bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract 2435: Novel regulators of renal cancer metabolism
Authors: Kho EunYoung , Kirkman Richard , Shim Eun-Hee , Goash Arindam , Sudarshan Sunil 
Published: May 2015

Abstract
Renal cell carcinoma (RCC) is among the 10 most common malignancies in the U.S. Clear cell RCC (ccRCC) is the most common histology. Recent analysis of ccRCC by the Cancer Genome Atlas (TCGA) demonstrates the reduced mRNA expression of several enzymes of the tricarboxylic acid (TCA) cycle. Moreover, reduced TCA enzymes expression is associated with worse prognosis. These data indicate a transcriptional program that promotes a bioenergetic shift. These studies prompted us to examine transcription factors that are known regulators of mitochondrial metabolism including the estrogen-related receptors (ERRs) and peroxisome proliferator-activated receptor γ (PPARγ) coactivators 1 (PGC-1s). Interestingly, mRNA analysis of RCC tissues and cell lines demonstrates the reduced expression of ERRγ and PGC-1α. Notably, prior analysis demonstrates putative ERR binding sites in the promoters of FH and MDH2, two genes encoding TCA enzymes with reduced expression in ccRCC. Promoter analysis of these genes with a luciferase reporter assay demonstrates that ERRγ and PGC-1α cooperate to regulate the expression of TCA enzymes indicating that reduced expression of these factors promotes reduced TCA enzyme expression in RCC.
Citation Format: EunYoung Kho, Richard Kirkman, Eun-Hee Shim, Arindam Goash, Sunil Sudarshan. Novel regulators of renal cancer metabolism. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2435. doi:10.1158/1538-7445.AM2014-2435
Abstract 2436: Regulation of breast cancer cell metabolism by the AMPK/ERR/PGC pathway
Authors: Audet-Walsh Étienne , Papadopoli David , St-Pierre Julie , Giguère Vincent 
Published: May 2015

Abstract
Reprogramming of energy metabolism is now considered a hallmark of cancer. Deciphering molecular mechanisms underlying this process is therefore necessary to understand malignant transformation and cancer progression, but also to develop novel therapeutic tools. In the present study, our aim was to discover potential molecular links between two major pathways involved in energy metabolism in breast cancer cells: the energy sensor AMPK (AMP-activated protein kinase) in relationship with the estrogen-related receptors (ERRα and ERRγ) and their coactivators PGC-1α and PGC-1β (peroxisome-proliferator activated receptor γ coactivator-1). Using microarray analysis and qRT-PCR validation, we showed that activation of AMPK significantly altered the expression of the ERRs and the PGCs as well as their metabolic target genes. Moreover, pathway analysis revealed that a significant subset of genes regulated by AMPK pharmacological activation for 1 and 4 days were associated with the ERR/PGC transcriptional programs. Using metabolomics tools, we demonstrated that the energetic remodeling following AMPK pharmacological activation depends in part on ERR/PGC in breast cancer cells. Indeed, the induction in glucose and glutamine uptake and usage by activated AMPK was decreased by half following impairment of the ERR/PGC axis. Moreover, total, uncoupled and coupled respirations were also significantly decreased by ≈50% following ERR/PGC siRNA-mediated knock down. In order to understand the role of the ERRs in the transcriptional regulation of downstream targets of AMPK, we performed chromatin immunoprecipitation followed by massively parallel DNA sequencing (ChIP-seq). Our results indicate that AMPK activation induces ERRs binding at the genomic scale, with the presence of 12,043 and 8,559 novel binding sites for ERRα and ERRγ, respectively. Basal, ERRs' binding to energy metabolism genes was already strong and did not change significantly after treatment. However, AMPK pharmacological activation induced ERRs binding to novel pathways such as numerous genes of the folate metabolism pathway. The biological consequence of the modulation of these pathways by the AMPK/ERR/PGC axis is presently under investigation. In conclusion, using transcriptomics, metabolomics and functional genomics, we revealed the interconnection of the AMPK with the ERR/PGC axis and the importance of this pathway in breast cancer cell metabolic states.
Citation Format: Étienne Audet-Walsh, David Papadopoli, Julie St-Pierre, Vincent Giguère. Regulation of breast cancer cell metabolism by the AMPK/ERR/PGC pathway. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2436. doi:10.1158/1538-7445.AM2014-2436
Abstract 2440: RNF5 mediates ER stress-induced degradation of SLC1A5 in breast cancer
Authors: Jeon Young Joo , Khelifa Sihem , Feng Yongmei , Lau Eric , Cardiff Robert , Kim Hyungsoo , Rimm David L. , Kluger Yuval , Ronai Ze'ev 
Published: May 2015

Abstract
Tumor cells have an altered metabolism that distinguishes it from their normal counterpart. Intriguingly, tumor cells show increased use of glutamine to fuel catabolic processes. Therefore, altered metabolic tumors have been considered as a good target for anticancer therapy. Ring finger protein 5 (RNF5) is an ER membrane-associated ubiquitin E3 ligase. RNF5 expression has been associated with breast cancer progression. We identified solute carrier family 1 member 5 (SLC1A5) as a possible RNF5 regulated protein using a MS analysis of breast cancer cells. SLC1A5 is a high affinity L-glutamine transporter, which is highly expressed in tumors such as breast, liver and lung. RNF5 promotes ubiquitination-mediated degradation of SLC1A5 in response to chemotherapeutic drugs known to induce ER stress. RNF5-mediated SLC1A5 instability attenuated mTOR signaling, leading to inhibition of tumor cell proliferation and promotion of apoptosis/autophagy. The loss of RNF5 in PyMT-MMTV crossed with RNF5 mutant animals developed less differentiated mammary tumors, which exhibit increased levels of SLC1A5. TMA analysis of human breast cancer tumors identified a fraction that exhibited an inverse correlation between RNF5 and SLC1A5 expression. Notably, reduced expression of SLC1A5 exhibited a strong association with improved prognosis of breast cancer. Taken together, our observations identify mechanisms underlying the control of SLC1A5 stability, and the implications of such regulation for mTOR signaling and breast cancer survival in response to therapy.
Citation Format: Young Joo Jeon, Sihem Khelifa, Yongmei Feng, Eric Lau, Robert Cardiff, Hyungsoo Kim, David L. Rimm, Yuval Kluger, Ze'ev Ronai. RNF5 mediates ER stress-induced degradation of SLC1A5 in breast cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2440. doi:10.1158/1538-7445.AM2014-2440
Abstract 2455: BRCA1 and BARD1 expression and localization in breast cell lines
Authors: Herrera Cristobal , Pérez Elisa , Blanco Elías , Gajardo Patricia , Carvallo Pilar 
Published: May 2015

Abstract
One of the principal functions of BRCA1 is to keep the integrity of DNA by homologous recombination which repairs DNA double strand breaks, thus its localization is mainly nuclear in a normal cell. BRCA1 nuclear function is enhanced by its interaction with BARD1, which promotes the import and nuclear retention of BRCA1 by masking its nuclear export signal. Therefore, the interaction of these two proteins is relevant in BRCA1 nuclear function. On the other hand, in tumor cell lines, splicing variants of BARD1 lacking the BRCA1 interaction domain have been described. The expression of these splicing variants of BARD1 could contribute to the loss of nuclear localization of BRCA1. Recently, our group found that a high percentage of triple negative breast cancer tumors showed cytoplasmic or no expression of BRCA1 (unpublished data). Our interest is to study the molecular mechanisms that explain the cytoplasmic localization of BRCA1 in breast cancer cells. We studied mRNA expression of BRCA1, BARD1 and BARD1β through RT-PCR and expression of both proteins by western blot, immunocytochemistry and immunofluorescence in two breast cancer cell lines (HCC1937: ER-, mutated in BRCA1, and T47D: ER+) and one non-tumor breast cell line (MCF10A). BRCA1 and BARD1 expression was coherent between immunocytochemistry and immunofluorescence assay. The HCC1937 cell line presented a weak BRCA1 protein expression mainly in the cytoplasm. The other cell lines had a high nuclear and weak cytoplasmic expression. BARD1 protein is expressed in the nucleus and cytoplasm in all cell lines. BARD1 full mRNA had an equal expression in the three cell lines, and its isoform BARD1β, which do not interact with BRCA1, was expressed at higher levels in tumor cell lines than in the non-tumor cell lines. However, T47D cell line showed nuclear localization of BRCA1 despite high levels of BARD1β mRNA. This suggests that BARD1β either does not express at protein level, or that full-length BARD1 levels are enough to keep BRCA1 in the nucleus. The study of molecular causes of BRCA1 localization in cell lines will allow us to better understand subcellular localization of BRCA1 in tumors and its interaction with BARD1. FONDECYT 1120200.
Citation Format: Cristobal Herrera, Elisa Pérez, Elías Blanco, Patricia Gajardo, Pilar Carvallo. BRCA1 and BARD1 expression and localization in breast cell lines. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2455. doi:10.1158/1538-7445.AM2014-2455
Abstract 2466: The tumor suppressor Merlin decreases TGFβ/Smad signaling in metastatic breast cancer cells
Authors: Jackson William P. , Kreitzburg Kelly M. , Das Shamik , Bailey Sarah K. , Metge Brandon J. , Samant Rajeev S. , Shevde-Samant Lalita R. 
Published: May 2015

Abstract
Background: Merlin is a tumor suppressor protein encoded by the NF2 gene. Mutations in NF2 have been implicated in neurofibromas, schwannomas, and mesothelioma. While the mutation rate of NF2 is low in breast cancer, our lab has previously demonstrated a loss of the Merlin protein in advanced stage breast cancers. We have shown that the matricellular metastasis-promoting protein osteopontin activates Akt which then marks Merlin for targeted proteasomal degradation. In the context of other cancers, Merlin has been shown to play a role in sensitization to contact inhibition, cell proliferation, inhibiting invasion, and the negative regulation of focal adhesion kinase. Merlin is also an upstream regulator of the Hippo pathway. However, the implications of the loss of Merlin in the context of breast cancer signaling pathways that promote tumor progression and metastasis have not been fully explored. Here we demonstrate a Merlin-dependent decrease in TGFβ signaling in metastatic breast cancer cells.
Methods: Using Ingenuity Pathway Analysis we analyzed a gene expression array comparing the triple-negative metastatic SUM159 breast cancer cells and their counterparts that were stably restored for Merlin expression. TGFβ was identified as a significant upstream regulator. TGFβ signaling was analyzed in these cells via a SBE4-luc luciferase assay. Signaling was further analyzed by Western blots for SMAD and phospho-SMAD proteins.
Results and Conclusions: Re-expression of Merlin in metastatic breast cancer cells with low-levels of endogenous Merlin decreases TGFβ signaling, demonstrated by decreased luciferase assay activity, decreased rSMAD expression, decreased coSMAD expression and increased iSMAD protein levels. Future studies will explore the nature of this Merlin-dependent decrease in TGFβ signaling.
Acknowledgments: R01CA138850 to L. A. Shevde
Citation Format: William P. Jackson, Kelly M. Kreitzburg, Shamik Das, Sarah K. Bailey, Brandon J. Metge, Rajeev S. Samant, Lalita R. Shevde-Samant. The tumor suppressor Merlin decreases TGFβ/Smad signaling in metastatic breast cancer cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2466. doi:10.1158/1538-7445.AM2014-2466
Abstract 2514: Towards homogenous adcs: A new site-specific antibody conjugation using bacterial transglutaminase (btg-adc)
Authors: Lhospice Florence , Bregeon Delphine , Belmant Christian , Represa Agnes , Boedec Angelique , Morel Yannis , Dennler Patrick , Schibli Roger , Romagne François 
Published: May 2015

Abstract
Purpose : Bacterial Transglutaminase (BTG) allows coupling on endogenous Q295 from an aglycosylated antibody. Here, the work relates to ADCs synthesis through BTG approach on mAbs with single point mutations and the study of stability, pharmacokinetics, as well as in vitro and in vivo efficacy of resulting BTG-ADCs. AdcetriS®, brentuximab vedotin, has been used as comparator, hence for consistency BTG-ADCs have been conjugated with the different linkage strategies (one step and two step) containing distally the same protease sensitive moiety compared to ADCETRIS®, i.e. valine-citrulline-PAB-MMAE.
Methods : . For synthesis, a two-step process has been designed consisting of coupling first a linker and coming back with a toxin, and affording versatility and efficiency. The DAR stability was monitored over one week in human and cynomolgus plasma by affinity capture/LC/MS. The pharmacokinetic profile was studied in rat and monitored by affinity capture/LC/MS for conjugated antibody and ELISA for total antibody. In vitro efficacy of ADCs conjugated using BTG was compared side-by-side with ADCETRIS® on Karpas 299 cells. In vivo efficacy was studied in xenogenic nude mice engrafted with Karpas 299 in SC with BTG ADCs or ADCETRIS at doses of 0.6mg/kg.
Results: BTG two-step process leads to ADCs with DAR of exactly 2.0 or 4.0 for antibodies with N297S or N297Q single point mutation respectively. The BTG ADCs were stable in human and cynomolgus plasma, with no degradation observed over 15 days in rats and furthermore with favorable total antibody clearance. In vitro efficacy for BTG ADCs DAR=4.0 was comparable to ADCETRIS (mean DAR=4) with respect to EC50 and plateau. In vivo efficacy for BTG ADC was demonstrated to be at least equivalent to ADCETRIS®.
Conclusions: Pre-clinical proof of concept is demonstrated for BTG coupling. When considering versatility, speed and efficiency of the process, BTG-ADC coupling should provide a promising technology for the next generation of homogeneous ADCs.
Citation Format: Florence Lhospice, Delphine Bregeon, Christian Belmant, Agnes Represa, Angelique Boedec, Yannis Morel, Patrick Dennler, Roger Schibli, François Romagne. Towards homogenous adcs: A new site-specific antibody conjugation using bacterial transglutaminase (btg-adc). [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2514. doi:10.1158/1538-7445.AM2014-2514
Abstract 2947: Regulation of PD-L1 expression in human melanoma by NF-kB
Authors: Gowrishankar Kavitha , Gunatilake Dilini , Gallagher Stuart , Tiffen Jessamy , Hersey Peter 
Published: May 2015

Abstract
Background : Antibodies targeting the immune check point inhibitor programmed death receptor 1 (PD-1) and its ligand (PD-L1) have been associated with relatively high response rates that appear durable in most patients. Past studies have shown the percentage of melanoma expressing the ligand for PD1, PD-L1 varies from 38 to 53% depending on the cutoff used to determine positivity and the antibodies used. In the majority of melanoma, expression of PD-L1 was associated with tumor infiltrating lymphocytes (TIL) and was believed to be induced by IFN gamma from T cells. Relatively few melanomas had (constitutive) PD-L1 expression in the absence of TILs.
Study and Results: In the present study we examined the signal pathways involved in inducible and constitutive expression of PD-L1 expression on cultured melanoma cells, including those derived from patients pre and post vemurafenib treatment. Our results suggest that nuclear factor kappa B (NF-kB) has a role in IFN-gamma inducible expression as shown by inhibition of PD-L1 expression with the inhibitor, BMS 345541 which blocks phosphorylation of the inhibitory IkB kinase, resulting in cytoplasmic retention of NF-kB p65 and p50 subunits. Luciferase based promoter reporter assays confirmed an association between NF-kB activity and PD-L1 expression levels. Targeting NF-kB was more effective in reducing inducible PD-L1 levels than targeting either the MAPK pathway or the P13Kinase/AKT pathway. Transfections with the super repressor, Inhibitor of kappa B alpha, mutated at S32 and S36, to correlate with PD-L1 levels are being carried out. In addition, si RNA mediated knockdown of the p50 and p65 subunits to confirm the involvement of NF-kB in PD-L1 expression will be studied. We are also currently dissecting the signaling pathways involved in constitutive expression of PD-L1.
NF-kB is an important protein complex involved in adaptive and innate immune response and regulates cytokine and chemokine production in melanoma. It also contributes to induction of proteins involved in cell proliferation and survival, playing a role in resistance to targeted therapy. The present results highlight another important function of this crucial transcription factor which our recent studies show may be targetable by inhibitors of the bromo domain and terminal repeat (BET) reader proteins.
Citation Format: Kavitha Gowrishankar, Dilini Gunatilake, Stuart Gallagher, Jessamy Tiffen, Peter Hersey. Regulation of PD-L1 expression in human melanoma by NF-kB. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2947. doi:10.1158/1538-7445.AM2014-2947
Abstract 295: Urine and serum biomarkers of pancreatic cancer
Authors: Nolen Brian M. , Grizzle William , Brand Randall , Lokshin Anna E. 
Published: May 2015

Abstract
The clinical management of pancreatic cancer is severely hampered by the absence of effective screening tools. Sixty seven candidate biomarkers were evaluated in prediagnostic sera obtained from cases of pancreatic cancer enrolled in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO). The multimarker panel of CA 19-9, OPN, and OPG, previously shown to be useful in retrospective samples, demonstrated markedly diminished performance in the PLCO cohort. CA 19-9, CEA, NSE, bHCG, and CEACAM1were significantly elevated in sera obtained from cases greater than 1 year prior to diagnosis. Levels of CA 19-9, CA 125, CEA, PRL, and IL-8 were negatively correlated with time to diagnosis. When the entire PLCO set was used for training at a specificity (SP) of 95%, a panel consisting of CA 19-9, CEA, and Cyfra 21-1 provided sensitivity (SN) levels of 33.3% in samples collected &gt;1 year prior to diagnosis compared to SN levels of 23.8% for CA 19-9 alone in the same sample sets. Further study performed using pooled PLCO samples identified 25 candidate biomarkers demonstrating significantly altered expression in pre-diagnostic serum samples. Robust performance of 3 of these biomarkers, GM-CSF, fibronectin, HCG, and SHBG was validated in individual PLCO samples. Next, performance of most promising serum biomarkers was assessed in case/control urine samples and in urine samples from a prospective Shanghai clinical trial. In each setup, better performance of urine biomarkers in comparison with serum counterparts was determined. A biomarker panel comprised of urine CA 19-9, leptin, OPN, and IL-8 had a SN=39% at a SP of 95% in Shanghai samples. These results warrant further studies to develop early detection tests for PDAC with high levels of sensitivity.
Note: This abstract was not presented at the meeting.
Citation Format: Brian M. Nolen, William Grizzle, Randall Brand, Anna E. Lokshin. Urine and serum biomarkers of pancreatic cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 295. doi:10.1158/1538-7445.AM2014-295
Abstract 2959: The tumor suppressor CHD5 is an epigenetic regulator of neuronal cell fate
Authors: Mills Alea A. , Hwang Dong-Woo 
Published: May 2015

Abstract
Genomic lesions affecting the 1p36 chromosomal region are prevalent in variety of human malignancies, yet the tumor suppressor in this region had not been identified. We used chromosome engineering to create a series of mouse models with lesions spanning the 1p36-analagous region. These gain and loss-of-function models allowed us to pinpoint a potent tumor suppressive interval that when deleted predisposes to cancer and when duplicated causes excessive tumor suppression. We identified Chromodomain Helicase DNA-binding domain protein 5 (CHD5) as the causative gene in the region, defined CHD5 as an inducer of the tumor suppressive network encoded at the Cdkn2 locus, and demonstrated that CHD5 is frequently deleted in human glioma. It is now appreciated that CHD5 is mutated in cancers of the breast, ovary, colon, and prostate, as well as in melanoma, glioma, and neuroblastoma, and furthermore, that robust CHD5 expression is a favorable indicator of patient survival following anti-cancer therapy.
Although ample evidence from human studies indicates that CHD5 plays a pivotal role in cancer, the mechanism responsible for tumor suppression is not well understood. CHD5 belongs to the CHD family of ATP-dependent chromatin remodeling proteins, yet CHD5's role in modulating chromatin and the consequence of CHD5 deficiency in vivo was unknown. We discovered that CHD5's tumor suppressive function is dependent on its dual plant homeodomains (PHDs)_motifs that bind specifically marked histones. The PHDs of CHD5 preferentially bind unmodified histone 3 (H3), an interaction essential for CHD5's ability to inhibit proliferation, to modulate transcription, and to suppress tumorigenesis in vivo. We recently defined CHD5 as a regulator of chromatin-mediated dynamics essential for neuronal differentiation. Whereas neural stem cells (NSCs) normally have the capacity to differentiate into neurons, NSCs from Chd5-deficient mice retain stem-like characteristics and differentiate into astrocytes at the expense of neurons. We discovered that H3K27me3_a repressive chromatin mark implicated in cancer_is depleted by CHD5 deficiency. We show that CHD5 rescues the de-differentiated phenotype of CHD5 deficient NSCs, while re-establishing global levels of H3K27me3.
Our findings define CHD5 as a dosage-sensitive tumor suppressor, identify CHD5 as a member of a newly appreciated class of H3-binding PHD-containing proteins, and reveal a critical role for CHD5 in dictating stem cell fate. This provides new insight into the epigenetic mechanisms responsible for CHD5's tumor suppressive role that when perturbed, set the stage for cancer.
Citation Format: Alea A. Mills, Dong-Woo Hwang. The tumor suppressor CHD5 is an epigenetic regulator of neuronal cell fate. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2959. doi:10.1158/1538-7445.AM2014-2959