bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract B234: LY2835219, a potent oral inhibitor of the cyclin-dependent kinases 4 and 6 (CDK4/6) that crosses the blood-brain barrier and demonstrates in vivo activity against intracranial human brain tumor xenografts.
Authors: Sanchez-Martinez Concepcion , Gelbert Lawrence M. , Shannon Harlan , De Dios Alfonso , Staton Brian A. , Ajamie Rose T. , Sawada Geri , Wishart Graham N. , Raub Thomas J.
Published: June 2012

Effective treatments for primary brain tumors and brain metastases represent a major unmet medical need. The blood-brain barrier (BBB) arises from both a structural barrier and drug efflux transporters that prevent most anti-cancer drugs from efficiently reaching brain tumors or metastases. The CDK4/6 pathway (CDK4/6-cyclin D1-Rb-CDKN2) plays a key role in regulating cellular proliferation. The importance of this pathway is highlighted by its inactivation in a majority of human tumors including glioblastoma multiforme. We have identified and characterized a potent and selective dual cdk4/6 inhibitor, LY2835219. Preclinical characterization was performed with the monomesylate salt (LY2835219-MsOH), which inhibits these kinases with IC50 values of 2 and 10 nM for CDK4 and CDK6, respectively. LY2835219-MsOH is a potent inhibitor of Rb phosphorylation in vitro and in vivo that induces G1 specific arrest and inhibition of tumor growth. To determine the potential of LY2835219-MsOH for the treatment of brain tumors and metastases, we assessed the ability of LY2835219-MsOH to cross the BBB and its interaction with the P-gp and BCRP efflux pumps that are expressed at the BBB. Using MDCK cells over-expressing either human ABCB1 (P-gp) or mouse abcg2 (Bcrp), LY2835219-MsOH and a second CDK4/6 inhibitor (PD0332991) are substrates for these two pumps, but each cross the murine BBB in vivo to a different degree. Unlike PD0332991, LY2835219-MsOH saturates BBB efflux with an unbound plasma IC50 of ∼95 nM (1.8 uM total plasma). The percent of dose in brain for LY2835219-MsOH is 0.5–3.9% and is comparable to that for temozolomide (1.9% plasma). In both a subcutaneous and intracranial human glioblastoma model (U87MG), LY2835219-MsOH suppressed tumor growth in a dose-dependent manner both as a single agent, and in combination with temozolomide. In summary, LY2835219-MsOH is a potent and selective oral CDK4/6 inhibitor that crosses the BBB and inhibits the growth of intracranial tumors alone or in combination with other agents.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr B234.
Abstract B36: Exploring potential clinical application of cetuximab in NSCLC: Efficacy study in a large panel patient derived xenograft (PDX) model.
Authors: Yang Mengmeng , Chen Dawei , Yang Jie , Deng Jiangyun , Song Xiaoming , Cai Jie , Chen Taiping , Chen Yiyou , Li Henry
Published: June 2012

NSCLC is a common cancer with one of the highest mortality numbers and few effective treatment options, except those with EGFR and ALK activating mutations. Cetuximab has been approved for CRC and H&N, but not yet for NSCLC. In this study, we set out to explore potential clinical utilities by testing cetuximab in a large cohort of patient derived xenograft (PDX) models (over established 60 models).

Among the 12 NSCLC models tested so far, 5 out of 12 were found to be sensitive (42%), with all of which have wild-type KRAS and EGFR except for 1 model that carries an EGFR exon-20 a short in-frame insertion. These data suggest that cetuximab could potentially benefit a subgroup of patients, although it remains to be seen whether cetuximab can offer additional benefit besides standard chemotherapy regimens through combinational therapies. Among the 7 resistant models, two of them have L858R mutation in EGFR, a known driver mutation for non-smoking Asian female patients who are sensitive to gefitinib treatment. This data suggests that although both cetuximab and gefitinib can block EGFR signaling, the mechanism of action may also play an important role in tumor response to drugs. Analysis of genomic analysis did not reveal obvious relationship between cetuximab sensitivity and EGFR expression level, nor EGFR copy number. This could be attributed the relative small cohort size so far.

Although the current study suggests that EGFR L858R mutation might be negatively correlated with response to cetuximab, additional studies with more PDX models are needed to further substantiate this observation, and for uncovering other biomarkers which could potentially predict patient populations who can benefit from cetuximab treatment.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr B36.
Abstract B37: F14512, a polyamine-vectorized anticancer drug, triggers senescence cell death mechanism.
Authors: Brel Viviane , Annereau J-Philippe , Gomes Bruno , Vandenberghe Isabelle , Andre Karine , Marionneau Marie-Laure , Lacastaigneratte Laurence , Stennevin Aline , Rouquet Jerome , Latil Alain , Kruczynski Anna , Bailly Christian , Guilbaud Nicolas
Published: June 2012

Drugs specifically vectorized to cancer cells may offer a reinforced activity, resulting in an improved therapeutic index. In this context, F14512 exploits the Polyamines Transport System (PTS) to accumulate into cells and exhibits an enhanced anti-proliferative activity on a large panel of tumor cell lines as compared to etoposide. At the molecular level, the spermine tail of F14512 contributes to enhance the water solubility of the drug, and reinforces the activity of the drug toward its primary molecular target, topoisomerase II. This observation has encouraged the set up of a phase 1 clinical study with F14512 in patients with relapsed or refractory acute myeloid leukemia (AML).

In order to determine how these molecular properties translate at the cellular level, we have compared the kinetic of cell cycle modulation associated with the inhibition of cell proliferation. F14512 proved to be >30-fold more cytotoxic than etoposide against A549 non-small cell lung cancer cells and triggers less but unrecoverable DNA damages and does not lead to a marked accumulation in the S-phase of the cell cycle, unlike etoposide. Interestingly, A549 cells treated with F14512 were less prone to undergo apoptosis (neither caspases-dependent, nor caspases-independent pathways) or autophagy but preferentially entered into senescence. Drug-induced senescence was characterized qualitatively and quantitatively by an increased -galactosidase activity, both by cytochemical staining and by flow cytometry. A morphological analysis by electron microscopy revealed the presence of numerous multi-lamellar and vesicular bodies and large electron-lucent vacuoles in F14512-treated cell samples. The mechanism of drug-induced cell death is thus distinct for F14512 as compared to etoposide, and this difference may account for their distinct pharmacological profiles and the superior activity of F14512 in vivo. The identification of such response markers for senescence are currently pursued on in vivo MX-1 models by following a transcriptomic analysis focused on cell death cascades including apoptosis and senescence. This study suggests that senescence markers should be considered as potential pharmacodynamic biomarkers of F14512 antitumor response, applicable in clinical trial.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr B37.
Abstract B6: Aminopeptidase N-activated prodrug melphalan-flufenamide (J1) inhibits angiogenesis in vitro and in vivo.
Authors: Laitinen Sara , Wickstrom Malin , Fuchs Peder Fredlund , Gerwins Par , Larsson Rolf , Gullbo Joachim
Published: June 2012

Introduction: The membrane-bound metalloproteinase aminopeptidase N (APN) is involved in several different cellular processes associated with the malignant phenotype. Furthermore APN has also been reported to have a functional role in tumor angiogenesis and there appear to be a strong correlation between the expression of APN and the invasive capacity of a numerous tumor cell types. The melphalan-derived prodrug melphalan-flufenamide (previously designated J1) can be activated by APN suggesting possible anti-angiogenic properties.

Experimental: A series of experiments were performed to evaluate the effects of melphalan-flufenamide on angiogenesis; cytotoxicity on bovine endothelial cells, the TCS Cellworks AngioKit model with human endothelial cells co-cultured with fibroblasts, the chicken embryo chorioallantoic membrane assay, and finally in vivo in mice using the Cultrex DIVAA angio-reactor assay.

Results: Melphalan-flufenamide displayed high cytotoxic activity against endothelial cells, about hundred times more potent than the parental substance melphalan. This difference was also demonstrated in the more complex assays. Melphalan-flufenamide-treated AngioKit co-cultures showed significant superiority compared to melphalan regarding total tubule number, total tubule length, mean tubule length, and number of junctions. Finally mice were implanted subcutaneously with DIVAA angio-reactors, i.e. sterile tubes with a VEGF gel matrix, and treated with drugs. Melphalan-flufenamide was the most effective compound inhibiting in-growth of host micro-vessels in the tube, significantly better than melphalan and slightly better than the positive control bevacizumab.

Conclusion: APN is associated with several characteristics of the malignant phenotype, including angiogenesis. Melphalan-flufenamide is an APN-activated prodrug of melphalan, currently being evaluated in clinical trials. This study suggests that melphalan-flufenamide besides being an alkylating agent also demonstrates anti-angiogenic effects in different preclinical models in vitro and in vivo.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr B6.
Abstract C122: Phase 1b relative bioavailability (BA) study of enteric coated tablet (ECT) in reference to powder in capsule (PIC) formulation of the investigational drug alisertib (MLN8237), an Aurora A Kinase (AAK) inhibitor, in patients with advanced nonhematologic malignancies.
Authors: Venkatakrishnan Karthik , Infante Jeffrey R. , Cohen Roger B. , Burris Howard A. , Zhou Xiaofei , Liu Hua , Fingert Howard , Dees E. Claire
Published: June 2012

Background: The investigational drug alisertib (MLN8237) is an orally available, selective AAK inhibitor. Early clinical studies used a PIC formulation; an ECT formulation was recently developed. Here we present relative BA results of ECT referenced to PIC designed to bridge transition to ECT in MLN8237 clinical development.

Methods: Eligible patients were age ≥18 years with advanced solid tumors and ECOG PS 0–1. Dose-escalation cohorts received alisertib 10 mg BID (N=1), and 20 mg BID (N=1), before formal relative BA evaluation at 40 mg BID, in a 7-day schedule followed by 14 days' rest (21-day cycles). Patients received MLN8237 40 mg BID as either ECT or PIC in a 2-cycle, 2-way cross-over design. Pharmacokinetic (PK) sampling was performed on Day 7 of cycles 1 and 2 to characterize steady-state PK of alisertib formulated as ECT or PIC for relative BA analysis. PK was also evaluated on Day 1 of ECT dosing.

Results: 22 patients were included (N=1 each at 10 and 20 mg BID; N=20 at 40 mg BID); 55% were male, 90% were white, and median age was 56 years. 14 patients were evaluable for relative BA analysis. Following BID oral dosing, absorption was fast (median Tmax ∼2.5 hours for ECT; ∼2 hours for PIC). Relative BA of ECT referenced to PIC was 90% (90% CI: 74.4, 108.8). Steady-state Cmax following ECT was 82% of that from PIC (90% CI: 69.9, 95.5). Mean accumulation ratio of ECT BID was ∼2.8-fold; mean peak-to-trough ratio was ∼2.5. The range of dose-normalized exposures following ECT was within the corresponding range observed with PIC, which has previously been associated with favorable pharmacodynamic effects (Dees et al. Abstract 3010; Cervantes et al. Abstract 3031, J Clin Oncol 2010;28:15s).

Conclusions: Systemic exposures following administration of ECT and PIC formulations of alisertib are generally similar, supporting transition from PIC to ECT in clinical development. Taken together with PK, pharmacodynamics, and antitumor activity from other trials, these data indicate that the ECT formulation of alisertib can provide exposures needed for clinically relevant bioactivity.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr C122.
Abstract C184: A small molecule FAK inhibitor increases the cytotoxicity of 5-fluorouracil.
Authors: Melissa Heffler , Golubovskaya Vita M. , Cance William G. , Dunn Kelli M. Bullard
Published: June 2012

Introduction: Focal adhesion kinase (FAK) is a nonreceptor tyrosine kinase that has been implicated in colon cancer progression. We have shown that SW620 colon cancer cells express both FAK and activated (phosphorylated) Y397 FAK. 1,2,4,5-Benzenetetraamine tetrahydrochloride (Y15) is a small molecule FAK inhibitor that decreases cell viability and tumor growth in vivo. Because chemotherapy for colon cancer is based upon regimens containing 5-fluorouracil (5-FU), we hypothesized that combining Y15 with 5-FU would synergistically inhibit colon cancer cell viability and growth in vitro and in vivo.

Methods: SW620, SW480 and HCT116 colon cancer cells grown in culture were treated with Y15 and 5-FU alone and in combination. In vitro viability was assessed with an MTT assay. To test the in vivo affects of these agents, SW620 cells were injected into the flank of female nude mice. The mice were then treated with either Y15 (100mg/kg oral gavage), 5-FU (30mg/kg intraperitoneal injection), combination Y15+5-FU, or PBS control (30mg/kg intraperitoneal injection). Tumors were measured with calipers every 3 days and tumor volumes calculated.

Results: MTT assays demonstrated synergistic inhibition of cell viability with combination Y15+5-FU treatment. The viability of SW620 cells treated with 2microM of Y15 and 50microM of 5-FU was significantly less than that of cells treated with either agent alone (p< 0.05). This trend persisted with dual treatment consisting of 2microM of Y15 and increasing doses of 5-FU (100microM, 200microM, 300microM, p< 0.05). SW480 cells showed similar synergism, with the viability of cells treated with 4microM of Y15 and 50microM of 5-FU significantly less than that of cells treated with either agent alone (p<0.05). Similarly, the viability of HCT116 cells treated with a combination of 500nM of Y15 and 200microM of 5-FU was significantly less than that of cells treated with either agent alone (p<0.05). In vivo, oral gavage Y15 (100mg/kg) and 5-FU (30mg/kg) as single therapies did not inhibit tumor growth. However, mice treated with Y15+5-FU developed tumors that were significantly smaller than single treatment or control groups after 27 days of treatment (p< 0.05).

Conclusions: The small molecule FAK inhibitor, Y15, increases the cytotoxic activity of 5-FU against colon cancer cells in vitro. In vivo, at a dose where neither agent decreases tumor growth, the combination of Y15 and 5-FU significantly inhibits tumor growth. These data suggest that Y15 augments the effect of 5-FU and suggests that the addition of this small molecule FAK inhibitor may be a good therapeutic adjunct for treating colon cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr C184.
Abstract C81: Therapeutic potential of SHIP1 and SHIP2 inhibitors in cancer.
Authors: Kerr William G. , Brooks Robert , Park Mi-Young , Gumbleton Matthew , Iyer Sonia , Viernes Dennis , Chisholm John , Fuhler Gwenny Manel
Published: June 2012

Many tumors present with increased activation of the phosphatidylinositol 3-kinase (PI3K)-PtdIns (3,4,5) P3- protein kinase B (PKB/AKT) signaling pathway. The lipid phosphatases SHIP1 and SHIP2 have long been thought to act as tumor-suppressors by counteracting the survival signal induced by this pathway through hydrolysis or PtdIns (3,4,5) P3 to PtdIns (3,4) P2. However, a growing body of evidence suggests that PtdInd (3,4) P2 is capable of, and essential for, AKT activation, thus opening up a potential role for SHIP1/2 enzymes as proto-oncogenes. We have recently described a novel SHIP1 selective chemical inhibitor (3AC), which was capable of killing malignant hematological cells. In this study, we further investigate the biochemical consequences of 3AC treatment in multiple myeloma (MM) cells, and demonstrate that SHIP1 inhibition arrests MM cell lines in either G0/G1 or G2/M stages of the cell cycle, leading to caspase activation and apoptosis. In addition, we show that in vivo growth of MM cells is blocked by treatment of mice with the SHIP1 inhibitor 3AC. Furthermore, we identify three novel pan-SHIP1/2 inhibitors (1PIE, 2PIQ, 6PTQ), which efficiently kill MM cells through G2/M arrest, caspase activation and apoptosis induction. Interestingly, in SHIP2-expressing breast cancer cells, pan-SHIP1/2 inhibition also reduces viable cell numbers, which can be rescued by addition of exogenous PtdIns (3,4) P2. In conclusion, this study shows that inhibition of SHIP1 and SHIP2 may have broad clinical application in the treatment of multiple tumors.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr C81.
Abstract C87: Combination of chemotherapy and Akt inhibitor is synergistic in gastric cancer cell lines.
Authors: Almhanna Khaldoun , Cubitt Christopher , Zhang Shumin , Malafa Mokenge
Published: June 2012

Background: Molecularly-targeted agents failed to improve outcome in gastric cancer. MK-2206 (Merck & Co., Inc.) is an oral potent allosteric Akt inhibitor. In this study we evaluated the synergistic potential of MK-2206 in combination with selected chemotherapeutic agents (Carboplatinum, Paclitaxel) in human gastric cancer cell lines.

Materials and Methods: We evaluated effects of MK-2206 on cell growth and cell signaling using a panel of gastric cancer cell lines AGS, SNU-1 and SNY 16. The analysis of drug combinations was conducted by using CellTiter-Blue™ Cell Viability Assay which yielded the combination index (CI). MK-2206 and representative chemotherapy agent were further evaluated regarding their effects on Akt inhibition and downstream targets using western blots propped with the appropriate antibodies. We assessed the combination of MK-2206 and chemotherapy in three different treatment sequences.

Results: We demonstrated in vitro synergistic efficacy of MK-2206 when combined with carboplatinum and paclitaxel in the three cell lines examined. Efficacy was dose dependent. We assessed the combination of MK-2206 and carboplatin/paclitaxel in three different treatment sequences; Twenty-four hours of exposure to combination chemotherapy followed by a 48-hour exposure to MK-2206 resulted in the highest synergistic antiproliferative effect in all cell lines. On the other hand, the reverse sequence (MK-2206 followed by chemotherapy) and the concurrent treatment schedule were slightly synergistic or additive as well. The effects of MK-2206 on p-Akt and other downstream targets will be available at the meeting.

Conclusions: Our findings suggest that Akt inhibition augments the efficacy of existing gastric cancer therapeutics (carboplatinum and paclitaxel); thus, MK-2206 is a promising agent to treat gastric cancer patients who receive these cytotoxic agents. The altitude of synergy depended on the treatment sequence; a schedule of MK-2206 dosed before or concurrently with chemotherapy was not as effective as being dosed after chemotherapy. Further experiments addressing MK-2206's mechanism of action in combination with chemotherapy are ongoing.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr C87.
Abstract C98: Evaluation of the PAXgene tissue system: Preservation of morphology and gene expression in human melanoma.
Authors: Hesse Peter , Wyrich Ralf , Voss Thorsten , Rainen Lynne , Groelz Daniel
Published: June 2012

Introduction: PreAnalytiX has recently developed the PAXgene® Tissue System, a formalin-free tissue fixation method for simultaneous preservation of tissue morphology and biomolecules. In this study, PAXgene Tissue was used to stabilize human melanoma specimens. Mirrored samples of melanoma were fixed with either neutral buffered formalin or PAXgene Tissue, or snap frozen in liquid nitrogen (LN2) and were compared for preservation of morphology, antigenicity, RNA and noncoding small RNAs.

Materials and Methods: Three cases of melanoma were equally divided into two parts: one part was fixed with PAXgene Tissue reagents, the second part of cases 1 and 2 were fixed with formalin and the second part of case 3 was snap-frozen in LN2. Formalin and PAXgene Tissue fixed samples were processed and embedded in paraffin (resulting in FFPE and PFPE tissue respectively). Tissue sections were stained with H&E or immunohistochemically for Ki-67 and S100. RNA or total RNA including miRNA was purified from all samples and analyzed for purity, integrity and performance in RT-qPCR assays on a TaqMan® PCR Array for expression analysis of 32 different human endogenous control genes and in 26 different single assays specific for non-coding, small RNAs.

Summary of results: H&E morphology was well preserved in sections of FFPE and PFPE. After optimization of the heat induced epitope retrieval step for PFPE samples, antigen localization, staining intensities, and number of stained cells were equivalent in FFPE and PFPE tissue for Ki67 and S100. RNA purity was generally high with A260/A280 values >1.9 for all samples. RNA integrity as measured on Agilent Bioanalyzer ranged from 7.7 to 9.5 for LN2 samples, between 3.7 to 6.7 for PFPE and 2.1 to 2.8 for FFPE samples. Correlation of gene expression results in qRT-PCR was high between RNA from PFPE and LN2 (R2 = 0.99). Correlation between mRNA from PFPE and FFPE tissue was much lower (R2 =0.86). In contrast, when all the results from 26 different single non-coding, small RNA specific qRT-PCR assays were compared, there was a high correlation between miRNAs from PFPE with LN2 (R2 = 0.99) as with PFPE and FFPE (R2 = 0.99).

Conclusion: The PAXgene Tissue System preserves morphology, antigenicity, RNA and miRNA profiles in human melanoma specimens enabling morphological and multimodal biomarker testing with one sample. Disclaimer: For research use only. Not for use in diagnostic procedures. No claim or representation is intended to provide information for the diagnosis, prevention, or treatment of disease.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr C98.
Abstract CN07-02: Target discovery with Oncomine: Discovering new targets and positioning old targets by integrative analysis of 10,000s of tumor genomes and transcriptomes.
Authors: Rhodes Daniel R. , Anstett Matthew A. , Williams Paul D. , Wyngaard Peter
Published: June 2012

The identification of oncogenic protein kinases in cancer has prompted the development of several novel targeted therapies. In many cases, such therapies have elicited dramatic clinical responses in patients harboring genetic activation of the target. To identify novel targets and additional opportunities to apply existing targeted therapies, we undertook a systematic analysis of somatic mutations and DNA copy number alterations across 10,000+ of cancer patients from The Cancer Genome Atlas (TCGA), COSMIC and Oncomine™ databases. We applied multiple analysis strategies to filter genetic alterations for those most likely to exert a ‘driver’ oncogenic effect. For somatic mutation data, we prioritized likely oncogenes as those with frequent hotspot mutations and infrequent nonsense mutations. For copy number data, we prioritized likely oncogenes as those undergoing frequent, high-level focal amplifications resulting in concomitant over-expression in amplified cases. To identify additional opportunities to apply existing targeted therapies, we characterized 22 specific kinases that are targeted by approved or investigational therapies. Among the 22 kinases, nearly all showed evidence for recurrent hotspot mutations or high-level focal amplifications in at least a small fraction of tumors. This objective analysis confirmed well known associations between genetic alterations and particular cancer types, but also identified several novel associations, usually in small sub-populations, suggesting additional indications for existing therapies. In addition to this focused analysis, we also conducted a genome-wide survey of all genes with evidence for oncogenic alterations and the cancer types with most frequent alterations. While most of the top hits correspond to well-known oncogenes, several novel candidate oncogenes were prioritized.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr CN07-02.
Abstract CN07-04: Patient-specific pathway analysis using PARADIGM identifies key activities in multiple cancers.
Authors: Stuart Joshua M.
Published: June 2012

While common pathways are believed to be shared within specific cancer types, the mechanisms of why particular patients respond differently to treatment is not fully understood. Current - omics studies such as The Cancer Genome Atlas (TCGA) give us powerful tools to search for pathways universal or specific to cancers. Our integrated approach makes use of multiple measurements including large-scale whole-genome mRNA expression, DNA copy number, and epigenetic features. Typical analysis of these measurements relies on integrating data from multiple samples to distinguish signal from noise. However, few analytical methods allow for sample-specific differences to identify features and pathways that are significant for prognosis and clinical treatment classifications.

Using our pathway analysis method PARADIGM (PAthway Recognition Algorithm using Data Integration on Genomic Models) (Bioinformatics (2010) vol. 26 (12) pp. i237) we computed pathway activities for the approximately 1685 available TCGA samples with both copy-number and gene expression data across 10 tissues to identify both common and differential pathway features When clustered together using hierarchical clustering methods, we see well-known associated cancers as clustering together such as Colon adenocarcinoma (COAD) with Rectum adenocarcinoma (READ) and Ovarian serous cystadenocarcinoma (OV) with invasive Breast carcinoma (BRCA). Interestingly Glioblastoma multiforme (GBM) and both types of Kidney (KIRC, KIRP) tend to cluster together, apparently driven by relatively low integrin signals and lower DNA damage response levels shared among the three tissues. Using this global cancer dataset we find striking similarities between subtypes of cancers from different tissues of origin. In particular, we find that a signature trained to recognize Lung adenocarcinoma (LUAD) versus Lung squamous cell carcinoma (LUSC) can be used to classify breast cancer subtypes Luminal A versus Basal with a surprising accuracy of 0.972. This analysis illustrates the molecular similarities between these cancers and warrants further characterization to assess the viability of bridging treatments between these and other cancers.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr CN07-04.
Abstract PL02-02: BRAF and RAS signaling in cancer: From biology to therapeutics.
Authors: Marais Richard
Published: June 2012

The RAS proteins are small G-protein that are activated downstream of cell surface receptors. The RAF proteins are protein kinases that are activated by RAS. RAF proteins then activate the MEK/ERK signalling pathway, which stimulates cell proliferation and drives tumorigenesis. There are three RAS proteins (HRAS, KRAS, NRAS) in humans and the NRAS isoform is mutated in about 25% of melanomas. There are also three RAF proteins in humans (ARAF, BRAF and CRAF) and BRAF is mutated in a further 50% of melanomas. Critically, drugs that target BRAF achieve impressive objective responses in patients with BRAF mutant melanoma, but are ineffective in patients whose melanomas express wild-type BRAF. These data validate mutant BRAF as a therapeutic target in melanoma.

An unexpected property of RAF inhibitors is that they drive paradoxical activation of the MEK/ERK pathway in cells that express oncogenic RAS. This is because when they bind to RAF in cells in the presence of oncogenic RAS, these inhibitors drive the formation of CRAF:BRAF heterodimers and CRAF:CRAF homodimers in which one partner is drug-bound and the other is drug-free. Critically, the drug-bound partner acts as a scaffold, or induces a conformation change that hyper-activates the drug-free partner and this partner then drives pathway signalling. Notably, a quarter to a third of patients on BRAF inhibitors develop cutaneous squamous cell carcinomas (cuSCC) and keratoacanthomas. We have used a two-stage skin carcinogenesis model in mice that is driven by oncogenic HRAS to show that while BRAF inhibitors accelerate the development of RAS-driven cuSCC in mice, they do not initiate the formation of these lesions. We found that about 60% of BRAF-inhibitor driven cuSCC in melanoma patients harbour mutations in RAS genes and furthermore show that in mice cuSCC development driven by BRAF inhibitors can be blocked by co-administration of a MEK inhibitor. Thus, we conclude that RAS inhibitors do not act as tumor promoters per se; rather they accelerate the inevitable in susceptible patients and we provide a rational approach to blocking this side effect in BRAF mutant melanoma patients.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr PL02-02.
Abstract 1006: TP53-induced glycolysis and apoptosis regulator (TIGAR) induces NADPH production and growth in nasopharyngeal carcinoma cells
Authors: Lam Emily KY , Lui Vivian WY , Wong Elaine YL , Lau Cecilia PY , Wong Cesar SC , Hui Edwin P , Chan Andrew SK , Tsao Sai Wah , Mills Gordon B , Chan Anthony TC
Published: June 2012

TIGAR (TP53-induced glycolysis and apoptosis regulator) is a novel dual regulator of glycolysis and apoptosis regulated by p53. TIGAR was first found to protect normal cells from oxidative stress by inducing cellular production of NADPH, a powerful reducing agent in the cell, via the pentose phosphate shunt.

Nasopharyngeal carcinoma (NPC) is a highly metastatic head and neck cancer prevalent in Southeast Asia. Our previous studies demonstrated that overexpression of TIGAR rescued NPC cells from growth inhibition induced by c-Met kinase inhibitors and an RNA anti-metabolite (ECyd), suggesting an anti-apoptotic function of TIGAR in NPC. Here, we demonstrated by Western blotting and immunohistochemistry that TIGAR was expressed in primary tumor biopsies of NPC. Moreover, NPC cell lines from various differentiation status also expressed TIGAR. Using an Epstein-Barr virus-associated NPC cell line, HONE-1-LMP1 cells, we showed that specific knockdown of TIGAR by siRNA inhibited cell proliferation (∼45%) at 48 hrs. Moreover, TIGAR overexpression markedly increased NPC cell proliferation (>300%), which was accompanied by significant induction of cellular NADPH production (>200%). This indicates that TIGAR-induced generation of NADPH, which is an important building block for major cellular metabolites for proliferation (including DNA, RNA and fatty acids, etc), may be involved in NPC carcinogenesis. Furthermore, TIGAR overexpression induced the expression of a pro-survival protein, Mcl-1 in NPC cells, which supports an anti-apoptotic function of TIGAR in NPC. Our results implicate that TIGAR may confer survival benefits to NPC cells via metabolic alteration.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1006. doi:10.1158/1538-7445.AM2011-1006
Abstract 1023: Social stress modulates beta-adrenergic and potassium channel-mediated signaling in lung adenocarcinoma
Authors: Plummer Howard , Al-Wadei Hussein A.N. , Unger Benjamin , Schuller Hildegard M.
Published: June 2012

Small airway epithelial cell-derived adenocarcinoma is the most common human lung cancer. Previous research from our laboratory has indicated the importance of stress neurotransmitters in cancer signaling in these cells in vitro. In the current study, we have assessed the potential modulation of cancer progression by social stress in xenograph models. The adenocarcinoma cell lines NCI-H322 (with activating point mutations in K-ras) and NCI-H441 (without ras mutations) were injected into nude mice 4 weeks after induction of social stress. The social stress continued for an additional 4 weeks when the tumors were removed. RNA was isolated, and PCR microarrays were used to identify genes that could be affected by stress. Using real-time PCR, we investigated some of these genes. We saw significant decreases in β1-adrenergic (0.49 fold), β2-adrenergic (0.55 fold) and calmodulin (0.16 fold) gene expression in the NCI-H322 xenographs. In the NCI-H441 xenographs, only calmodulin was changed (1.59 fold increase). The immortalized normal human small airway epithelial cell HPL1D was chosen for in-vitro studies. Treatment of HPL1D cells for 7 days with 10 μM acetylcholine led to a significant 0.48 fold decrease in β1-adrenergic gene expression. Previous research from our laboratory has indicated the significance of potassium channels in both lung cancer and breast cancer. Therefore, we determined if a potassium channel could be involved in these stress-induced responses. The voltage-dependent human ether à go-go (EAG) potassium channel has been shown to be important in cellular signaling, cancer progression and calcium signaling/calmodulin binding. After assay by real-time PCR, the NCI-H322 xenographs showed a significant 0.51 fold decrease in EAG gene expression, but there was no change in gene expression in the NCI-H441 xenographs. Treatment of HPL1D cells for 7 days with 10 μM acetylcholine led to a significant 0.36 fold decrease in EAG gene expression. Our data indicate social stress modulates beta-adrenergic and potassium channel-mediated signaling in lung adenocarcinoma. Supported by 1RC1CA144640 with the National Institutes of Health.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1023. doi:10.1158/1538-7445.AM2011-1023
Abstract 1027: Bcl-2 protected HNSCC cells from dasatinib-induced apoptosis
Authors: Lin Yu-Chin , Wu Meng-Hsuan , Chen Kuen-Feng , Cheng Ann-Lii , Chen Ching-Chow
Published: June 2012

Introduction: Head and neck squamous cell carcinoma (HNSCC) is a worldwide prevalent cancer with aggressive clinical courses and dismal outcomes. Incorporation of cetuximab, an antibody against epidermal growth factor receptor, had led to advance of treatment, but showed a modest efficacy. Therefore, new treatment for HNSCC is needed. Dasatinib, a Bcr-Abl and Src inhibitor, approved for treatment of chronic myeloid leukemia, was demonstrated to have activities for solid tumors. Here, we report the differential sensitivity of dasatinib for HNSCC cells and identify the possible molecular events.

Material and method: HNSCC cells including Ca9-22, HSC3, UMSCC1, FaDu, and SAS were treated with dasatinib. Cell viability, apoptosis, and underlined signal transduction were evaluated by MTT assay, flow cytometry and Western blotting, respectively.

Results: Five HNSCC cells treated with dasatinib displayed differential sensitivities. Ca9-22 and HSC3 cells are the most sensitive cells in response to dasatinib and showed significant growth inhibition and apoptosis. In contrast, FaDu and SAS cells are resistant to dasatinib-induced growth inhibition and apoptosis. UMSCC1 cells showed intermediate sensitivity to dasatinib; their growth was inhibited without induction of apoptosis. Src inhibition (Y416 dephosphorylation) was observed in all 5 cells treated with dasatinib. The growth inhibition of Ca9-22, HSC3, and UMSCC1 cells was correlated with inhibition of Akt and Erk activities, which is not observed in SAS and FaDu cells. In addition, anti-apoptotic protein bcl-2 was increased in UMSCC1, FaDu, and SAS cells, but decreased in Ca9-22 and HSC3 cells. Therefore, the increases of bcl-2 in UMSCC1 may protect cells from dasatinib-induced apoptosis.

Conclusion: Bcl-2 plays a crucial role in dasatinib-induced apoptosis in HNSCC cells, providing a new therapeutic approach to target bcl-2 in HNSCC treatment.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1027. doi:10.1158/1538-7445.AM2011-1027
Abstract 1031: Protein kinase c ∈ regulates tumor necrosis factor-α induced nuclear factor-κB signaling in prostate cancer
Authors: Garg Rachana , Benavides Fernando , Blando Jorge , Wang Hongbin , Caino Maria Cecilia , Kazanietz Marcelo G.
Published: June 2012

Protein Kinase C epsilon (PKC∈), a member of the PKC family of phorbol ester/diacylglycerol receptors, has been shown to be up-regulated in human prostate cancer specimens. As PKC∈ plays an important role in prostate cancer cell survival and cooperates with other oncogenic insults, we hypothesized that PKC∈ may regulate NF-κB signaling pathway, known to be highly dysregulated during prostate tumorigenesis. Similar to human tumors, we observed high PKC∈ overexpression in prostate cancer cell lines compared to normal immortalized RWPE-1 cells. PKC∈ depletion using siRNA or its pharmacological inhibition in LNCaP cells resulted in decreased TNFα-induced IκBα phosphorylation and degradation, as well as decreased NF-κB nuclear translocation and transactivation of NF-κB reporter activity. Conversely, significant enhancements in these TNFα-induced responses were observed in LNCaP cells upon PKC∈ overexpression using an adenoviral approach. Interestingly, TNFα treatment led to activation of PKC∈ in LNCaP cells, as analyzed by enhanced translocation from cytosolic to membrane fractions. Furthermore, TNFα-mediated PKC∈ translocation and IκBα phosphorylation were found to be dependent on phosphatidylcholine- but not phosphatidylinositol-specific phospholipase C. As determined by co-immunoprecipitation, PKC∈ associates with TNF receptor-1 (TNFR1) in response to TNFα and has important regulatory consequences in the assembly of TNFR-1 signaling complex. PKC∈ depletion by siRNA decreased the TNFα- mediated recruitment of receptor interacting protein (RIP) and TNFR-associated factor-2 (TRAF2), which are both known to mediate NF-κB activation. In accordance with the co-immunoprecipitation results, siRNA-mediated PKC∈ depletion inhibits TNFR1, TRADD, TRAF2, IKK-β- mediated NF-κB reporter activity. Furthermore, effects of PKC∈ overexpression on NF-κB transcriptional activity correlated well with the increased mRNA levels of known NF-κB regulated genes involved in cell survival, inflammation, invasion and angiogenesis (Cox2, VEGF, MMP9, and IL8). Finally, we found that in preneoplastic lesions from transgenic mice overexpressing PKC∈ in the prostate there is enhanced NF-κB activation. In summary, our study established a molecular link between PKC∈ and NF-κB in prostate cancer and suggests a prominent role for this pathway in prostate cancer cell survival.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1031. doi:10.1158/1538-7445.AM2011-1031
Abstract 1091: ShcA-mediated ERK signaling contributes to the tumor-promoting activity of TGF-beta in the presence of mutant p53
Authors: Lin Shu , Yu Lan , Yang Junhua , Sun Lu-Zhe
Published: June 2012

Transforming growth factor-beta (TGF-β) signaling has been shown to inhibit tumorigenesis at the early stage and promote metastasis at the late stage. However, biomarkers for identifying the complicated molecular alterations mediating the switch of TGF-β from a tumor suppressor to a tumor promoter still remain obscure. Published studies have shown that the presence of mutated tumor p53 can switch TGF-β to becoming tumor-promoting. However, we found that in the p53-null PC-3 prostate cancer cell line, the ectopic expression of the mutant p53 R175H (mp53) enhanced the Smad-dependent signaling, but inhibited TGF-β-induced cell migration by downregulating the active ERK. Since TGF-β is known to activate MAPK/ERK pathway to induce cell migration, EMT and survival through direct phosphorylation of adaptor protein ShcA isoform p52, we investigated how the expression of the mp53 inhibited ERK activation. We found that the expression of mp53 led to downregulation of phospho-p52ShcA and upregulation of ERK antagonist p66ShcA isoform. Interestingly, we found partial depletion of p52ShcA by using siRNA enhanced the TGF-β/Smad signaling and inhibited the TGF-β/ERK signaling in PC-3 cells and spontaneously immortalized and non-tumorigenic human mammary epithelial MCF-10A cell line, suggesting ShcA may act as an additional switcher of the TGF-β. Furthermore, reactivation of ERK by the expression of its activator, MEK1, restored active ERK level and TGF-β-induced cell migration in PC-3/mp53 cell. Those findings show that mp53 expression alone is not sufficient to promote the malignant phenotype of TGF-β in certain cells and the cooperation of mp53 and ShcA-mediated ERK signaling may switch TGF-β to be a tumor promoter.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1091. doi:10.1158/1538-7445.AM2011-1091
Abstract 1110: Differential expression of cholecystokinin receptors and their ligands in normal and neoplastic pancreas
Authors: Ortega Emily , Smith Jill P.
Published: June 2012

Background: The gastrointestinal peptide gastrin has been identified in fetal pancreas up until week 14 where it is thought to play a role in growth and differentiation. Gastrin has also been identified as an important growth factor that stimulates pancreatic cancer through the CCK-B and CCK-C receptors by an autocrine mechanism.

Hypothesis: It is hypothesized that gastrin re-expression is important to pancreatic carcinogenesis.

Methods: The mRNA from normal human pancreas tissue was isolated and endpoint RT-PCR was performed to detect RNA levels of gastrin and CCK peptide, using gastrin specific and CCK peptide specific primers, respectively. PCR products were visualized on an ethidium bromide stained gel after electrophoresis. Normal human pancreatic tissue samples were evaluated for gastrin and CCK by immunohistochemistry. Tissues were flash frozen and sectioned at a thickness of 8-10uM. Non-specific sites were blocked, followed by exposure to either gastrin or CCK antisera. Peptide presence was assessed using AF568 (Alexa Fluor) goat anti-rabbit secondary antibody.

Results: The end-point RT-PCR showed significant levels of CCK-B receptor and CCK peptide in normal pancreas samples. The gastrin end-point RT-PCR showed extremely low levels in all of the normal pancreas samples. Gastrin immunoreactivity was not detected in normal pancreas, however, staining of the positive control, an islet cell tumor, was reactive. The negative control, a GIST tumor, showed no staining as well.

Conclusions: Normal pancreas possesses the receptor CCK-B and the peptide CCK. Gastrin is not present in normal pancreatic tissues, but is detected in neoplastic pancreatic samples. Therefore, the re-expression of gastrin plays a pivotal role in the development of pancreatic cancer and could be a potential trigger to pancreatic carcinogenesis.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 1110. doi:10.1158/1538-7445.AM2011-1110