bluuebunny/crossref_metadata_2025_split huggingface dataset:
Abstract A9: The cocaine and amphetamine-regulated transcript (CART) is an independent prognostic factor in lymph node-negative breast cancer and predicts outcome in tamoxifen treated patients
Authors: O'Connor Darran , Brennan Donal , Laursen Henriette , Bernards Rene , Crown John , Jirstrom Karin , Gallagher William 
Published: March 2013

Abstract
The successful identification and translation of informative biomarkers to aid clinical decision making is central to the effective implementation of personalized cancer therapeutic regimens. Antibody-based proteomics occupies a pivotal space in the cancer biomarker discovery and validation pipeline, facilitating the high-throughput evaluation of candidate markers. We have applied this approach to identify the cocaine- and amphetamine-regulated transcript (CART) as an independent poor prognostic marker in early stage breast cancer. The management of lymph node-negative breast cancer is the subject of much debate and two large ongoing clinical trials with particular emphasis on the requirement for adjuvant chemotherapy. Here we demonstrate, by tissue microarray and automated image analysis using a consistently applied threshold for definition of CART levels (median intensity +/− 1 standard deviation), that the neuropeptide hormone CART is expressed in primary and metastatic breast cancer and is an independent poor prognostic factor in ER-positive (p=0.0003), lymph node-negative (p=0.0025) tumors in two large breast cancer cohorts (n&gt;1000). Kaplan-Meier analysis and the log rank test were used to illustrate differences between overall survival (OS) and recurrence free survival (RFS) according to CART protein and mRNA expression. Cox regression proportional hazards models were used to estimate the relationship between outcome and CART expression, grade, age, nodal status, ER status, PR status, Her2, Ki-67 and tumor size. We also show that CART mediates an autocrine/paracrine effect leading to an amplification of the CART signal in breast cancer cells. Furthermore, we additionally demonstrate that CART increases the transcriptional activity of ERα in a ligand-independent manner via the mitogen-activated protein kinase (MAPK) pathway and that CART-High tumors express increased levels of ER-target genes. Finally, we show that ectopic expression of CART in two independent ER+ cell lines protects against tamoxifen-mediated cell death (p=0.025) and that high CART expression predicts outcome in 3 independent tamoxifen-treated cohorts (p=0.002). We clearly demonstrate that both pre- and postmenopausal patients with CART-positive tumors have a poor prognosis and are resistant to tamoxifen and therefore should receive aggressive adjuvant chemotherapy. We believe that CART profiling will facilitate stratification of lymph node-negative breast cancer patients into high- and low-risk categories and allow the personalization of therapy.
Abstract B15: The pan-BCR-ABL inhibitor ponatinib inhibits viability of gatekeeper mutant BCR-ABLT315I cells with greater potency than a nilotinib/MEK inhibitor combination
Authors: Schrock Alexa B. , Gozgit Joseph M. , Rivera Victor 
Published: March 2013

Abstract
Introduction: The second generation BCR-ABL inhibitor nilotinib has recently been shown to have weak off-target activity against RAF and drive the paradoxical activation of BRAF and CRAF in cells with activated RAS. Importantly, this effect has been seen in cells expressing T315I mutant BCR-ABL, against which nilotinib is ineffective (Packer, Cancer Cell 20:715). Interestingly, nilotinib was shown to synergize with an inhibitor of MEK, a downstream effector of RAF, to inhibit the viability of cells expressing BCR-ABLT315I. Ponatinib is a pan-BCR-ABL inhibitor that potently kills cells expressing BCR-ABLT315I and is in a pivotal phase 2 trial in patients with CML. Here we examined the activity of ponatinib against RAF and compared the cellular potency of ponatinib against BCR-ABLT315I to that of a nilotinib/MEK inhibitor combination.
Results: Ponatinib potently inhibited the in vitro kinase activity of ARAF, BRAF, and CRAF with IC50s of 71, 33, and 17 nM, respectively, compared to IC50s of 4390, 235, and 188 for nilotinib. In 2 RAS mutant cell lines tested, nilotinib (1 to 10 μM) induced feedback activation of RAF/MEK/ERK signaling as reported previously; however ponatinib (0.01 to 10 μM) did not. Both ponatinib and nilotinib potently inhibited viability of Ba/F3 cells expressing native BCR-ABL, with IC50s of 1.5 and 10 nM, respectively. While nilotinib has no activity against cells expressing BCR-ABLT315I, when combined with a concentration of the MEK inhibitor AZD6244 that inhibits MEK signaling (2 μM), nilotinib inhibited viability with an IC50 of 550 nM. In contrast, ponatinib potently inhibited viability of cells expressing BCR-ABLT315I with an IC50 of 6 nM. Similarly, single agent ponatinib induced apoptosis in BCR-ABLT315I cells with 100-fold greater potency than the combination of nilotinib and AZD6244.
Conclusion: In contrast to nilotinib, ponatinib does not appear to induce the paradoxical activation of RAF/MEK/ERK signaling in RAS mutant cells, possibly due to its inhibition of all 3 RAF family members. Although nilotinib synergizes with a MEK inhibitor to kill BCR-ABLT315I mutant cells, this effect requires a concentration of nilotinib approximately 50-fold higher than that required to kill native BCR-ABL cells. Substantially greater potency, at clinically achievable drug concentrations, is achieved via the direct inhibition of BCR-ABLT315I by ponatinib.
Abstract B2: Supplementation of dietary fish oil induces apoptosis through activation of PPARγ and involves inhibition of angiogenesis in colon cancer
Authors: Kansal Shevali , Negi Anjana K. , Agnihotri Navneet 
Published: March 2013

Abstract
Introduction: Eicosapentanoic acid (EPA) and docosahexaenoic acid (DHA), the n-3 polyunsaturated fatty acids (PUFAs) enriched in fish oil, reduces proliferation and enhances apoptosis relative to n-6 PUFA treated cells. PPARγ, a member of retinoid X receptors (RXR) family, is implicated in the control of cell proliferation and apoptosis. One of the important components of Wnt pathway, β-catenin is also involved in cell proliferation. Hence, the present study was designed to understand the mechanism of action of different ratios of fish oil (FO) and corn oil (CO) in experimentally induced colon carcinoma by estimating the expression of PPARγ, apoptosis, β-catenin and VEGF.
Methods: Male wistar rats were divided into following groups-
Group I received purified diet while Group II and Group III received modified diet with FO:CO(1:1) and FO:CO(2.5:1) respectively for 4 weeks. After one week of purified diet, all the 3 groups were divided into two subgroups- one received the injection of ethylenediamine-tetra acetic acid intraperitoneally and another received dimethylhydrazine dihydrochloride (DMH) per week for 4 weeks (20mg/kg body weight). The animals which were killed 48 hours after the last injection constituted initiation phase whereas the remaining were kept on standard pellet diet and sacrificed on completion of 16 weeks constituted post initiation phase. The effect of different ratios of FO:CO was analyzed by estimating the expression of PPARγ in colonocytes; apoptotic/ necrotic cells by immunofluorescence; expression of β-catenin and VEGF by immunohistochemistry.
Results: DMH administered animals have shown:
No significant alteration in the expression of PPARγ in initiation phase whereas the expression was decreased significantly (p&lt;0.001) in post-initiation phase.Apoptotic cells were increased significant (p&lt;0.01) in the initiation phase whereas apoptotic cells were decreased significant in post-initiation phase (p&lt;0.001).An increased expression of β-catenin and VEGF in both the phases.
In comparison to DMH treated animals, treatment with different ratios of FO and CO have shown:
A significant (p&lt;0.001) increase in the expression of PPARγ in both the phases. However, the increase was more pronounced with FO+CO(2.5:1).A significant increase in apoptotic cells in both the phases. On treatment with FO+CO(2.5:1), cells undergoing necrosis were significantly increased as compared to FO+CO(1:1).The expression of β-catenin and VEGF were decreased in both the phases with both the ratios.
Conclusion: The dose and time dependent chemopreventive effect of FO and CO may be mediated by increasing the expression of PPARγ, apoptosis and by inhibiting β-catenin and VEGF.
Abstract B22: Re-expression of miR-200 by natural agents regulates the expression of PTEN and MT1-MMP in pancreatic cancer
Authors: Ali Shadan , Soubani Omar , Ali Azfur , Logna Farah , Philip Philip , Sarkar Fazlul 
Published: March 2013

Abstract
Purpose: Membrane type-1 matrix metalloproteinase (MT1-MMP) is often activated and expressed in tumor cells with significant invasive properties, and is associated with poor prognosis of patients. This could partly be due to deregulated expression of microRNAs (miRNAs) which regulates the expression of MT1-MMP and PTEN (Phosphatase and tensin homolog) contributing to tumor invasion and metastasis.
Experimental Procedure: We initially compared the expression profile of miR-200 family, PTEN and MT1-MMP expression in six pancreatic cancer (PC) cell lines by qRT-PCR and western blot analysis. Based on our initial findings, we chose BxPC-3, MIAPaCa-2, and MIAPaCa-2-GR cells for further mechanistic studies. We assessed the effect of two separate novel agents CDF, (a synthetic analogue of curcumin) and BR-DIM (a natural agent) on PC cells.
Results: We found loss of expression of miR-200a, b, and c in chemo-resistant PC cell lines, which was correlated with loss of PTEN and over-expression of MT1-MMP. The expression of miR-200 family and PTEN was significantly re-expressed whereas the expression of MT1-MMP was down-regulated by CDF and BR-DIM treatment. Forced over-expression or silencing of miR-200c, followed by either CDF or BR-DIM treatment of MIAPaCa-2 cells altered the morphology of cells, wound-healing capacity, colony formation, and the expression of MT1-MMP and PTEN.
Conclusion: These results provide strong experimental evidence showing that the loss of miR-200 family and PTEN expression, and increased level of MT1-MMP leads to aggressive behavior of PC cells, which could be attenuated through re-expression of miR-200c by CDF and/or BR-DIM treatment, suggesting that these agents could be useful for treatment.
Abstract B37: Monitoring kinome response to EGFR inhibition in triple negative breast cancer
Authors: Whittle Martin C. , Duncan James S. , Graves Lee M. , Johnson Gary L. 
Published: March 2013

Abstract
Triple negative breast cancers (TNBC) are resistant to hormone therapies and HER2-targeted therapies because of their ER-negative, PR-negative, and HER2-negative status. A further lack of molecularly targeted therapies for TNBC leaves conventional cytotoxic chemotherapy as the primary course of treatment for basal-like TNBC. While TNBCs are initially sensitive to chemotherapy, resistance can quickly develop, and tumors often recur with an aggressive metastatic phenotype and poorer patient prognosis. Expression of EGFR has been linked to basal-like TNBC, and EGFR expression is significantly associated with poorer prognosis in patients. However, clinical trials targeting EGFR in TNBC have been largely unsuccessful, possibly due to TNBC cell responses that bypass targeted inhibition of EGFR. Thus, EGFR inhibition in TNBC may cause a rewiring of kinase signaling, allowing TNBC cells to evade growth arrest and/or apoptosis. Rational design of combination therapies for treating cancer entails knowing how cancer cells rewire kinase growth signaling pathways to promote proliferation and survival in the presence of molecularly targeted therapies. In this study we applied a chemical proteomic approach to define kinome response to EGFR inhibitor treatment in TNBC and identify kinases upregulated in response to EGFR inhibition. We discovered compensatory upregulation of multiple receptor tyrosine kinases in response to EGFR inhibitors that may be mediating cell growth and survival following EGFR inhibition. Our methods show that kinome response to drug treatment can be monitored and proposes a new mode for designing effective small molecule inhibitor combinations for treating cancer.
Abstract B43: Alisertib (MLN8237), an Aurora Kinase A inhibitor, enhances Docetaxel-induced cell death in Upper Gastrointestinal Adenocarcinoma cells
Authors: Sehdev Vikas , Revetta Frank , Belkhiri Abbes , Ecsedy Jeffrey , Zaika Alexander , El-Rifai Wael 
Published: March 2013

Abstract
Upper gastrointestinal adenocarcinomas (UGCs) respond poorly to current chemotherapeutic regimes. We and others have previously reported frequent AURKA gene amplification and mRNA and protein overexpression in UGCs. It has been shown that AURKA can induce chemotherapeutic resistance and regulate several key signaling pathways in cancer cells, suggesting its role as a central node in cancer cell signaling. The DCF (docetaxel, cisplatin and 5-FU) regimen is the most promising chemotherapeutic regimen against UGC. However, AURKA overexpression can mediate resistance to both Taxol and cisplatin. These findings provide a credible rationale for targeting AURKA. In this study we have reported therapeutic response of the recently developed AURKA selective inhibitor MLN8237 as a single agent and in combination with docetaxel. Our findings provide a foundation for a promising new approach of future targeted therapy in UGCs. Using AGS, FLO-1 and OE33 UGC cell lines, with constitutive AURKA overexpression and variable-p53 status, we observed inhibition of cancer cell survival with 0.5μM MLN8237 (p&lt;0.05) alone. This effect was significantly enhanced in combination with 1.0nM docetaxel (p&lt;0.001). Cell cycle analyses after 48hr of treatment with MLN8237 demonstrated a significant increase in the percentage of polyploidy for AGS and OE33 UGC cells (p&lt;0.01) which was further enhanced by docetaxel (p&lt;0.001). Additionally, an increase in the percentage of cells in the sub-G1-phase at 24hrs and 48hrs was observed with MLN8237 in FLO-1 (p&lt;0.01) cells which was significantly enhanced with MLN8237 and docetaxel combination (p&lt;0.001). Western blot analysis demonstrated higher induction of cleaved caspase 3 and cleaved PARP with the combined treatment, as compared to a single agent treatment. Using xenograft models, we demonstrated an enhanced anti-tumor role for the MLN8237 and docetaxel combination, as compared to single agent treatments (p&lt;0.001). In conclusion, this study demonstrates that MLN8237, combined with docetaxel, can mediate a better therapeutic outcome in UGCs.
Abstract B45: Met-Dependent Positive and Negative Signaling Cascades in Gastric Cancer Cells
Authors: Lai Andrea Z. , Cory Sean , Zhao Hong , Bell Emily S. , Hallett Michael , Park Morag 
Published: March 2013

Abstract
Signaling by the Met, hepatocyte growth factor (HGF) receptor tyrosine kinase (RTK) activates multiple downstream signaling pathways that promote cell migration and invasive growth. Cells that overexpress and are “addicted” to Met also require Met signaling to sustain cell survival. Thus, a number of specific small-molecule inhibitors have been developed to target Met in the clinic. Although several successes of RTK-targeted therapies are acknowledged, several have limited long-term success clinically, due to development of drug resistance.
Initiation of RTK signaling cascades leads to the activation of a number of downstream signaling molecules, but prolonged activation also triggers negative feedback loops that function in part to abrogate this signaling. Hence, targeted inhibition of Met, in addition to suppressing Met-dependent signaling, may also release cells from negative feedback mechanisms and allow the reactivation of signaling pathways that may promote resistance to Met inhibition.
As MET amplification occurs in 20–40% of gastric cancers, to identify core Met dependent signaling pathways activated in Met dependent cancers we have used four different gastric cancer cell lines that exhibit amplification, overexpression, and constitutive activation of Met. Upon inhibition of Met with a small-molecule inhibitor, we observe abrogation of several downstream signaling pathways at both the protein phosphorylation and transcript level. Interestingly, as Met has been demonstrated to cross-talk with the EGF receptor family, we also observe a decrease in the phosphorylation of EGFR and HER3 upon treatment with Met inhibitor, and a decrease in expression of EGFR ligands. Conversely, Met inhibition results in an elevation in expression of HER3 transcript and protein in all 4 cell lines, implicating Met signaling in HER3 repression, and inhibition of Met may release HER3 from this negative regulation. As increases in HER3 phosphorylation and expression occur in other models (such as breast or lung cancer cell lines) upon treatment with EGFR, HER2, or AKT inhibitors, and high HER3 expression is strongly associated with tumor progression and poor prognosis in gastric cancer; hence, the loss of negative regulation of HER3, downstream from Met, may ultimately contribute to clinical efficacy, or lack thereof, of Met inhibitors.
Abstract B5: CpG-siRNA conjugates: Overcoming cancer immunoresistance
Authors: Nechaev Sergey , Zhang Qifang , Swiderski Piotr , Kortylewski Marcin 
Published: March 2013

Abstract
Small interfering RNA (siRNA) have been proved to be an effective tool for treating diseases caused by gene expression abnormalities. However, clinical relevance of siRNA technology is compromised by multiple obstacles, such as lack of cellular specificity, low efficiency of cellular uptake and/or poor cytoplasmic release. We have previously demonstrated that natural capability of certain immune cells to recognize non-methylated CpG motifs in DNA oligonucleotides can be harnessed for cell-specific siRNA delivery. The siRNA molecules conjugated to CpG oligonucleotides (CpG-siRNA) are efficiently internalized and bind to the intracellular Toll-like receptor 9 (TLR9) in human and mouse dendritic cells as well as in certain TLR9-positive tumor cells. We designed a CpG-siRNA targeting Stat3 (signal transducer and activator of transcription-3), a transcription factor, which is constitutively activated in majority of mouse and human cancers. Oncogenic Stat3 signaling regulates cancer cell proliferation, survival and promotes tumor immunoresistance. We have previously shown that CpG-Stat3 siRNA can eliminate Stat3 signaling in tumor-infiltrating myeloid cells, resulting in potent antitumor immunity. In the current study, we investigated the intracellular mechanism of action of CpG-siRNA conjugates. We have demonstrated that internalized CpG-siRNAs are recruited into endosomes by dynamin-dependent mechanism and bind to endosomal TLR9 receptor. Further events include uncoupling of siRNA from the CpG moiety by Dicer endonuclease, and rapid translocation of siRNA to endoplasmic reticulum for recruitment into functional RISC (RNA interference silencing complex). We confirmed the target gene silencing both in vitro and in vivo, and proved that it occurs through RNA interference mechanism. Our current results indicate that downstream effectors of TLR9 pathway may be involved in RISC assembly and/or activation. Overall, the CpG-siRNA strategy provides a novel opportunity for overcoming cancer immunoresistance with translational potential for therapy of various malignancies.
Abstract B53: Proteasome inhibitor MG132 induces NAG-1 expression through activation of p38 MAPK pathway
Authors: Shimizu Sachie , Kinyamu Harriet , Yoshioka Hiroki , Kadowaki Mitsutoshi , Watanabe Takashi , Eling Thomas 
Published: March 2013

Abstract
Glioblastoma multiforme (GBM) is the highly invasive primary tumors with a poor prognosis despite current surgical, radiation and chemotherapy approaches. Proteasome inhibitor, an approved drug for treatment of hematological cancer is currently being tested in clinical trials against various malignancies, including GBM. The pro-apoptotic and antitumorigenic protein NAG-1(nonsteroidal anti-inflammatory drug-activated gene-1) is a divergent member of the transforming growth factor-beta (TGF-beta) superfamily. We showed that the proteasome inhibitor, MG132 induces NAG-1 protein and mRNA expression and apoptosis in a concentration-dependent manner in U87 cells. Studies with NAG-1 luciferase reporter constructs show that the −133 to +41 region of the NAG-1 promoter is activated by MG132 however activation does not require the Sp-/Egr-1 binding site. Using the selective pharmacologic p38 mitogen -activated protein kinase (MAPK) inhibitor, we showed that NAG-1 induction following MG132 is mediated by the p38 MAPK pathway. Pretreatment with MAPK inhibitor, SB203580 and SB202190, blocked the MG132-induced NAG-1 expression, whereas an inhibition of p53, JUNK, MEK, PKC, PKA activity had no effect on NAG-1 levels. In summary, our data indicate linkage between p38MAPK, NAG-1 and the proteasome inhibitor, MG132 and provides a new clue to the molecular mechanism of the antitumorigenic activity of NAG-1.
Abstract B8: FOXD3 enhances expression of ERBB3 and promotes resistance to vemurafenib
Authors: Basile Kevin J. , Abel Ethan V. , Aplin Andrew E. 
Published: March 2013

Abstract
Melanoma cells driven by mutant B-RAF are sensitive to vemurafenib (PLX4032), which selectively inhibits BRAF/MEK/ERK1/2 signaling. Despite initial tumor shrinkage, most responders in the trials experienced tumor relapse over time. Furthermore, approximately 5–15% of patients show tumor progression. These findings indicate that resistance mechanisms will hamper the clinical efficacy of vemurafenib. We have previously shown that a stemness factor, FOXD3, is upregulated following inhibition of B-RAF-MEK signaling in mutant B-RAF melanoma cells. Here, we show that siRNA-mediated knockdown of FOXD3 significantly enhanced the cell death response after PLX4032 treatment in mutant B-RAF melanoma cell lines. Additionally, ectopic expression of FOXD3 in nonadherent cells significantly reduced cell death in response to PLX4720 treatment. Genome wide analyses revealed that FOXD3 significantly increased expression of ERBB3 through direct binding to a known enhancer region of the ERBB3 gene. Knockdown of endogenous FOXD3 reduced ERBB3 upregulation after treatment with PLX4032. Furthermore, activation of ERBB3 in the presence of ligand was enhanced by B-RAF inhibition in an ERBB2-dependent manner. Treatment with the EGFR/ERBB2 inhibitor, lapatinib, in combination with PLX4032/4720 significantly reduced viability in both in vitro and in vivo assays. These data indicate that upregulation of FOXD3 is an adaptive response to B-RAF inhibitors that enhances ERBB3 signaling and promotes a state of drug resistance.