bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 239: Alteration of drug sensitivity according to the induction and reversion of epithelial-to-mesenchymal transition (EMT) in human lung adenocarcinoma cell lines harboring an EGFR mutation
Authors: Kurimoto Ryota , Iwasawa Shunichiro , Ebata Takahiro , Ishiwata Tsukasa , Sekine Ikuo , Tada Yuji , Tatsumi Koichiro , Koide Shuhei , Iwama Atsushi , Takiguchi Yuichi 
Published: July 2016

Abstract
Introduction: EMT phenotype is known to relate to drug resistance and immune tolerance of cancer. However, mechanism underling these phenomena, including the mechanism of the induction and reversion of EMT, are not fully understood.
Methods: EGFR mutated human lung adenocarcinoma cell lines, HCC-827 and PC-9, were treated with TGF-ß and/or FGF-2 to induce EMT. EMT was reversed by treating the induced EMT cells with either of PP242 (mTOR inhibitor), metformin and DMSO. The phenotypic alterations according to the induction and reversion of EMT were accessed by a wound healing assay for mobility, flow cytometry for cell cycle, MTT and apoptosis assays for drug sensitivity to cisplatin and gefitinib, and RT-PCR and fluorescence IHC for PD-L1 expression.
Results: The treatment with combination of TGF-ß/FGF-2 showed an efficient increase in expressions of mesenchymal markers and slug in both cell lines, and a decrease in E-cadherin expression in HCC827. In immunoblotting analyses, the Smad3 pathway in PC-9, and the Smad3, MEK/Erk and mTOR pathways in HCC-827 were involved in the induction of the EMT. The induced EMT was accompanied by enhanced cell motility and accumulation in the G0/G1 phases in both cell lines. The induced EMT also made the cells less sensitive to gefitinib in both cell lines, and to cisplatin in HCC-827. Increased PD-L1 expression was observed in both cell lines. Treatment of the induced EMT cells with PP242, metformin and DMSO reverted the altered expressions of epithelial and mesenchymal markers, cell motility and cell cycle. These agents reverted the EMT to different extents and through different pathways, depending on the cell lines. Reversion of the EMT using each of the 3 agents partly restored drug sensitivity, and suppressed PD-L1 expression.
Conclusion: Inducing EMT by treatment with TGF-ß/FGF-2 is an effective way to acquire drug resistance and up-regulation of PD-L1. Reversion of the EMT, therefore, has a potential to overcome drug resistance and immune tolerance of cancer.
Citation Format: Ryota Kurimoto, Shunichiro Iwasawa, Takahiro Ebata, Tsukasa Ishiwata, Ikuo Sekine, Yuji Tada, Koichiro Tatsumi, Shuhei Koide, Atsushi Iwama, Yuichi Takiguchi. Alteration of drug sensitivity according to the induction and reversion of epithelial-to-mesenchymal transition (EMT) in human lung adenocarcinoma cell lines harboring an EGFR mutation. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 239.
Abstract 2393: Kidneys of VHL patients reveal the origin of renal clear cell carcinoma
Authors: Mubarak Mayyan , Sommaruga Samuel , Voigt David , Xu Xiacao , Kim Steve , Song Ailin , Vortmeyer Alexander O. 
Published: July 2016

Abstract
VHL disease is a classic tumor suppressor gene syndrome characterized by development of specific types of tumors in selective organs with nervous system and kidney being most consistently affected. Detailed studies on human spinal cord and cerebellum have previously revealed earliest stages of CNS tumorigenesis and the morphologic sequence resulting in development of frank tumors.
To elucidate earliest stages of renal clear cell carcinoma, we performed a similar approach in kidney tissues of four VHL patients and three sporadic control cases. From all cases, blocks of interest were procured, followed by serial sectioning and 3dimensional reconstruction of potential precursor lesions. The results reveal an abundance of foci with aberrant mesonephric clear cell proliferations that initially develop along the tubular lining, but have the potential to aggregate within individual tubules. This stage is followed by microscopic invasive clear cell aggregations which represent tumor precursor structures.
This study presents evidence for a consistent morphologic sequence for renal clear cell carcinogenesis. Molecular analysis of early steps within this sequence will allow for identification of earliest genetic and proteomic changes in the future. Therapeutic targeting of earliest changes may allow to develop preventive strategies for renal cancer development for VHL patients, potentially also for the non-VHL population.
Citation Format: Mayyan Mubarak, Samuel Sommaruga, David Voigt, Xiacao Xu, Steve Kim, Ailin Song, Alexander O. Vortmeyer. Kidneys of VHL patients reveal the origin of renal clear cell carcinoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2393.
Abstract 240: Functional significance of co-occurring mutations in PIK3CA and MAP3K1 in breast cancer
Authors: Avivar-Valderas Alvaro , McEwen Robert , Taheri-Ghahfarokhi Amir , Ahmed Ambar , Stetson Daniel , Dougherty Brian , Maresca Marcello , Hudson Kevin , Cruzalegui Francisco 
Published: July 2016

Abstract
PI3Kα signalling pathway is frequently hyper-activated in breast cancer (BrCa) with mutations of PIK3CA (∼45%) frequently found in luminal A BrCa samples. Genomic studies have also uncovered inactivating mutations in MAP3K1 (13-20%) and MAP2K4 (∼8%), two upstream kinases of the JNK apoptotic pathway in luminal A BrCa samples and co-occurring mutation of PIK3CA and MAP3K1 are found in ∼11% of PIK3CA mutants (TCGA). How these two alterations cooperate to promote tumorigenesis and impact the sensitivity to PI3Kα(AZD8835) and AKT (AZD5363) inhibitors is currently unknown. Using siRNA targeting and precise gene editing we have knocked down MAP3K1 in PIK3CA mutant cell lines to create in vitro models reflecting the mutational status of PIK3CA and MAP3K1 in BrCa patients. MAP3K1-deficient cells exhibited increased proliferation rate and decreased sensitivity to AZD8835 compared with parental control cells. In addition, mechanistic analysis revealed that siRNA mediated depletion of MAP3K1 enhances AKT phosphorylation and downstream signalling (i.e. pPRAS40, pFoxO1/FoxO3a) and provides resistance to AZD8835-mediated pathway inhibition. Using in vitro 3D-breast cancer organoid models we have found that MAP3K1 depletion increases overall acinar volume and counteracts AZD8835-mediated reduction of acinar growth. MAP3K1 deficient acini exhibited high pAKT levels in the presence of AZD8835 compared with control acini validating observations in 2D. Remarkably, whereas in control acini pAKT+ cells were restricted to the basal compartment, MAP3K1 deficient acini also exhibited pAKT+ cells in the luminal compartment suggesting anoikis resistance which is a hallmark in early stages of tumorigenesis. Elucidating the mechanistic basis for these clinically co-occurring mutations will provide insights into the mechanisms contributing to the oncogenic role of the PI3K pathway and future patient selection strategies.
Citation Format: Alvaro Avivar-Valderas, Robert McEwen, Amir Taheri-Ghahfarokhi, Ambar Ahmed, Daniel Stetson, Brian Dougherty, Marcello Maresca, Kevin Hudson, Francisco Cruzalegui. Functional significance of co-occurring mutations in PIK3CA and MAP3K1 in breast cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 240.
Abstract 2404: Dysregulation of lung developmental pathways associated with LKB1 loss in lung cancer
Authors: Kaufman Jacob M. , Lowe Cindy , Harris Bradford , Boyd Kelli , Amann Joseph , Eisenberg Rosana , Carbone David , Massion Pierre 
Published: July 2016

Abstract
Loss of the LKB1 tumor suppressor influences differentiation phenotypes in mouse models of lung adenocarcinoma and in human tumors. We utilize molecular data from resected human lung adenocarcinomas characterized by the TCGA to demonstrate that LKB1 deficient tumors exhibit a higher prevalence of neuroendocrine and gut-like differentiation markers than do LKB1 wild-type tumors (41% vs 9%, odds ratio = 7.3, P = 5.9E-19 for neuroendocrine differentiation; 36% vs 12%, odds ratio = 4.3, P = 2.5E-11 for gut-like differentiation. Fisher's exact test). Using copy number analysis and transcription factor enrichment analysis, we link these phenotypes to activation of particular transcription factors, namely FOXA2, HNF1A, ASCL1, and TTF1. We observe similar associations among non-small cell lung cancer cell lines, which may represent appropriate ideal models for further experimentation. Furthermore, we examine these differentiation phenotypes using immunohistochemical analysis of a tissue microarray (TMA), combined with RNAseq expression analysis, and MS/MS proteomic characterization of the same cohort of 36 tumors. Our molecular characterization confirms the neuroendocrine and gut-like differentiation phenotypes observed in the TCGA dataset and their association with LKB1-loss. Moreover, our immunohistochemical analysis demonstrates that these distinct differentiation subtypes are heterogeneously expressed within single tumors. Co-expression of neuroendocrine, gut-like, and respiratory differentiation is significantly more likely to occur within LKB1 deficient tumors, and is also associated with increased expression of a c-Kit positive sub-population that appears to lack expression of more differentiated markers. Among the TCGA tumors, this tri-lineage expression pattern is seen in 12.5% of LKB1-deficient tumors, compared to 1% of LKB1-wild-type tumors (Odds ratio 11.5, P = 3.2E-8. Fisher's exact test). These findings give further support to the role of LKB1 in regulating differentiation phenotypes in lung cancer, and may suggest a hierarchy of progenitor cells and lineage-specific subpopulations within these tumors.
Citation Format: Jacob M. Kaufman, Cindy Lowe, Bradford Harris, Kelli Boyd, Joseph Amann, Rosana Eisenberg, David Carbone, Pierre Massion. Dysregulation of lung developmental pathways associated with LKB1 loss in lung cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2404.
Abstract 2412: Reconstructing intratumor heterogeneity: lessons from therapeutic intervention in patient-specific models
Authors: Schumacher Dirk , Boehnke Karsten , Keil Marlen , Silvestri Alessandra , Silvestrov Maxine , Hoffman Jens , Fichtner Iduna , Schaefer Reinhold , Regenbrecht Christian RA 
Published: July 2016

Abstract
Precision medicine approaches seeking to predict individual susceptibility to single or combinatorial drugs for advanced and/or metastasized solid cancers heavily depend on biological model systems that maintain key morphological, phenotypic and genomic features of the original tumor.
Here, we present a case study of a female patient with metastasized colorectal cancer. Using tissue from five distinct areas of the primary tumor and its metastasis of the synchronously removed primary tumor and liver metastasis, we generated cell cultures. To address cell morphology and phenotypic features we performed immunohistochemistry (IHC) and immunofluorescence imaging showing that these cell cultures express colon-specific marker proteins/combinations CDX2 and CK20+/CK7-. Ultra-deep panel sequencing of original tumor tissue samples revealed damaging mutations in KRAS (G12D), PIK3CA (H1047R) and TP53 (C242F). Two cell cultures showed an additional SNP in the tumor suppressor SMAD4 (R361H), which was not detected in the original tissue, thus hinting at the existence of a small sub-population of cancer cells with a divergent mutation pattern.
In parallel we established patient-derived xenografts (PDX) models from each region and investigated the response to targeted therapeutics, aiming at key molecules of the MAPK, PI3K/AKT and mTOR pathways in these genetically heterogeneous populations. drug response in single and mixed cell populations to address differential growth characteristics and response to mono- and combinatorial drug treatment. To distinguish the cells-of-origin and to calculate distributions/contribution of each population to the in vivo tumor growth in this model, sub-populations were color-coded using lentiviral constructs, expressing either a green or red tag. FACS analyses after treatment were performed and ratios of SMAD4mut(green) vs. SMAD4wt(red) were determined for each PDX tumor. These analyses, together with confirmatory IHC staining for the respective tag, showed significant effects on both tumor growth and population distributions in a treatment-dependent manner, advocating for systematic evaluation of combinatorial treatment in patients.
Citation Format: Dirk Schumacher, Karsten Boehnke, Marlen Keil, Alessandra Silvestri, Maxine Silvestrov, Jens Hoffman, Iduna Fichtner, Reinhold Schaefer, Christian RA Regenbrecht. Reconstructing intratumor heterogeneity: lessons from therapeutic intervention in patient-specific models. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2412.
Abstract 2433: Loss of chd5-mediated gene repression synergizes with MYCN to accelerate neuroblastoma tumorigenesis in zebrafish
Authors: Zimmerman Mark W. , He Shuning , Shin Jimann , Zhu Shizhen , Guo Feng , Mansour Marc , Reyon Deepak , Joung J Keith , Quan Jinhua , Yusufzai Timur , Look A Thomas 
Published: July 2016

Abstract
Neuroblastoma is a malignancy of the peripheral sympathetic nervous system (PSNS) and accounts for 10-15% of cancer deaths among children. For the 40% of patients presenting with high-risk disease, current therapeutic approaches are insufficient and long-term survival is less than 50%. Along with genomic amplification of the MYCN oncogene, hemizygous loss of the 1p36 chromosomal region is a major risk factor in neuroblastoma. The human CHD5 gene is a neuronal specific chromatin remodeling helicase that maps to 1p36, and is thus frequently lost in high-risk neuroblastoma. Our laboratory has previously generated a faithful model of pediatric neuroblastoma in the zebrafish driven by overexpression of the MYCN oncogene in the PSNS (dbh:MYCN). Additionally, zebrafish chd5 mutant alleles were created using the newly developed gene editing technologies TALEN and CRISPR-Cas9. The resulting chd5 mutant fish exhibit abnormal development of the PSNS in the form of expansion of the superior cervical ganglia and enlargement of the interrenal gland (adrenal medulla). Haploinsufficiency for Chd5 combined with dbh:MYCN expression accelerates the onset and increases the penetrance of neuroblastoma tumorigenesis in zebrafish, indicating a tumor suppressive function. Elevated p-ERK and PCNA+ cells in tumor tissue indicates that loss of Chd5, cooperates with MYCN overexpression to accelerate neuroblast proliferation in vivo. Chd5 (in addition to Chd3 and Chd4) is a core member of the epigenetic regulatory NuRD complex, which also contains HDAC1-2, MTA1-3, MBD2-3, GATAD2A/B and RBBP4/7. The conserved biological function of Chd5 is to silence gene expression through the maintenance of a repressed chromatin state. Tumors deficient for Chd5 expression exhibit reduced levels of the H3K27me3 histone modification, a marker of facultatively repressed genes. Future studies will further explore the mechanism and function of Chd5 so that the pathways mediating tumor suppression can be elucidated and that essential proteins in these pathways can be targeted in ways that exploit the synthetic lethal relationships that are established.
Citation Format: Mark W. Zimmerman, Shuning He, Jimann Shin, Shizhen Zhu, Feng Guo, Marc Mansour, Deepak Reyon, J Keith Joung, Jinhua Quan, Timur Yusufzai, A Thomas Look. Loss of chd5-mediated gene repression synergizes with MYCN to accelerate neuroblastoma tumorigenesis in zebrafish. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2433.
Abstract 2438: Genome-wide screen reveals a role for glucocorticoids in B cell development that can be exploited to improve treatment of B cell acute lymphoblastic leukemia
Authors: Pufall Miles , Kruth Karina , Tasian Sarah K. 
Published: July 2016

Abstract
Glucocorticoids (GCs) are a component of highly effective therapy for B cell acute lymphoblastic leukemia (B-ALL), the most common childhood cancer. Although successful in 90% of patients, the prognosis for the remaining 10% is dismal. Because sensitivity to GCs alone predicts outcome well, we hypothesized that enhancing or restoring GC sensitivity can improve outcome. To first determine how GCs kill B-ALL cells, we first measured the transcriptional response of sensitive B-ALL samples to dexamethasone (dex). In addition to apoptotic genes (BIM, BCL2), and metabolic genes (TXNIP) identified in other studies that contribute to cell death, we also found broad regulation of B cell development genes, including key checkpoints (ITGA4, IL7R, and BCL6). This suggested that high levels of GCs push arrested B-ALL cells through development, resulting in cell death. To validate these results, and to identify cellular pathways that modulate GC cytotoxicity, we used a next-generation shRNA screen to knock down every protein-coding gene in the genome. The screen identified 265 genes that significantly modulate GC sensitivity. In addition to validating the importance lymphoid development genes, the screen revealed which cofactors and chromatin modifiers collaborate with GR to orchestrate cell death gene programs. Further we were able to map critical signaling pathways with high resolution, including the pro-survival B cell receptor pathway. Inhibition of PI3Kδ at the apex of this pathway potentiated the response of GC-regulated genes to dex, and synnergized with dex to induce cell death in even the most refractory B-ALL tissue. These results indicate a previously unrecognized for GCs in B cell development that can be exploited to improve both the potency and treatment of lymhoid disease.
Citation Format: Miles Pufall, Karina Kruth, Sarah K. Tasian. Genome-wide screen reveals a role for glucocorticoids in B cell development that can be exploited to improve treatment of B cell acute lymphoblastic leukemia. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2438.
Abstract 2448: Suppression of MYCN-driven neuroblastoma malignant phenotype by telomerase-targeted tumor suppressor p53 transactivation
Authors: Tanimoto Terutaka , Tazawa Hiroshi , Noso Hiroshi , Oyama Takanori , Urata Yasuo , Kagawa Shunsuke , Noda Takuo , Fujiwara Toshiyoshi 
Published: July 2016

Abstract
Background: Neuroblastoma (NB) is a primary malignant tumor in the peripheral sympathetic nervous system. High-risk group of NB has an unfavorable clinical course, even after treatment with current chemotherapy regimens and aggressive surgical resection. Therefore, a novel therapeutic strategy is needed for the treatment of high-risk group of NB. Recent accumulating evidences in whole-genome sequencing analysis have shown that human telomerase reverse transcriptase (hTERT) gene rearrangement and MYCN gene amplification are predictive biomarkers for the high-risk group of NB, in which massive transcriptional activation of hTERT mRNA was frequently observed. We recently developed two types of hTERT-driven oncolytic adenoviruses, OBP-301 and OBP-702, in which the hTERT promoter drives the expression of the viral E1A and E1B genes for tumor-specific virus replication, and OBP-702 further expresses tumor suppressor p53 protein. In this study, we investigated whether OBP-301 and OBP-702 inhibit cell viability and MYCN protein expression in human NB cells with different MYCN status.
Methods: We used 3 human NB cell lines with or without MYCN amplification, including IMR-32 (MYCN-amplified), LA-N-5 (MYCN-amplified), SK-N-SH (MYCN-not amplified). The antitumor effects of OBP-301, OBP-702, and Ad-p53, a replication-defective adenovirus expressing p53 gene, were evaluated using XTT assay. Virus-induced apoptosis and MYCN suppression were analyzed by Western blot analysis.
Results: OBP-301, OBP-702, and Ad-p53 suppressed the viability of all 3 NB cell lines, whereas OBP-702 showed the most profound anti-tumor effect especially in MYCN-amplified NB cells. OBP-702 induced higher p53 expression than Ad-p53, resulting in the p53-mediated apoptotic cell death. Although MYCN expression in NB cells with MYCN amplification was downregulated after infection with all types of adenoviruses, the inhibitory effect of OBP-702 was the strongest among these adenoviruses.
Conclusions: These results suggest that a hTERT-driven oncolytic adenovirus OBP-702 is a promising antitumor agent to induce profound apoptotic cell death through p53 transactivation and MYCN suppression in human NB cells with or without MYCN amplification. In vivo experiments are under way to investigate the antitumor effect of OBP-702 against xenograft NB tumors.
Citation Format: Terutaka Tanimoto, Hiroshi Tazawa, Hiroshi Noso, Takanori Oyama, Yasuo Urata, Shunsuke Kagawa, Takuo Noda, Toshiyoshi Fujiwara. Suppression of MYCN-driven neuroblastoma malignant phenotype by telomerase-targeted tumor suppressor p53 transactivation. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2448.