-α, IL-8) and stemness marker expression (e.g. Oct4, Nanog, CD133, Sox2). Conversely, targeting of MARCKS phosphorylation with the MPS peptide resulted in down-regulation of smoke-induced stemness and cytokine genes. Our data suggests that phospho-MARCKS plays a role in modulating smoke-mediated lung cancer progression and is a potential prognostic biomarker in smoke-related lung cancer.
Citation Format: David C. Yang, Yichin Wu, Mu-Jen Huang, Kent E. Pinkerton, Reen Wu, Ching-Hsien Chen. Tobacco smoke-induced Marcks phosphorylation promotes inflammatory and stemness properties in lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2006.
Abstract 2018: Rescue of ΔNp63α inhibits urothelial cell invasion by attenuating epithelial-to-mesenchymal transition (EMT)
Authors: Srivastava Kirtiman , Smith Victoria , Fernandez Eric A. , Breen Conor , McCloskey Karen D. 
Published: August 2018

Abstract
Background: Loss of the transcription factor, p63 is associated with poor prognosis in muscle-invasive bladder cancers. The current study aimed to investigate the tumor-suppressive role of p63 in urothelial cancers.
Methods: A 3-dimensional (3D) organotypic raft model of urothelial cancer was established by culturing human urothelial cancer cell lines (HT1376, T24) on human bladder fibroblast-embedded collagen-I. Control rafts contained normal primary human urothelial cells (HUC). Cells were also cultured as monolayers on collagen-I coated dishes before harvesting total RNA and protein for qPCR and Western blot analyses respectively.
Results: Non-invasive HUC and HT1376 had an epithelial phenotype, characterized by compact and cuboidal morphology whereas invasive T24 cells were elongated with a spindle morphology, typical of mesenchymal cells and indicative of epithelial-to-mesenchymal transition (EMT), which is necessary for invasion. The number of invasive incidents in 3D rafts established with T24 cells was higher compared to those with HUC or HT1376 cells (N=3, p&lt;0.05). Consistent with this, the invasive cell line had reduced mRNA and protein expression of total p63 (N=3), a differentiation marker, and the epithelial marker E-cadherin (N=3), in addition to upregulated expression of the mesenchymal markers N-cadherin (N=3) and fibronectin (N=3) and pERK-Y204 (N=2) compared to the non-invasive cells.
Treatment of invasive T24 cells with histone deacetylase (HDAC) inhibitors (vorinostat (pan) or entinostat (HDAC1,3)) attenuated the number of invasive incidents (N=3, p&lt;0.05), and restored protein expression of total p63 (N=3) and E-cadherin (N=2) while normalizing pERK-Y204 (N=2 for T24). The tumor-suppressive properties of the ΔNp63α isoform were studied by adenoviral-mediated overexpression of ΔNp63α in T24 cells, which mimicked the effects of HDAC inhibitors and diminished EMT by rescuing E-cadherin expression while depleting fibronectin (N=2). Overexpression of ΔNp63α also reduced the number of invasive incidents in 3D models established with T24 cells (N=2).
Conclusion: Invasive T24 cells exhibited an EMT phenotype, which coincided with depleted p63 expression. Rescue of ΔNp63α expression by treatment with HDAC inhibitors or through experimental overexpression attenuated the EMT phenotype and cell invasion.
Citation Format: Kirtiman Srivastava, Victoria Smith, Eric A. Fernandez, Conor Breen, Karen D. McCloskey. Rescue of ΔNp63α inhibits urothelial cell invasion by attenuating epithelial-to-mesenchymal transition (EMT) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2018.
Abstract 2020: SAHA and EGCG affect metastatic potential to varying degrees in three triple-negative breast cancer cell lines
Authors: Lewis Kayla A. 
Published: August 2018

Abstract
Although triple-negative breast cancers (TNBC) have distinct molecular aberrations, tumors of the same histological grade may have dramatically different responses to the same therapy. TNBC tumors are basal-like, aggressive, and harbor a proclivity to metastasize to the brain and lungs. By modifying the cancer epigenome we have shown it is possible to reduce the metastatic potential of triple-negative breast cancer. Suberoylanilide hydroxamic acid (SAHA, clinically Vorinostat) is a histone deacetylase (HDAC) inhibitor, and epigallocatechin-3-gallate (EGCG) is a green tea polyphenol that acts as a DNA methyltransferase (DNMT) inhibitor. In combination, we found that 3 μM SAHA and 5 μM EGCG alter mammosphere formation, and the expression of E-cadherin and N-cadherin, which are genes involved in the epithelial-to-mesenchymal transition (EMT). Epigenetic enzyme activity was also assessed to determine if SAHA and EGCG were capable of modulating the functionality of DNMTs and HDACs. Because our previous work has identified a decrease in cellular viability with the combination of SAHA and EGCG, we aimed to investigate the effect on cell cycle arrest and genes involved in cell cycle progression. Our prior findings have indicated that the combination of SAHA and EGCG decreases the expression level of miR-221/222, which is known to directly inhibit translation of p27 and PTEN. p27 is involved in regulating the transition from G1 to S phase, and with the combination of SAHA and EGCG the expression of p27 was significantly increased, suggesting potential cell cycle arrest between G1 and S phase. Because the PTEN/Akt pathway plays a role in progression from G1 to S phase through p-Akt, we also investigated changes in the expression of PTEN with SAHA and EGCG. Together our findings are reflective of tumor heterogeneity; despite the same breast cancer subtype they respond differently to chemotherapeutics. Further studies will include research into specific epigenetic modifications associated with the epithelial-like reversion seen in this project.
Citation Format: Kayla A. Lewis. SAHA and EGCG affect metastatic potential to varying degrees in three triple-negative breast cancer cell lines [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2020.
Abstract 2037: E-cadherin enhances immune control of metastatic melanoma
Authors: Shields Bradley D. , Koss Brian , Mahmoud Fade , Byrum Stephanie D. , Tackett Alan J. 
Published: August 2018

Abstract
The advent of checkpoint blockade therapies has transformed the clinical management of metastatic melanoma. These monoclonal antibodies, targeted against CTLA-4 and PD-1, have shown durable and long-lasting responses in a subset of melanoma patients. However, response rates remain incomplete, even when using combination therapy (CTLA-4 plus PD-1). Identifying predictive or controlling features of responsiveness has been urgent goal in oncology research. Our group and others have previously shown responding tumors display high levels of E-cadherin, a cell-cell adhesion molecule which defines an epithelial-like phenotype. The varying clinical responses observed to checkpoint blockade in metastatic melanoma, paired with the knowledge that E-cadherin expression correlates with such responses, provides impetus to study the significance of E-cadherin in the context of checkpoint blockade. Here, we present a novel B16F10 melanoma mouse model in which E-cadherin is exogenously expressed (B16.E-cad). The parental B16F10 line does not express E-cadherin and is poorly immunogenic and notoriously resistant to treatment with immune checkpoint inhibitors. Thus, B16.E-cad and the vector control model epithelial-like (responsive) and mesenchymal-like (non-responsive) phenotypes respectively. We find, compared to vector control, B16.E-cad exhibits delayed tumor growth, reduced metastatic potential, and increased overall survival in vivo, despite similar proliferation rates in vitro. Analysis of immune cell infiltration (FACS) performed on tumors grown in C57/BL6 mice revealed no differences between vector, B16.Ecad and B16.SIY. Conversely, transplantation of B16.E-cad into Rag1-/-mice abrogated tumor growth delay indicating an immune-mediated tumor response. Additionally, B16.Ead tumors displayed greater responses to combination checkpoint inhibitor therapy. Further, imunohistochemistry for E-cadherin performed on patient pretreatment tumor biopsies revealed negative staining was predictive of a non-responsive status. These data indicate an epithelial-like phenotype in melanoma tumors facilitates tumor immunosurveillance and responsiveness to immune checkpoint blockade.
Citation Format: Bradley D. Shields, Brian Koss, Fade Mahmoud, Stephanie D. Byrum, Alan J. Tackett. E-cadherin enhances immune control of metastatic melanoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2037.
Abstract 2044: Lymphatic vessel endothelial hyaluronan receptor-1 (LYVE-1) modulates VEGF-C and VEGF-D secretion in the triple negative breast cancer cell line MDA-MB-231
Authors: Caceres Sara , Little Andrew C. , Yates Joel A. , Gilani Rabia A. , Merajver Sofia D. 
Published: August 2018

Abstract
Breast cancer commonly gives rise to lymph node metastases, and it has been suggested that tumor cell migration is facilitated by the generation of new lymphatic vessels, or lymphangiogenesis. Lymphatic endothelial cell hyaluronic acid receptor 1 (LYVE-1) is a hyaluronic acid (HA) receptor commonly used as a lymphatic vessel endothelial marker. LYVE-1 has been observed in a variety of breast cancer epithelial cells, and its lymphangiogenic function remains unclear. LYVE-1 has been casually linked to the vascular endothelial growth factors VEGF-C and VEGF-D, which are well appreciated for their roles in lymphangiogenic responses. Therefore, we hypothesize that LYVE-1 may impact lymphangiogensis via a VEGF-C/VEGF-D mediated pathway. We utilized LYVE-1-targeted RNAi in MDA-231 cells followed by HA stimulation and measured production and secretion of both VEGF-C and VEGF-D by western blot and ELISA, respectively. Surprisingly, LYVE-1 knockdown resulted in elevated levels of basal VEGF-C secretion, while LYVE-1 knockdown followed by HA stimulation decreased secreted levels of VEGF-C, with no observed changes in intracellular levels when compared to their controls. Conversely, LYVE-1 knockdown displayed no significant changes in basal VEGF-D levels, although, secreted VEGF-D levels were elevated following HA stimulation. Collectively, our preliminary findings suggest that LYVE-1 modulates VEGF-C/D secretion, potentially defining a novel function for LYVE-1 in MDA-231 triple negative breast cancer epithelial cells.
Citation Format: Sara Caceres, Andrew C. Little, Joel A. Yates, Rabia A. Gilani, Sofia D. Merajver. Lymphatic vessel endothelial hyaluronan receptor-1 (LYVE-1) modulates VEGF-C and VEGF-D secretion in the triple negative breast cancer cell line MDA-MB-231 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2044.
Abstract 2045: Mechanistic insights into the role of cAMP-regulated EPAC1 in tumor-induced angiogenesis and metastatic potential in triple-negative breast cancer
Authors: Dhandapani Muthu , Goldman Aaron , Kumar Naveen , Prasad Peeyush , Jash Eshna , Singh Itender , Gopinath Kodaganur S. , S Krishnamurthy , P Prabhusankar , Sehrawat Seema 
Published: August 2018

Abstract
Background: Breast cancer is the leading cause of cancer-related mortality in women. Triple negative breast cancer (TNBC) is one of most aggressive subtypes, which is often accompanied by metastasis, a feature that requires development of new blood vessels (neovasculature) to disseminate tumor cells throughout the body. We recently reported that down-regulation of exchange factor directly activated by Cyclic AMP (cAMP), also known as EPAC1, leads to a reduction in proliferation and inhibition of cell migration.
Methods: Here, using gene knockdown by siRNA and a 3-dimensional in-vitro TNBC co-culture model with Human Vascular Endothelial Cells (HUVECs), we studied microvascular density and the role of EPAC1. Angiogenesis proteome profiling was employed to examine protein networks that were regulated by EPAC1 in the TNBC cell line, MDA-MB-231. Immunofluorescence along with Electric cell-substrate impedance sensing (ECIS) was used to study vascular permeability. To confirm these findings in a translational context, we employed a human tumor explant assay that predicts clinical response to therapy (CANscriptTM) and studied CD34+ nodes to determine how neovasculature associates to drug response.
Results: We determined that downregulation of EPAC1 in the TNBC cell line, MDA-MB-231, leads to reduction of proteins involved in cell migration, metastasis, angiogenesis and adhesion. Interestingly, we determined that loss of EPAC1 leads to increased expression of negative regulators in these same pathways. Immunofluorescence imaging showed that EPAC1 downregulation in MDA-MB-231 cells leads to diminished expression of proteins such as Paxillin, MENA, MMP-9 and tubulin. indicated that EPAC1 role in vascular permeability. Finally, CANscriptTM demonstrated a link between response to therapy and microvascular density, which was reduced under drug pressure in patients that were predicted to respond to treatment.
Conclusion: Our results suggest that EPAC1 is a driver of microvascular density in the tumor microenvironment, a feature that may play a key role in distant metastasis and therapy failure. Ex-vivo modeling of neovasculature may be a novel strategy to predict clinical response and distant metastasis.
Citation Format: Muthu Dhandapani, Aaron Goldman, Naveen Kumar, Peeyush Prasad, Eshna Jash, Itender Singh, Kodaganur S. Gopinath, Krishnamurthy S, Prabhusankar P, Seema Sehrawat. Mechanistic insights into the role of cAMP-regulated EPAC1 in tumor-induced angiogenesis and metastatic potential in triple-negative breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2045.