bluuebunny/crossref_metadata_2025_split huggingface dataset:
PCPH/ENTPD5 Expression Confers to Prostate Cancer Cells Resistance against Cisplatin-Induced Apoptosis through Protein Kinase Cα–Mediated Bcl-2 Stabilization
Authors: Villar Joaquín , Quadri Humair S. , Song Insun , Tomita York , Tirado Oscar M. , Notario Vicente 
Published: December 2008

Abstract
Prostate cancer (PCa) frequently develops antiapoptotic mechanisms and acquires resistance to anticancer drugs. Therefore, identifying PCa drug resistance determinants should facilitate designing more effective chemotherapeutic regimens. Recently, we described that the PCPH protein becomes highly expressed in human prostatic intraepithelial neoplasia and in PCa, and that the functional interaction between PCPH and protein kinase Cδ (PKCδ) increases the invasiveness of human PCa. Here, we report that the functional interaction between PCPH and a different PKC isoform, PKCα, confers resistance against cisplatin-induced apoptosis to PCa cells. This interaction elicits a mechanism ultimately resulting in the posttranslational stabilization and subsequent elevated expression of Bcl-2. Stable knockdown of either PCPH, mt-PCPH, or PKCα in PCa cells decreased Ser70-phosphorylated Bcl-2 and total Bcl-2 protein, thereby increasing their cisplatin sensitivity. Conversely, forced expression of the PCPH protein or, in particular, of the mt-PCPH oncoprotein increased the levels of phosphorylated PKCα concurrently with those of Ser70-phosphorylated and total Bcl-2 protein, thus promoting cisplatin resistance. Consistently, Bcl-2 knockdown sensitized PCa cells to cisplatin treatment and, more importantly, reversed the cisplatin resistance of PCa cells expressing the mt-PCPH oncoprotein. Moreover, reexpression of Bcl-2 in PCPH/mt-PCPH knockdown PCa cells reversed the cisplatin sensitization caused by PCPH or mt-PCPH down-regulation. These findings identify PCPH and mt-PCPH as important participants in the chemotherapy response of PCa cells, establish a role for PCPH-PKCα-Bcl-2 functional interactions in the drug response process, and imply that targeting PCPH expression before, or simultaneously with, chemotherapy may improve the treatment outcome for PCa patients. [Cancer Res 2009;69(1):102–10]
Adenoviral E1A Function through Myc
Authors: Chakraborty Abhishek A. , Tansey William P. 
Published: December 2008

Abstract
The study of DNA tumor viruses has been invaluable in uncovering the cellular nodes and pathways that contribute to oncogenesis. Perhaps one of the best-studied oncoproteins encoded by a DNA tumor virus is adenovirus E1A, which modifies the function of key regulatory proteins such as retinoblastoma (Rb) and the chromatin remodeling protein p400. Although the interaction of E1A with Rb has long been known to target regulation of the E2F transcription factors, the downstream target of the E1A-p400 interaction has remained elusive. We have recently reported that a critical downstream link of the E1A-p400 nexus is the oncoprotein transcription factor c-Myc. Through its interaction with p400, E1A stabilizes Myc and promotes formation of Myc-p400 complexes on chromatin, leading to activation of Myc target genes. These findings point to an important role for p400 in Myc function and reveal that E1A drives oncogenesis by tapping into two important transcriptional networks: those of E2F and Myc. [Cancer Res 2009;69(1):6–9]
A Multifactorial Signature of DNA Sequence and Polycomb Binding Predicts Aberrant CpG Island Methylation
Authors: McCabe Michael T. , Lee Eva K. , Vertino Paula M. 
Published: December 2008

AbstractAberrant CpG island methylation is associated with transcriptional silencing of regulatory genes in human cancer. Although most CpG islands remain unmethylated, a subset accrues aberrant methylation in cancer via unknown mechanisms. Previously, we showed that CpG islands differ in their intrinsic propensity towards hypermethylation. We developed a classifier (PatMAn) based on the frequencies of seven DNA sequence patterns that discriminated methylation-prone (MP) and methylation-resistant (MR) CpG islands. Here, we report on the genome-wide application and direct testing of PatMAn in cancer. Although trained on data from a cell culture model of de novo methylation involving the overexpression of DNMT1, PatMAn accurately predicted CpG islands at increased risk of hypermethylation in cancer cell lines and primary tumors. Analysis of CpG islands predicted to be MP revealed a strong association with embryonic targets of polycomb-repressive complex 2 (PRC2), indicating that PatMAn predicts not only aberrant methylation, but also PRC2 binding. A second classifier (SUPER-PatMAn) that integrates the seven PatMAn DNA patterns with SUZ12 enriched regions as a marker of PRC2 occupancy showed improved performance (prediction accuracy, 81–88%). In addition to many non-PRC2 targets, SUPER-PatMAn identified a subset of PRC2 targets that were more likely to be hypermethylated in cancer. Genome-wide, CpG islands predicted to be MP were enriched in genes known to undergo hypermethylation in cancer, genes functioning in transcriptional regulation, and components of developmental pathways. These findings show that hypermethylation of certain gene loci is controlled in part by an underlying susceptibility influenced by both local sequence context and trans-acting factors. [Cancer Res 2009;69(1):282–91]
Sequence Variants at 22q13 Are Associated with Prostate Cancer Risk
Authors: Sun Jielin , Zheng Siqun Lilly , Wiklund Fredrik , Isaacs Sarah D. , Li Ge , Wiley Kathleen E. , Kim Seong-Tae , Zhu Yi , Zhang Zheng , Hsu Fang-Chi , Turner Aubrey R. , Stattin Pär , Liu Wennuan , Kim Jin Woo , Duggan David , Carpten John , Isaacs William , Grönberg Henrik , Xu Jianfeng , Chang Bao-Li 
Published: December 2008

Abstract
To search for genetic variants that are associated with prostate cancer risk in the genome, we combined the data from our genome-wide association study (GWAS) in a population-based case-control study in Sweden with publicly available GWAS data from the Cancer Genetic Markers of Susceptibility (CGEMS) study. We limited the cases to those with aggressive disease in an attempt to identify risk variants that are associated with this most clinically relevant form of the disease. Among the most likely candidate single nucleotide polymorphisms (SNP) identified from the two GWAS, we sequentially confirmed one SNP at 22q13 in two independent study populations: the remaining subjects in Cancer of the Prostate in Sweden and a hospital-based case-control study at Johns Hopkins Hospital. Association of aggressive prostate cancer with the SNP at 22q13 was also observed in the publicly available data of four additional study populations from the second stage of the CGEMS study. In all seven study populations examined, the frequency of allele “C” of rs9623117 at 22q13 was consistently higher in aggressive cases than in controls. The combined allelic test was highly significant, with P = 5.0 × 10−7. The odds ratio (OR) of allele C for aggressive prostate cancer was estimated to be 1.18 [95% confidence interval (95% CI), 1.11-1.26]. However, the SNP was also associated with nonaggressive prostate cancer, with an estimated OR of 1.11 (95% CI, 1.04-1.19; P = 0.004). The risk-associated variants are located within the genomic region of TNRC6B, a gene involved in miRNA-mediated mRNA degradation. Additional studies are warranted to further confirm the association. [Cancer Res 2009;69(1):10–5]
DNA Methylation Markers Predict Outcome in Node-Positive, Estrogen Receptor-Positive Breast Cancer with Adjuvant Anthracycline-Based Chemotherapy
Authors: Hartmann Oliver , Spyratos Frédérique , Harbeck Nadia , Dietrich Dimo , Fassbender Anne , Schmitt Manfred , Eppenberger-Castori Serenella , Vuaroqueaux Vincent , Lerebours Florence , Welzel Katrin , Maier Sabine , Plum Achim , Niemann Stephan , Foekens John A. , Lesche Ralf , Martens John W.M. 
Published: December 2008

Abstract
Purpose: We have shown that DNA methylation of the PITX2 gene predicts risk of distant recurrence in steroid hormone receptor-positive, node-negative breast cancer. Here, we present results from a multicenter study investigating whether PITX2 and other candidate DNA methylation markers predict outcome in node-positive, estrogen receptor-positive, HER-2-negative breast cancer patients who received adjuvant anthracycline-based chemotherapy.
Experimental Design: Using a microarray platform, we analyzed DNA methylation in regulatory regions of PITX2 and 60 additional candidate genes in 241 breast cancer specimens. Using Cox regression analysis, we assessed the predictive power of the individual marker/marker panel candidates. Clinical endpoints were time to distant metastasis, disease-free survival, and overall survival. A nested bootstrap/cross-validation strategy was applied to identify and validate marker panels.
Results: DNA methylation of PITX2 and 14 other genes was correlated with clinical outcome. In multivariate models, each methylation marker added significant information to established clinical factors. A four-marker panel including PITX2, BMP4, FGF4, and C20orf55 was identified that resulted in improvement of outcome prediction compared with PITX2 alone.
Conclusions: This study provides further evidence for the PITX2 biomarker, which has now been successfully confirmed to predict outcome among different breast cancer patient populations. We further identify new DNA methylation biomarkers, three of which can be combined into a panel with PITX2 to increase the outcome prediction performance in our anthracycline-treated primary breast cancer population. Our results show that a well-defined panel of DNA methylation markers enables outcome prediction in lymph node-positive, HER-2-negative breast cancer patients treated with anthracycline-based chemotherapy.
Cytoplasmic Sequestration of p27 via AKT Phosphorylation in Renal Cell Carcinoma
Authors: Kim Jinhee , Jonasch Eric , Alexander Angela , Short John D. , Cai Shengli , Wen Sijin , Tsavachidou Dimitra , Tamboli Pheroze , Czerniak Bogdan A. , Do Kim Anh , Wu Kevin J. , Marlow Laura A. , Wood Christopher G. , Copland John A. , Walker Cheryl Lyn 
Published: December 2008

Abstract
Purpose: p27 localization and expression has prognostic and predictive value in cancer. Little is known regarding expression patterns of p27 in renal cell carcinoma (RCC) or how p27 participates in disease progression or response to therapy.
Experimental Design: RCC-derived cell lines, primary tumors, and normal renal epithelial cells were analyzed for p27 expression, phosphorylation (T157 of the NLS), and subcellular localization. RCC-derived cell lines were treated with phosphatidylinositol 3-kinase (PI3K) and mammalian target of rapamycin (mTOR) inhibitors and effects on p27 localization were assessed. The potential contribution of cytoplasmic p27 to resistance to apoptosis was also evaluated.
Results: p27 was elevated in tumors compared with matched controls, and cytoplasmic mislocalization of p27 was associated with increasing tumor grade. Cytoplasmic localization of p27 correlated with phosphorylation at T157, an AKT phosphorylation site in the p27 NLS. In RCC cell lines, activated PI3K/AKT signaling was accompanied by mislocalization of p27. AKT activation and phosphorylation of p27 was associated with resistance to apoptosis, and small interfering RNA knockdown of p27 or relocalization to the nucleus increased apoptosis in RCC cells. Treatment with the PI3K inhibitors LY294002 or wortmannin resulted in nuclear relocalization of p27, whereas mTOR inhibition by rapamycin did not.
Conclusions: In RCC, p27 is phosphorylated at T157 of the NLS, with increasing tumor grade associated with cytoplasmic p27. PI3K inhibition (which reduces AKT activity) reduces T157 phosphorylation and induces nuclear relocalization of p27, whereas mTOR inhibition does not. Clinical testing of these findings may provide a rational approach for use of mTOR and PI3K/AKT pathway inhibitors in patients with RCC.
Imaging Intratumoral Convection: Pressure-Dependent Enhancement in Chemotherapeutic Delivery to Solid Tumors
Authors: Gade Terence P.F. , Buchanan Ian M. , Motley Matthew W. , Mazaheri Yousef , Spees William M. , Koutcher Jason A. 
Published: December 2008

AbstractPurpose: Low–molecular weight (LMW) chemotherapeutics are believed to reach tumors through diffusion across capillary beds as well as membrane transporters. Unexpectedly, the delivery of these agents seems to be augmented by reductions in tumor interstitial fluid pressure, an effect typically associated with high–molecular weight molecules that reach tumors principally through convection. We investigated the hypothesis that improved intratumoral convection can alter tumor metabolism and enhance the delivery of a LMW chemotherapeutic agent to solid tumors.Experimental Design: For this purpose, we applied 31P/19F magnetic resonance spectroscopy (MRS) and magnetic resonance spectroscopic imaging (MRSI) to examine the influence of type I collagenase on tumor bioenergetics and the delivery of 5-fluorouracil (5FU) to HT29 human colorectal tumors grown s.c. in mice.Results: Collagenase effected a 34% reduction in tumor interstitial fluid pressure with an attendant disintegration of intratumoral collagen. Neither mice-administered collagenase nor controls receiving PBS showed changes in 31phosphorus MRS–measured tumor bioenergetics; however, a time-dependent increase in the content of extracellular inorganic phosphate (Pie) was observed in tumors of collagenase-treated animals. 31Phosphorus MRSI showed that this increase underscored a more homogeneous distribution of Pie in tumors of experimental mice. 19Fluorine MRS showed that these changes were associated with a 50% increase in 5FU uptake in tumors of experimental versus control animals; however, this increase resulted in an increase in 5FU catabolites rather than fluoronucleotide intermediates that are required for subsequent cytotoxicity.Conclusions: These data indicate that the modulation of convective flow within tumors can improve the delivery of (LMW) chemotherapeutics and show the potential role for noninvasive imaging of this process in vivo.
Intratumoral Immune Cell Infiltrates, FoxP3, and Indoleamine 2,3-Dioxygenase in Patients with Melanoma Undergoing CTLA4 Blockade
Authors: Ribas Antoni , Comin-Anduix Begoña , Economou James S. , Donahue Timothy R. , de la Rocha Pilar , Morris Lilah F. , Jalil Jason , Dissette Vivian B. , Shintaku Itsushi Peter , Glaspy John A. , Gomez-Navarro Jesus , Cochran Alistair J. 
Published: December 2008

Abstract
Purpose: CTL-associated antigen 4 (CTLA4)-blocking monoclonal antibodies induce long-term regression of metastatic melanoma in some patients, but the exact mechanism is unknown. In this study, biopsies of selected accessible tumor lesions from patients treated with tremelimumab were examined to further elucidate the mechanism of its antitumor activity.
Experimental Design: Fifteen tumor biopsies from 7 patients who had been treated with tremelimumab (CP-675,206) were collected. Samples were analyzed for melanoma markers, immune cell subset markers, the presence of the T regulatory-specific transcription factor FoxP3 and the immunosuppressive enzyme indoleamine 2,3-dioxygenase (IDO).
Results: Clinically responding lesions had diffuse intratumoral infiltrates of CD8+ T cells that were markedly increased in cases where comparison with a baseline biopsy was available. Nonregressing lesions had sparse, patchy CD8+ intratumoral infiltrates. Patients with regressing lesions had an increased frequency of CD8+ cells with or without a concomitant increase in CD4+ cells. Two of 3 responding patients with paired samples showed a slight increase in the number of FoxP3+ cells in the postdosing biopsies. In patients with regressing lesions who had paired samples, the intensity of IDO staining in macrophages and/or melanoma cells showed no clear pattern of change postdosing.
Conclusions: Administration of tremelimumab was associated with massive intratumoral infiltrates of CD8+ CTLs in patients with regressing tumors but had varying effects on intratumoral infiltrates of CD4+ and FoxP3+ cells or intratumoral expression of IDO.
Population Pharmacokinetic/Pharmacodynamic Analyses of Pemetrexed and Neutropenia: Effect of Vitamin Supplementation and Differences between Japanese and Western Patients
Authors: Latz Jane E. , Schneck Karen Lee , Nakagawa Kazuhiko , Miller Mary Alice , Takimoto Chris H. 
Published: December 2008

Abstract
Purpose: The objectives of the analysis were to characterize the time course of neutropenia after pemetrexed administration using an established semimechanistic-physiologic model, characterize the relationship between pemetrexed exposure and neutropenia, and describe differences in neutropenic response by vitamin supplementation status and between Japanese and Western patients.
Experimental Design: An eight-compartment population pharmacokinetic/pharmacodynamic model was used to describe the absolute neutrophil count (ANC)-time profile (neutropenic response) following pemetrexed doses of 300 to 1,400 mg/m2 administered every 21 days. The analyses pooled data from 13 studies including 279 patients (161 supplemented with oral folic acid and intramuscular vitamin B12, and 118 unsupplemented; 248 Western and 31 Japanese) who received 857 treatment cycles.
Results: Vitamin supplementation status, ethnic origin, and drug exposure were the dominant predictors of neutropenic response. Vitamin supplementation diminishes neutropenic response to pemetrexed. Model-predicted ANC nadirs for the “typical” Western patient receiving 500 mg/m2 pemetrexed ± vitamin supplementation were 2.74 × 109/L and 1.70 × 109/L, respectively. Japanese patients had a less pronounced neutropenic response to pemetrexed relative to Western patients. The model-predicted ANC nadir for Japanese patients receiving 500 mg/m2 pemetrexed with vitamin supplementation was 2.66 × 109/L. Values for the 1,000 mg/m2 dose with vitamin supplementation were 1.91 × 109/L and 1.34 × 109/L for Japanese and Western patients, respectively. Increased albumin, decreased cystathionine, and decreased body surface area were also associated with increased neutropenic response.
Conclusions: The neutropenic response to higher pemetrexed doses administered with vitamin supplementation is tolerable. All other factors equal, Japanese patients have a lesser neutropenic response to pemetrexed relative to Western patients.
BMS-536924 Reverses IGF-IR-Induced Transformation of Mammary Epithelial Cells and Causes Growth Inhibition and Polarization of MCF7 Cells
Authors: Litzenburger Beate C. , Kim Hyun-Jung , Kuiatse Isere , Carboni Joan M. , Attar Ricardo M. , Gottardis Marco M. , Fairchild Craig R. , Lee Adrian V. 
Published: December 2008

Abstract
Purpose: This study aimed to test the ability of a new insulin-like growth factor receptor (IGF-IR) tyrosine kinase inhibitor, BMS-536924, to reverse the ability of constitutively active IGF-IR (CD8-IGF-IR) to transform MCF10A cells, and to examine the effect of the inhibitor on a range of human breast cancer cell lines.
Experimental Design: CD8-IGF-IR-MCF10A cells were grown in monolayer culture, three-dimensional (3D) culture, and as xenografts, and treated with BMS-536924. Proliferation, cell cycle, polarity, and apoptosis were measured. Twenty-three human breast cancer cell lines were treated in monolayer culture with BMS-536924, and cell viability was measured. MCF7, MDA-MB-231, and MDA-MB-435 were treated with BMS-536924 in monolayer and 3D culture, and proliferation, migration, polarity, and apoptosis were measured.
Results: Treatment of CD8-IGF-IR-MCF10A cells grown in 3D culture with BMS-536924 caused a blockade of proliferation, restoration of apical-basal polarity, and enhanced apoptosis, resulting in a partial phenotypic reversion to normal acini. In monolayer culture, BMS-536924 induced a dose-dependent inhibition of proliferation, with an accumulation of cells in G0/G1,, and completely blocked CD8-IGF-IR–induced migration, invasion, and anchorage-independent growth. CD8-IGF-IR-MCF10A xenografts treated with BMS-536924 (100 mg/kg/day) showed a 76% reduction in xenograft volume. In a series of 23 human breast cancer cell lines, BMS-536924 inhibited monolayer proliferation of 16 cell lines. Most strikingly, treatment of MCF7 cells grown in 3D culture with BMS-536924 caused blockade of proliferation, and resulted in the formation of hollow polarized lumen.
Conclusions: These results show that the new small molecule BMS-536924 is an effective inhibitor of IGF-IR, causing a reversion of an IGF-IR–mediated transformed phenotype.
Lenalidomide and Rituximab in Waldenstrom's Macroglobulinemia
Authors: Treon Steven P. , Soumerai Jacob D. , Branagan Andrew R. , Hunter Zachary R. , Patterson Christopher J. , Ioakimidis Leukothea , Chu Luis , Musto Paul , Baron Ari D. , Nunnink Johannes C. , Kash Joseph J. , Terjanian Terenig O. , Hyman Paul M. , Nawfel Elena L. , Sharon David J. , Munshi Nikhil C. , Anderson Kenneth C. 
Published: December 2008

Abstract
Purpose: Thalidomide and its more potent immunomodulatory derivative lenalidomide enhance rituximab-mediated antibody-dependent cell-mediated cytotoxicity. We therefore evaluated lenalidomide and rituximab in symptomatic Waldenstrom's macroglobulinemia (WM) patients naive to either agent.
Experimental Design: Intended therapy consisted of 48 weeks of lenalidomide (25 mg/d for 3 weeks and then 1 week off) along with rituximab (375 mg/m2/wk) dosed on weeks 2 to 5 and 13 to 16. Sixteen patients were enrolled, 12 of whom were previously untreated.
Results: Unexpectedly, we observed an acute decrease in hematocrit in 13 of 16 patients (median hematocrit decrease, 4.8%), which was attributable to lenalidomide patients and which led to cessation of further enrollment on this study. Lenalidomide-related anemia was observed even at doses as low as 5 mg/d and occurred in the absence of hemolysis or other cytopenias. The overall response and major response (&lt;50% decrease in serum IgM) rates were 50% and 25%, respectively, on an intent-to-treat basis. With a median follow-up of 31.3 months, 4 of 8 responding patients have progressed with a median time to progression of 18.9 months.
Conclusion: Lenalidomide produces unexpected but clinically significant acute anemia in patients with WM. In comparison with our previous study with thalidomide and rituximab in an analogous patient population, the responses achieved in WM patients with lenalidomide and rituximab appear less favorable.