bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 1879: The exomes of the NCI60 and their implications for cancer pharmacogenomics
Authors: Abaan Ogan D. , Davis Sean R. , Bilke Sven , Polley Eric C. , Walker Robert L. , Pineda Marbin , Zhu Yuelin J. , Reinhold William , Holbeck Susan L. , Simon Richard M. , Doroshow James H. , Pommier Yves , Meltzer Paul S.
Published: August 2012

Acquired and constitutional genetic variations in cancers have a substantial influence on response to therapy. The NCI60 panel of cell lines provides a unique opportunity to investigate this problem. These 60 human tumor cell lines represent 9 cancer types, and are richly characterized as the result of many previous studies which have collected various biochemical and genomics data [1]. In addition, there exists a comprehensive dataset of sensitivity and resistance profiles of over 100,000 compounds with potential antineoplastic activity. However, characterization of coding region DNA sequence variants has been lacking. In this study, we sequenced the whole exomes of the NCI60 cell lines and identified single nucleotide variants and short insertions/deletions. Variants found by sequencing were in excellent agreement with variants previously identified by SNP analysis or targeted capillary sequencing. Even though most cell lines displayed similar mutation counts, cell lines with microsatellite instability displayed a hypermutator phenotype. In addition, observation from ti/tv ratio and nature of base changes revealed preservation of possible carcinogen specific DNA mutation signatures. Deleterious variants were identified at higher frequency in known cancer genes while TP53 mutations where the most frequent event among the NCI60. Finally, notable instances of correlation between gene/pathway mutations with sensitivity to certain drug/compounds was identified. For example, sensitivity to vemurafenib was highly correlated with BRAF mutation. This comprehensive dataset enhances the value of cell lines widely used as disease models in many laboratories by adding depth to the existing genomic data. Our analysis identifies a large number of genomic variants correlated with drug responsiveness, including a number of genes known to be targeted by specific agents as well as numerous candidates for future investigation. 1. Shankavaram, U.T., et al., CellMiner: a relational database and query tool for the NCI-60 cancer cell lines. BMC Genomics, 2009. 10: p. 277.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1879. doi:1538-7445.AM2012-1879
Abstract 1892: Identification of differentially methylated genes associated with cetuximab and erlotinib resistance
Authors: Ogawa Takenori , Chang Xiaofei , Koch Wayne , Sidransky David
Published: August 2012

Anti-EGFR therapy is among the most promising molecular targeted therapies against cancer developed in the past decade. Two classes of EGFR-directed therapeutic inhibitors are currently in clinical use: anti-EGFR monoclonal antibodies, such as cetuximab, and small-molecule tyrosine kinase inhibitors (TKIs) of EGFR, such as erlotinib. Although both classes of drugs are capable of inducing an initial therapeutic response, primary as well as acquired drug resistance is frequently observed. Emerging evidence has linked epigenetic changes, such as DNA methylation at CpG islands, to the development of cytotoxic chemotherapeutic drug resistance. To identify genes that are specifically methylated during the evolution of resistance to anti-EGFR therapeutic agents, we employed two parental NSCLC and HNSCC cell lines and their resistant derivatives to either erlotinib or cetuximab. DNA from each pair was used for methylation-specific array containing a panel of 64 genes that are commonly known to be regulated through promoter methylation. We found that death-associated protein kinase 1 (DAPK1) was hypermethylated in drug resistant cells generated from both parental cell lines. Restoration of DAPK1 into the resistant cells by stable transfection re-sensitized the cells to both erlotinib and cetuximab. Conversely, siRNA-mediated knockdown of DAPK1 induced resistance in the parental sensitive cells. These results demonstrate that DAPK1 plays an important role in both cetuximab and erlotinib resistance in NSCLC and HNSCC cancer cells, and that promoter methylation of its gene frequently occurs during the chronic treatment of anti-EGFR agents. In conclusion, DAPK1 could be a novel target for the improvement of therapeutic benefit of anti-EGFR therapy.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1892. doi:1538-7445.AM2012-1892
Abstract 1904: Transforming growth factor-beta mediated epithelial to mesenchymal transition contributes to in vivo resistance to sorafenib in hepatocellular carcinoma
Authors: Lin Shiou-Der , Lin Tzu-Hsuan , Feng Wen-Chi , Shao Yu-Yun , Cheng Ann-Lii , Hsu Chih-Hung
Published: August 2012

Sorafenib, a multikinase inhibitor targeting Raf kinase and vascular endothelial growth factor receptor, is currently the only approved agent for hepatocellular carcinoma (HCC). However, the majority of HCC patients are inherently resistant to sorafenib treatment. To study molecular mechanisms underlying the resistance to sorafenib in vivo, we studied immunocompromised mice implanted with xenografts of human HCC cells subcutaneously, and identified tumors that showed primary resistance to sorafenib. Primary cultured cells were established from sorafenib-resistant xenografts, and verified for in vitro and in vivo sensitivity to sorafenib. The differentially expressed genes of the resistant cells versus control cells were analyzed by cDNA microarray. The expressions of candidate markers were confirmed by Western blotting, and their significances were verified by specific pathway inhibitors. A subline of Huh7 cells was established by primary culture from a sorafenib-resistant HCC-xenograft (designated as Huh7.1.SR). Compared to Huh7 cells primarily cultured from HCC-xenograft treated with vehicle alone (designated as Huh7.1.v), Huh7.1.SR had a moderate increase of resistance to sorafenib in vitro, with 50%-inhibitory concentration (IC50) increased from 5 to 10 μM. Subcutaneous xenograft studies confirmed that Huh7.1.SR retained the phenotype of in vivo resistance to sorafenib. The IPA (ingenuity pathway analysis) of differentially expressed genes of Huh7.1.SR versus Huh7.1.v cells revealed several pathway networks centering at transforming growth factor beta receptor (TGFBR), hepatocyte nuclear factors, NOTCH, pro-inflammatory cytokines, and nuclear factor kappa B. Huh7.1.SR had an increased expression of TGF-beta and p-Smad2, indicating that the TGF-beta pathway was activated. Huh7.1.SR cells expressed phenotypic features of epithelial to mesenchymal transition (EMT), including higher expression of vimentin, lower expression of E-cadherin, and increased cell migration. The expressions of Slug and Twist, two well-known transcriptional factors of inducing EMT, also increased in Huh7.1.SR cells. Treatment of SD-208, an inhibitor of TGF-beta receptor, partially reversed the phenotypic features of EMT in Huh7.1.SR cells. Moreover, concomitant treatment of SD-208 improved the sensitivity to sorafenib in Huh7.1.SR cells. Our data indicate that activation of TGF-beta signaling pathway is an important mechanism mediating the resistance to sorafenib in HCC in vivo. (The study was supported by the grant NSC 100-2325-B-002-043- from National Science Council of Taiwan)

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1904. doi:1538-7445.AM2012-1904
Abstract 1909: Cytoprotective autophagy is involved in resistance towards MET inhibitors in human gastric adenocarcinoma cells
Authors: Humbert Magali , Medová Michaela , Aebersold Daniel M. , Tschan Mario P. , Zimmer Yitzhak
Published: August 2012

MET, also known as hepatocyte growth factor receptor, is a receptor tyrosine kinase (RTK) that plays an important role both in normal cellular function as well as in oncogenesis. In many different cancer types, abnormal activation of MET is related to poor prognosis and various strategies to inhibit its function, including small molecule inhibitors, are currently in preclinical and clinical evaluation. Although promising results have been obtained with a variety of different MET RTK inhibitors, different resistance mechanisms were found. We hypothesized that autophagy, a self-digesting recycling mechanism for cellular organelles and macromolecules with cytoprotective functions, might be involved in resistance towards MET inhibitors. Autophagy induced upon MET inhibition might support cancer cell survival. We therefore aimed at investigating the involvement of autophagy upon MET inhibition in GTL-16 gastric adenocarcinoma cells. First, we treated GTL-16 cells with the MET inhibitor PHA665752. We observed a marked induction of autophagy in these cells upon MET inhibition as measured by LC3I/LC3II conversion and GFP-LC3 dot formation. Similar results were seen in another gastric adenocarcinoma cell line, namely MKN-45. Next, to investigate if MET inhibition-mediated induction of autophagy is a protective mechanism, we treated GTL-16 cells with PHA665752 in combination with compounds that influence autophagic activity. Interestingly, a combination treatment of MET and autophagy inhibitors (3-Methyladenine, 3-MA) significantly (MWU, p<0.001) decreased cell viability as determined by an MTT assay. In contrast, using the autophagy activator lithium chloride in combination with MET inhibitors, cell viability was significantly increased (p<0.01). All data were confirmed using a second MET-inhibitor. To exclude that 3-MA autophagy independent functions account for the increased cell death during treatment with PHA665752, we inhibited autophagy by knocking down the key autophagy gene ATG7 in GTL-16 cells using lentiviral vectors expression small hairpin (sh)RNA targeting ATG7. These “autophagy knockdown” GTL-16 cells displayed a significant increase in cell death upon MET inhibition as compared to GTL-16 control cells expressing a scrambled control shRNA. In conclusion, our results point to a cytoprotective function of autophagy in response to MET inhibition. The use of MET in combination with autophagy inhibitors may represent a novel therapeutic option for the treatment of gastric carcinoma with aberrant MET activity.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1909. doi:1538-7445.AM2012-1909
Abstract 1921: A novel FAK kinase inhibitor (PF-4554878) decreases growth and induces apoptosis in pancreatic neuroendocrine tumor cells
Authors: Francois Rony , Lu Shun , He Di-Hua , Zajac-Kaye Maria , Hochwald Steven N.
Published: August 2012

Introduction: Pancreatic neuroendocrine tumors (PNETs) are poorly understood and there are few effective therapies. Focal adhesion kinase (FAK) is an important tyrosine kinase implicated in cell survival signaling and found to be overexpressed in many malignancies. Our hypotheses are that 1) FAK expression is upregulated, 2) that FAK plays an important role in PNET cell survival, and 3) that a novel ATP competitive kinase inhibitor of FAK demonstrates anti-neoplastic efficacy in PNET cells. Methods: By Western blot, the expression of FAK was determined in frozen human PNETs compared to normal human pancreas. The compound, PF-4554878 (Pfizer), has been shown to be an ATP competitive kinase inhibitor of FAK. The in-vitro effects of this compound on cell signaling, viability and apoptosis in human pancreatic neuroendocrine cells (BON-1 and QGP-1) were evaluated. Statistical analysis was performed via t-test with significance defined as p<0.05. Results: FAK was found to be overexpressed in PNETs compared to normal pancreas. PF-4554878 not only caused a decrease in PNET cell viability with an IC50 of 5 µM in human pancreatic neuroendocrine cell lines, but also caused a statistically significant dose-dependent increase in apoptosis by TUNEL staining and/or PARP cleavage. These effects were associated with a decrease in Y397 phosphorylation of FAK. Conclusions: A novel compound that inhibits the kinase activity of FAK results in decreased PNET proliferation and induction of apoptosis. These effects appear to be mediated through downregulation of p-FAK (Y397). This compound deserves further study as a novel treatment strategy in human PNETs.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1921. doi:1538-7445.AM2012-1921
Abstract 1931: A potential antitumor herb medicine, Corilagin, inhibits ovarian cancer cell growth by blockage of TGF-β/AKT/ERK signaling pathways
Authors: Jia Luoqi , Jin Hongyan , Zhou Jiayi , Chen Lianghua , Lu Yiling , Ming Yanling , Yu Yinhua
Published: August 2012

Recently, we have identified that Corilagin is a major anti-tumor active component extracted from a well-known hepatoprotective and antiviral medicinal herb, Phyllanthus niruri L. Corilagin distinctly inhibited the growth of ovarian cancer cell lines SKOv3ip, Hey and HO-8910PM, with IC50s less than 20µg/ml, while displayed the low toxicity against normal ovarian surface epithelium (OSE), with IC50s around 100µg/ml. Corilagin induced cell cycle arrest at G2 stage and enhanced apoptosis in Hey cancer cells. To explore its anti-tumor activity in vivo, Corilagin was delivered intra-peritoneally to the mice bearing SKOv3ip xenograft. Although no statistical difference observed on mice weight between untreated and Corilagin treated groups, xenograft tumor growth was significantly restarted by 15µg/mL of Corilagin treated group comparing to untreated control group (p<0.05). To understand the anti-tumor mechanisms of Corilagin, we performed reverse phase protein array (RPPA) analysis using untreated and Corilagen treated HO-8910PM cells, and the results were confirmed by Western blots. We have found that Corilagin blocked the activation of multiple signaling cascades, such as, pAKT and pERK. Particularly, Corilagin inhibits TGF-β secretion in the culture supernatant of all tested ovarian cancer cell lines and blocks the stabilization of Snail induced by TGF-β in HO-8910PM cells. In contrast, reduction of TGF-β secretion was not observed in cytotoxic drug Taxol-treated cancer cells, suggesting that Corilagin specifically targets TGF-β secretion. TGF-β signaling plays a critical role in epithelial-mesenchymal transition (EMT) and cancer metastasis. High concentration of TGF-β had been detected in ascites, blood and other body fluids of ovarian cancer patients. In addition, our recent studies identified that TGF-β being the most important inflammation factor in ovarian cancer, which stabilizes at the protein level of Snail, an inducer of EMT, and further enhanced Snail expression when combined with other inflammation factors. TGF-β is regulated by Smads, but could also be regulated by AKT/ERK signaling pathways. Our observations indicate that Corilagin extracted from Phyllanthus niruri L. acts as an effective natural targeted therapeutic agent against the growth of ovarian cancer cells via TGF-β/AKT/ERK signaling pathways.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1931. doi:1538-7445.AM2012-1931
Abstract 1934: Characterization of the anti-proliferative effect of 6-(3-aminopropyl)-9-methoxy-3-nitro-5H-indeno[1,2-c]isoquinoline-5,11(6H)-dione in cultured PC-3 cells
Authors: Park Eun-Jung , Morrell Andrew , Conda-Sheridan Martin , Cushman Mark , Pezzuto John M.
Published: August 2012

Previously, we reported interesting pharmacological responses mediated with indenoisoquinolines, including cytotoxic effects mediated by the topoisomerase I inhibitor 6-(3-aminopropyl)-9-methoxy-3-nitro-5H-indeno[1,2-c]isoquinoline-5,11(6H)-dione (AM9-79). We currently describe further mechanistic evaluations performed with cultured PC-3 cells. AM9-79 strongly inhibited proliferation in a dose- and time-dependent manner (IC50 = 9.77 nM; 72 h incubation period). As indicated by Annexin V/7-AAD double staining, an elevated population of cells was undergoing apoptosis. Accordingly, cellular levels of pro-apoptotic proteins such as Bcl-2 were decreased, and the protein cleavage and enzymatic activities of several caspases, which play pivotal roles in apoptosis, were induced. Effects on gene expression were evaluated with a cDNA microarray, and it was found that AM9-79 significantly up-regulated the expression of BRCA2, CDKN1A, GADD45A, SERTAD1, and TP53. Consistent with these results, the protein level of CDKN1A (p21WAF1/CIP1), and phosphorylation/activation of ERK1/2, a signaling molecule positively correlated to the expression of BRCA2, were up-regulated. Further investigation of a potential upstream mechanism revealed treatment with AM9-79 decreased the protein level of EGFR and reduced nuclear translocation. This is relevant since current evidence indicates EGFR functions not only as a transmembrane receptor but also as a transcriptional factor. In accord with this response, decreased expression levels of downstream molecules (iNOS and cyclin D1) were observed. In sum, these data suggest AM9-79 can effectively function by novel mechanisms of relevance for the treatment or prevention of cancer. (Supported by P01 CA48112 awarded by the NCI)

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1934. doi:1538-7445.AM2012-1934
Abstract 1945: A novel self assembled taxane nanoparticles for breast cancer chemotherapy
Authors: Kulkarni Ashish A. , Soh Hua Xiang , Sengupta Poulomi , Basu Sudipta , Sengupta Shiladitya
Published: August 2012

Breast cancer is the most frequently diagnosed form of cancer and a second leading cause of cancer deaths among women in the United States, with an estimated 207,090 new cases and 39,840 deaths since the beginning of 2010. Taxane-based chemotherapeutic agents are extensively used as a treatment for breast cancer and have shown important clinical benefits in both adjuvant and metastatic settings. However, the therapeutic efficacy of these drugs is hampered by limitations such as poor water solubility, narrow therapeutic indices and significant off-target toxicities which limit its dose escalations and treatment frequency. Also, current drug delivery strategies often suffer from constraints such as lower potency, low loading, non-biocompatibility/ non-biodegradability and uncontrolled release of the drug. Clearly, there is an urgent need for a paradigm shift in the strategies for the development of drug delivery vehicles for breast cancer management. We propose a novel approach in the design of nanomedicine where an active molecule can self-assemble into a nanoparticle resulting in increased loading, improved antitumor outcome and reduced off-target side effects. Different taxane analogs were attached to cholesterol using an acid labile linker. The self assembly of taxane-cholesterol conjugate was facilitated by phosphatidylcholine and DSPE-PEG to form well defined nano-sized particles. The loading of 10-15 μg/μL of drugs was obtained and sustained release of drugs was observed at pH 5.5 over 48h. In a preliminary cell viability studies, the taxane nanoparticles showed comparable efficacy to drug alone. Next, in order to achieve tumor specific homing of the nanoparticles, we plan to incorporate multiple copies of iRGD peptide on the nanoparticle surface that will bind to αvβ3 integrins overexpressed on the endothelium of tumor vessels and help in effective internalization of nanoparticles. The optimum density of peptides on the nanoparticle surface will be achieved by conjugating the peptide to DSPE-PEG. We believe that this study will not only uncover a novel and most effective nanotechnology-based approach for breast cancer treatment but will also eventually lead to an improvement in the quality of life of patients at minimum cost.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1945. doi:1538-7445.AM2012-1945
Abstract 195: The tumor cell compartment holds the unfavorable prognostic value of miR-21 in gliomas
Authors: Hermansen Simon K. , Dahlrot Rikke H. , Nielsen Boye S. , Hansen Steinbjørn , Kristensen Bjarne W.
Published: August 2012

High-grade gliomas are some of the most lethal forms of human cancer and new clinical biomarkers and therapeutic targets are highly needed. MicroRNAs (miRNAs), a group of short noncoding RNAs, hold great potential as new biomarkers and targets as they are commonly deregulated in a variety of diseases including gliomas. MicroRNA-21 (miR-21) is the most consistently over-expressed miRNA in several cancers including gliomas and is therefore very promising as a useful clinical biomarker and therapeutic target. To better understand the role of miR-21 in gliomas, paraffin embedded glioma tissue samples from 193 patients with grade I, II, III and IV tumors were analyzed by in situ hybridization (ISH) using LNA-DNA chimeric probes. We found miR-21 expression in tumor cells and tumor-associated blood vessels, whereas no expression was seen in adjacent normal brain parenchyma. Using advanced image analysis we obtained quantitative estimates reflecting the miR-21 expression levels. The miR-21 levels correlated significantly with grade (p = 0.027, rs = 0.161, 95% CI, 0.015 to 0.301) with the highest levels measured in grade IV gliomas. Furthermore, quantitative estimates obtained for the tumor cells alone were significantly associated with poor prognosis in all tumors (p = 0.012) and grade III and IV tumors alone (p = 0.005). This was independent of known clinical parameters (age, grade and sex). In conclusion, we have shown that miR-21 is constricted to tumor cells and tumor blood vessels and that tumor cell miR-21 represent a valuable prognostic biomarker for the disease.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 195. doi:1538-7445.AM2012-195
Abstract 1964: Development of a nanovaccine for cancer therapy
Authors: Bright Vanessa R. , Gilchuk Pavlo , Gordy Laura , Flyak Andrew , Joyce Sebastian , Yankeelov Thomas , Pham Wellington
Published: August 2012

Purpose: Despite significant advancements in dendritic cell (DC)-based cancer immunotherapy, the approach remains challenging, especially with regard to developing a simple yet robust method for activating the immune system against cancer in the context of using tumor antigen-activated DCs. To improve the feasibility of this immunotherapy approach, we sought to develop a robust vaccine that utilizes nanotechnology to activate endogenous DCs in the host. Method: Using a superparamagnetic iron oxide (SPIO) nanoparticle as the carrier for this therapy, two immune system activating molecules were conjugated to the nanoparticle. The dextran-coated SPIO nanoparticles were reacted with an epoxyamine linker to produce amine groups on the surface of the nanoparticle. Next, a potent Natural Killer T (NKT) cell activating glycolipid, was conjugated to the SPIO nanoparticle via a disulfide-containing crosslinker. For in vivo studies, an MUC-1 derived antigenic peptide was conjugated as well to the same nanoparticles. Here, adult MUC-1 transgenic C57BL/6 mice were implanted with MUC-1 transfected C57G tumors. The protein and adjuvant conjugated nanoparticle was delivered to mice via subcutaneous injection. Tumor growth in the treated and untreated groups of mice was measured by ultrasound over a 5-week period. Results: Using a mouse model, the effectiveness of a nanovaccine was determined. The nanoparticle conjugated with the NKT cell agonist induced robust IFN-γ and IL-4 response in wild-type mice while no response was elicited in NKT cell- or DC-deficient mice probed with the same nanovaccine. In a different mouse model group, treatment of tumor-bearing MUC-1 animals with the nanovaccine resulted in markedly diminished tumor growth compared to the untreated group. Conclusion: The results indicate that the nanoparticle delivery vehicle can induce a robust immune response in mice. Beyond this vehicular capability, the SPIO nanoparticles can be used as contrast agents for magnetic resonance imaging. As a result, this multimodal and multivalent nanovaccine, achieved through nanotechnology, has the potential to provide microanatomical and functional imaging feedback of the DC-targeted anti-cancer immunotherapy, thus leading to longitudinal treatment and monitoring.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1964. doi:1538-7445.AM2012-1964
Abstract 1965: Evaluating the use of Fe3O4@TiO2 nanoparticles and nanoconjugates with a HPV 18 E2 peptide as a potential therapy for HPV containing cancer cells
Authors: Doty Caroline B. , Yuan Ye , Wu Aiguo , Paunesku Tatjana , Woloschak Gayle E.
Published: August 2012

Over half a million women world wide are affected by cervical cancer each year. HPV, human papillomavirus, is currently seen as the causative agent of this form of cancer. There are multiple mechanisms by which HPV can cause cervical cancer, the primary mechanisms being the integration of HPV viral DNA into human DNA and the production of the viral oncoproteins E6 and E7. The mechanism of action of these oncoproteins lies in the deregulation of tumor suppressor proteins p53 and Rb. Current cervical cancer therapies, such as radiation, surgical removal, and chemotherapy target the cancerous cells but not the causative agent, HPV. The purpose of this investigation is to find the optimal formulation for, and evaluate the ability of, titanium dioxide (TiO2) shell - iron oxide (Fe3O4) core nanoconjugates (Fe3O4@TiO2) to target HPV genome as a method of therapy. Fe3O4@TiO2, which act the same as pure TiO2 nanoparticles, produce reactive oxygen species (ROS) in solution and have the ability to cleave DNA upon the induction of photon energies above 3.2 eV (e.g. white light), as was shown as a part of these studies. In this study, 6nm Fe3O4@TiO2 nanoconjugates were covalently linked, via a dopamine linker, to a truncated HPV 18 E2 peptide. The peptide linked to the nanoparticle is a 22 amino acid sequence that contains a nuclear localization sequence as well as a DNA binding motif. We hypothesized that (1) the Fe3O4@TiO2-PNA nanoconjugates would localize to the nucleus of cells; (2) presence of nanoconjugates in cells would lead to the production of reactive oxygen species (ROS) upon induction with white light; (3) presence of light activated nanoconjugates in cells would lead to double strand breaks in DNA. The nanoconjugate was tested in HeLa cells which contain multiple copies of HPV genome. To evaluate the effectiveness of this nanoconjugate therapy, we have used DCFDA staining to determine levels of ROS in cells upon the induction of light. As a method to determine double strand DNA damage, we have used immunofluorescence techniques to reveal changes in 53BP1 foci. Upon the introduction and induction of Fe3O4@TiO2-HPV 18 E2 peptide nanoconjugates in HeLa cells we have found increases in ROS levels and increases 53BP1 foci suggesting the presence of double strand DNA damage.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1965. doi:1538-7445.AM2012-1965
Abstract 1966: Plasmonic gold nanostars: A potential agent for molecular imaging and cancer therapy
Authors: Yuan Hsiangkuo , Khoury Christopher , Wilson Christy , Grant Gerald , Vo-Dinh Tuan
Published: August 2012

Gold nanoparticles offer great potential for bioapplication due to their biocompatibility, chemical stability, and plasmon tunability. Due to the increased demand in custom-designed bioapplication, tailoring nanoparticle's plasmon for a specific application remains an active area of research. Plasmonic gold nanostars, with their sharp tips and small cores, yield unique optical properties in the near infrared region favorable for biological applications. We present a high-yield biocompatible synthesis of gold nanostars, whose geometry is adjustable such that the plasmon band can be tuned into the near-infrared “tissue diagnostic window”. Nanostars offer several interesting plasmon properties including intense surface-enhanced Raman scattering (SERS) for ultrasensitive detection, strong two-photon photoluminescence (TPL) for real-time particle tracking, and efficient photothermal transduction for hyperthermic therapy. Here, we demonstrate nanostars tracking and photothermal ablation both in vitro and in vivo. Using SKBR3 breast cancer cells incubated with bare nanostars, photothermal ablation was observed within 5 minutes of irradiation (980 nm CW laser, 15 W/cm2). On a mouse preinfused systemically with PEGylated nanostars for 2 days, extravasation of nanostars was observed and localized photothermal ablation was demonstrated on a dorsal window chamber within 10 minutes of irradiation (785 nm CW laser, 1.1 W/cm2). These preliminary results have illustrated the theranostic potential of gold nanostars for the use in molecular imaging and cancer therapy.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1966. doi:1538-7445.AM2012-1966
Abstract 197: Epigenetic regulation of miRNA expression in osteosarcoma
Authors: Skarn Magne , Namlos Heidi M. , Ahmed Deeqa , Lind Guro E. , Meza-Zepeda Leonardo A. , Myklebost Ola
Published: August 2012

Epigenetic and genetic alterations of microRNAs (miRNAs) are frequently seen in cancer, and are responsible for the deregulation of differentiation and proliferation programs. The levels of transcription of miRNAs have been directly linked to epigenetic silencing, i.e. hypermethylation of CpG islands in tumors. Osteosarcoma is the most common primary malignant bone tumor and shows complex genomic aberrations. Using Illumina's Infinium technology we have profiled global promoter methylation of the EuroBoNeT osteosarcoma cell line panel (eurobonet.eu), in addition to a small panel of normal samples (osteoblast primary cultures and normal bone). A list of miRNAs that could be associated to a promoter CpG island was generated by identifying miRNAs that are encoded within transcripts of protein-coding host genes, or within 10 kb from a CpG island. Using an integrative approach, we have analyzed miRNA expression patterns together with DNA methylation data. Interestingly, hypermethylation of the upstream promoter seems to strongly suppress miRNA expression, and a high inverse correlation was observed between the degree of DNA methylation and expression of 17 miRNAs. The identified miRNAs were associated with hypermethylation in a high proportion of the osteosarcoma cell lines and hypomethylation in normal samples, suggesting that their transcription is regulated by promoter methylation, and that their silencing may play a role in osteosarcoma biology. To study this further, a subset of the cell lines was treated with a DNA demethylation agent. The relative expression levels of 8 miRNAs were found to increase upon treatment, as determined by quantitative RT-PCR. Thus, the transcription of these miRNAs seems to be regulated by epigenetic mechanisms. The methylation status of CpG islands associated with the most interesting miRNAs was then analyzed in more detail using methylation-specific PCR and direct bisulphite sequencing. We are currently expanding these investigations to a large tumor set where we will use quantitative methylation-specific PCR as a tool to determine the methylation status. Based on our findings, methylation of CpG islands seems to play a crucial role in controlling miRNA expression in osteosarcomas. This reveals new possibilities for activation of tumor-suppressing miRNAs by epigenetic treatment of osteosarcomas.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 197. doi:1538-7445.AM2012-197
Abstract 198: Identification of differentially expressed microRNAs and other non-coding RNAs in ependymomas
Authors: Costa Fabricio F. , Bischof Jared M. , Vanin Elio F. , Lulla Rishi R. , Sredni Simone T. , Rajaram Veena , Wang Min , Renaud Gabriel , Passetti Fabio , Tomita Tadanori , Goldman Stewart , Bonaldo Maria F. , Soares Marcelo B.
Published: August 2012

Ependymomas are tumors that present great challenges in treatment despite the advances in neurosurgical techniques and adjuvant therapy. In order to identify possible molecular markers that could improve clinical management and better treatment, we have profiled ependymomas for the expression of microRNAs (miRNAs) and other non-coding RNAs (ncRNAs). miRNAs are ncRNAs that can block mRNA translation and affect mRNA stability. Several lines of evidence have recently shown that up or down-regulation of miRNAs correlate with many human cancers indicating that they can function as classical tumor suppressors and/or oncogenes. In this study, we have evaluated with the use of TaqMan Low Density Arrays (TLDAs) and RNA-Seq the expression profiles of non-coding RNAs in ependymoma samples and normal brain tissue. We analyzed the miRNA expression profile of 34 ependymoma samples using paraffin tissue compared to 6 normal brain control samples enriched for ependymal cells. miRNA expression profiles were correlated with clinico-pathological parameters, morphological features and the location of the tumor in the brain. We have been able to classify the tumors based on the miRNA expression profile and to identify miRNAs that are differentilly expressed in ependymomas when compared to normal samples. For example, miR-135a, miR-594 and miR-34a were identified as over-expressed and miR-485-5p and miR-383 as down-regulated (p<0.01; FDR<0.05). We have also identified and are currently confirming some of the targets for these miRNAs. Finally, we have utilized high-throughput Whole Transcriptome (WT) analyses with the SOLiD system to identify other differentially expressed miRNAs and long ncRNAs in ependymomas. The transcriptome of 3 ependymomas and 2 controls were sequenced, thus generating approximately 5 Gb of data. In conclusion, using different strategies, we have been able to identify ncRNAs that are differentially expressed in ependymomas compared to normal ependymal tissue, some of which are of clinical importance. Financial Support: Children's Memorial Research Center, The Falk Brain Tumor Foundation and The Maeve McNicholas Memorial Foundation.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 198. doi:1538-7445.AM2012-198
Abstract 1989: The effect of resveratrol combined with DFMO or DenSpm on MCF-7 breast cancer cells and MCF-10a non-cancerous cells
Authors: Benassi Isabella , Smith Riley M. , White KateLyn , Dennis Shanna , Nelson Niki , Feirer Russ
Published: August 2012

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. Resveratrol has been shown to induce apoptosis and reduce both cell viability and mitotic index in many cancer cell lines, including MCF-7. The current work extends these studies to determine its effects on glucose utilization and enzymes involved in polyamine metabolism. Glucose uptake was found to be reduced in MCF-7 cells treated with resveratrol. Work in other labs has shown resveratrol to sensitize cancer cells to other chemotherapeutic compounds. In the present study, the effects of combinations of resveratrol with compounds that affect polyamine metabolism, DFMO (difluoromethylornithine) and DenSpm (N1, N11-diethylnorspermine), were tested. Both DFMO and DenSpm were found to reduce cell proliferation and mitotic index in MCF-7 cell lines and more importantly, a synergistic effect was observed when these compounds were used in combination with resveratrol. In this investigation resveratrol was also found to induce apoptosis and reduce cell viability, mitotic index, and glucose uptake in non-cancerous, transformed mammary epithelial cells (MCF-10a). Similar findings have been reported with other non-cancerous cells including intestinal smooth muscle cells (Garcia et al., 2011). The combination of resveratrol and DFMO also reduced glucose uptake, proliferation, and mitotic index in this non-cancerous cell line (MCF-10a). These compounds were found to affect the expression of ODC (ornithine decarboxylase) and SSAT (spermidine/spermine acetyl transferase), enzymes involved in polyamine metabolism, and other proteins involved in cell cycle regulation.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1989. doi:1538-7445.AM2012-1989
Abstract 1993: Fishing for artemisinin-interacting proteins from human nasopharyngeal cancer cells
Authors: Eichhorn Tolga , Schloissnig Siegfried , Lehmann Wolf-Dieter , Mertens Rolf , Krauth-Siegel Luise , Efferth Thomas
Published: August 2012

Determining cellular target molecules of drugs by chemical proteomic techniques is complex and tedious. Most approaches rely on activity-based probe profiling and compound-centric chemical proteomics. The antimalarial artemisinin also exerts profound anti-cancer activity, but the mechanisms of action are incompletely understood. In the present study, we have identified artemisinin-interacting target proteins from human nasopharyngeal carcinoma cell line CNE1. Thereby, our approach overcomes usual problems in traditional fishing procedures, because the drug was attached to a polystyrene surface without further chemical modification. Using mass spectrometry we have identified 20 proteins which effect cell cycle arrest, apoptosis, inhibition of angiogenesis, disruption of cell migration, and modulation of nuclear receptor responsiveness. One protein out of the twenty was further investigated in vitro for direct ligand binding. Furthermore, a blind-docking based approach confirmed experimentally identified proteins and suggested further interacting proteins. Theoretically predicted interaction partners may serve as a starting point to complete the whole set of proteins binding artemisinin. In our investigations, we have comprised artemisinins role in cancer treatment in a greater shape through a systematic biological strategy and thus, are able to show novel insights into its mode of action.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1993. doi:1538-7445.AM2012-1993
Abstract 1995: Huachansu inhibits proliferation of non-hodgkin lymphoma cells by induction of apoptosis
Authors: Efuet Ekem T. , Cohen Lorenzo , Yang Peiying
Published: August 2012

Huachansu, a hot water extract of venom or the skin glands of Bufo gargarizans or B. melanostictus, has been used in the treatment of various cancers in Asia and in China. Despite extensive use in the treatment of various solid tumors such as pancreatic, hepatocellular, non-small-cell lung carcinomas, its effect on the growth of malignancies of hematopoietic and non-hematopoietic origin, particularly lymphomas, is limited. Here we investigated the anti-proliferative effect and molecular mechanisms of Huachansu in non-Hodgkin lymphoma Raji, Ramos, BJAB and Namalwa cells. These cells were treated with Huachansu (0 to 50 αl/ml) for 72 hrs and cell proliferation was assessed by WST-1 assay. The molecular mechanism associated with Huachansu's anti-proliferative effect was examined by western blotting, cell cycle and apoptosis as determined by PI and Annexin V staining. Huachansu inhibited proliferation of all four lymphoma cell lines tested with IC50 ranging from 6.7 αl/ml to 17.1 αl/ml. At a low concentration of 25 αl/ml, Huachansu triggered a sub G1 arrest in both Raji and Ramos cells, indicative of cell death while also causing a marked increase of early to late apoptotic cell death in both cell lines. Intriguingly, the expression of MCL-1 proteins was markedly reduced by Huachansu at 12.5 αl/ml in Raji cells, while completely blocked at 25 αl/ml in Ramos cells. At 50 αl/ml, Huachansu decreased total Akt more robustly in Ramos compared to Rajis cells, with no significant reduction in the levels of survivin. Huachansu (25 αl/ml) inhibited the expression of pRB proteins in Raji cells and substantially increased the levels of caspase-3 in Ramos (12.5 αl/ml) in a concentration dependent manner, indicative of apoptosis. Given that bufalin is one of the major bioactive components of Huachansu, we tested its effect on the proliferation of Ramos cells. Bufalin (125 ng/ml) indeed suppressed the proliferation of Ramos cells. The effect of both Huachansu and bufalin on transcriptome of Ramos cells is currently being investigated and will be reported. Collectively, our data suggest that Huachansu is effective in inducing cell death and apoptosis, in part, by upregulatiing caspase-3 activity and inhibiting the phosphorylation of RB protein in lymphomas. Considering that the concentration of Huachansu needed to inhibit cell proliferation by 50% was similar to the dose of Huachansu routinely used in the clinics in China, our preliminary data suggests that Huachansu has a great potential to be developed as an anticancer agent for non-Hodgkin lymphoma and warrant further investigation. This study is supported in part by Gabrielle's Angel Foundation.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1995. doi:1538-7445.AM2012-1995
Abstract 2007: Differential roles of BCL-XL and BCL-2 in protecting mitochondria against oxidative stress in CML cells
Authors: Zhang Hui , Lu Weiqin , Liu Terrence , Chen Gang , Chen Zhao , Trachootham Dunyaporn , Arlinghaus Ralph B. , Huang Peng
Published: August 2012

Previous studies have identified that BCR-ABL elevates cellular reactive oxygen species (ROS) through mitochondria and NAD(P)H oxidase (NOX). However, it is still unknown how BCR-ABL over-expressed cells can maintain such altered redox status, while escaping from the persistent oxidative stress-induced cell damage or apoptosis. Therefore elucidation of the mechanisms by which CML cells cope with oxidative stress will provide important insights into the molecular events leading to leukemia development and drug resistance. The major goals of this study are to investigate the role of BCR-ABL-regulated downstream cell survival factors in providing an adaptive mechanism which allows CML cells to survive in the presence of cellular oxidative stress, and to evaluate the potential therapeutic implications. Several experimental models were used to test the cellular redox status and relative sensitivity of oxidative stress-induced cell death in our study, including BCR-ABL inducible cell lines, BCR-ABL stably transformed cell lines and BCR-ABL-expressing CML blast crisis cells with different BCL-XL/BCL-2 patterns. Additionally, we established an artificial CML cell model with heterogenic BCL-XL/BCL-2 expression to assess the correlation between cell survival factor genetic background and cell sensitivity to Imatinib and oxidative stress. In this study, BCL-XL has been identified as the major survival factors responsive to BCR-ABL-promoted cellular oxidative stress and plays a dominant role in regulating the threshold of oxidative stress-induced apoptosis. The cell survival factors BCL-XL and BCL-2 differentially protect mitochondrial integrity under oxidative stress. BCL-XL is an essential survival factor in maintaining viability of the cells with the excessive ROS while BCL-2 seems to play a relatively minor role. In addition, combination of redox-modulating reagent α-phenethyl isothiocyanate (PEITC) with BCL-XL/BCL2 inhibitor ABT737 or suppression of BCL-XL expression by BCR-ABL inhibitor Gleevec dramatically sensitizes CML cell to ROS stress-induced apoptosis. These data together suggest that elevation of BCL-XL is important for the development of CML, and that redox-directed therapy may merit further clinical investigations in CML treatment.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2007. doi:1538-7445.AM2012-2007