bluuebunny/crossref_metadata_2025 huggingface dataset:
Adipose-Derived Stem Cells in Crohn's Rectovaginal Fistula
Authors: García-Olmo D. , Herreros D. , De-La-Quintana P. , Guadalajara H. , Trébol J. , Georgiev-Hristov T. , García-Arranz M.
Published: March 2010

Therapeutic options for recto-vaginal fistula in the setting of Crohn's disease are limited and many data are available in the literature. The manuscript describes the history of a patient who has been the pioneer of our Clinical Trials in treating this disease in fistulizing Crohn's disease environment. We believe it is the first time that a patient with this disease has been treated by adipose-derived stem cells in allogeneic form. The conclusion of our study with Mary is that the use of mesenchymal stem cells derived from adipose tissue is secure, either in autologous or allogeneic form. Furthermore, we have proved that if we use multi-dose and multiple applications on a patient, it does not produce any adverse effect, which confirms us the safety of using these cells in patients at least in the fistulizing Crohn's disease environment.
Multiview Shooting Geometry for Multiscopic Rendering with Controlled Distortion
Authors: Prévoteau J. , Chalençon-Piotin S. , Debons D. , Lucas L. , Remion Y.
Published: March 2010

A fundamental element of stereoscopic and/or autostereoscopic image production is the geometrical analysis of the shooting and viewing conditions in order to obtain a qualitative 3D perception experience. This paper firstly compares the perceived depth with the shot scene depth from the viewing and shooting geometries for a couple of shooting and rendering devices. This yields a depth distortion model whose parameters are expressed from the geometrical characteristics of shooting and rendering devices. Secondly, these expressions are inverted in order to design convenient shooting layouts yielding chosen distortions on specific rendering devices. Thirdly, this design scheme provides three shooting technologies (3D computer graphics software, photo rail, and camera box system) producing qualitative 3D content for various kinds of scenes (real or virtual, still or animated), complying with any prechosen distortion when rendered on any specific multiscopic technology or device formerly specified.
Blockade of Mitogen-Activated Protein Kinase/Extracellular Signal-Regulated Kinase Kinase and Murine Double Minute Synergistically Induces Apoptosis in Acute Myeloid Leukemia via BH3-Only Proteins Puma and Bim
Authors: Zhang Weiguo , Konopleva Marina , Burks Jared K. , Dywer Karen C. , Schober Wendy D. , Yang Jer-Yen , McQueen Teresa J. , Hung Mien-Chie , Andreeff Michael
Published: March 2010

Molecular aberrations of the Ras/Raf/mitogen-activated protein kinase/extracellular signal-regulated kinase (ERK) kinase (MEK)/ERK and/or Murine double minute (MDM2)/p53 signaling pathways have been reported in 80% and 50% of primary acute myeloid leukemia (AML) samples and confer poor outcome. In this study, antileukemic effects of combined MEK inhibition by AZD6244 and nongenotoxic p53 activation by MDM2 antagonist Nutlin-3a were investigated. Simultaneous blockade of MEK and MDM2 signaling by AZD6244 and Nutlin-3a triggered synergistic proapoptotic responses in AML cell lines [combination index (CI) = 0.06 ± 0.03 and 0.43 ± 0.03 in OCI/AML3 and MOLM13 cells, respectively] and in primary AML cells (CI = 0.52 ± 0.01). Mechanistically, the combination upregulated levels of BH3-only proteins Puma and Bim, in part via transcriptional upregulation of the FOXO3a transcription factor. Suppression of Puma and Bim by short interfering RNA rescued OCI/AML3 cells from AZD/Nutlin-induced apoptosis. These results strongly indicate the therapeutic potential of combined MEK/MDM2 blockade in AML and implicate Puma and Bim as major regulators of AML cell survival. Cancer Res; 70(6); 2424–34
Transcriptional Pathway Signatures Predict MEK Addiction and Response to Selumetinib (AZD6244)
Authors: Dry Jonathan R. , Pavey Sandra , Pratilas Christine A. , Harbron Chris , Runswick Sarah , Hodgson Darren , Chresta Christine , McCormack Rose , Byrne Natalie , Cockerill Mark , Graham Alexander , Beran Garry , Cassidy Andrew , Haggerty Carolyn , Brown Helen , Ellison Gillian , Dering Judy , Taylor Barry S. , Stark Mitchell , Bonazzi Vanessa , Ravishankar Sugandha , Packer Leisl , Xing Feng , Solit David B. , Finn Richard S. , Rosen Neal , Hayward Nicholas K. , French Tim , Smith Paul D.
Published: March 2010

Selumetinib (AZD6244, ARRY-142886) is a selective, non–ATP-competitive inhibitor of mitogen-activated protein/extracellular signal–regulated kinase kinase (MEK)-1/2. The range of antitumor activity seen preclinically and in patients highlights the importance of identifying determinants of response to this drug. In large tumor cell panels of diverse lineage, we show that MEK inhibitor response does not have an absolute correlation with mutational or phospho-protein markers of BRAF/MEK, RAS, or phosphoinositide 3-kinase (PI3K) activity. We aimed to enhance predictivity by measuring pathway output through coregulated gene networks displaying differential mRNA expression exclusive to resistant cell subsets and correlated to mutational or dynamic pathway activity. We discovered an 18-gene signature enabling measurement of MEK functional output independent of tumor genotype. Where the MEK pathway is activated but the cells remain resistant to selumetinib, we identified a 13-gene signature that implicates the existence of compensatory signaling from RAS effectors other than PI3K. The ability of these signatures to stratify samples according to functional activation of MEK and/or selumetinib sensitivity was shown in multiple independent melanoma, colon, breast, and lung tumor cell lines and in xenograft models. Furthermore, we were able to measure these signatures in fixed archival melanoma tumor samples using a single RT-qPCR–based test and found intergene correlations and associations with genetic markers of pathway activity to be preserved. These signatures offer useful tools for the study of MEK biology and clinical application of MEK inhibitors, and the novel approaches taken may benefit other targeted therapies. Cancer Res; 70(6); 2264–73
BRD7, a Subunit of SWI/SNF Complexes, Binds Directly to BRCA1 and Regulates BRCA1-Dependent Transcription
Authors: Harte Mary T. , O'Brien Garrett J. , Ryan Niamh M. , Gorski Julia J. , Savage Kienan I. , Crawford Nyree T. , Mullan Paul B. , Harkin D. Paul
Published: March 2010

We carried out a yeast two-hybrid screen using a BRCA1 bait composed of amino acids 1 to 1142 and identified BRD7 as a novel binding partner of BRCA1. This interaction was confirmed by coimmunoprecipitation of endogenous BRCA1 and BRD7 in T47D and HEK-293 cells. BRD7 is a bromodomain containing protein, which is a subunit of PBAF-specific Swi/Snf chromatin remodeling complexes. To determine the functional consequences of the BRCA1-BRD7 interaction, we investigated the role of BRD7 in BRCA1-dependent transcription using microarray-based expression profiling. We found that a variety of targets were coordinately regulated by BRCA1 and BRD7, such as estrogen receptor α (ERα). Depletion of BRD7 or BRCA1 in either T47D or MCF7 cells resulted in loss of expression of ERα at both the mRNA and protein level, and this loss of ERα was reflected in resistance to the antiestrogen drug fulvestrant. We show that BRD7 is present, along with BRCA1 and Oct-1, on the ESR1 promoter (the gene which encodes ERα). Depletion of BRD7 prevented the recruitment of BRCA1 and Oct-1 to the ESR1 promoter; however, it had no effect on the recruitment of the other Swi/Snf subunits BRG1, BAF155, and BAF57 or on RNA polymerase II recruitment. These results support a model whereby the regulation of ERα transcription by BRD7 is mediated by its recruitment of BRCA1 and Oct-1 to the ESR1 promoter. Cancer Res; 70(6); 2538–47
Oncolytic Viral Therapy for Prostate Cancer: Efficacy of Reovirus as a Biological Therapeutic
Authors: Thirukkumaran Chandini M. , Nodwell Michael J. , Hirasawa Kensuke , Shi Zhong-Qiao , Diaz Roman , Luider Joanne , Johnston Randal N. , Forsyth Peter A. , Magliocco Anthony M. , Lee Patrick , Nishikawa Sandra , Donnelly Bryan , Coffey Matt , Trpkov Kiril , Fonseca Kevin , Spurrell Jason , Morris Don G.
Published: March 2010

Reovirus is a nonattenuated double-stranded RNA virus that exploits aberrant signaling pathways allowing selective cytotoxicity against multiple cancer histologies. The use of reovirus as a potential treatment modality for prostate cancer has not previously been described, and in this study evidence of in vitro and in vivo activity against prostate cancer was seen both in preclinical models and in six patients. The human prostate carcinoma cell lines PC-3, LN-CaP, and DU-145 exposed to replication-competent reovirus showed evidence of infection as illustrated by viral protein synthesis, cytopathic effect, and release of viral progeny. This oncolytic effect was found to be manifested through apoptosis, as DNA fragmentation, Apo 2.7 expression, Annexin V binding, and poly(ADP-ribose) polymerase cleavage were observed in live reovirus-infected cells, but not in uninfected or dead virus–treated cells. In vivo, hind flank severe combined immunodeficient/nonobese diabetic murine xenograft showed reduction in tumor size when treated with even a single intratumoral injection of reovirus. Finally, intralesional reovirus injections into a cohort of six patients with clinically organ-confined prostate cancer resulted in minimal side effects and evidence of antitumor activity. Histologic analysis after prostatectomy found a significant CD8 T-cell infiltration within the reovirus-injected areas as well as evidence of increased caspase-3 activity. These findings suggest that reovirus therapy may provide a promising novel treatment for prostate cancer and also imply a possible role for viral immune targeting of tumor. Cancer Res; 70(6); 2435–44
Novel STAT3 Phosphorylation Inhibitors Exhibit Potent Growth-Suppressive Activity in Pancreatic and Breast Cancer Cells
Authors: Lin Li , Hutzen Brian , Zuo Mingxin , Ball Sarah , Deangelis Stephanie , Foust Elizabeth , Pandit Bulbul , Ihnat Michael A. , Shenoy Satyendra S. , Kulp Samuel , Li Pui-Kai , Li Chenglong , Fuchs James , Lin Jiayuh
Published: March 2010

The constitutive activation of signal transducer and activator of transcription 3 (STAT3) is frequently detected in most types of human cancer where it plays important roles in survival, drug resistance, angiogenesis, and other functions. Targeting constitutive STAT3 signaling is thus an attractive therapeutic approach for these cancers. We have recently developed novel small-molecule STAT3 inhibitors, known as FLLL31 and FLLL32, which are derived from curcumin (the primary bioactive compound of turmeric). These compounds are designed to bind selectively to Janus kinase 2 and the STAT3 Src homology-2 domain, which serve crucial roles in STAT3 dimerization and signal transduction. Here we show that FLLL31 and FLLL32 are effective inhibitors of STAT3 phosphorylation, DNA-binding activity, and transactivation in vitro, leading to the impediment of multiple oncogenic processes and the induction of apoptosis in pancreatic and breast cancer cell lines. FLLL31 and FLLL32 also inhibit colony formation in soft agar and cell invasion and exhibit synergy with the anticancer drug doxorubicin against breast cancer cells. In addition, we show that FLLL32 can inhibit the induction of STAT3 phosphorylation by IFNα and interleukin-6 in breast cancer cells. We also show that administration of FLLL32 can inhibit tumor growth and vascularity in chicken embryo xenografts as well as substantially reduce tumor volumes in mouse xenografts. Our findings highlight the potential of these new compounds and their efficacy in targeting pancreatic and breast cancers that exhibit constitutive STAT3 signaling. Cancer Res; 70(6); 2445–54
Plasma Cytokine and Angiogenic Factor Profiling Identifies Markers Associated with Tumor Shrinkage in Early-Stage Non–Small Cell Lung Cancer Patients Treated with Pazopanib
Authors: Nikolinakos Petros G. , Altorki Nasser , Yankelevitz David , Tran Hai T. , Yan Shaoyu , Rajagopalan Dilip , Bordogna Walter , Ottesen Lone H. , Heymach John V.
Published: March 2010

There is an unmet need for pharmacodynamic and predictive biomarkers for antiangiogenic agents. Recent studies have shown that soluble vascular endothelial growth factor receptor 2 (sVEGFR2), VEGF, and several other soluble factors may be modulated by VEGF pathway inhibitors. We conducted a broad profiling of cytokine and angiogenic factors (CAF) to investigate the relationship between baseline CAF levels, CAF changes during treatment, and tumor shrinkage in early-stage non–small cell lung cancer (NSCLC) patients treated with pazopanib, an oral angiogenesis inhibitor targeting VEGFR, platelet-derived growth factor receptor, and c-kit. Plasma samples were collected before treatment and on the last day of therapy from 33 patients with early-stage NSCLC participating in a single-arm phase II trial. Levels of 31 CAFs were measured by suspension bead multiplex assays or ELISA and correlated with change in tumor volume. Pazopanib therapy was associated with significant changes of eight CAFs; sVEGFR2 showed the largest decrease, whereas placental growth factor underwent the largest increase. Increases were also observed in stromal cell–derived factor-1α, IP-10, cutaneous T-cell–attracting chemokine, monokine induced by IFN-γ, tumor necrosis factor–related apoptosis-inducing ligand, and IFN-α. Posttreatment changes in plasma sVEGFR2 and interleukin (IL)-4 significantly correlated with tumor shrinkage. Baseline levels of 11 CAFs significantly correlated with tumor shrinkage, with IL-12 showing the strongest association. Using multivariate classification, a baseline CAF signature consisting of hepatocyte growth factor and IL-12 was associated with tumor response to pazopanib and identified responding patients with 81% accuracy. These data suggest that CAF profiling may be useful for identifying patients likely to benefit from pazopanib, and merit further investigation in clinical trials. Cancer Res; 70(6); 2171–9
MicroRNA-375 Is Downregulated in Gastric Carcinomas and Regulates Cell Survival by Targeting PDK1 and 14-3-3ζ
Authors: Tsukamoto Yoshiyuki , Nakada Chisato , Noguchi Tsuyoshi , Tanigawa Masato , Nguyen Lam Tung , Uchida Tomohisa , Hijiya Naoki , Matsuura Keiko , Fujioka Toshio , Seto Masao , Moriyama Masatsugu
Published: March 2010

We investigated expression profiles of microRNA (miRNA) in gastric carcinomas by use of a miRNA microarray platform covering a total of 470 human miRNAs. We identified 39 differentially expressed miRNAs in gastric carcinoma, of which six were significantly downregulated and the other 33 were upregulated. We found that miRNA-375 (miR-375) was the most downregulated and that its ectopic expression in gastric carcinoma cells markedly reduced cell viability via the caspase-mediated apoptosis pathway. Interestingly, we found that expression of miR-375 inhibited expression of PDK1, which is a direct target of miR-375, followed by suppression of Akt phosphorylation. Further analysis by gene expression microarray revealed that 14-3-3ζ, a potent antiapoptotic gene, was significantly downregulated at both the mRNA and protein levels in cells transfected with miR-375. The activity of a luciferase reporter containing the miR-375 binding sequence at the 3′ untranslated region (UTR) of 14-3-3ζ mRNA was repressed by the ectopic expression of miR-375, suggesting that miR-375 targets the 3′ UTR of 14-3-3ζ. In addition, knockdown of either PDK1 or 14-3-3ζ in gastric carcinoma cells induced caspase activation, which was also observed in miR-375–transfected cells, suggesting that miR-375 may exert its proapoptotic function, at least in part, through the downregulation of PDK1 and 14-3-3ζ. Taken together, we propose that miR-375 is a candidate tumor suppressor miRNA in gastric carcinoma. Cancer Res; 70(6); 2339–49
Combined Delivery and Magnetic Resonance Imaging of Neural Cell Adhesion Molecule–Targeted Doxorubicin-Containing Liposomes in Experimentally Induced Kaposi's Sarcoma
Authors: Grange Cristina , Geninatti-Crich Simonetta , Esposito Giovanna , Alberti Diego , Tei Lorenzo , Bussolati Benedetta , Aime Silvio , Camussi Giovanni
Published: March 2010

Specific targeting of tumors by combined delivery of drugs and of imaging agents represents an attractive strategy for treatment of cancer. The aim of the present study was to investigate whether neural cell adhesion molecule (NCAM)–targeted liposomes may enhance drug delivery and allow magnetic resonance imaging (MRI) in a severe combined immunodeficient mouse model of NCAM-positive Kaposi's sarcoma. NCAM-binding peptide–coated liposomes loaded with both doxorubicin and a lipophilic gadolinium (Gd) derivative were generated. NCAM-targeted liposomes induced an enhanced in vitro doxorubicin internalization within Kaposi's cells as detected by MRI with respect to untargeted polyethylene glycol liposomes. Internalization resulted in enhanced apoptosis. In vivo weekly administration of NCAM-targeted liposomes containing 5 mg/kg doxorubicin for 4 consecutive weeks induced a significant reduction of tumor mass and vascularization and enhanced cell necrosis and apoptosis with respect to untargeted liposomes. These effects were associated with an enhanced concentration of doxorubicin within the tumor and a reduced systemic toxicity of doxorubicin. By electron microscopy, NCAM-targeted liposomes were detected mainly within tumor cells whereas the untargeted liposomes were mainly accumulated in the extracellular space. Gd-labeled liposomes allowed the MRI visualization of drug delivery in the tumor region. The intensity of MRI signal was partially hampered by the “quenching” of the attainable relaxation enhancement on endosomal entrapment of the Gd-labeled liposomes. In conclusion, targeting NCAM may be a suitable strategy for specific drug delivery and imaging by liposomes in NCAM-expressing tumors. Moreover, treatment with NCAM-targeted liposomes showed enhanced therapeutic effect and reduced toxicity with respect to untargeted liposomes. Cancer Res; 70(6); 2180–90
A Susceptibility Locus on Chromosome 6q Greatly Increases Lung Cancer Risk among Light and Never Smokers
Authors: Amos Christopher I. , Pinney Susan M. , Li Yafang , Kupert Elena , Lee Juwon , de Andrade Mariza A. , Yang Ping , Schwartz Ann G. , Fain Pam R. , Gazdar Adi , Minna John , Wiest Jonathan S. , Zeng Dong , Rothschild Henry , Mandal Diptasri , You Ming , Coons Teresa , Gaba Colette , Bailey-Wilson Joan E. , Anderson Marshall W.
Published: March 2010

Cigarette smoking is the major cause for lung cancer, but genetic factors also affect susceptibility. We studied families that included multiple relatives affected by lung cancer. Results from linkage analysis showed strong evidence that a region of chromosome 6q affects lung cancer risk. To characterize the effects that this region of chromosome 6q region has on lung cancer risk, we identified a haplotype that segregated with lung cancer. We then performed Cox regression analysis to estimate the differential effects that smoking behaviors have on lung cancer risk according to whether each individual carried a risk-associated haplotype or could not be classified and was assigned unknown haplotypic status. We divided smoking exposures into never smokers, light smokers (<20 pack-years), moderate smokers (20 to <40 pack-years), and heavy smokers (≥40 pack-years). Comparing results according to smoking behavior stratified by carrier status, compared with never smokers, there was weakly increasing risk for increasing smoking behaviors, with the hazards ratios being 3.44, 4.91, and 5.18, respectively, for light, moderate, or heavy smokers, whereas among the individuals from families without the risk haplotype, the risks associated with smoking increased strongly with exposure, the hazards ratios being, respectively, 4.25, 9.17, and 11.89 for light, moderate, and heavy smokers. The never smoking carriers had a 4.71-fold higher risk than the never smoking individuals without known risk haplotypes. These results identify a region of chromosome 6q that increases risk for lung cancer and that confers particularly higher risks to never and light smokers. Cancer Res; 70(6); 2359–67
LYN Is a Mediator of Epithelial-Mesenchymal Transition and a Target of Dasatinib in Breast Cancer
Authors: Choi Yoon-La , Bocanegra Melanie , Kwon Mi Jeong , Shin Young Kee , Nam Seok Jin , Yang Jung-Hyun , Kao Jessica , Godwin Andrew K. , Pollack Jonathan R.
Published: March 2010

Epithelial-mesenchymal transition (EMT), a switch of polarized epithelial cells to a migratory, fibroblastoid phenotype, is considered a key process driving tumor cell invasiveness and metastasis. Using breast cancer cell lines as a model system, we sought to discover gene expression signatures of EMT with clinical and mechanistic relevance. A supervised comparison of epithelial and mesenchymal breast cancer lines defined a 200-gene EMT signature that was prognostic across multiple breast cancer cohorts. The immunostaining of LYN, a top-ranked EMT signature gene and Src-family tyrosine kinase, was associated with significantly shorter overall survival (P = 0.02) and correlated with the basal-like (“triple-negative”) phenotype. In mesenchymal breast cancer lines, RNAi-mediated knockdown of LYN inhibited cell migration and invasion, but not proliferation. Dasatinib, a dual-specificity tyrosine kinase inhibitor, also blocked invasion (but not proliferation) at nanomolar concentrations that inhibit LYN kinase activity, suggesting that LYN is a likely target and that invasion is a relevant end point for dasatinib therapy. Our findings define a prognostically relevant EMT signature in breast cancer and identify LYN as a mediator of invasion and a possible new therapeutic target (and theranostic marker for dasatinib response), with particular relevance to clinically aggressive basal-like breast cancer. Cancer Res; 70(6); 2296–306
An ErbB3 Antibody, MM-121, Is Active in Cancers with Ligand-Dependent Activation
Authors: Schoeberl Birgit , Faber Anthony C. , Li Danan , Liang Mei-Chih , Crosby Katherine , Onsum Matthew , Burenkova Olga , Pace Emily , Walton Zandra , Nie Lin , Fulgham Aaron , Song Youngchul , Nielsen Ulrik B. , Engelman Jeffrey A. , Wong Kwok-Kin
Published: March 2010

ErbB3 is a critical activator of phosphoinositide 3-kinase (PI3K) signaling in epidermal growth factor receptor (EGFR; ErbB1), ErbB2 [human epidermal growth factor receptor 2 (HER2)], and [hepatocyte growth factor receptor (MET)] addicted cancers, and reactivation of ErbB3 is a prominent method for cancers to become resistant to ErbB inhibitors. In this study, we evaluated the in vivo efficacy of a therapeutic anti-ErbB3 antibody, MM-121. We found that MM-121 effectively blocked ligand-dependent activation of ErbB3 induced by either EGFR, HER2, or MET. Assessment of several cancer cell lines revealed that MM-121 reduced basal ErbB3 phosphorylation most effectively in cancers possessing ligand-dependent activation of ErbB3. In those cancers, MM-121 treatment led to decreased ErbB3 phosphorylation and, in some instances, decreased ErbB3 expression. The efficacy of single-agent MM-121 was also examined in xenograft models. A machine learning algorithm found that MM-121 was most effective against xenografts with evidence of ligand-dependent activation of ErbB3. We subsequently investigated whether MM-121 treatment could abrogate resistance to anti-EGFR therapies by preventing reactivation of ErbB3. We observed that an EGFR mutant lung cancer cell line (HCC827), made resistant to gefitinib by exogenous heregulin, was resensitized by MM-121. In addition, we found that a de novo lung cancer mouse model induced by EGFR T790M-L858R rapidly became resistant to cetuximab. Resistance was associated with an increase in heregulin expression and ErbB3 activation. However, concomitant cetuximab treatment with MM-121 blocked reactivation of ErbB3 and resulted in a sustained and durable response. Thus, these results suggest that targeting ErbB3 with MM-121 can be an effective therapeutic strategy for cancers with ligand-dependent activation of ErbB3. Cancer Res; 70(6); 2485–94
Chemoprevention of Intestinal Tumorigenesis in APCmin/+ Mice by Silibinin
Authors: Rajamanickam Subapriya , Velmurugan Balaiya , Kaur Manjinder , Singh Rana P. , Agarwal Rajesh
Published: March 2010

Chemoprevention is a practical and translational approach to reduce the risk of various cancers including colorectal cancer (CRC), which is a major cause of cancer-related deaths in the United States. Accordingly, here we assessed chemopreventive efficacy and associated mechanisms of long-term silibinin feeding on spontaneous intestinal tumorigenesis in the APCmin/+ mice model. Six-week-old APCmin/+ mice were p.o. fed with vehicle control (0.5% carboxymethyl cellulose and 0.025% Tween 20 in distilled water) or 750 mg silibinin/kg body weight in vehicle for 5 d/wk for 13 weeks and then sacrificed. Silibinin feeding strongly prevented intestinal tumorigenesis in terms of polyp formation in proximal, middle, and distal portions of small intestine by 27% (P < 0.001), 34% (P < 0.001), and 49% (P < 0.001), respectively. In colon, we observed 55% (P < 0.01) reduction in number of polyps by silibinin treatment. In size distribution analysis, silibinin showed significant decrease in large-size polyps (>3 mm) by 66% (P < 0.01) and 88% (P < 0.001) in middle and distal portions of small intestine, respectively. More importantly, silibinin caused a complete suppression in >3 mm sized polyps and 92% reduction in >2 to 3 mm sized polyps in colon. Molecular analyses of polyps suggested that silibinin exerts its chemopreventive efficacy by inhibiting cell proliferation, inflammation, and angiogenesis; inducing apoptosis; decreasing β-catenin levels and transcriptional activity; and modulating the expression profile of cytokines. These results show for the first time the efficacy and associated mechanisms of long-term p.o. silibinin feeding against spontaneous intestinal tumorigenesis in the APCmin/+ mice model, suggesting its chemopreventive potential against intestinal cancers including CRC. Cancer Res; 70(6); 2368–78
Identification of Hypermethylated Genes Associated with Cisplatin Resistance in Human Cancers
Authors: Chang Xiaofei , Monitto Constance L. , Demokan Semra , Kim Myoung Sook , Chang Steven S. , Zhong Xiaoli , Califano Joseph A. , Sidransky David
Published: March 2010

Cisplatin is among the most widely used cytotoxic anticancer agents in solid tumors; however, the development of secondary resistance remains a major obstacle to clinical efficacy. Treatment-related DNA hypermethylation may play a role in creating drug-resistant phenotypes by inactivating genes that are required for cytotoxicity. We applied a pharmacologic unmasking approach to detect hypermethylated genes whose inactivation contributes to cisplatin resistance. Using three pairs of isogeneic, cisplatin-sensitive, and cisplatin-resistant cell lines derived from two parental cell lines (KB-3-1 and SCC25), we identified several hundred genes that were downregulated in each resistant cell line and reactivated by the DNA methyltransferase inhibitor 5-aza-2′-deoxycytidine. Among them, 30 genes were common to two or more cell lines and/or reported to be downregulated in previous studies. Bisulfite sequencing confirmed that 14 genes were hypermethylated in resistant cell lines but not in the sensitive parental cell lines. Six of 14 genes (SAT, C8orf4, LAMB3, TUBB, G0S2, and MCAM) were cisplatin inducible in sensitive but not in resistant cell lines. Small interfering RNA knockdown of two genes, SAT and S100P, increased cell viability with cisplatin treatment in sensitive parental cell lines. S100P knockdown significantly decreased the S-phase fraction of parental sensitive cell lines and slowed cell proliferation, which was associated with decreased sensitivity to cisplatin. Based on these findings, we conclude that DNA methylation is a frequent event in cells that are chronically exposed to cisplatin and that methylation-induced gene silencing may play a role in the development of resistance to cytotoxic chemotherapeutic agents. Cancer Res; 70(7); 2870–9
A Genome-Wide Screen for Microdeletions Reveals Disruption of Polarity Complex Genes in Diverse Human Cancers
Authors: Rothenberg S. Michael , Mohapatra Gayatry , Rivera Miguel N. , Winokur Daniel , Greninger Patricia , Nitta Mai , Sadow Peter M. , Sooriyakumar Gaya , Brannigan Brian W. , Ulman Matthew J. , Perera Rushika M. , Wang Rui , Tam Angela , Ma Xiao-Jun , Erlander Mark , Sgroi Dennis C. , Rocco James W. , Lingen Mark W. , Cohen Ezra E.W. , Louis David N. , Settleman Jeffrey , Haber Daniel A.
Published: March 2010

In a genome-wide screen of 684 cancer cell lines, we identified homozygous intragenic microdeletions involving genes encoding components of the apical-basal cell polarity complexes. Among these, PARD3 is disrupted in cell lines and primary tumors from squamous carcinomas and glioblastomas. Reconstituting PARD3 expression in both cell types restores tight junctions and retards contact-dependent proliferation. Searching specifically for small intragenic microdeletions using high-resolution genomic arrays may be complementary to other genomic deletion screens and resequencing efforts in identifying new tumor suppressor genes. Cancer Res; 70(6); 2158–64
Exon Array Analyses across the NCI-60 Reveal Potential Regulation of TOP1 by Transcription Pausing at Guanosine Quartets in the First Intron
Authors: Reinhold William C. , Mergny Jean-Louis , Liu Hongfang , Ryan Michael , Pfister Thomas D. , Kinders Robert , Parchment Ralph , Doroshow James , Weinstein John N. , Pommier Yves
Published: March 2010

Because topoisomerase 1 (TOP1) is critical for the relaxation of DNA supercoils and because it is the target for the anticancer activity of camptothecins, we assessed TOP1 transcript levels in the 60 cell line panel (the NCI-60) of the National Cancer Institute's anticancer drug screen. TOP1 expression levels varied over a 5.7-fold range across the NCI-60. HCT116 colon and MCF-7 breast cancer cells were the highest expressers; SK-MEL-28 melanoma and HS578T breast carcinoma cells were the lowest. TOP1 mRNA expression was highly correlated with Top1 protein levels, indicating that TOP1 transcripts could be conveniently used to monitor Top1 protein levels and activity in tissues. Assessment of the TOP1 locus by array comparative genomic hybridization across the NCI-60 showed copy numbers ranging from 1.71 to 4.13 and a statistically significant correlation with TOP1 transcript levels (P < 0.01). Further analyses of TOP1 expression on an exon-specific basis revealed that exon 1 expression was generally higher and less variable than expression of the other exons, suggesting some form of transcriptional pausing regulation between exons 1 and 2. Accordingly, we found the presence of multiple evolutionarily conserved potential G-quadruplex–forming sequences in the first TOP1 intron. Physicochemical tests for actual quadruplex formation by several of those sequences yielded quadruplex formation for two of them and duplex formation for one. The observations reported here suggest the hypothesis that there is a conserved negative transcription regulator within intron 1 of the TOP1 gene associated with a quadruplex-prone region. Cancer Res; 70(6); 2191–203
Luteolin Inhibits Protein Kinase Cϵ and c-Src Activities and UVB-Induced Skin Cancer
Authors: Byun Sanguine , Lee Ki Won , Jung Sung Keun , Lee Eun Jung , Hwang Mun Kyung , Lim Sung Hwan , Bode Ann M. , Lee Hyong Joo , Dong Zigang
Published: March 2010

Luteolin, a flavonoid present in various vegetables including onion and broccoli, has been reported to possess anticarcinogenic effects. However, its chemopreventive effect on UV-induced skin cancer and its mechanism are not fully understood. Herein, we examined the chemopreventive effect and associated mechanisms of luteolin in the JB6 P+ cell line and the SKH-1 hairless mouse model. Luteolin suppressed UVB-induced cyclooxygenase-2 expression and activator protein-1 and nuclear factor-κB activity in JB6 P+ cells. Immunoblot and kinase assay data showed that luteolin attenuated protein kinase Cϵ (PKCϵ) and Src kinase activities and subsequently inhibited UVB-induced phosphorylation of mitogen-activated protein kinases and the Akt signaling pathway. In addition, pull-down assays revealed that luteolin binds directly to PKCϵ and Src in an ATP-competitive manner. Importantly, luteolin suppressed tumor incidence, multiplicity, and overall size in SKH-1 hairless mice. Analysis of the skin by immunohistochemistry and immunoblotting showed that luteolin-treated groups had a substantial reduction in the levels of cyclooxygenase-2, tumor necrosis factor-α, and proliferating cell nuclear antigen compared with groups treated with only UVB. Further analysis using skin lysates showed that luteolin inhibited PKCϵ and Src kinase activity. Together, these data suggest that luteolin exerts potent chemopreventive activity against UVB-induced skin cancer mainly by targeting PKCϵ and Src. Cancer Res; 70(6); 2415–23
Loss of DNA Polymerase ζ Enhances Spontaneous Tumorigenesis
Authors: Wittschieben John P. , Patil Vaishali , Glushets Veronika , Robinson Lisa J. , Kusewitt Donna F. , Wood Richard D.
Published: March 2010

Mammalian genomes encode at least 15 distinct DNA polymerases, functioning as specialists in DNA replication, DNA repair, recombination, or bypass of DNA damage. Although the DNA polymerase ζ (polζ) catalytic subunit REV3L is important in defense against genotoxins, little is known of its biological function. This is because REV3L is essential during embryogenesis, unlike other translesion DNA polymerases. Outstanding questions include whether any adult cells are viable in the absence of polζ and whether polζ status influences tumorigenesis. REV3L-deficient cells have properties that could influence the development of neoplasia in opposing ways: markedly reduced damage-induced point mutagenesis and extensive chromosome instability. To answer these questions, Rev3L was conditionally deleted from tissues of adult mice using MMTV-Cre. Loss of REV3L was tolerated in epithelial tissues but not in the hematopoietic lineage. Thymic lymphomas in Tp53−/− Rev3L conditional mice occurred with decreased latency and higher incidence. The lymphomas were populated predominantly by Rev3L-null T cells, showing that loss of Rev3L can promote tumorigenesis. Remarkably, the tumors were frequently oligoclonal, consistent with accelerated genetic changes in the absence of Rev3L. Mammary tumors could also arise from Rev3L-deleted cells in both Tp53+/+ and Tp53+/− backgrounds. Mammary tumors in Tp53+/− mice deleting Rev3L formed months earlier than mammary tumors in Tp53+/− control mice. Prominent preneoplastic changes in glandular tissue adjacent to these tumors occurred only in mice deleting Rev3L and were associated with increased tumor multiplicity. Polζ is the only specialized DNA polymerase yet identified that inhibits spontaneous tumor development. Cancer Res; 70(7); 2770–8
Glycoprotein Nonmetastatic B Is an Independent Prognostic Indicator of Recurrence and a Novel Therapeutic Target in Breast Cancer
Authors: Rose April A.N. , Grosset Andrée-Anne , Dong Zhifeng , Russo Caterina , MacDonald Patricia A. , Bertos Nicholas R. , St-Pierre Yves , Simantov Ronit , Hallett Michael , Park Morag , Gaboury Louis , Siegel Peter M.
Published: March 2010

Purpose: Although the murine orthologue of glycoprotein nonmetastatic B (GPNMB), Osteoactivin, promotes breast cancer metastasis in an in vivo mouse model, its importance in human breast cancer is unknown. We have examined the significance of GPNMB expression as a prognostic indicator of recurrence and assessed its potential as a novel therapeutic target in breast cancer.

Experimental Design: The clinical significance of GPNMB expression in breast cancer was addressed by analyzing GPNMB levels in several published gene expression data sets and two independent tissue microarrays derived from human breast tumors. GPNMB-expressing human breast cancer cell lines were further used to validate a toxin-conjugated anti-GPNMB antibody as a novel therapeutic agent.

Results: GPNMB expression correlates with shorter recurrence times and reduced overall survival of breast cancer patients. Epithelial-specific GPNMB staining is an independent prognostic indicator for breast cancer recurrence. GPNMB is highly expressed in basal and triple-negative breast cancers and is associated with increased risk of recurrence within this subtype. GPNMB expression confers a more migratory and invasive phenotype on breast cancer cells and sensitizes them to killing by CDX-011 (glembatumumab vedotin), a GPNMB-targeted antibody-drug conjugate.

Conclusions: GPNMB expression is associated with the basal/triple-negative subtype and is a prognostic marker of poor outcome in patients with breast cancer. CDX-011 (glembatumumab vedotin) is a promising new targeted therapy for patients with metastatic triple-negative breast cancers, a patient population that currently lacks targeted-therapy options. Clin Cancer Res; 16(7); 2147–56. ©2010 AACR.
Metformin: A Therapeutic Opportunity in Breast Cancer
Authors: Gonzalez-Angulo Ana M. , Meric-Bernstam Funda
Published: March 2010

Two important, related pathways are involved in cancer growth: the insulin/insulin-like growth factor-1 (IGF1) signaling pathway, which is activated when nutrients are available, and the adenosine mono-phosphate-activated protein kinase (AMPK) pathway, activated when cells are starved for carbohydrates. Metformin inhibits transcription of key gluconeogenesis genes in the liver, increases glucose uptake in skeletal muscle, and decreases circulating insulin levels. Metformin reduces levels of circulating glucose, increases insulin sensitivity, and reduces insulin resistance-associated hyperinsulinemia. At the level of cell signaling, metformin activates AMPK. There are extensive preclinical data showing the anticancer effects of metformin in all breast cancer subtypes as well as in cytotoxic therapy-resistant models. These data, and the epidemiological and retrospective data supporting the antineoplastic effects of metformin, provide the rationale to study the role of metformin for breast cancer therapy in a variety of clinical settings. Clin Cancer Res; 16(6); 1695–700
Highly Phosphorylated FOXO3A Is an Adverse Prognostic Factor in Acute Myeloid Leukemia
Authors: Kornblau Steven M. , Singh Neera , Qiu YiHua , Chen Wenjing , Zhang Nianxiang , Coombes Kevin R.
Published: March 2010

Purpose: The Forkhead transcription factors (FOXO) are tumor suppressor genes regulating differentiation, metabolism, and apoptosis that functionally interact with signal transduction pathways shown to be deregulated and prognostic in acute myelogenous leukemia (AML). This study evaluated the level of expression and the prognostic relevance of total and phosphorylated FOXO3A protein in AML.

Experimental Design: We used reverse-phase protein array methods to measure the level of total and phosphoprotein expression of FOXO3A, in leukemia-enriched protein samples from 511 newly diagnosed AML patients.

Results: The expression range was similar to normal CD34+ cells and similar in blood and marrow. Levels of total FOXO3A were higher at relapse compared with diagnosis. Levels of pFOXO3A or the ratio of phospho to total (PT) were not associated with karyotpe but were higher in patients with FLT3 mutations. Higher levels of pFOXO3A or PT-FOXO3A were associated with increased proliferation evidenced by strong correlation with higher WBC, percent marrow, and blood blasts and by correlation with higher levels of Cyclins B1, D1 and D3, pGSK3, pMTOR, and pStat5. Patients with High levels of pFOXO3A or PT-FOXO3A had higher rates of primary resistance and shorter remission durations, which combine to cause an inferior survival experience (P = 0.0002). This effect was independent of cytogenetics. PT-FOXO3A was a statistically significant independent predictor in multivariate analysis.

Conclusions: High levels of phosphorylation of FOXO3A is a therapeutically targetable, independent adverse prognostic factor in AML. Clin Cancer Res; 16(6); 1865–74
A High Proportion of DNA Variants ofBRCA1andBRCA2Is Associated with Aberrant Splicing in Breast/Ovarian Cancer Patients
Authors: Sanz David J. , Acedo Alberto , Infante Mar , Durán Mercedes , Pérez-Cabornero Lucía , Esteban-Cardeñosa Eva , Lastra Enrique , Pagani Franco , Miner Cristina , Velasco Eladio A.
Published: March 2010

Purpose: Most BRCA1/2 mutations are of unknown clinical relevance. An increasing amount of evidence indicates that there can be deleterious effects through the disruption of the splicing process. We have investigated the effect of aberrant splicing of BRCA1/2 on hereditary breast/ovarian cancer (HBOC).

Experimental Design: DNA variants were analyzed with splicing prediction programs to select putative splicing mutations. Splicing assays of 57 genetic variants were done by lymphocyte reverse transcription-PCR and/or hybrid minigenes in HeLa and nontumor breast epithelial cells.

Results: Twenty-four BRCA1/2 variants of Spanish HBOC patients were bioinformatically preselected. Functional assays showed that 12 variants induced anomalous splicing patterns, 6 of which accounted for 58.5% of BRCA1 families. To further evaluate the defective splicing of BRCA1/2, we analyzed 31 Breast Cancer Information Core Database (BIC) and two artificial variants that were generated by mutagenesis. Sixteen variants induced different degrees of aberrant splicing. Altogether, anomalous splicing was caused by 28 BRCA1/2 variants of all types, indicating that any DNA change can disrupt pre-mRNA processing. We show that a wide range of regulatory elements can be involved, including the canonical and cryptic splice sites, the polypyrimidine tract, and splicing enhancers/silencers. Twenty mutations were predicted to truncate the BRCA proteins and/or to delete essential domains, thus supporting a role in HBOC.

Conclusions: An important fraction of DNA variants of BRCA1/2 presents splicing aberrations that may represent a relevant disease-causing mechanism in HBOC. The identification of splicing disruptions by functional assays is a valuable tool to discriminate between benign polymorphisms and pathogenic mutations. Clin Cancer Res; 16(6); 1957–67
Obesity Is an Independent Prognostic Variable in Colon Cancer Survivors
Authors: Sinicrope Frank A. , Foster Nathan R. , Sargent Daniel J. , O'Connell Michael J. , Rankin Cathryn
Published: March 2010

Purpose: Obesity is associated with an increased risk of colon cancer. However, the influence of body mass index (BMI) on the prognosis of colon cancer survivors and its relationship to gender remains unknown.

Experimental Design: BMI (kg/m2) was categorized in patients with tumor-node-metastasis stage II and III colon carcinomas (n = 4,381) enrolled in seven randomized trials of 5-fluorouracil–based adjuvant chemotherapy. Cox proportional hazards models were used to determine the association of BMI with disease-free survival (DFS) and overall survival (OS).

Results: Among colon cancer patients, 868 (20%) were obese (BMI, ≥30 kg/m2), of which 606 were class 1 (BMI, 30-34 kg/m2) and 262 were class 2,3 (BMI, ≥35 kg/m2). Obese versus normal-weight patients were more likely to be younger, have distal tumors, show intact DNA mismatch repair, and have more lymph node metastases (P < 0.017). In a multivariate analysis, BMI was significantly associated with both DFS (P = 0.030) and OS (P = 0.0017). Men with class 2,3 obesity showed reduced OS compared with normal-weight men [hazard ratio, 1.35; 95% confidence interval, 1.02-1.79; P = 0.039]. Women with class I obesity had reduced OS [hazard ratio, 1.24; 95% confidence interval, 1.01-1.53; P = 0.045] compared with normal-weight women. Overweight status was associated with improved OS in men (P = 0.006), and underweight women had significantly worse OS (P = 0.019). BMI was not predictive of therapeutic benefit.

Conclusions: Obesity is an independent prognostic variable in colon cancer survivors and shows gender-related differences. These data suggest that obesity-related biological factors can influence clinical outcome. Clin Cancer Res; 16(6); 1884–93
Homozygous Deletion Mapping in Myeloma Samples Identifies Genes and an Expression Signature Relevant to Pathogenesis and Outcome
Authors: Dickens Nicholas J. , Walker Brian A. , Leone Paola E. , Johnson David C. , Brito José L. , Zeisig Athanasia , Jenner Matthew W. , Boyd Kevin D. , Gonzalez David , Gregory Walter M. , Ross Fiona M. , Davies Faith E. , Morgan Gareth J.
Published: March 2010

Purpose: Myeloma is a clonal malignancy of plasma cells. Poor-prognosis risk is currently identified by clinical and cytogenetic features. However, these indicators do not capture all prognostic information. Gene expression analysis can be used to identify poor-prognosis patients and this can be improved by combination with information about DNA-level changes.

Experimental Design: Using single nucleotide polymorphism–based gene mapping in combination with global gene expression analysis, we have identified homozygous deletions in genes and networks that are relevant to myeloma pathogenesis and outcome.

Results: We identified 170 genes with homozygous deletions and corresponding loss of expression. Deletion within the “cell death” network was overrepresented and cases with these deletions had impaired overall survival. From further analysis of these events, we have generated an expression-based signature associated with shorter survival in 258 patients and confirmed this signature in data from two independent groups totaling 800 patients. We defined a gene expression signature of 97 cell death genes that reflects prognosis and confirmed this in two independent data sets.

Conclusions: We developed a simple 6-gene expression signature from the 97-gene signature that can be used to identify poor-prognosis myeloma in the clinical environment. This signature could form the basis of future trials aimed at improving the outcome of poor-prognosis myeloma. Clin Cancer Res; 16(6); 1856–64
Therapeutic Potential of Janus-activated Kinase-2 Inhibitors for the Management of Myelofibrosis
Authors: Verstovsek Srdan
Published: March 2010

Myelofibrosis (either primary or postpolycythemia vera/essential thrombocythemia) is a chronic and debilitating myeloproliferative neoplasm for which there is no well-accepted standard of care. Clinical manifestations of this disease (e.g., cytopenias, splenomegaly, bone marrow fibrosis) and constitutional symptoms (e.g., hypercatabolic state, fatigue, night sweats, fever) create significant treatment challenges. For example, progressive splenomegaly increases the risk for more serious clinical sequelae (e.g., portal hypertension, splenic infarction). Myelofibrosis arises from hematopoietic stem cells or early progenitor cells. However, the molecular mechanisms underlying its pathogenesis and clinical presentation are poorly understood, delaying the development of effective and targeted treatments. Recent studies have implicated mutations that directly or indirectly lead to the deregulated activation of Janus-activated kinase 2 (JAK2). Appreciation for the activation of JAK2 and the importance of increased levels of circulating proinflammatory cytokines in the pathogenesis and clinical manifestations of myelofibrosis has led to novel therapeutic agents targeting JAKs. This review will briefly discuss the origins of the JAK2 hypothesis, the clinical relevance of JAK2 mutations in myelofibrosis, and recent clinical progress in targeting JAKs as a therapeutic intervention for patients with this chronic and debilitating disease. Clin Cancer Res; 16(7); 1988–96. ©2010 AACR.