bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 2367: Identification of p-AKT as a PD marker for MER kinase in human G361 cells
Authors: Chen Yaoyu
Published: August 2018

Abnormalities in receptor tyrosine kinases (RTKs) have been shown to be involved in a wide range of important biological activities in cancer, including cell proliferation, differentiation and drug resistance. The TAM family of RTKs includes three family members: TYRO3, AXL, and MER. Binding of ligands to the these receptors was reported to lead to activation of the TAM kinases, as well as PI3K/AKT, RAS/RAF/MAPK and JAK/STAT signaling pathways in human cancer cells. Among these three TAM kinases, the MER signaling pathway represents an attractive target for the treatment of human cancers. MER phosphorylation is dependent on the ligand GAS6, however, ligand activated phospho-MER is often not stable and is very difficult to detect without pervanadate pretreatment in human cancer cells and this has been a hurdle for developing a selective MER kinase inhibitor. Therefore, it is important to identify a specific pharmacodynamic marker to monitor MER kinase activity in human cancer cells. Here, we report the development of a phospho-AKT assay for characterization of MER kinase inhibitors in human G361 cells. We profiled the expression of MER among multiple human cancer cells and demonstrated that MER and TYRO3, but not AXL show high levels of protein expression in human G361 melanoma cells. In G361 cells, phospho-AKT is induced by GAS6 treatment and the induction of phospho-AKT can be reversed by AXL/MER tool compounds. To determine the role MER and TYRO3 play in the activation of phospho-AKT, either MER or TYRO3 was selectively depleted by siRNA knockdown. We demonstrate that GAS6 induced phospho-AKT is only dependent on MER kinase, but not TYRO3 in human G361 melanoma cells. In addition, using phospho-AKT as readout, a high-throughput cell-based assay was established in the G361 human melanoma cells for evaluation of compound potency in inhibiting MER pathway activation. Further, we observed a correlation in compound potency between inhibition of phospho-AKT in G-361 cells and phospho-MER in MER-overexpressing BAF3 cells. In summary, we have demonstrated that GAS6 induced phospho-AKT can be a potential pharmacodynamic marker for inhibition of MER kinase and have successfully developed a cell-based functional assay for screening small molecule inhibitors of MER kinase for potential therapeutic utility in treating GAS6/MER-deregulated human cancers.

Citation Format: Yaoyu Chen. Identification of p-AKT as a PD marker for MER kinase in human G361 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 2367.
Abstract 2377: Design, synthesis, and characterization of 4-aminopyrazole quinazolines as potent inhibitors of G protein-coupled receptor kinase GRK6 for the potential treatment of multiple myeloma
Authors: Uehling David , Joseph Babu , Griffin Carly , Subramaniam Ratheesh , Abibi Ayome , Marcellus Richard , Prakesch Michael , Poda Gennadiy , Isaac Methvin , Leung-Hagesteijn Chungyee , Tiedemann Rodger , Al-awar Rima
Published: August 2018

Multiple myeloma (MM) is one of the most common hematological malignancies, but current therapeutic options are limited to high-dose chemotherapy or high-risk stem-cell transplantation. In a kinome-wide RNAi study by Tiedemann and colleagues (2010), the G-protein coupled receptor kinase GRK6 was identified as a critical kinase required for survival of MM cells. This study also suggests that MM cells, but not other cell types, are dependent on GRK6; and that gene silencing by shRNA or siRNA of GRK6, but not other members of the GRK family, results in decreased survival. Through gene silencing techniques, we determined that a functional GRK6 kinase domain is required for survival of MM cells. These findings helped validate that the kinase domain of GRK6 is a promising target for MM, and therefore encouraged us to embark on an effort to identify potent small molecule kinase inhibitors of GRK6. Toward that end, by screening a focused kinase-directed library of small molecule inhibitors, compounds with moderate potency against GRK6 in biochemical assays were identified. Through this exercise, we discovered that two structurally distinct aminopyrazoles AZ-960 and ASC-082 had modest inhibition of GRK6. By combining structural features of these hits and further optimization we identified the quinazoline analogue OICR9945, a potent GRK6 inhibitor with good selectivity against a panel of diverse kinases and anti-proliferative activity against MM cell lines. Herein, we describe the design, synthesis and early pharmacological characterization of OICR9945 along with structure activity relationships (SAR) of this series against GRK6 and other kinases.

Citation Format: David Uehling, Babu Joseph, Carly Griffin, Ratheesh Subramaniam, Ayome Abibi, Richard Marcellus, Michael Prakesch, Gennadiy Poda, Methvin Isaac, Chungyee Leung-Hagesteijn, Rodger Tiedemann, Rima Al-awar. Design, synthesis, and characterization of 4-aminopyrazole quinazolines as potent inhibitors of G protein-coupled receptor kinase GRK6 for the potential treatment of multiple myeloma [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 2377.
Abstract 238: Interaction analysis between germline susceptibility loci and somatic alterations in lung cancer
Authors: Wang Yuzhuo , Wang Cheng , Zhu Meng , Jin Guangfu , Shen Hongbing
Published: August 2018

Emerging evidence indicates that germline variations may interact with somatic events in carcinogenesis. However, the germline-somatic interaction in lung cancer remains largely unknown. In the present study, we investigated whether lung cancer driver genes (CDGs) were more likely to locate within cancer susceptibility regions. Additional pathway enrichment analysis was performed to identify common pathways underlying CDGs and cancer susceptibility genes (CSGs). Next, we analyzed the associations between lung cancer risk SNPs and somatic alterations, including mutations and copy number alterations, in the level of genes, pathways, and overall burden of alterations. Enrichment analysis showed that lung CDGs are more likely to locate within cancer susceptibility regions (P = 8.40×10-3). Both of lung CSGs and CDGs showed significant enrichment in pathways such as cell cycle and p53 signaling pathway. Gene-based analysis showed that rs36600 (22q12.2) was associated with somatic mutations within ARID1A (OR = 2.45, 95%CI: 1.47-4.08, P = 5.78×10-4). Pathway-based analysis identified rs2395185 and rs3817963 at 6p22.1 were associated with somatic truncation mutations in cell cycle pathway (OR = 1.56, P = 3.61×10-4 for rs2395185; OR = 1.58, P = 4.15×10-4 for rs3817963), and rs3817963 was also associated with somatic truncation mutations in MAPK signaling pathway (OR = 1.54, P = 8.58×10-4). Further analysis associated rs2395185 at 6p22.1 (HLA class II genes) with increased APOBEC3A expression (P = 9.50×10-3) and elevated APOBEC mutagenesis (P = 3.58×10-3). These results provide evidence for the germline-somatic interactions on lung tumorigenesis. This can help to uncover the molecular mechanisms by which risk SNPs influence lung cancer risk.

Citation Format: Yuzhuo Wang, Cheng Wang, Meng Zhu, Guangfu Jin, Hongbing Shen. Interaction analysis between germline susceptibility loci and somatic alterations 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 238.
Abstract 2414: Interrogating cellular metabolism reveals mTORC2 as a new biomarker to stratify epidermal growth factor receptor-mutant non-small cell lung cancer
Authors: Chiang Chun-Te , Ung Nolan , Demetriou Alexandra N. , Chiu Chi-Li , Choudhury Niha , Arnesano Cosimo , Fraser Scott E. , Agus David B. , Matasci Naim , Ruderman Dan L. , Mumenthaler Shannon M.
Published: August 2018

Most non-small cell lung cancer (NSCLC) patients with epidermal growth factor (EGFR) mutations initially respond to EGFR tyrosine-kinase inhibitors (TKIs), but these inhibitors are only effective for approximately one year, thus limiting the benefits to patients' survival. Stratification of patients with EGFR-mutant NSCLC would help physicians personalize and optimize patient treatment plans. To this end, we hypothesized that factors residing in the tumor microenvironment play a pivotal role in the evolutionary dynamics of therapeutic response to anti-EGFR therapies. We used the Operetta® High Content Imaging System to track cell dynamics over time under different microenvironmental stresses, and we found that the growth of TKI-resistant cells is more sensitive to glucose starvation than TKI-sensitive cells. To further interrogate cellular metabolism in TKI-sensitive and resistant cells, we utilized both seahorse metabolic assays and fluorescence lifetime imaging microscopy to monitor the changes in glycolysis and oxidative phosphorylation of living cells. We found TKI-resistant cells have higher glycolysis and lower oxidative phosphorylation rates compared to TKI-sensitive cells. Such metabolic reprogramming rendered TKI-resistant cells with lower metabolic plasticity to cope with metabolic stress. Using both genetic and pharmacologic approaches, we then demonstrated that mTORC2 activation contributes to the different metabolic phenotypes between TKI-sensitive and resistant cells. Furthermore, gene set enrichment analysis showed that the oxidative phosphorylation gene set is significantly enriched in patients with low mTORC2 activation, and the glycolysis gene set is upregulated in patients with high mTORC2 activation, which is correlated with shorter progression-free and overall survival time in patients. Overall, these data suggest that TKI-resistant cells use and require distinct metabolic programs that can be employed to stratify EGFR-mutant NSCLC patients for treatment with EGFR-TKIs.

Citation Format: Chun-Te Chiang, Nolan Ung, Alexandra N. Demetriou, Chi-Li Chiu, Niha Choudhury, Cosimo Arnesano, Scott E. Fraser, David B. Agus, Naim Matasci, Dan L. Ruderman, Shannon M. Mumenthaler. Interrogating cellular metabolism reveals mTORC2 as a new biomarker to stratify epidermal growth factor receptor-mutant non-small cell 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 2414.
Abstract 2421: SOD1 is required for tumor maintenance in a genetically engineered KRAS/TP53 non-small cell lung cancer mouse model
Authors: Wang Xiaowen , Wong Justin , Remmen Holly Van , Guo Jessie Yanxiang , White Eileen , Zheng X. F. Steven
Published: August 2018

Lung cancer is the second most common cancer and the primary cause of cancer-related mortality globally. Over half a million people are estimated living with lung and bronchus cancer with a 5-year survival rate of 18%. Identifying and studying new drug targets are important for improving lung cancer patient survival. 80% to 85% of lung cancers are Non-small cell lung cancer (NSCLC). Knocking down and small molecule inhibition of Superoxide dismutase 1 (SOD1) has been shown to be cytotoxic to cultured NSCLC cells and mouse tumors, suggesting that SOD1 is important for NSCLC survival, thus presenting a promising therapeutic strategy. SOD1 rapidly converts superoxide anion to hydrogen peroxide. It is a critical component of the cellular antioxidant defense system. In addition, our laboratory has recently demonstrated that SOD1 has a novel function as a transcription factor that regulates oxidative stress response genes. Currently, there are no selective SOD1 inhibitors available to study physiological functions of SOD1. In our study, we show that genetically knockout SOD1 resulted in reduced tumor burden in lung cancer mouse model. Using mouse tumor-derived primary cancer cells, we further show that SOD1 is critical for NSCLC cell proliferation and survival. This study reveals novel functions of SOD1 that are of biological and translational significance, and provide further support for SOD1 as a promising therapeutic target for NSCLC.

Citation Format: Xiaowen Wang, Justin Wong, Holly Van Remmen, Jessie Yanxiang Guo, Eileen White, X. F. Steven Zheng. SOD1 is required for tumor maintenance in a genetically engineered KRAS/TP53 non-small cell lung cancer mouse model [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 2421.
Abstract 244: Pathway analysis of OncoArray data identifies biological pathways involved in lung cancer development
Authors: Wang Zhihui , Zhang Ruyang , Su Li , Hung Rayjean , Amos Christopher , Christiani David C.
Published: August 2018

Background:Genome-wide association studies (GWAS) have identified susceptible loci associated with lung cancer development. However, these variants only account for a small proportion of lung cancer heritability. With the aim to identify the missing heritability, we propose to conduct pathway analysis to test the joint effects of rare and common variants using the OncoArray data. By grouping SNPs into genes and pathways, we may shed light into the underlying mechanisms for lung cancer development and identify novel candidate genes and pathways.Methods:We applied sequence kernel association test (SKAT) to the OncoArray data of the Transdisciplinary Research of Cancer in lung of the International Lung Cancer Consortium (TRICL-ILCCO) that includes 34,432 individuals (19,028 cases and 15,404 controls) across over twenty lung cancer studies. A total of 403 KEGG and Biocarta pathways containing 5,555 genes and 58,717 SNPs were included in the study. As a score-based variance-component test, SKAT calculated p values for each pathway set by fitting the null model containing only age, gender, smoking, and first three PCAs. Results:KEGG neuroactive ligand receptor interaction (p=1.18×10-4, FDR=0.0285) and KEGG pancreatic cancer pathways (p=1.41×10-4, FDR=0.0285) were significantly associated with lung cancer. Gene-based analyses found that the most significant genes on the KEGG neuroactive ligand receptor interaction pathway to be CHRNA5 (p=2.33×10-8, FDR=0.0003), CHRNA3 (p=2.85×10-7, FDR=0.0019), and CHRNB4 (p=7.49×10-7, FDR=0.0034), while the most significant genes for KEGG pancreatic cancer pathway to be BRCA2 (p=2.23×10-5, FDR=0.0505). Stratified analyses highlighted five pathways (KEGG intestinal immune network for IGA production, KEGG leishmania infection, KEGG bladder cancer, KEGG pancreatic cancer, and KEGG axon guidance) for squamous cell carcinoma and one pathway (Biocarta ACH pathway) for adenocarcinoma with FWER<0.05. Noteworthy, the most significant gene on ACH pathway for adenocarcinoma was TERT gene, whereas the top two significant pathways for squamous carcinoma shared the most significant HLA-DQA1 gene, along with 11 other HLA genes at 6p21.Conclusion:The results suggest that the underlying pathways differ by cancer cell types and further research should be conducted to investigate the effects of immune pathways and HLA genes on squamous cell carcinoma etiology.

Citation Format: Zhihui Wang, Ruyang Zhang, Li Su, Rayjean Hung, Christopher Amos, David C. Christiani. Pathway analysis of OncoArray data identifies biological pathways involved in lung cancer development [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 244.
Abstract 2474: Identification of lncRNAs involved in regulation of chromosome instability-associated genes in a prostate cancer model
Authors: Manriquez Rogelio Montiel , Canon Cristian Gabriel Oliverio Arriaga , Soberanis Fernanda Cisneros , César Cortés Carlo , Velazquez Inti Alberto De La Rosa , Montalvo Luis Alonso Herrera
Published: August 2018

In this study we aim to identify new lncRNAs, using RNA-seq data, and study whether those transcripts could be involved in chromosomal instability in prostate cancer and propose new possible RNA-based biomarkers. Using RNA-seq data from two prostate cell lines, neoplastic and non-neoplastic, we have identified a new lncRNA adjacent to CEP55, a gene associated with chromosomal instability. This lncRNA, which we have named lncRNA-CEP55, is 1.6 kb long and it is downregulated in the neoplastic cell line; this is also seen in the adjacent coding gene, CEP55, where the expression decreases in the neoplastic line, suggesting an important role of this transcript in carcinogenesis. This new lncRNA could be regulating CEP55 expression in these cell lines. Changes in expression of CEP55 have been associated to chromosomal instability and cancer development in colon cancer cell lines. Another lncRNA with differential expression in both cell lines has been identified, lncRNA-RFC4. This lncRNA has been reported before; it is an annotated gene in the human genome GRCh38/hg38, but it has not been studied in cancer. This lncRNA is highly expressed in the neoplastic cell line whereas its expression is very low in the non-neoplastic cell line. This lncRNA is 4.3 kb away from RFC4 (Replication Factor C Subunit 4), a protein coding gene related to mismatch repair and DNA double-strand break repair, which has been associated with chromosomal instability. lncRNA-RFC4 could be playing an important role in the cis regulation of RFC4 gene. lncRNA-CEP55 and lncRNA-RFC4 are important targets of study because of their differential expression in prostate cell lines (neoplastic and non-neoplastic). These lncRNAs could be playing an essential role in regulating the expression of the adjacent genes related to chromosomal instability, a enabling characteristic that facilitates the acquisition of the hallmarks of cancer.

Citation Format: Rogelio Montiel Manriquez, Cristian Gabriel Oliverio Arriaga Canon, Fernanda Cisneros Soberanis, Carlo César Cortés, Inti Alberto De La Rosa Velazquez, Luis Alonso Herrera Montalvo. Identification of lncRNAs involved in regulation of chromosome instability-associated genes in a prostate cancer model [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 2474.
Abstract 2482: RanBP17 retards the epithelial-mesenchymal transition (EMT) and malignant progression of glioblastoma cells by regulating the exportation of beta-catenin from cell nucleus
Authors: Wang Yi , Guo Penyi , Xie Xiaozai , Zhang Sina , Yu Haitao , Wu Lijun , Chen Ziyan , Chen Gang
Published: August 2018

Background: Glioblastoma multiforme (GBM) is the most common and lethal primary human brain tumor and exhibits multiple molecular aberrations. In this study, we attempted to explore the role of a nuclear transport receptor RanBP17 in carcinogenesis and its underlying mechanisms in GBM.

Methods: The relevant information retrieved from the Human Integrated Protein Expression Database (HIPED), TCGA, and Rembrandt was analyzed to evaluate and compare RanBP17 expression in various tissues and cancer types. Next U87 and U251 were used to investigate the effects of RPS15A on epithelial-mesenchymal transition (EMT) and malignant behaviors of glioma cells. Further, RPS15A-associated signaling pathways were screened based on the data from the Kyoto Encyclopedia of Genes and Genomes (KEGG) database and verified by using RT-PCR and Western blot (WB) assays.

Results: RanBP17 was highly expressed in normal brain tissue, and loss or downregulation of RanBP17 was observed in GBM tissue (83/105, 79.05%) and associated with worse survival of patients. Overexpression of RanBP17 suppressed proliferation, migration and invasion of GBM cells in vitro and remarkably inhibited tumor growth in vivo. In addition, RanBP17 silencing promoted EMT of glioma cells via activating the expression of transcriptional factor Snail. Further experiments confirmed that RanBP17 overexpression promoted the export of β-catenin from cell nuclei and retarded wnt/β-catenin signaling. Conversely, knockdown of RanBP17 gene resulted in accumulation of β-catenin in glioblastoma cell nuclei, which, in turn, promoted expression of EMT-related proteins and malignant progression of glioblastoma by combining other transcript genes.

Conclusions: RanBP17 expression is significantly lower in GBM compared to normal brain tissue. Silencing RanBP17 accelerates the EMT process and malignant progression of glioblastoma due to the suppressed export of β-catenin from glioblastoma cell nuclei and the resulting inhibition of wnt/β-catenin signaling. Therefore, loss or downregulation of RanBP17 can be considered a negative prognostic factor for survival of GBM patients.

Citation Format: Yi Wang, Penyi Guo, Xiaozai Xie, Sina Zhang, Haitao Yu, Lijun Wu, Ziyan Chen, Gang Chen. RanBP17 retards the epithelial-mesenchymal transition (EMT) and malignant progression of glioblastoma cells by regulating the exportation of beta-catenin from cell nucleus [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 2482.
Abstract 2494: A novel tool for monitoring endogenous progesterone receptor expression by mCherry using CRISPR-Cas9 genome editing technique
Authors: Li Yiyang , Meng Xiangbing , Wen Kuo-kuang , Wu Meng , Dupuy Adam , Leslie Kimberly , Yang Shujie
Published: August 2018

Expression of progesterone receptor (PR) is a favorable prognostic marker for multiple solid tumors. However, PR expression is reduced or lost in malignant tumors which hinders response to progesterone therapy. Thus, monitoring and restoring functional PR expression is of utmost importance to sensitize progesterone therapy in endometrial cancer. We developed a stable cell line expressing the endogenous PR gene tagged a reporter gene (Hygromycin and mCherry) with CRISPR/Cas9-mediated genome editing. This allows efficient monitoring of PR expression in its native epigenetic landscape. The reporter gene expression faithfully reflects and amplifies PR expression following treatment with histone deacetylase inhibitor, romidepsin. This reporter gene transfected cells were successfully used to screen the FDA-approved 1018 library by high throughput screening in searching of potential novel drugs that increase PR expression. This strategy provides an efficient drug screening tool that can be used to screen novel PR inducers in multiple cancer cell lines.

Citation Format: Yiyang Li, Xiangbing Meng, Kuo-kuang Wen, Meng Wu, Adam Dupuy, Kimberly Leslie, Shujie Yang. A novel tool for monitoring endogenous progesterone receptor expression by mCherry using CRISPR-Cas9 genome editing technique [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 2494.
Abstract 2503: Rational design of small-molecule immune checkpoints' inhibitors
Authors: Barakat Khaled
Published: August 2018

Blocking the PD-1/PD-L1 and CTLA-4 pathways recently emerged as a ‘game changer' in cancer immunotherapy, leading to the selection of monoclonal-antibodies (MABs) targeting PD-1 as ‘drug of the year' for 2013. Although these antibodies restored exhausted T cells' function to recognize and kill tumor cells, these MABs have numerous disadvantages. These include their very high cost and very severe side effects. Our team has been focused on designing small molecule inhibitors for this pathway. Compared to available MAB therapies, our small molecules may offer a more affordable, more easily administered and better controlled treatment for a variety of cancers. Here, we demonstrate our efforts toward this goal and summarize our data on our promising compounds targeting the PD-1/PD-L1 and CTLA-4 pathways.

Citation Format: Khaled Barakat. Rational design of small-molecule immune checkpoints' inhibitors [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 2503.
Abstract 2509: Blockage of angiotensin II type 1 receptor (AGTR1) inhibits epithelial-mesenchymal transition (EMT) and tumor growth in breast cancer
Authors: Kim Ji Young , Oh Eunhye , Kim Yoon-Jae , Sung Daeil , Cho Tae-Min , Jang Seojin , Seo Jae Hong
Published: August 2018

The angiotensin II type I receptor (AGTR1) has been implicated in diverse aspects of human disease, from the regulation of blood pressure and cardiovascular homeostasis. A recent study has reported pathogenic overexpression of the angiotensin II type 1 receptor (AGTR1) in breast cancers. We sought to investigate the effect of losartan, an angiotensin II receptor blocker on cell proliferation, epithelial-mesenchymal transition (EMT), angiogenesis and tumor growth in breast cancer. Overexpression of AGTR1 was associated with accelerated cell proliferation, concomitant with increased expression of survival factors including poly(ADP-ribose) polymerase (PARP) and X-linked inhibitor of apoptosis (XIAP), as well as extracellular signal-regulated kinase (ERK) activation. AGTR1-overexpressing MCF7 cells were more aggressive than their parent line, with significantly increased activity in migration and invasion assays. These observations were associated with changes in EMT markers, including reduced E-cadherin expression and increased p-Smad3, Smad4 and Snail levels. Treatment with the AGTR1 antagonist losartan attenuated these effects in vitro. To confirm the physiological relevance of our in vitro observations, we examined the effect of losartan on tumor growth using a mammary fat pad xenograft model with the AGTR1-overexpressing cells. Losartan administration resulted in a significant reduction in tumor growth and a significant decrease in the number of Ki-67-positive cells in the AGTR1-overexpressing xenograft tumors. Losartan administration notably upregulated E-cadherin and suppressed vimentin expression. Furthermore, microvessel density analysis revealed that the number of CD31-positive microvessels in both the peritumoral and intratumoral areas was significantly decreased in the losartan-treated groups. Our findings support the notion that AGTR1 is a potentially useful diagnostic marker and its inhibition may provide an effective therapeutic strategy for breast cancer treatment.

Citation Format: Ji Young Kim, Eunhye Oh, Yoon-Jae Kim, Daeil Sung, Tae-Min Cho, Seojin Jang, Jae Hong Seo. Blockage of angiotensin II type 1 receptor (AGTR1) inhibits epithelial-mesenchymal transition (EMT) and tumor growth in 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 2509.
Abstract 2510: Clinicopathologic significance of fibroblast growth factor 2 type IIIb and type IIIc in gastric cancer
Authors: Kuroda Kenji , Yashiro Masakazu , Masuda Go , Miki Yuichiro , Okuno Tomohisa , Togano Shingo , Toyokawa Takahiro , Tanaka Hiroaki , Muguruma Kazuya , Hirakawa Kosei , Ohira Masaichi
Published: August 2018

[Background]Fibroblast Growth Factor Receptor 2(FGFR2) amplification occuers flequently in undifferentiated gastric cancer(GC), and accounts for 3-10% of primay GC. FGFR2 shows two isoforms, IIIb-type expressed in epithelial cells, and IIIc-type expressed in mesenchymal cells. The aim of this study is evaluating clinicopathological significance of FGFR2-IIIb and IIIc expression on GC cells.

[Method]562 patients who had undergone GC surgery were retrospectively examined. Immunohistochemistry of resected specimen was used to investigate the expression of FGFR2-IIIb and IIIc.

[Result]FGFR2-IIIb and FGFR2-IIIc were positive in 28 cases (4.9%) and 4 cases (0.7%) of 562 gastric cancers. All of FGFR2-IIIc positive tumors were also positive for FGFR2-IIIb in a same tumor, but both were not positive in same cells. 5-year overall survival rate of FGFR2 positive group is significantly poorer (p=0.0011, log-lank) than that of FGFR2 negative. Moreover, the prognosis of FGFR2-IIIc positive group was significantly poorer (p=0.003, log-lank) than that of FGFR2-IIIb positive group. In univariate analysis, the overall survival was significantly correlated to FGFR2-IIIb positive, FGFR2-IIIc positive, invasion depth, macroscopic type, histological type, lymph node metastasis, peritoneal dissemination, lymphatic invasion, and cytology. In multivariate analysis, FGFR2IIIc was significantly correlated to overall survival (p=0.045)

[Conclusion] The expression of FGFR2IIIc and/or FGFR2IIIb was observed in 5% of gastric cancer. FGFR2 amplification is associated with poor overall survival. As a result, treatment targeting FGFR2 amplification has the potential to provide clinical benefit for FGFR2 positive GC.

Citation Format: Kenji Kuroda, Masakazu Yashiro, Go Masuda, Yuichiro Miki, Tomohisa Okuno, Shingo Togano, Takahiro Toyokawa, Hiroaki Tanaka, Kazuya Muguruma, Kosei Hirakawa, Masaichi Ohira. Clinicopathologic significance of fibroblast growth factor 2 type IIIb and type IIIc in gastric 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 2510.
Abstract 2524: A new mTOR-independent effect of rapamycin: Transcriptional regulation of TRIB3
Authors: Stefanovska Bojana , Vicier Cécile , Scott Véronique , Meurice Guillaume , André Fabrice , Fromigué Olivia
Published: August 2018

Background: Mechanistic Target of Rapamycin (mTOR), a key component of the PI3K/Akt signaling pathway, coordinates various cellular processes such as metabolism, growth, cell proliferation and cell cycle progression. Dysregulations affecting mTOR frequently occur in cancer, and mTOR inhibitors/rapalogs are used as monotherapy or a part of combination therapy in breast or kidney metastatic cancer. Despite this, response rate is modest. Several mechanisms of resistance have been reported, but do not fully characterize insensitive tumor cells. Purpose: This study investigated new target genes of rapamycin/rapalogs. Methods: Expression levels of target genes were evaluated in a panel of cancer cell lines by transcriptomic analyses, real-time qPCR and western blot. Transcriptional regulation was investigated by in silico analyses of the promoter region, gene reporter assays using site-directed mutagenesis, and ChIP. Stably silenced cell lines were established by lentiviral transduction of shRNA sequences. Results: We identified one gene: TRIB3 (Tribbles Pseudokinase 3), whose expression is downregulated in the presence of rapamycin in a panel of cancer cell lines and in PBMCs isolated from cancer patients. This gene encodes for a pseudokinase involved in a glucose-induced insulin resistance in Type 2 Diabetes by inhibiting the activation of Akt1/2. We observed that silencing mTOR did not mimic rapamycin downregulation of TRIB3, suggesting an mTOR-independent effect of rapamycin. We identified a binding site for the transcriptional repressor GCF2/LRRFIP1 in the promoter region of TRIB3, and confirmed that the presence and the binding of GCF2 to TRIB3 promoter are required for TRIB3 downregulation by rapamycin. Finally, we identified FKBP3 (FK506-Binding Protein 3), a protein that can bind rapamycin with high affinity, as a GCF2 partner, confirming the direct effect of rapamycin on TRIB3 promoter. Conclusions: Taken together, our investigations identified a novel transcriptional target gene of rapamycin: TRIB3. We also characterized the molecular mechanism of regulation by rapamycin through a FKBP3/GCF2-dependent repression of TRIB3 promoter activity, and independently of mTOR signaling. Such variations in TRIB3 expression level in cancer cells could be linked to rapamycin sensitivity, and may represent a valuable therapeutic target.

Citation Format: Bojana Stefanovska, Cécile Vicier, Véronique Scott, Guillaume Meurice, Fabrice André, Olivia Fromigué. A new mTOR-independent effect of rapamycin: Transcriptional regulation of TRIB3 [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 2524.
Abstract 2537: Regulation of LMO2 oncogene expression in high-risk B-cell acute lymphoblastic leukemia
Authors: Ding Yali , Payne Jonathon L. , Kane Shriya , Dovat Elanora , Soliman Mario , Song Chunhua , Dovat Sinisa
Published: August 2018

LIM domain only protein 2 (LMO2) is an oncogene that is overexpressed in a subset of B-cell acute lymphoblastic leukemia (B-ALL). The mechanisms that regulate LMO2 expression in B-ALL are still unknown. Here, we show that transcription of LMO2 in B-ALL is regulated by Ikaros, a tumor suppressor protein, which is encoded by the IKZF1 gene, and whose deletion is associated with development of high-risk B-ALL. The use of global chromatin immunoprecipitation coupled with the next-generation sequencing (ChIP-seq) studies in primary human B-ALL cells and in cell lines revealed a strong Ikaros occupancy at the promoter of the LMO2 gene. Ikaros binding to the LMO2 promoter was confirmed by quantitative chromatin immunoprecipitation (qChIP). We tested the role of Ikaros in regulating LMO2 transcription in B-ALL using gain-of-function and loss-of-function experiments. A luciferase reporter assay with the LMO2 promoter showed that Ikaros directly represses LMO2 transcription. Overexpression of Ikaros in B-ALL via retroviral transduction was associated with strongly reduced expression of LMO2. Furthermore, Ikaros knock-down with shRNA, resulted in increased transcription of LMO2 in B-ALL cells. These results suggest that Ikaros represses transcription of LMO2 in B-ALL. Since Ikaros' function in B-ALL is negatively regulated by pro-oncogenic Casein Kinase II (CK2), we tested whether CK2 inhibition affects Ikaros-mediated repression of LMO2. Both molecular inhibition with shRNA, and pharmacological inhibition of CK2 with a specific CK2 inhibitor, CX-4945, resulted in reduced expression of LMO2. Inhibition of CK2 was also associated with increased Ikaros occupancy at the LMO2 promoter. In high-risk B-ALL that have deletion of a single copy of the IKZF1 gene, Ikaros does not bind to the LMO2 promoter. Treatment of primary B-ALL cells that have IKZF1 haploinsufficiency restores Ikaros binding to the LMO2 promoter and results in reduced LMO2 expression. In conclusion, our data demonstrate that Ikaros and CK2 regulate transcription and overall expression of the LMO2 oncogene in B-ALL. Our results identify a novel mechanism of therapeutic action of CK2 inhibitors in high-risk B-ALL—repression of LMO2 expression via restoration of Ikaros' tumor suppressor function.

Citation Format: Yali Ding, Jonathon L. Payne, Shriya Kane, Elanora Dovat, Mario Soliman, Chunhua Song, Sinisa Dovat. Regulation of LMO2 oncogene expression in high-risk B-cell acute lymphoblastic leukemia [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 2537.
Abstract 2547: A potential new autologous mast cell cancer immunotherapy
Authors: Plotkin Jesse D. , Elias Michael G. , Daniels-Wells Tracy R. , Dellinger Anthony , Penichet Manuel L. , Kepley Christopher L.
Published: August 2018

Mast cells (MC) are important immune cells that reside in tissue and are most widely recognized for their role as mediators of Type I hypersensitivity reactions (allergies). In certain cancers, such as breast cancer, the presence of MC in the tumor microenvironment has been associated with favorable prognosis, which may be due to their ability to release, through activation of the high affinity IgE receptor FcεRI, anti-tumor mediators such as tumor necrosis factor alpha (TNF-α) and granulocyte-macrophage colony-stimulating factor (GM-CSF). Thus, developing approaches to target autologous MC to tumor antigens is a potential new form of cancer immunotherapy. However, this concept has not been realized given that MC reside in tissue; thus, efficient removal, expansion ex vivo, and targeting to tumor sites has not yet been feasible. Previous attempts to generate MC from human progenitor cells have yielded cells that are often immature and not optimally functional. We report here, for the first time, the generation of functional human MC from adipose tissue in numbers sufficient for clinical applications. The adipose derived MC (ADMC) are phenotypically similar to connective tissue MC as evidenced through their expression of tryptase, chymase, c-kit, and FcεRI. The ADMC release several anti-tumor mediators through FcεRI activation. The ADMC, sensitized with an anti-HER2/neu IgE with human constant regions, bound to and were activated by HER2/neu-positive human breast cancer cells (SK-BR-3). ADMC sensitized in this way were observed to induce apoptosis in breast cancer cells when co-cultured. Importantly, breast cancer cell apoptosis was also observed after addition of media containing mediators released from activated ADMC. In conclusion, we present a novel method for the production of functional human MC from adipose tissue and demonstrate that these cells can be directed to target and eliminate breast cancer cells. It may now be possible to use them in conjunction with IgE antibodies targeting cancer cells for autologous mast cell cancer immunotherapy (AMCIT) as a new way to treat solid tumors such as those overexpressing HER2/neu for which new therapies are urgently need.

Citation Format: Jesse D. Plotkin, Michael G. Elias, Tracy R. Daniels-Wells, Anthony Dellinger, Manuel L. Penichet, Christopher L. Kepley. A potential new autologous mast cell cancer immunotherapy [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 2547.
Abstract 2578: Expression of epiregulin/amphiregulin associates with prognosis in recurrent/metastatic head and neck cancer treated with cetuximab
Authors: Kogashiwa Yasunao , Inoue Hitoshi , Kuba Kiyomi , Yasuda Masanori , Nakahira Mitsuhiko , Sugasawa Masashi
Published: August 2018

Objectives: The anti-EGFR antibody cetuximab, combined with chemotherapy, is the standard therapy for recurrent/metastatic (R/M) head and neck squamous cell carcinoma (HNSCC). However, the response rate and survival benefit are limited. The purpose of this study was to investigate the expression of the epidermal growth factor receptor ligands epiregulin (EREG) and amphiregulin (AREG), as predictive prognostic markers for the efficacy of cetuximab combined with chemotherapy in R/M HNSCC.

Materials and methods: We conducted a retrospective analysis of 37 patients diagnosed with R/M HNSCC. Tumor samples from biopsy specimens or surgical specimens were analyzed for EREG and AREG mRNA gene expression, and clinical outcomes evaluated. Survival rates were estimated by Kaplan-Meier analysis. Cox proportional hazard regression was used to test the potential association between ligand expression, overall survival (OS), and progression free survival (PFS).

Results: Values of EREG ≤ 15.87 and AREG ≤ 11.80, determined by receiver operating characteristic (ROC) curve analysis, were associated with significantly longer OS (p=0.03 and p=0.01, respectively), as well as PFS (p=0.04 and p=0.04, respectively). EREG and AREG expression levels were significantly correlated (r=0.73, p<0.01). Multivariate analysis revealed that AREG expression was significantly associated with OS and PFS.

Conclusion: R/M HNSCC patients with higher EREG and AREG gene expression appear to benefit more from cetuximab combined with chemotherapy than those with lower expression. The potential for these ligands as prognostic biomarkers for cetuximab-containing regimens requires further evaluation.

Citation Format: Yasunao Kogashiwa, Hitoshi Inoue, Kiyomi Kuba, Masanori Yasuda, Mitsuhiko Nakahira, Masashi Sugasawa. Expression of epiregulin/amphiregulin associates with prognosis in recurrent/metastatic head and neck cancer treated with cetuximab [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 2578.
Abstract 2589: Novel predictor of FGFR1 inhibition efficacy in non-small cell lung cancer
Authors: Quintanal-Villalonga Álvaro , Ferrer Irene , Marrugal Ángela , Ojeda-Márquez Laura , Zugazagoita Jon , García-Redondo Laura , López-Ríos Fernando , Montuenga Luis , Molina-Pinelo Sonia , Molina-Pinelo Sonia , Carnero Amancio , Paz-Ares Luis
Published: August 2018

Fibroblast growth factor receptor (FGFR)1 has been associated with tumorigenesis in a variety of tumors, including lung cancer. FGFR1 amplification is detected in up to 20% of lung squamous cell carcinomas, and was initially related to tumorigenesis and to response to FGFR inhibitors in preclinical models of this pathology. These data encouraged the establishment of FGFR1 amplification as the main eligibility criterion for inclusion of patients in FGFR inhibitors clinical trials. However, the use of FGFR inhibitors in FGFR1-amplified tumors has shown limited success, with only 5-10% of selected patients showing partial response, suggesting that this genomic aberration may not be a good predictive biomarker for the efficacy of these inhibitors. In this work, we provide in vitro and in vivo data showing that the oncogenic effects of FGFR1 expression depend on the expression of the adhesion molecule N-cadherin in non-small cell lung cancer (NSCLC). In line with these results, FGFR1 expression correlates with poorer prognosis only in tumors with high N-cadherin levels in two independent NSCLC patient cohorts. We observed that high FGFR1 expression alone is not sufficient to predict FGFR inhibition efficacy in lung cancer cell lines and patient-derived xenografts, with only high FGFR1- and high N-cadherin-expressing models responding to selective FGFR inhibitors. Altogether, our data show that the determination of the expression of FGFR1 alone is not sufficient to predict FGFR inhibition efficacy. The co-determination of N-cadherin expression may optimize patient selection for this therapeutic strategy.

Citation Format: Álvaro Quintanal-Villalonga, Irene Ferrer, Ángela Marrugal, Laura Ojeda-Márquez, Jon Zugazagoita, Laura García-Redondo, Fernando López-Ríos, Luis Montuenga, Sonia Molina-Pinelo, Sonia Molina-Pinelo, Amancio Carnero, Luis Paz-Ares. Novel predictor of FGFR1 inhibition efficacy in non-small cell 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 2589.
Abstract 2621: Genomic determinants of progression and response to therapy in prospectively characterized glioma patients
Authors: Jonsson Philip , Lin Andrew L. , Ogilvie Shahiba L. , Chavan Shweta S. , McKeown Andrew T. , DiStefano Natalie M. , Rosenblum Marc , DeAngelis Lisa M. , Mellinghoff Ingo K. , Taylor Barry S.
Published: August 2018

While the genomic landscape of low- and high-grade gliomas has been characterized and incorporated into further disease classification, its relationship to disease progression and treatment response remains poorly understood. To address this question, we integrated prospective clinical sequencing of 1,007 primary and recurrent tumors from 924 glioma patients with clinical and treatment phenotypes. Genomic alterations in effectors of cell cycle progression were a biomarker of aggressive disease in 1p19q intact IDH-mutant disease, arising preferentially in enhancing and recurrent tumors. When present at recurrence, the lesions were associated with rapid disease progression. These alterations were also present in all astrocytic tumors that ultimately relapsed with alkylating therapy-associated hypermutation. Analysis of matched pre-treatment and post-progression tumors indicated that cell cycle alterations preceded the emergence of hypermutation. In total, 391 patients (42%) harbored a potentially therapeutically actionable lesion in their tumor of which 73 patients (19%) received a diversity of targeted therapies. Both the type of mutation and its clonality were associated with therapeutic sensitivity in this cohort. For instance, RAF dimer-dependent BRAF hotspot mutations arose predominantly in IDH-wildtype glioblastomas, were subclonal, and affected patients did not respond to MAPK-directed therapy. In contrast, BRAF V600 hotspot mutations arose clonally in histologically distinct gliomas, both low- and high-grade, and responded to MAPK-directed therapy (either RAF, MEK or ERK inhibition). Collectively, these data reveal previously unrecognized genomic determinants of disease progression and treatment response in diverse types of glioma and serve as a rationale for utilizing genomic information in clinical care of patients with glioma.

Citation Format: Philip Jonsson, Andrew L. Lin, Shahiba L. Ogilvie, Shweta S. Chavan, Andrew T. McKeown, Natalie M. DiStefano, Marc Rosenblum, Lisa M. DeAngelis, Ingo K. Mellinghoff, Barry S. Taylor. Genomic determinants of progression and response to therapy in prospectively characterized glioma patients [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 2621.