bluuebunny/crossref_metadata_2025_split huggingface dataset:
Role of Peroxisome Proliferator-Activated Receptor-γ and Its Coactivator DRIP205 in Cellular Responses to CDDO (RTA-401) in Acute Myelogenous Leukemia
Authors: Tsao Twee , Kornblau Steven , Safe Stephen , Watt Julie C. , Ruvolo Vivian , Chen Wenjing , Qiu Yihua , Coombes Kevin R. , Ju Zhenlin , Abdelrahim Maen , Schober Wendy , Ling Xiaoyang , Kardassis Dimitris , Meyer Colin , Schimmer Aaron , Kantarjian Hagop , Andreeff Michael , Konopleva Marina 
Published: May 2010

Abstract
Peroxisome proliferator-activated receptor-γ (PPARγ) is a member of the nuclear receptor (NR) family of transcription factors with important regulatory roles in cellular growth, differentiation, and apoptosis. Using proteomic analysis, we showed expression of PPARγ protein in a series of 260 newly diagnosed primary acute myelogenous leukemia (AML) samples. Forced expression of PPARγ enhanced the sensitivity of myeloid leukemic cells to apoptosis induced by PPARγ agonists 2-cyano-3,12-dioxooleana-1,9-dien-28-oic acid (CDDO) and 15-deoxy-12,14-15DPGJ2, through preferential cleavage of caspase-8. No effects on cell cycle distribution or differentiation were noted, despite prominent induction of p21 in PPARγ-transfected cells. In turn, antagonizing PPARγ function by small interfering RNA or pharmacologic PPARγ inhibitor significantly diminished apoptosis induction by CDDO. Overexpression of coactivator protein DRIP205 resulted in enhanced differentiation induction by CDDO in AML cells through PPARγ activation. Studies with DRIP205 deletion constructs showed that the NR boxes of DRIP205 are not required for this coactivation. In a phase I clinical trial of CDDO (RTA-401) in leukemia, CDDO induced an increase in PPARγ mRNA expression in six of nine patient samples; of those, induction of differentiation was documented in four patients and that of p21 in three patients, all expressing DRIP205 protein. In summary, these findings suggest that cellular levels of PPARγ regulate induction of apoptosis via caspase-8 activation, whereas the coactivator DRIP205 is a determinant of induction of differentiation, in response to PPARγ agonists in leukemic cells. Cancer Res; 70(12); 4949–60. ©2010 AACR.
Arrest Defective 1 Autoacetylation Is a Critical Step in Its Ability to Stimulate Cancer Cell Proliferation
Authors: Seo Ji Hae , Cha Jong-Ho , Park Ji-Hyeon , Jeong Chul-Ho , Park Zee-Yong , Lee Hye-Suk , Oh Seung Hyun , Kang Ju-Hee , Suh Se Won , Kim Kyoung Hoon , Ha Jun Yong , Han Sang Hee , Kim Se-Hee , Lee Ji-Won , Park Jeong Ae , Jeong Joo-Won , Lee Kong-Joo , Oh Goo Taeg , Lee Mi-Ni , Kwon Sung Won , Lee Seung-Ki , Chun Kwang-Hoon , Lee Su-Jae , Kim Kyu-Won 
Published: May 2010

AbstractThe N-acetyltransferase arrest defective 1 (ARD1) is an important regulator of cell growth and differentiation that has emerged recently as a critical molecule in cancer progression. However, the regulation of the enzymatic and biological activities of human ARD1 (hARD1) in cancer is presently poorly understood. Here, we report that hARD1 undergoes autoacetylation and that this modification is essential for its functional activation. Using liquid chromatography-tandem mass spectrometry and site-directed mutational analyses, we identified K136 residue as an autoacetylation target site. K136R mutation abolished the ability of hARD1 to promote cancer cell growth in vitro and tumor xenograft growth in vivo. Mechanistic investigations revealed that hARD1 autoacetylation stimulated cyclin D1 expression through activation of the transcription factors β-catenin and activator protein-1. Our results show that hARD1 autoacetylation is critical for its activation and its ability to stimulate cancer cell proliferation and tumorigenesis. Cancer Res; 70(11); 4422–32. ©2010 AACR.
Novel Dyskerin-Mediated Mechanism of p53 Inactivation through Defective mRNA Translation
Authors: Montanaro Lorenzo , Calienni Maria , Bertoni Sara , Rocchi Laura , Sansone Pasquale , Storci Gianluca , Santini Donatella , Ceccarelli Claudio , Taffurelli Mario , Carnicelli Domenica , Brigotti Maurizio , Bonafè Massimiliano , Treré Davide , Derenzini Massimo 
Published: May 2010

Abstract
In up to 60% of human cancers, p53 gene mutations are responsible for direct inactivation of the tumor suppressor function of p53. Alternative mechanisms of p53 inactivation described thus far mainly affect its posttranslational regulation. In X-linked dyskeratosis congenita, a multisystemic syndrome characterized by increased cancer susceptibility, mutations of the DKC1 gene encoding dyskerin cause a selective defect in the translation of a subgroup of internal ribosome entry site (IRES)–containing cellular mRNAs. In this study, we show that impairment of dyskerin function can cause p53 inactivation due to a defect in p53 mRNA translation. siRNA-mediated reduction of dyskerin levels caused a decrease of p53 mRNA translation, protein levels, and functional activity, both in human breast cancer cells and in primary mammary epithelial progenitor cells. These effects seemed to be independent of the known role of dyskerin in telomerase function, and they were associated with a specific impairment of translation initiation mediated by IRES elements present in p53 mRNA. In a series of human primary breast cancers retaining wild-type p53, we found that low levels of dyskerin expression were associated with reduced expression of p53-positive target genes. Our findings suggest that a dyskerin-mediated mechanism of p53 inactivation may occur in a subset of human tumors. Cancer Res; 70(11); 4767–77. ©2010 AACR.
Oncogenic Ras Promotes Reovirus Spread by Suppressing IFN-β Production through Negative Regulation of RIG-I Signaling
Authors: Shmulevitz Maya , Pan Lu-Zhe , Garant Katy , Pan Da , Lee Patrick W.K. 
Published: May 2010

Abstract
Reovirus is the first naturally occurring human virus reported to exploit activated Ras signaling in the host cell for infection, and is currently undergoing clinical trials as a cancer therapeutic. Recent evidence suggests that Ras transformation promotes three reoviral replication steps during the first round of infection: uncoating of the incoming virion, generation of progeny viruses with enhanced infectivity, and virus release through enhanced apoptosis. Whether oncogenic Ras also enhances reovirus spread in subsequent rounds of infection through other mechanisms has not been examined. Here, we show that compared with nontransformed cells, Ras-transformed cells are severely compromised not only in their response to IFN-β, but also in the induction of IFN-β mRNA following reovirus infection. Defects in both IFN-β production and response allow for efficient virus spread in Ras-transformed cells. We show that the MEK/ERK pathway downstream of Ras is responsible for inhibiting IFN-β expression by blocking signaling from the retinoic acid–inducible gene I (RIG-I) which recognizes viral RNAs. Overexpression of wild-type RIG-I restores INF-β expression in reovirus-infected Ras-transformed cells. In vitro–synthesized viral mRNAs also invoke robust RIG-I–mediated IFN-β production in transfected nontransformed cells, but not in Ras-transformed cells. Collectively, our data suggest that oncogenic Ras promotes virus spread by suppressing viral RNA–induced IFN-β production through negative regulation of RIG-I signaling. Cancer Res; 70(12); 4912–21. ©2010 AACR.
14-3-3 Binding Sites in the Snail Protein Are Essential for Snail-Mediated Transcriptional Repression and Epithelial-Mesenchymal Differentiation
Authors: Hou Zhaoyuan , Peng Hongzhuang , White David E. , Wang Pu , Lieberman Paul M. , Halazonetis Thanos , Rauscher Frank J. 
Published: May 2010

Abstract
The Snail transcription factor is a repressor and a master regulator of epithelial-mesenchymal transition (EMT) events in normal embryonic development and during tumor metastases. Snail directly regulates genes affecting cell adhesion, motility, and polarity. Invasive tumor cells express high levels of Snail, which is a marker for aggressive disease and poor prognosis. Transcriptional repression and EMT induction by Snail requires binding to its obligate corepressor, the LIM protein Ajuba. It is unclear how this complex is assembled and maintained on Snail target genes. Here we define functional 14-3-3 binding motifs in Snail and Ajuba, which selectively bind 14-3-3 protein isoforms. In Snail, an NH2-terminal motif in the repression domain cooperates with a COOH-terminal, high-affinity motif for binding to 14-3-3 proteins. Coordinate mutation of both motifs abolishes 14-3-3 binding and inhibits Snail-mediated gene repression and EMT differentiation. Snail, 14-3-3 proteins, and Ajuba form a ternary complex that is readily detected through chromatin immunoprecipitation at the endogenous E-cadherin promoter. Collectively, these data show that 14-3-3 proteins are new components of the Snail transcriptional repression machinery and mediate its important biological functions. Cancer Res; 70(11); 4385–93. ©2010 AACR.
Reversal of Chemotherapy-Induced Leukopenia Using Granulocyte Macrophage Colony-Stimulating Factor Promotes Bone Metastasis That Can Be Blocked with Osteoclast Inhibitors
Authors: Dai Jinlu , Lu Yi , Yu Chunyan , Keller Jill M. , Mizokami Atsushi , Zhang Jian , Keller Evan T. 
Published: May 2010

Abstract
Hematopoietic growth factors are used to reverse chemotherapy-induced leukopenia. However, some factors such as granulocyte macrophage colony-stimulating factor (GM-CSF) induce osteoclast-mediated bone resorption that can promote cancer growth in the bone. Accordingly, we evaluated the ability of GM-CSF to promote bone metastases of breast cancer or prostate cancer in a mouse model of chemotherapy-induced leukopenia. In this model, GM-CSF reversed cyclophosphamide-induced leukopenia but also promoted breast cancer and prostate cancer growth in the bone but not in soft tissue sites. Bone growth was associated with the induction of osteoclastogenesis, yet in the absence of tumor GM-CSF, it did not affect osteoclastogenesis. Two osteoclast inhibitors, the bisphosphonate zoledronic acid and the RANKL inhibitor osteoprotegerin, each blocked GM-CSF–induced tumor growth in the bone but did not reverse the ability of GM-CSF to reverse chemotherapy-induced leukopenia. Our findings indicate that it is possible to dissociate the bone-resorptive effects of GM-CSF, to reduce metastatic risk, from the benefits of this growth factor in reversing leukopenia caused by treatment with chemotherapy. Cancer Res; 70(12); 5014–23. ©2010 AACR.
L1 Cell Adhesion Molecule Is a Novel Therapeutic Target in Intrahepatic Cholangiocarcinoma
Authors: Min Jeong-Ki , Kim Jin-Man , Li Shengjin , Lee Jung Whoi , Yoon Hyunho , Ryu Chun Jeih , Jeon Soung Hoo , Lee Jae-Hyek , Kim Jin Young , Yoon Hee Kwan , Lee Young Kwan , Kim Bong-Hui , Son Yeon Sung , Choi Hong Seo , Lim Nam-Kyu , Kim Dae-Ghon , Hong Hyo Jeong 
Published: May 2010

AbstractPurpose: Intrahepatic cholangiocarcinoma (ICC), a highly malignant hepatobiliary cancer, has a poor prognosis and is refractory to conventional therapies. The aim of this study is to discover a novel molecular target for the treatment of ICC.Experimental Design: To discover novel cancer-associated membrane antigens expressed in ICC cells, we generated monoclonal antibodies (mAb) by immunizing mice with intact ICC cell lines and screened for those that bind to the plasma membrane of ICC cells but not to normal cells. The mAb A10-A3 was selected and its target antigen was identified as the L1 cell adhesion molecule. Expression of L1 in ICC was evaluated by immunohistochemical analysis of tumor samples from 42 ICC patients. The functional significance of L1 expression in the tumor progression of ICC was investigated by L1 suppression, L1 overexpression, and antibody treatment.Results: L1 was not expressed in normal hepatocytes and intrahepatic bile duct epithelium but highly expressed in 40.5% of ICC patients, remarkably at the invasive front of the tumors. Suppression of L1 with short hairpin RNA significantly decreased proliferation, migration, and invasion of ICC cells in vitro. Consistently, L1 overexpression in ICC cells enhanced proliferation, migration, invasion, and apoptosis resistance. In addition, L1 short hairpin RNA or anti-L1 mAb significantly reduced the tumor growth in nude mice bearing ICC xenograft.Conclusions: We identified that L1 is expressed in ICC. L1 plays an important role in the tumor progression of ICC by enhancing cell proliferation, migration, invasion, and survival. L1 may represent a novel therapeutic target for ICC. Clin Cancer Res; 16(14); 3571–80. ©2010 AACR.
A Pharmacodynamic Study of Rapamycin in Men with Intermediate- to High-Risk Localized Prostate Cancer
Authors: Armstrong Andrew J. , Netto George J. , Rudek Michelle A. , Halabi Susan , Wood David P. , Creel Patricia A. , Mundy Kelly , Davis S. Lindsay , Wang Ting , Albadine Roula , Schultz Luciana , Partin Alan W. , Jimeno Antonio , Fedor Helen , Febbo Phillip G. , George Daniel J. , Gurganus Robin , De Marzo Angelo M. , Carducci Michael A. 
Published: May 2010

Abstract
Purpose: Given discrepancies between preclinical and clinical observations of mammalian target of rapamycin (mTOR) inhibition in prostate cancer, we sought to determine the pharmacodynamic effects of the mTOR/TORC1 inhibitor rapamycin in men with intermediate- to high-risk prostate cancer undergoing radical prostatectomy.
Experimental Design: Rapamycin was given at 3 or 6 mg orally for 14 days before radical prostatectomy in men with multifocal Gleason sum ≥7 prostate cancer; 10 untreated control subjects were included. The primary outcome was inhibition of phosphorylation of ribosomal S6 in posttreatment radical prostatectomy versus pretreatment biopsy tumor tissue, evaluated using a Simon two-stage design for pharmacodynamic efficacy.
Results: Thirty-two subjects were accrued: 20 at 3 mg, 2 at 6 mg, and 10 controls. No dose-limiting toxicities were observed at 3 mg; however, two of two men enrolled at 6 mg experienced dose-limiting toxicities including thrombocytopenia and fever with grade 3 stomatitis. Adverse events observed at 3 mg included stomatitis, rash, ileus, and neutropenia. Pharmacodynamic studies showed tumor S6 phosphorylation inhibition in 50% of 10 evaluable rapamycin-treated men with sufficient paired tissue [median 58% inhibition (P = 0.049) versus 2% inhibition in controls (P = 0.75)] with no significant effect on AKT activity. We observed no change in Ki-67 or caspase-3 cleavage but noted a reduction in cytoplasmic p27 staining with increased nuclear localization with rapamycin treatment. Prostate tissue rapamycin concentrations were 3- to 4-fold higher than blood.
Conclusions: At 3 mg daily, rapamycin successfully and safely inhibited prostate cancer S6 phosphorylation and achieved relatively high prostate tissue concentrations. No effect on AKT phosphorylation, tumor proliferation, or apoptosis was observed. Clin Cancer Res; 16(11); 3057–66. ©2010 AACR.
Angiogenin Regulation by Estradiol in Breast Tissue: Tamoxifen Inhibits Angiogenin Nuclear Translocation and Antiangiogenin Therapy Reduces Breast Cancer Growth In vivo
Authors: Nilsson Ulrika W. , Abrahamsson Annelie , Dabrosin Charlotta 
Published: May 2010

Abstract
Purpose: Angiogenin, a 14.2-kDa polypeptide member of the RNase A superfamily, has potent angiogenic effects. Nuclear accumulation of angiogenin is essential for its angiogenic activity. Increased angiogenin expression has been associated with the transition of normal breast tissue into invasive breast carcinoma. In this article, we investigated whether estradiol (E2) affected angiogenin in breast tissue.
Experimental Design: We used microdialysis for sampling of extracellular angiogenin in vivo. In vitro cultures of whole normal breast tissue, breast cancer cells, and endothelial cells were used.
Results: We show that extracellular angiogenin correlated significantly with E2 in normal human breast tissue in vivo and that exposure of normal breast tissue biopsies to E2 stimulated angiogenin secretion. In breast cancer patients, the in vivo angiogenin levels were significantly higher in tumors compared with the adjacent normal breast tissue. In estrogen receptor–positive breast cancer cells, E2 increased and tamoxifen decreased angiogenin secretion. Moreover, E2-induced angiogenin derived from cancer cells significantly increased endothelial cell proliferation. Tamoxifen reversed this increase as well as inhibited nuclear translocation of angiogenin. In vivo, in experimental breast cancer, tamoxifen decreased angiogenin levels and decreased angiogenesis. Additionally, treating tumor-bearing mice with an antiangiogenin antibody resulted in tumor stasis, suggesting a role for angiogenin in estrogen-dependent breast cancer growth.
Conclusion: Our results suggest previously unknown mechanisms by which estrogen and antiestrogen regulate angiogenesis in normal human breast tissue and breast cancer. This may be important for estrogen-driven breast cancer progression and a molecular target for therapeutic interventions. Clin Cancer Res; 16(14); 3659–69. ©2010 AACR.
AACR-FDA-NCI Cancer Biomarkers Collaborative Consensus Report: Advancing the Use of Biomarkers in Cancer Drug Development
Authors: Khleif Samir N. , Doroshow James H. , Hait William N. 
Published: May 2010

Abstract
Recent discoveries in cancer biology have greatly increased our understanding of cancer at the molecular and cellular level, but translating this knowledge into safe and effective therapies for cancer patients has proved to be challenging. There is a growing imperative to modernize the drug development process by incorporating new techniques that can predict the safety and effectiveness of new drugs faster, with more certainty, and at lower cost. Biomarkers are central to accelerating the identification and adoption of new therapies, but currently, many barriers impede their use in drug development and clinical practice. In 2007, the AACR-FDA-NCI Cancer Biomarkers Collaborative stepped into the national effort to bring together disparate stakeholders to clearly delineate these barriers, to develop recommendations for integrating biomarkers into the cancer drug development enterprise, and to set in motion the necessary action plans and collaborations to see the promise of biomarkers come to fruition, efficiently delivering quality cancer care to patients. Clin Cancer Res; 16(13); 3299–318. ©2010 AACR.
Induction of Clusterin by AKT—Role in Cytoprotection against Docetaxel in Prostate Tumor Cells
Authors: Zhong Bin , Sallman David A. , Gilvary Danielle L. , Pernazza Daniele , Sahakian Eva , Fritz Dillon , Cheng Jin Q. , Trougakos Ioannis , Wei Sheng , Djeu Julie Y. 
Published: May 2010

AbstractClusterin (CLU), in its cytoplasmic form, is abundant in many advanced cancers and has been established to be cytoprotective against chemotherapeutic agents including docetaxel. However, little is known of the mechanism of its induction. Here, we provide evidence that AKT plays a critical role in upregulating cytoplasmic/secretory sCLU, which is responsible for docetaxel resistance. Western blot analysis indicated that docetaxel-resistant sublines derived from DU145 and PC3 prostate tumor cell lines displayed a markedly increased phospho-AKT level closely accompanied by heightened sCLU expression when compared with parental cells. To examine if AKT has a role in sCLU expression, AKT blockade was done by treatment with a specific inhibitor, API-2, or dominant-negative AKT transduction before analysis of sCLU gene expression. Loss of AKT function resulted in loss of sCLU and was accompanied by chemosensitization to docetaxel and increased cell death via a caspase-3–dependent pathway. To confirm that AKT affected resistance to docetaxel through sCLU and not through other mediators, tumor cells were first transfected with full-length CLU for overexpression and then treated with the AKT inhibitor API-2. We found that once sCLU was overexpressed, API-2 could not chemosensitize the tumor cells to docetaxel. Thus, the chemoresistance to docetaxel is mediated by sCLU and it can be induced by AKT. Lastly, AKT was found to mediate sCLU induction via signal transducer and activator of transcription 1 activation, which we have earlier shown to drive sCLU gene expression. These results identify a previously unrecognized pathway linking AKT to cytoprotection by sCLU in tumor cells. Mol Cancer Ther; 9(6); 1831–41. ©2010 AACR.
Preclinical Evaluation of Differentially Targeting Dual Virotherapy for Human Solid Cancer
Authors: Sakai Ryo , Kagawa Shunsuke , Yamasaki Yasumoto , Kojima Toru , Uno Futoshi , Hashimoto Yuuri , Watanabe Yuichi , Urata Yasuo , Tanaka Noriaki , Fujiwara Toshiyoshi 
Published: May 2010

AbstractMultimodal approaches combining drugs that differentially function is the most popular regimen for treating human cancer. Understanding the molecular mechanisms underlying the synergistic, potentiative, and antagonistic effects of drug combinations could facilitate the discovery of novel efficacious combinations. We previously showed that telomerase-specific replication-competent adenovirus (Telomelysin, OBP-301), in which the human telomerase reverse transcriptase promoter controls the adenoviral E1 gene expression, induces a selective antitumor effect in human cancer cells. Here, using E1-deleted replication-deficient adenovirus expressing the p53 tumor suppressor gene (Advexin, Ad-p53) and OBP-301, we investigate how these adenoviruses that kill tumor cells with different mechanisms could work in combination on human cancer. We found that E1-deficient Ad-p53 could kill cancer cells more efficiently in the presence of OBP-301 than Ad-p53 alone or OBP-301 alone, because Ad-p53 could become replication-competent by being supplied adenoviral E1 from coinfected OBP-301 in trans. Ad-p53 plus OBP-301 induced high levels of p53 protein expression without p21 induction, resulting in apoptotic cell death documented by active caspase-3 expression with a cytometric bead array and an increased subdiploid apoptotic fraction of the cell cycle. For in vivo evaluation, nude mice xenografted with human lung tumors received intratumoral injection of OBP-301 and/or Ad-p53. Analysis of the growth of implanted tumors showed an enhanced antitumor effect in combination therapy. Our data show that Ad-p53 in combination with OBP-301 induces not only oncolytic but also apoptotic cancer cell death and enhances antitumor activity in vitro and in vivo, providing potential merits as a multimodal treatment for human cancer. Mol Cancer Ther; 9(6); 1884–93. ©2010 AACR.