bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantification of Tremolite in Friable Material Coming from Calabrian Ophiolitic Deposits by Infrared Spectroscopy
Authors: Campopiano Antonella , Olori Angelo , Cannizzaro Annapaola , Iannò Antonino , Capone Pietro Paolo
Published: August 2015

The aim of this study is to identify the infrared absorption band suitable for quantifying tremolite in three powdered samples (fine, medium, and large size classes) coming from a quarry of ophiolitic friable rocks in the western part of the Calabria region of Italy. Three IR bands were considered: OH stretching band between 3700 and 3650 cm−1, the stretching bands of the Si-O-Si linkage between 1200 and 900 cm−1, and the absorbance band at 756 cm−1attributable to tremolite. The amount of tremolite in the test samples was quantified by using the curve parameters of the three analytical bands. The quantitative analysis of tremolite using the band due to OH stretchings (3700–3650 cm−1) and the bands attributed to the Si-O-Si stretchings (1200–900 cm−1) showed high values for all test samples. Their use overestimated the tremolite amount because both bands were affected at the interfering mineral silicates such as talc, kaolinite, chlorite, and serpentinites. The abundant presence of antigorite in studied samples mainly in medium size class sample had a key role in our findings. The band at 756 cm−1was not affected at the interfering minerals and can be used for quantitative analysis of tremolite in sample coming from ophiolitic deposits.
Abstract 1004: Novel adjuvants from seaweed impede autophagy signaling in therapy-resistant residual pancreatic cancer
Authors: Aravindan Sheeja , Ramraj Satish Kumar , Khan Faizan H. , Herman Terence S. , Somasundaram Somasundaram T. , Aravindan Natarajan
Published: August 2015

Background: Identifying the drug-deliverables that target autophagy is crucial to finding a cure for pancreatic cancer (PC), as activated autophagy is associated with poor patient outcomes. Our recent studies recognized the anti-PC potential of an antioxidant-rich collection of seaweed polyphenols and identified potential compounds for the treatment of PC. Accordingly, we investigated whether such compounds could regulate autophagy in therapy-resistant PC cells in vitro and in residual PC in vivo.

Results: Human Panc-3.27 and MiaPaCa-2 cells were exposed to FIR with/without polyphenol from Spatoglossum asperum (SA-EA), Padina tetrastromatica (PT-EA), or Hormophysa triquerta (HT-EA). The cells were subjected to QPCR to examine transcriptional alterations in the following autophagy functional regulators: ATG3, ATG5, ATG7, ATG5, LC3A, LC3B, Beclin, Myd88, HMGB1, Rage, and TLRs 1-9. Using a clinically relevant mouse model of residual PC, we use tissue microarray (TMA) and immunohistochemistry (IHC) procedures to investigate the potential of polyphenol(s) to target ATG3, ATG5, ATG12, LC3A, LC3B, BECN1, and survivin after clinical radiotherapy. Radiation significantly increased the transcription of autophagy functional regulators in both lines. Seaweed polyphenols completely suppressed all investigated regulators in both lines. TMA-IHC analysis revealed the complete regulation of ATG3, ATG5, 12, LC3A, LC3B, BECN1, and survivin in residual PC following SA-EA, PT-EA, and HT-EA treatment.

Conclusions: These data demonstrate the autophagy blue print in therapy-resistant PC cells for the first time. Moreover, the data strongly suggest that the selected polyphenols could serve as effective adjuvants for current PC treatment modalities and may inhibit tumor relapse by comprehensively targeting therapy-orchestrated autophagy in residual cells.

Citation Format: Sheeja Aravindan, Satish Kumar Ramraj, Faizan H. Khan, Terence S. Herman, Somasundaram T. Somasundaram, Natarajan Aravindan. Novel adjuvants from seaweed impede autophagy signaling in therapy-resistant residual pancreatic cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1004. doi:10.1158/1538-7445.AM2015-1004
Abstract 101: WHSC1L1 as a therapeutic target in squamous cell carcinoma of the head and neck
Authors: Saloura Vassiliki , Vougiouklakis Theodore , Lingen Mark , Seiwert Tanguy , Vokes Everett , Nakamura Yusuke , Hamamoto Ryuji
Published: August 2015

Background: Squamous cell carcinoma of the head and neck (SCCHN) is a common malignancy with high recurrence rates and poor survival, thus new therapies are eagerly awaited. Protein lysine methyltransferases (PKMTs) have recently become one of the most important targets for drug discovery efforts, but only a few studies have explored their role in the pathogenesis of SCCHN. WHSC1L1, a nuclear SET-Suppressor of variegation 3-9, Enhancer of zeste and Trithorax-domain (NSD) PKMT and chromatin modifier, was reported to be amplified (8p11.23) in 6% of SCCHN tumors. This study aims to elucidate the pathophysiological role of WHSC1L1 as an oncogenic force in SCCHN and provide rationale for the development of inhibitors targeting WHSC1L1.

Methods: Cytotoxicity assays (MTTs) were conducted in one HPV-positive and one HPV-negative SCCHN cell line with WHSC1L1-specific siRNAs. Quantitative polymerase chain reaction (qPCR) and Western blotting were performed to examine WHSC1L1 expression levels in 14 SCCHN cell lines in comparison to a normal keratinocyte cell line (KGM). Immunohistochemistry (IHC) for WHSC1L1 in 115 patients with SCCHN and correlation of its expression with H3K36me2 was also performed. To identify candidate substrates that are directly methylated by WHSC1L1, in vitro methyltransferase assays using a recombinant protein library were conducted.

Results: siRNA-mediated knockdown of WHSC1L1 caused significant cell death in 2 SCCHN cell lines. Approximately 30% of SCCHN cell lines overexpressed WHSC1L1 compared to normal keratinocytes. WHSC1L1 expression as evaluated by IHC was significantly stronger in SCCHN compared to normal epithelium (Kruskal-Wallis test, p = 0.002) and 24% of SCCHN sections expressed high levels of WHSC1L1, compared to 6% of dysplastic lesions and 0% of normal epithelium sections. Interestingly, no association between WHSC1L1 expression levels and H3K36me2 was observed.

Conclusions: WHSC1L1 is genetically altered in multiple cancer types. In SCCHN, it is significantly overexpressed in 24% of the tumors and its knockdown caused significant growth suppression of both HPV-positive and HPV-negative SCCHN cell lines. Taken together, WHSC1L1 merits further investigation as a potential therapeutic target in SCCHN.

Citation Format: Vassiliki Saloura, Theodore Vougiouklakis, Mark Lingen, Tanguy Seiwert, Everett Vokes, Yusuke Nakamura, Ryuji Hamamoto. WHSC1L1 as a therapeutic target in squamous cell carcinoma of the head and neck. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 101. doi:10.1158/1538-7445.AM2015-101
Abstract 1018: Role of Stat3 vs Stat5 in the differentiation of HC11, mouse breast epithelial cells
Authors: Cass Jamaica , Niit Maximilian , Arulanandam Rozanne , Elliott Bruce , Raptis Leda
Published: August 2015

The Signal Transducer and Activator of Transcription (Stat)3 and Stat5 are transcription factors involved in normal breast development, and are hyperactivated in 30-50% of breast cancers. Stat5 is required for breast epithelial cell differentiation and is over-expressed in breast cancers with a more differentiated phenotype. On the other hand, constitutive over-activation of Stat3 can drive expression of genes involved in survival, migration and angiogenesis, while mutationally activated Stat3 (Stat3C) can transform cultured cells, indicating that Stat3 may play an important role in cancer etiology. Following activation of a number of growth factor or cytokine receptors such as interleukin-6 or expression of oncogenes such as Src, Stat3 is phosphorylated at tyr-705, dimerizes and migrates to the nucleus where it activates transcription from a number of genes involved in cell division and survival, such as survivin, Bcl-xL, Mcl1 and myc, while it downregulates expresssion of the tumor suppressor p53. We recently discovered a novel pathway of activation of Stat3: Engagement of cadherins (E-, N-cadherin or cadherin-11), cell to cell adhesion proteins induces a dramatic increase in the levels of the Rac1 and Cdc42 small GTPases, and this leads to interleukin-6 transcription, hence Stat3 activation.

The differentiation of HC11, nonneoplastic mouse breast epithelial cells requires prolactin, hydrocortisone and insulin, added at confluence. Since confluence activates Stat3, we examined the role of Stat3 upon breast epithelial cell differentiation, measured by cellular morphology and expression of the milk proteins, β-casein or whey acidic protein. Through pharmacological inhibition with CPA7 or S3I-201, our results demonstrate that Stat3 is, in fact, required for HC11 cell differentiation. In contrast, constitutive expression of mutationally activated Rac1 was found to block differentiation while inducing transformation.

In sharp contrast, our results indicate that Stat5 is upregulated by the differentiation cocktail but is unaffected by cell density, while expression of activated Stat5 promotes a more differentiated phenotype. Taken together, our results demonstrate that Stat3 and Stat5 may constitute independent prognostic markers as well as treatment targets for breast cancer.

Citation Format: Jamaica Cass, Maximilian Niit, Rozanne Arulanandam, Bruce Elliott, Leda Raptis. Role of Stat3 vs Stat5 in the differentiation of HC11, mouse breast epithelial cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1018. doi:10.1158/1538-7445.AM2015-1018
Abstract 102: KDM5B plays a central role in esophageal cancer progression
Authors: Nishida Naohiro , Kano Yoshihiro , Koseki Jun , Konno Masamitsu , Kawamoto Koichi , Doki Yuichiro , Mori Masaki , Ishii Hideshi
Published: August 2015

Esophageal cancer is consists of highly heterogeneous populations, which include cancer initiating cells, so-called cancer stem cells. Although histone modification is shown to be an essential factor for normal stem cell maintenance, the involvement of histone demethylase in cancer progression has been poorly understood. We investigated the functional roles of the Histone H3 lysine 4 (H3K4) demethylase KDM5B, a crucial epigenetic regulator that is required for normal embryonic development and cell growth. KDM5B knockdown resulted in the suppression of esophageal cancer cell growth, sphere formation and invasion ability and was associated with loss of epithelial cell marker expression. These tumor inhibitory effects were reverted subsequent to subcutaneous inoculation of these cells into immune-deficient mice. These results indicated that KDM5B plays an important role in maintaining cancer stem cells and justifies the rationale for studying the effects of continuous inhibition of this epigenetic factor in esophageal cancer.

Citation Format: Naohiro Nishida, Yoshihiro Kano, Jun Koseki, Masamitsu Konno, Koichi Kawamoto, Yuichiro Doki, Masaki Mori, Hideshi Ishii. KDM5B plays a central role in esophageal cancer progression. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 102. doi:10.1158/1538-7445.AM2015-102
Abstract 1072: DNA methylation profile analysis of gliomas revealed a change in methylation status during malignant progression
Authors: Akitake Mukasa , Saito Kuniaki , Aihara Koki , Nagae Genta , Omata Mayu , Otani Ryohei , Takayangi Shunsaku , Tanaka Shota , Narita Yoshitaka , Ueki Keisuke , Nishikawa Ryo , Nagane Motoo , Aburatani Hiroyuki , Saito Nobuhito
Published: August 2015

Low-grade glioma, especially astrocytomas often undergo malignant progression, and these transformations are a leading cause of death in patients with low-grade gliomas. However, the mechanisms underlying malignant tumor transformation are still not well understood. Recent evidence indicates that epigenetic deregulation is an important cause of gliomagenesis; therefore, we examined the epigenetic changes during malignant progression of gliomas. We used the Illumina Infinium Human Methylation 450K BeadChip to perform genome-wide DNA methylation analysis of 124 gliomas and four normal brains. These tumors comprised 37 grade IV gliomas, 32 grade III gliomas, and 55 grade II gliomas. This study sample included 26 matched-pairs of initial lower grade gliomas and recurrent tumors and 21 of the 26 recurring tumors recurred as malignant progressions.

Analyses of methylation profiles demonstrated that most low-grade gliomas in our sample (84%) had a CpG island methylator phenotype (G-CIMP). Remarkably, approximately 25% of recurrent malignant gliomas that had progressed from low-grade tumors with the G-CIMP status exhibited a characteristic partial demethylation of genomic DNA during malignant progression, but other recurrent gliomas showed no apparent change in DNA methylation pattern. Interestingly, we found that most loci that were demethylated during malignant progression were located outside of CpG islands. The information of histone modifications patterns in normal human astrocytes and embryonal stem cells also showed that the ratio of active marks at the site corresponding to DNA demethylated loci in G-CIMP-demethylated tumors was significantly lower; this finding indicated that most demethylated loci in G-CIMP-demethylated tumors were likely transcriptionally inactive. A small number of the genes that were upregulated and had demethylated CpG islands were associated with cell cycle-related pathway. Here, we demonstrated that partial DNA demethylation occurred during malignant transfomrmation of a subset of lower grade gliomas.

Citation Format: Mukasa Akitake, Kuniaki Saito, Koki Aihara, Genta Nagae, Mayu Omata, Ryohei Otani, Shunsaku Takayangi, Shota Tanaka, Yoshitaka Narita, Keisuke Ueki, Ryo Nishikawa, Motoo Nagane, Hiroyuki Aburatani, Nobuhito Saito. DNA methylation profile analysis of gliomas revealed a change in methylation status during malignant progression. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1072. doi:10.1158/1538-7445.AM2015-1072
Abstract 1077: Use of the SVClassify algorithm to classify pediatric solid tumor translocation variant calls as likely true or false positives
Authors: Harenza Jo Lynne , Parikh Hemang M. , Wei Jun S. , Wen Xinyu , Sindiri Sivasish , Patidar Rajesh , Salit Marc , Meltzer Paul S. , Khan Javed , Zook Justin
Published: August 2015

With the advent of next-generation sequencing technologies, a variety of structural variant (SV) calling algorithms have been developed. However, these algorithms are generally not sensitive and specific, in part because they are biased toward identification of specific types or lengths of SVs. Thus, concordance among algorithms is often very low. At the National Institute of Standards and Technology (NIST), we have previously rigorously characterized sequencing biases across multiple sequencing platforms for the candidate NIST reference material, RM 8398 (the genome of individual NA12878). This yielded a high-confidence set of SNP and small indel (<40 bp) variant calls. To extend our methods to SVs, we have developed SVClassify, which classifies SVs as likely true or false positive variants by combining evidence from one or more sequencing datasets. For NA12878, we were able to separate a set of validated deletions from random genomic regions with false positive and false negative rates less than 5%. We also found that the set of validated deletions clustered into different categories, including heterozygous Alu deletions, homozygous Alu deletions, and other heterozygous deletions. Until now, SVClassify has only been used for classification of large deletions on the non-cancerous genome, NA12878. In order to assess the sensitivity and specificity of SVClassify for correctly classifying translocations, we are using the RSVSim R package to simulate different numbers of translocations within repeat regions of the human genome. Furthermore, we will investigate the performance of SVClassify on cancer genomes, particularly pediatric solid tumors, which exhibit extensively rearranged genomes compared to their normal counterparts. To do so, pediatric tumor and normal datasets from multiple sequencing technologies will be integrated. To represent a spectrum of translocations, we will assess variant calls from cancer genomes with varying degrees of rearrangements: neuroblastoma, Ewing sarcoma, and osteosarcoma. Finally, we will use SVclassify to classify candidate SV calls made using the Complete Genomics pipeline, as well as those made on Illumina datasets using the recently developed SMUFIN algorithm.

Citation Format: Jo Lynne Harenza, Hemang M. Parikh, Jun S. Wei, Xinyu Wen, Sivasish Sindiri, Rajesh Patidar, Marc Salit, Paul S. Meltzer, Javed Khan, Justin Zook. Use of the SVClassify algorithm to classify pediatric solid tumor translocation variant calls as likely true or false positives. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1077. doi:10.1158/1538-7445.AM2015-1077
Abstract 1079: Transcriptional profiling reveals uterine leiomyoma subtypes with distinct pathways and biomarkers of tumorigenesis
Authors: Mehine Miika , Kaasinen Eevi , Pitkänen Esa , Sarvilinna Nanna , Heinonen Hanna-Riikka , Mäkinen Netta , Sjöberg Jari , Aaltonen Lauri A.
Published: August 2015

Uterine leiomyomas, also known as fibroids, are benign smooth muscle tumors with an estimated prevalence of 77% among women of reproductive age. Although benign, they frequently cause a variety of health complications and are the leading cause of hysterectomy worldwide. Recent studies utilizing high-throughput sequencing have revealed recurrent and mutually exclusive mutations in a variety of genes, suggesting that distinct molecular pathways are involved in the initiation of leiomyoma tumorigenesis. The consequences of these mutations are poorly understood and expression signatures associated with these driver mutations may provide further insights. The aim of this study was to explore transcriptional differences between genetic subgroups of leiomyomas utilizing Affymetrix exon arrays and RNA-sequencing. We performed transcriptional profiling of ∼100 leiomyomas harboring different genetic drivers; these included leiomyomas harboring MED12 mutations, HMGA2/HMGA1 rearrangements, biallelic inactivation of FH and COL4A5-COL4A6 deletions. We identified a long non-coding transcript of RAD51B to be specifically upregulated in MED12 mutant leiomyomas. Genes involved in key metabolic pathways, including pentose phosphate pathway and glutathione biosynthesis, were specifically upregulated in FH-deficient leiomyomas. AKR1B10 was the most significantly upregulated gene in leiomyomas of the FH type. This gene was not expressed in other leiomyomas and may serve as a robust biomarker for FH-deficient leiomyomas. Overexpression of the proto-oncogene PLAG1 was specifically seen in leiomyomas harboring HMGA2 or HMGA1 aberrations, suggesting that these tumors exert their tumorigenic effect through dysregulation of PLAG1. This was supported by identification of one uterine leiomyoma harboring a translocation of PLAG1 resulting in a similar overexpression. While this study highlights the importance of stratifying each leiomyoma into a specific subgroup, it also shows that several genes are commonly dysregulated among all leiomyomas. Targeting these genes would be ideal in developing treatments for this disease.

Citation Format: Miika Mehine, Eevi Kaasinen, Esa Pitkänen, Nanna Sarvilinna, Hanna-Riikka Heinonen, Netta Mäkinen, Jari Sjöberg, Lauri A. Aaltonen. Transcriptional profiling reveals uterine leiomyoma subtypes with distinct pathways and biomarkers of tumorigenesis. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1079. doi:10.1158/1538-7445.AM2015-1079
Abstract 1106: Genome-wide CRISPR-Cas9 screens reveal candidate therapeutic targets and tumor suppressor genes for human glioma
Authors: Ding Yu , Toledo Chad , Hoellerbauer Pia , Basom Ryan , Girad Emily , Lee Eunjee , Corrin Philip , Lin Qi , Li Xiao-Nan , Nam Do-Hyun , Lee Jeongwu , Zhu Jun , Pollard Steven , Delrow Jeffery , Olson Jim , Paddison Patrick J.
Published: August 2015

Glioblastoma multiforme (GBM) is the most aggressive and common form of brain cancer in adults. There are currently no effective therapies for GBM. Even with standard of care treatments, such as surgery, radiation, and chemotherapy, ∼90% of adult patients die within 2 years of diagnosis. Our inability to develop new more effective therapies may arise from pre-clinical models that inadequately predict therapeutic window and the fact that many new GBM drugs are “hand-me-downs” from other cancers, not specifically developed for treating brain tumors. To identify patient-tailored drug targets for GBM, our group has performed a series of functional genetic screens in patient derived GBM stem-like cells (GSCs) and also non-transformed human neural stem cells (NSCs). GSCs retain tumor-initiating potential and tumor-specific genetic and epigenetic signatures, even during extended outgrowth in serum-free culture. NSCs represent non-transformed candidate cell of origin controls, which share similar gene expression signatures and identical in vitro growth conditions. Using these systems along with RNAi or CRISPR/Cas9 platforms, we have identified multiple molecular vulnerabilities specific to GSCs, which appear to be largely driven by oncogenic transformation, in processes ranging from kinetochore regulation to 3′ pre-mRNA splice site recognition. At this meeting, we present our latest findings from genome-wide CRISPR-Cas9 gene knockout screens in multiple GSC and NSC isolates. These include validation studies of patient tumor-lethal genes using gene knockout rather than gene knockdown technology. In addition, we will present validation studies of gene products growth limiting for NSC expansion/self-renewal from these screens, a subset of which are candidate tumor suppressors for glioma. Strengths and weaknesses of using gene editing technology and GSC isolates for identification of therapeutic targets will be discussed.

Citation Format: Yu Ding, Chad Toledo, Pia Hoellerbauer, Ryan Basom, Emily Girad, Eunjee Lee, Philip Corrin, Qi Lin, Xiao-Nan Li, Do-Hyun Nam, Jeongwu Lee, Jun Zhu, Steven Pollard, Jeffery Delrow, Jim Olson, Patrick J. Paddison. Genome-wide CRISPR-Cas9 screens reveal candidate therapeutic targets and tumor suppressor genes for human glioma. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1106. doi:10.1158/1538-7445.AM2015-1106
Abstract 112: FTY720-P is a potent inhibitor of class I histone deacetylases that enhances histone acetylation, reactivates ERα expression, and increases hormonal therapeutic sensitivity of breast cancer
Authors: Hait Nitai C. , Avni Dorit , Yamada Akimitsu , Milstien Sheldon , Takabe Kazuaki , Spiegel Sarah
Published: August 2015

Hormonal therapies, including ovarian ablation, ER antagonists, and aromatase inhibitors, are the standards of care for treatment of ERα positive breast cancer. However, development of resistance to hormone therapies in advanced breast cancer is a major obstacle. Moreover, estrogen receptor-α (ERα)-negative breast cancer is clinically aggressive and does not respond to conventional estrogen targeted therapies. Strategies that lead to re-expression of ERα could sensitize breast cancers to selective ER modulators. FTY720/Fingolimod, a sphingosine analog, is an FDA-approved pro-drug for treatment of multiple sclerosis that also has anticancer actions that are not yet well understood. We have now found that FTY720 is phosphorylated in breast cancer cells by nuclear sphingosine kinase 2 and accumulates there. Nuclear FTY720-P in turn is a potent inhibitor of class I histone deacetylases (HDACs) that enhances histone acetylations and gene expression independently of its known effects on canonical signaling through sphingosine-1-phosphate receptors. In ERα negative human and murine breast cancer cells, FTY720 reactivated expression of silenced ERα and sensitized them to tamoxifen. Moreover, oral administration of clinically relevant doses of FTY720 to mice bearing ERα negative syngeneic breast tumors also re-expressed ERα and increased therapeutic sensitivity to tamoxifen in vivo more potently than a known HDAC inhibitor. Our work suggests that FTY720 is a promising strategy for effective treatment of conventional hormonal therapy-resistant breast cancer and triple-negative breast cancer. Supported by NIH grant RO1CA061774 and the Department of Defense BCRP program award W81XWH-14-1-0086 (S. Spiegel).

Citation Format: Nitai C. Hait, Dorit Avni, Akimitsu Yamada, Sheldon Milstien, Kazuaki Takabe, Sarah Spiegel. FTY720-P is a potent inhibitor of class I histone deacetylases that enhances histone acetylation, reactivates ERα expression, and increases hormonal therapeutic sensitivity of breast cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 112. doi:10.1158/1538-7445.AM2015-112
Abstract 1125: Oncogenic PIK3CA mutations reprogram glutamine metabolism in colorectal cancers
Authors: Hao Yujun , Samuels Yardena , Li Qingling , Krokowski Dawid , Brunengraber Henri , Hatzoglou Maria , Zhang Guo-Fang , Vogelstein Bert , Wang Zhenghe
Published: August 2015

Glutamine addiction is a major metabolic reprogramming event that occurs in cancer cells. Many tumors exhibit oncogene-dependent addiction to glutamine. PIK3CA, which encodes the p110α catalytic subunit of phosphatidylinositol 3-kinase α, is the most frequently mutated oncogene in human cancers. However, whether PIK3CA mutations reprogram cancer metabolism is an important unaddressed question. Here we show that oncogenic PIK3CA mutations reprogram glutamine metabolism by up-regulating glutamate pyruvate transaminase 2 (GPT2) in colorectal cancer (CRC) cells, thereby rendering them addicted to glutamine. We demonstrated that induction of GPT2 by mutant p110α is necessary and sufficient to render CRC cells addicted to glutamine. Moreover, aminooxyacetate, which inhibits enzymatic activity of aminotransferases including GPT2, suppresses xenograft tumor growth of CRCs with PIK3CA mutations, but not CRCs with WT PIK3CA. Thus our data suggest that targeting glutamine metabolism may be an effective approach to treat CRC patients harboring PIK3CA mutations. Mutant p110α up-regulates GPT2 gene expression through an AKT-independent PDK1-RSK2-ATF4 signaling axis. We showed that ATF4 is a transcription factor that activates GPT2 gene expression. We further demonstrated that mutant p110α activates RSK2 kinase through PDK1. Activated RSK2 then phosphorylates ATF4 at the serine residue 245, which in turn recruits deubiquitinase USP8 and protects ATF4 from ubiquitin-mediated degradation. Lastly, using [13C5-]glutamine isotope-tracing technology, we showed that PIK3CA mutant CRCs convert more glutamine to α-keto-glutarate to replenish the tricarboxylic acid (TCA) cycle to generate ATP. Together, our data establish oncogenic PIK3CA mutations as a cause of glutamine addiction in CRCs.

Citation Format: Yujun Hao, Yardena Samuels, Qingling Li, Dawid Krokowski, Henri Brunengraber, Maria Hatzoglou, Guo-Fang Zhang, Bert Vogelstein, Zhenghe Wang. Oncogenic PIK3CA mutations reprogram glutamine metabolism in colorectal cancers. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1125. doi:10.1158/1538-7445.AM2015-1125
Abstract 1133: Plk1 phosphorylation of PTEN causes a tumor-promoting metabolic state
Authors: li zhiguo , jie li , xiaoqi Liu
Published: August 2015

One outcome of activation of the PI3K pathway is increased aerobic glycolysis, but the upstream signaling events that regulate the PI3K pathway, thus the Warburg effect, are elusive. Increasing evidence suggests that Plk1, a cell cycle regulator, is also involved in cellular events in addition to mitosis. To test whether Plk1 contributes to activation of the PI3K pathway, thus aerobic glycolysis, we have identified PTEN as a Plk1 substrate. We hypothesize that Plk1 phosphorylation of PTEN contributes to activation of the PI3K pathway and the Warburg effect. Our data show that overexpression of Plk1 leads to activation of the PI3K pathway and enhanced aerobic glycolysis. In contrast, inhibition of Plk1 causes markedly reduced glucose metabolism in mice. Mechanistically, we show that Plk1 phosphorylation of PTEN and Nedd4-1 results in PTEN inactivation. Finally, we show that Plk1 phosphorylation of PTEN promotes tumorigenesis in both its phosphatase-dependent and -independent pathways.

Note: This abstract was not presented at the meeting.

Citation Format: zhiguo li, li jie, Liu xiaoqi. Plk1 phosphorylation of PTEN causes a tumor-promoting metabolic state. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1133. doi:10.1158/1538-7445.AM2015-1133
Abstract 1146: Global profiling of SPARC-regulated metabolic pathways in ovarian cancer
Authors: Taylor Sherine , Sanchez Christian , Adrees Amna , Ozbek Hale Nur , Sahni Harjapjit , Said Neveen A.
Published: August 2015

We have previously reported the tumor suppressor effect of SPARC in ovarian cancer through inhibiting cancer cell growth and their interactions within the peritoneal milieu. In the present study, we sought to determine the effect of SPARC on metabolic perturbations associated with ovarian cancer using a syngeneic murine ovarian cancer model in SPARC knockout (KO) mice and their wildtype (WT) counterparts. Murine ID8 ovarian cancer cell line were injected intraperitoneally in SPARC KO and WT mice. Matched intraperitoneal tumor tissue, and ascitic fluid were harvested 6 weeks post-injection of ID8 cells and were subjected to global biochemical metabolomic profiling. In tandem, WT and KO tumors were dissected by LCM-microdissected and were subjected to gene expression profiling. Metabolomic profiling of SPARC KO tumors and ascites revealed significantly altered metabolites associated with glucose, energy, amino acid, and lipid metabolism, as well as redox homeostasis. Integrated transcriptome and metabolome analysis of the top significantly upregulated genes and metabolites in the KO compared to WT tumors and ascitic fluid revealed that the major pathways upregulated in absence of SPARC are those involved in: conversion of glucose to acetyl CoA and entry into the citric acid (TCA) cycle, respiratory electron transport and oxidative phosphorylation (SUCLG2; NDUFAB1; ATP5F1; UQCRH; ATP5H; COX5B; NDUFV1; ATP5O; IDH3B/ succinate, fumarate and pyruvate), protein metabolism (EIF5A; PREB; EIF4H; DAD1; STT3A; RPL4; SUMO1; CCT4; CCT2; IGFBP5; HSPA5; EIF3A; EIF4B; RPS19; EIF3E/ mannose; N-acetylneuraminate; N-glycolylneuraminate; glutamate; spermidine), fatty acid beta oxidation (HADH; TPI1; LPL/glycerol), purine nucleotides de novo biosynthesis and salvage (ATP5F1; ATP5H; PAICS; ATP6V1G1/ aspartate; glycine; glutamate; fumarate). Together, these data provide novel insight on the molecular mechanisms of the SPARC-induced metabolic perturbation associated with ovarian cancer that can be translated into diagnostic and prognostic biomarkers of the disease.

Citation Format: Sherine Taylor, Christian Sanchez, Amna Adrees, Hale Nur Ozbek, Harjapjit Sahni, Neveen A. Said. Global profiling of SPARC-regulated metabolic pathways in ovarian cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1146. doi:10.1158/1538-7445.AM2015-1146
Abstract 1153: Effective treatment of cancer associated cachexia by AV-380, a GDF15 inhibitory antibody
Authors: Lerner Lorena , Tao Nianjun , Krieger Brian , Nicoletti Richard , Feng Bin , Ismail Nesreen , Winston William , Zhang Yanyu , Jiang Jinwei , Weiler Solly , Gyuris Jeno
Published: August 2015

Background:

One of the most lethal and debilitating effects of cancer is the development of cancer-related anorexia-cachexia syndrome (CACS). It affects the majority of advanced cancer patients and is thought to be responsible for up to ∼30% of all cancer deaths. CACS is a complex metabolic syndrome associated with malnutrition and severe involuntary weight loss due to the loss of muscle and fat tissue, as well as the clinical manifestation of anemia, inflammation and suppression of immune functions. The precise molecular mechanisms responsible for cancer cachexia are poorly understood, thus limiting the development of effective therapeutics. Current evidence suggests that a pro-inflammatory state may be responsible for many of the symptoms associated with CACS. Growth Differentiation Factor 15 (GDF15) is a pro-inflammatory cytokine whose circulating levels are significantly increased in cachectic cancer patients and several animal models of cancer cachexia. Here we demonstrate that the inhibition of GDF15 function results in the compete reversion of the phenotypic and metabolic changes associated with CASC.

Methods:

Mice bearing HT-1080 human fibrosarcoma xenografts have increased plasma GDF15 levels and develop cachexia were used in this study. Tumor bearing animals were treated either with AV-380, a GDF15 neutralizing antibody or IgG1 control. The effect on body weight, muscle/fat mass and organ sizes were assessed. Metabolic changes induced by the treatment were measured by a comprehensive laboratory animal monitoring system (CLAMS).

Results:

Treatment with AV-380 restored body weight, muscle and fat mass as well as normal organ sizes. Analyses of the CLAMS data demonstrated that mice receiving AV-380 reversed the phenotypic and metabolic changes associated with the cachexia induced by this tumor model. Moreover, AV-380 treated mice showed an increase in locomotor activity and energy expenditure, achieving levels similar to non tumor bearing control animals.

Conclusions:

Inhibition of GDF15 function completely reverted body weight loss, restored normal body composition and triggered a catabolic to anabolic metabolic switch in this cancer cachexia model. The data highlights the therapeutic potential of the GDF15 inhibitory antibody AV-380 for the treatment for CACS.

Citation Format: Lorena Lerner, Nianjun Tao, Brian Krieger, Richard Nicoletti, Bin Feng, Nesreen Ismail, William Winston, Yanyu Zhang, Jinwei Jiang, Solly Weiler, Jeno Gyuris. Effective treatment of cancer associated cachexia by AV-380, a GDF15 inhibitory antibody. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1153. doi:10.1158/1538-7445.AM2015-1153
Abstract 1156: Widespread deficiency of ASS1 in uveal melanoma and sensitivity to pegylated arginine deiminase
Authors: Khadeir Ramsay S. , Phillips Melissa M. , Sgoo Mandeep S. , Arora Amit , Cohen Victoria , Thaung Caroline , Szlosarek Peter W.
Published: August 2015

Uveal melanoma, involving the iris, choroid and ciliary body, is the commonest intraocular tumor in adults. Approximately half of these patients will develop metastasis with a high mortality despite currently available systemic therapies including immune checkpoint blockade. The urea cycle enzyme argininosuccinate synthetase 1 (ASS1), responsible for arginine synthesis, is downregulated in melanoma and other cancers and these are therefore sensitive to arginine deprivation therapy. In early phase trials of the arginine depletor pegylated arginine deiminase, ADI-PEG20, uveal melanoma, in particular, was identified with potential for further therapeutic development. Here, we tested uveal melanoma cell lines for sensitivity to ADI-PEG20 and analyzed enucleated tumors for ASS1 expression to assess the extent of ASS1 deficiency.

Methods: ASS1 gene and protein expression were assessed in three uveal melanoma cell lines (OMM1, OMM2.5 and Mel270) by real-time quantitative PCR (qPCR) and western blot analysis, respectively. Sensitivity to ADI-PEG20 was performed using the cell viability MTS assay. We screened 102 enucleated choroidal and ciliary body melanomas for ASS1 protein using red chromogen for the immunohistochemistry (IHC) and selected the most positive area for scoring.

Results: The uveal melanoma cell lines expressed negligible ASS1 mRNA with a complete absence of ASS1 protein. All three ASS1 negative uveal melanoma cell lines were sensitive to ADI-PEG20 by day 6 of the MTS assay, whereas an ASS1-expressing positive control cell line was resistant. There was a convincing lack of ASS1 expression (<5% staining) in the majority of uveal melanomas (75/102; 74%) and where ASS1 was present (5-30% staining) in the remainder (27/102; 26%) this was due to a mixture of melanoma cells and intratumoral macrophages, the latter being confirmed with CD68 (IHC) in the cases with the highest ASS1 expression.

Conclusion: ASS1 is absent in the tested uveal melanoma cell lines and predisposes to arginine sensitivity with ADI-PEG20 in vitro. Most primary uveal melanomas have a marked deficiency of ASS1, representing a good target for exploring arginine deprivation further in the clinic, either alone or in combination with rationally selected agents. A trial of ADI-PEG20 combined with carboplatin and paclitaxel is planned in metastatic malignant melanoma with an expanded cohort in patients with uveal disease.

Citation Format: Ramsay S. Khadeir, Melissa M. Phillips, Mandeep S. Sgoo, Amit Arora, Victoria Cohen, Caroline Thaung, Peter W. Szlosarek. Widespread deficiency of ASS1 in uveal melanoma and sensitivity to pegylated arginine deiminase. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1156. doi:10.1158/1538-7445.AM2015-1156
Abstract 1166: ASCT2: A novel metabolic target for cancer therapy
Authors: Pore Nabendu , King Wanda , Lekstrom Kristen , Wilson Susan , Hollingsworth Robert , Tice David A. , Michelotti Emil
Published: August 2015

Uncontrolled proliferation of cancer cells is often fueled by the deregulation of various cellular signaling pathways. Such deregulation also frequently rewires the metabolism of cancer cells in order to meet their increased need for energy and nutrients required for growth and proliferation. In the process, tumor cells produce high levels of anabolic intermediates required for biosynthesis of macromolecules and redox homeostasis. Many of these building blocks are derived from tri-carboxylic acid cycle (TCA) intermediates that need to be replenished in a process called anapleurosis. Glutaminolysis, the process in which glutamine (Gln) is converted into TCA intermediates by glutaminase is one of the key pathways that feeds anapleurosis in cancers. Many tumor cell lines fail to grow in the absence of glutamine and are therefore addicted to this nutrient. Glutamine is a preferred substrate for ASCT2, a member of ASC family of amino acid transporters, and thus this transporter may play a role in this addiction. We screened a variety of cancer cells for their dependence on Gln and determined that a significant subset of cell lines require this important nutrient. Biochemical experiments indicated that the ASCT2 family of proteins is the main driver of Gln transport. In agreement with these findings, shRNA-mediated knock down of ASCT2 significantly inhibited 14C-Gln uptake and tumor cell proliferation. Expression of an shRNA-resistant ASCT2 gene rescued both the inhibition of cell proliferation and transport of Gln. Furthermore, stable knockdown of ASCT2 induced autophagy and significantly slowed growth in vivo of various tumor types such as colon carcinoma, prostate carcinoma, and in neuroblastoma. The above findings identify ASCT2 as an attractive target for therapeutic intervention.

Note: This abstract was not presented at the meeting.

Citation Format: Nabendu Pore, Wanda King, Kristen Lekstrom, Susan Wilson, Robert Hollingsworth, David A. Tice, Emil Michelotti. ASCT2: A novel metabolic target for cancer therapy. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1166. doi:10.1158/1538-7445.AM2015-1166
Abstract 1173: Extracellular ATP is internalized through not only macropinocytosis but also other endocytic process and promotes growth of human lung cancer cells with Ras mutations
Authors: Qian Yanrong , Wang Xuan , Li Yunsheng , Cao Yanyang , Wu Shiyong , Chen Xiaozhuo
Published: August 2015

Within a tumor, extracellular ATP (exATP) concentrations are in the range of several hundred micromolars or higher, 103-104 times higher than those in normal tissues1. We recently showed that extracellular ATP, within the intratumoral concentrations, was internalized by Ras-mutated (Rasmut) A549 human lung cancer cells through macropinocytosis, elevated intracellular ATP levels and rescued cancer cells under various stresses2. However, macropinocytosis3 alone could not account for all the elevated intracellular ATP increase. Here, we show that other endocytic processes, in addition to macropinocytosis, also contributed to the internalization of exATP in A549 and H1299 human lung cancer cells. Cell viability assays, intracellular ATP luminescence measurement assays, fluorescent microscopy were used in this study. First, high-molecular-weight (HMW) dextran uptake assay indicated that A549 and H1299, both Rasmut cancer cells, exhibited a phenotype of macropinocytosis. The colocalization of the red fluorescent HMW dextran and green nonhydrolyzable ATP analog inside the cells indicated that extracellular ATP was internalized by macropinocytosis. In contrast, significantly fewer macropinosomes were found in NL-20 noncancerous lung cells. In addition, the colocalization of low-molecular-weight (LMW) dextran, an endocytic tracer, and ATP analog indicated the internalization of exATP through non-macropinocytic-endocytosis in both lung cancer cell lines. Interestingly, when both red HMW dextran and green LMW dextran were applied to cancer cells, not only colocalization, but also some green-only endosomes were observed, strongly suggesting that both endocytic processes were responsible for exATP internalization. Collectively, these data indicated for the first time that other endocytic processes in addition to macropinocytosis contributed to the internalization of exATP in human lung cancer cells with Rasmut. This finding may significantly enhance our understanding of energy hemostasis within cancer cells and the Warburg effect, which in turn facilitates the development of anticancer therapeutics targeting the endocytic processes and Ras mutations as well as novel anticancer strategies.

1. Pellegatti, et al. (2008). PLoS ONE 3, e2599.

2. Qian, et al. (2014). Cancer Letters 351, 242-251.

3. Commisso, et al. (2013). Nature 497, 633-637.

Citation Format: Yanrong Qian, Xuan Wang, Yunsheng Li, Yanyang Cao, Shiyong Wu, Xiaozhuo Chen. Extracellular ATP is internalized through not only macropinocytosis but also other endocytic process and promotes growth of human lung cancer cells with Ras mutations. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1173. doi:10.1158/1538-7445.AM2015-1173
Abstract 1176: The effect of resveratrol combined with dichloroacetate (DCA) on breast cancer cell lines and MCF-10a noncancerous cells
Authors: Piepenbrink Sarah , Sisler Dan , Feirer Russ
Published: August 2015

Resveratrol, (3,5,49-trihydroxy-trans-stilbene), was first reported to act as a chemo-preventative anticancer compound in mice by Jang et al. in 1997 and has been shown to induce apoptosis and reduce both cell viability and mitotic index in many cancer cell lines. Earlier work in our lab found that it affects glucose utilization by decreasing glucose uptake by MCF-7 cells. The present study examined combinations of resveratrol with DCA, a compound that affects mitochondrial metabolism (reversing the Warburg Effect). A goal of this study was to determine if DCA might sensitize cancer cells to other chemotherapeutic compounds that affect glucose metabolism, such as resveratrol. Glucose uptake and lactate production by treated cells were measured, and Western blots were used to estimate levels of several proteins, including cleaved PARP and p21. Both resveratrol and DCA were found to reduce cell viability of treated breast cancer cell lines. Resveratrol, but not DCA, was found to induce caspase-3,7, a measure of apoptosis. This suggests that resveratrol and DCA may affect viability via different mechanisms. More importantly, a synergistic effect of these compounds on cell viability was observed, where DCA was found to enhance the anti-proliferative effect of resveratrol.

Citation Format: Sarah Piepenbrink, Dan Sisler, Russ Feirer. The effect of resveratrol combined with dichloroacetate (DCA) on breast cancer cell lines and MCF-10a noncancerous cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1176. doi:10.1158/1538-7445.AM2015-1176