bluuebunny/crossref_metadata_2025_split huggingface dataset:
Progressive Chromatin Repression and Promoter Methylation of CTNNA1 Associated with Advanced Myeloid Malignancies
Authors: Ye Ying , McDevitt Michael A. , Guo Mingzhou , Zhang Wei , Galm Oliver , Gore Steven D. , Karp Judith E. , Maciejewski Jaroslaw P. , Kowalski Jeanne , Tsai Hua-Ling , Gondek Lukasz P. , Tsai Hsing-Chen , Wang Xiaofei , Hooker Craig , Smith B. Douglas , Carraway Hetty E. , Herman James G. 
Published: October 2009

Abstract
Complete loss or deletion of the long arm of chromosome 5 is frequent in myelodysplastic syndrome (MDS) and acute myelogenous leukemia (AML). The putative gene(s) deleted and responsible for the pathogenesis of these poor prognosis hematologic disorders remain controversial. This study is a comprehensive analysis of previously implicated and novel genes for epigenetic inactivation in AML and MDS. In 146 AML cases, methylation of CTNNA1 was frequent, and more common in AML patients with 5q deletion (31%) than those without 5q deletion (14%), whereas no methylation of other 5q genes was observed. In 31 MDS cases, CTNNA1 methylation was only found in high-risk MDS (≥RAEB2), but not in low-risk MDS (&lt;RAEB2), indicating that CTNNA1 methylation might be important in the transformation of MDS to AML. CTNNA1 expression was lowest in AML/MDS patients with CTNNA1 methylation, although reduced expression was found in some patients without promoter methylation. Repressive chromatin marks (H3K27me3) at the promoter were identified in CTNNA1-repressed AML cell lines and primary leukemias, with the most repressive state correlating with DNA methylation. These results suggest progressive, acquired epigenetic inactivation at CTNNA1, including histone modifications and promoter CpG methylation, as a component of leukemia progression in patients with both 5q− and non-5q– myeloid malignancies. [Cancer Res 2009;69(21):8482–90]
Molecular Consequences of Genetic Variations in the Glutathione Peroxidase 1 Selenoenzyme
Authors: Zhuo Pin , Goldberg Marci , Herman Lauren , Lee Bao-Shiang , Wang Hengbing , Brown Rhonda L. , Foster Charles B. , Peters Ulrike , Diamond Alan M. 
Published: October 2009

Abstract
Accumulating data have implicated the selenium-containing cytosolic glutathione peroxidase, GPx-1, as a determinant of cancer risk and a mediator of the chemopreventive properties of selenium. Genetic variants of GPx-1 have been shown to be associated with cancer risk for several types of malignancies. To investigate the relationship between GPx-1 enzyme activity and genotype, we measured GPx-1 enzyme activity and protein levels in human lymphocytes as a function of the presence of two common variations: a leucine/proline polymorphism at codon 198 and a variable number of alanine-repeat codons. Differences in GPx activity among these cell lines, as well as in the response to the low-level supplementation of the media with selenium, indicated that factors other than just genotype are significant in determining activity. To restrict the study to genotypic effects, human MCF-7 cells were engineered to exclusively express allelic variants representing a combination of either a codon 198 leucine or proline and either 5 or 7 alanine-repeat codons following transfection of GPx-1 expression constructs. Transfectants were selected and analyzed for GPx-1 enzyme activity and protein levels. GPx-1 with 5 alanines and a leucine at codon 198 showed a significantly higher induction when cells were incubated with selenium and showed a distinct pattern of thermal denaturation as compared with GPx-1 encoded by the other examined alleles. The collective data obtained using both lymphocytes and MCF-7 indicate that both intrinsic and extrinsic factors cooperate to ultimately determine the levels of this enzyme available to protect cells against DNA damage and mutagenesis. [Cancer Res 2009;69(20):8183–90]
Protein Kinase CK2 Regulates Cytoskeletal Reorganization during Ionizing Radiation–Induced Senescence of Human Mesenchymal Stem Cells
Authors: Wang Daojing , Jang Deok-Jin 
Published: October 2009

Abstract
Human mesenchymal stem cells (hMSC) are critical for tissue regeneration. How hMSC respond to genotoxic stresses and potentially contribute to aging and cancer remain underexplored. We showed that ionizing radiation induced cellular senescence of hMSC over a period of 10 days, showing a critical transition between days 3 and 6. This was confirmed by senescence-associated β-galactosidase staining, protein expression profiles of key cell cycle regulators (retinoblastoma protein, p53, p21waf1/Cip1, and p16INK4A), and senescence-associated secretory phenotypes (interleukin-8, interleukin-12, GRO, and MDC). We observed dramatic cytoskeletal reorganization of hMSC through reduction of myosin-10, redistribution of myosin-9, and secretion of profilin-1. Using a SILAC-based phosphoproteomics method, we detected significant reduction of myosin-9 phosphorylation at Ser1943, coinciding with its redistribution. Importantly, through treatment with cell-permeable inhibitors (4,5,6,7-tetrabromo-1H-benzotriazole and 2-dimethylamino-4,5,6,7-tetrabromo-1H-benzimidazole) and gene knockdown using RNA interference, we identified CK2, a kinase responsible for myosin-9 phosphorylation at Ser1943, as a key factor contributing to the radiation-induced senescence of hMSC. We showed that individual knockdown of CK2 catalytic subunits CK2α and CK2α′ induced hMSC senescence. However, only knockdown of CK2α resulted in morphologic phenotypes resembling those of radiation-induced senescence. These results suggest that CK2α and CK2α′ play differential roles in hMSC senescence progression, and their relative expression might represent a novel regulatory mechanism for CK2 activity. [Cancer Res 2009;69(20):8200–7]
Direct Evidence that Bevacizumab, an Anti-VEGF Antibody, Up-regulates SDF1α, CXCR4, CXCL6, and Neuropilin 1 in Tumors from Patients with Rectal Cancer
Authors: Xu Lei , Duda Dan G. , di Tomaso Emmanuelle , Ancukiewicz Marek , Chung Daniel C. , Lauwers Gregory Y. , Samuel Rekha , Shellito Paul , Czito Brian G. , Lin Pei-Chun , Poleski Martin , Bentley Rex , Clark Jeffrey W. , Willett Christopher G. , Jain Rakesh K. 
Published: October 2009

Abstract
Clinical studies converge on the observation that circulating cytokines are elevated in most cancer patients by anti–vascular endothelial growth factor (VEGF) therapy. However, the source of these molecules and their relevance in tumor escape remain unknown. We examined the gene expression profiles of cancer cells and tumor-associated macrophages in tumor biopsies before and 12 days after monotherapy with the anti-VEGF antibody bevacizumab in patients with rectal carcinoma. Bevacizumab up-regulated stromal cell–derived factor 1α (SDF1α), its receptor CXCR4, and CXCL6, and down-regulated PlGF, Ang1, and Ang2 in cancer cells. In addition, bevacizumab decreased Ang1 and induced neuropilin 1 (NRP1) expression in tumor-associated macrophages. Higher SDF1α plasma levels during bevacizumab treatment significantly associated with distant metastasis at three years. These data show that VEGF blockade up-regulates inflammatory pathways and NRP1, which should be evaluated as potential targets for improving anti-VEGF therapy. [Cancer Res 2009;69(20):7905–10]
HDAC Inhibitor SNDX-275 Induces Apoptosis in erbB2-Overexpressing Breast Cancer Cells via Down-regulation of erbB3 Expression
Authors: Huang Xiaoping , Gao Lizhi , Wang Shuiliang , Lee Choon-Kee , Ordentlich Peter , Liu Bolin 
Published: October 2009

Abstract
Breast cancer is a highly heterogeneous disease with distinct histologic subtypes. Targeted therapies such as endocrine therapy and growth factor receptor inhibitors have had a significant impact on the treatment of metastatic breast cancer patients. Unfortunately, resistance to these agents eventually occurs, and currently represents a significant clinical problem in the management of breast cancers. Inhibitors of histone deacetylases (HDACi) exhibit anticancer activity in a variety of tumor cell models and have been shown to target mechanisms of resistance to a number of targeted agents. It is unclear, however, if there are specific breast cancer subtypes for which an HDACi may be more or less effective. Here, we report that the class I isoform–selective HDACi entinostat (SNDX-275) preferentially inhibits cell proliferation/survival and inactivates downstream signaling in erbB2-overexpressing compared with basal breast cancer cells. SNDX-275 reduces the levels of both erbB2 and erbB3, as well as significantly decreases P-erbB2, P-erbB3, P-Akt, and P-MAPK in erbB2-overexpressing cells. Additionally, SNDX-275 promotes apoptosis and induces cell cycle arrest predominantly at G1 phase in erbB2-overexpressing cells, whereas SNDX-275 mainly induces G2-M arrest in basal breast cancer cells. The cellular bias of SNDX-275 is shown to be related partly to the levels of erbB3 expression that directly impact the ability of SNDX-275 to inhibit proliferation/survival of the erbB2-overexpressing breast cancer cells. These findings show that SNDX-275 may be developed as a novel therapeutic agent to treat breast cancers with coexpression of both erbB2 and erbB3. [Cancer Res 2009;69(21):8403–11]
SC68896, a Novel Small Molecule Proteasome Inhibitor, Exerts Antiglioma Activity In vitro and In vivo
Authors: Roth Patrick , Kissel Maria , Herrmann Caroline , Eisele Günter , Leban Johann , Weller Michael , Schmidt Friederike 
Published: October 2009

Abstract
Purpose: Glioblastomas are among the most lethal neoplasms, with a median survival of &lt;1 year. Modulation of the proteasome function has emerged as a novel approach to cancer pharmacotherapy. Here, we characterized the antitumor properties of SC68896, a novel small molecule proteasome inhibitor.
Experimental Design: Different tumor cell lines were tested by crystal violet staining for sensitivity to SC68896, given alone or in combination with death ligands. The molecular mechanisms mediating SC68896-induced cell death and changes in cell cycle progression were assessed by immunoblot and flow cytometry. An orthotopic human glioma xenograft model in nude mice was used to examine the in vivo activity of SC68896.
Results: SC68896 inhibits the proliferation of cell lines of different types of cancer, including malignant glioma. Exposure of LNT-229 glioma cells to SC68896 results in a concentration- and time-dependent inhibition of the proteasome, with a consequent accumulation of p21 and p27 proteins, cell cycle arrest, caspase cleavage, and induction of apoptosis. Using RNA interference, we show that the effect of SC68896 on glioma cells is facilitated by wild-type p53. SC68896 sensitizes glioma cells to tumor necrosis factor–related apoptosis–inducing ligand and CD95 ligand and up-regulates the cell surface expression of the tumor necrosis factor–related apoptosis–inducing ligand receptor cell death receptors 4 and 5, which may contribute to this sensitization. Intracerebral glioma–bearing nude mice treated either i.p. or intratumorally with SC68896 experience prolonged survival.
Conclusions: SC68896 is the first proteasome inhibitor that exerts antiglioma activity in vivo. It may represent a novel prototype agent for the treatment of malignant gliomas and warrants clinical evaluation. (Clin Cancer Res 2009;15(21):6609–18)
Mammary-Derived Growth Inhibitor Alters Traffic of EGFR and Induces a Novel Form of Cetuximab Resistance
Authors: Nevo Jonna , Mattila Elina , Pellinen Teijo , Yamamoto Daniel L. , Sara Henri , Iljin Kristiina , Kallioniemi Olli , Bono Petri , Heikkilä Päivi , Joensuu Heikki , Wärri Anni , Ivaska Johanna 
Published: October 2009

AbstractPurpose: Only few predictive factors for the clinical activity of anti–epidermal growth factor receptor (EGFR) therapy are available. Mammary-derived growth inhibitor (MDGI) is a small cytosolic protein suggested to play a role in the differentiation of epithelial cells. Here, we have investigated the effect of MDGI expression on the EGFR signaling and cetuximab responsiveness of cancer cells.Experimental Design: MDGI mRNA expression was investigated in clinical breast and lung cancer samples and in nontransformed and malignant cell lines. The effect of ectopic expression of MDGI on EGFR, ErbB2, and integrin function and traffic was investigated in breast and lung cancer cell lines using multiple methods. The effect of anti-EGFR agents on these cells were tested by cell proliferation measurements and by assessing tumor growth of breast cancer cells in cetuximab treated and control athymic nude mice.Results: Here, we show that although MDGI is absent in cultured cell lines because of epigenetic silencing, MDGI mRNA is expressed in 40% of clinical breast carcinomas and 85% of lung cancers. Ectopic expression of MDGI rendered breast and lung cancer cells resistant to the anti-EGFR antibody cetuximab in vitro and in an orthotopic breast cancer xenograft model in vivo. When expressed in cancer cells, MDGI induces intracellular accumulation of EGFR, but not ErbB2, and the internalized receptor is phosphorylated and not degraded.Conclusions: MDGI-driven inherent desensitization of cancer cells is a novel molecular mechanism for resistance to the anti-EGFR antibody therapy, and MDGI may be a biomarker for responsiveness to anti-EGFR antibody therapy.(Clin Cancer Res 2009;15(21):6570–81)
Recombinant Peptides as Biomarkers for Tumor Response to Molecular Targeted Therapy
Authors: Passarella Ralph J. , Zhou Li , Phillips John G. , Wu Hongmei , Hallahan Dennis E. , Diaz Roberto 
Published: October 2009

Abstract
Purpose: Phage display technology can be used to identify peptide sequences that bind rapidly and specifically to tumors responding to sunitinib therapy. These peptides may help to address problems with current methods of assessing tumor response to therapy that can be slow and have limited usage.
Experimental Design: The peptide of interest was isolated after four rounds of biopanning in MDA-MB-231 and MCF-7 xenografted tumors. The binding location of the peptide was investigated with immunohistochemistry. Its in vivo ability to bind to breast tumors responding to therapy was determined by treating nude mice, xenografted with various tumor cell lines, with sunitinib and using near IR imaging to assess the ability of the peptide conjugated to Alexafluor-750 to bind tumors.
Results: EGEVGLG was the dominant sequence isolated from biopanning. This peptide showed increased binding relative to control groups in two cancer cell lines (MDA-MB-435 and MCF-7 human breast) responding to sunitinib treatment, whereas no elevated binding occurred in vitro when samples were incubated with tumor cells that are unresponsive to sunitinib treatment (B16 melanoma and BxPC3 pancreatic). Mice xenografted with tumors that are responsive to sunitinib therapy showed increased peptide binding when compared with untreated control. Mice bearing tumors unresponsive to sunitinib therapy showed no increased peptide binding between treated and untreated groups.
Conclusion: The use of recombinant peptides to assess the pharmacodynamic response of cancer holds promise in minimizing the duration of ineffective treatment regimens in patients, potentially providing a more rapid and less invasive assessment of cancer response to systemic therapy. (Clin Cancer Res 2009;15(20):6421–9)
Clinical Predictors and Algorithm for the Genetic Diagnosis of Pheochromocytoma Patients
Authors: Erlic Zoran , Rybicki Lisa , Peczkowska Mariola , Golcher Henriette , Kann Peter H. , Brauckhoff Michael , Müssig Karsten , Muresan Michaela , Schäffler Andreas , Reisch Nicole , Schott Matthias , Fassnacht Martin , Opocher Giuseppe , Klose Silke , Fottner Christian , Forrer Flavio , Plöckinger Ursula , Petersenn Stephan , Zabolotny Dimitry , Kollukch Oleg , Yaremchuk Svetlana , Januszewicz Andrzej , Walz Martin K. , Eng Charis , Neumann Hartmut P.H. ,   for the European-American Pheochromocytoma Study Group
Published: October 2009

Abstract
Purpose: Six pheochromocytoma susceptibility genes causing distinct syndromes have been identified; approximately one of three of all pheochromocytoma patients carry a predisposing germline mutation. When four major genes (VHL, RET, SDHB, SDHD) are analyzed in a clinical laboratory, costs are ∼$3,400 per patient. The aim of the study is to systematically obtain a robust algorithm to identify who should be genetically tested, and to determine the order in which genes should be tested.
Experimental Design: DNA from 989 apparently nonsyndromic patients were scanned for germline mutations in the genes VHL, RET, SDHB, SDHC, and SDHD. Clinical parameters were analyzed as potential predictors for finding mutations by multiple logistic regression, validated by bootstrapping. Cost reduction was calculated between prioritized gene testing compared with that for all genes.
Results: Of 989 apparently nonsyndromic pheochromocytoma cases, 187 (19%) harbored germline mutations. Predictors for presence of mutation are age &lt;45 years, multiple pheochromocytoma, extra-adrenal location, and previous head and neck paraganglioma. If we used the presence of any one predictor as indicative of proceeding with gene testing, then 342 (34.6%) patients would be excluded, and only 8 carriers (4.3%) would be missed. We were also able to statistically model the priority of genes to be tested given certain clinical features. E.g., for patients with prior head and neck paraganglioma, the priority would be SDHD&gt;SDHB&gt;RET&gt;VHL. Using the clinical predictor algorithm to prioritize gene testing and order, a 44.7% cost reduction in diagnostic process can be achieved.
Conclusions: Clinical parameters can predict for mutation carriers and help prioritize gene testing to reduce costs in nonsyndromic pheochromocytoma presentations. (Clin Cancer Res 2009;15(20):6378–85)
Tumor-Expressed B7-H1 and B7-DC in Relation to PD-1+ T-Cell Infiltration and Survival of Patients with Cervical Carcinoma
Authors: Karim Rezaul , Jordanova Ekaterina S. , Piersma Sytse J. , Kenter Gemma G. , Chen Lieping , Boer Judith M. , Melief Cornelis J. M. , van der Burg Sjoerd H. 
Published: October 2009

Abstract
Purpose: The interaction between programmed cell death 1 (PD-1), expressed by activated effector or regulatory T cells, and B7-H1 (PD-L1) and B7-DC (PD-L2) results in the inhibition of T-cell function. The aim of this study was to determine B7-H1, B7-DC, and PD-1 expression in cervical carcinoma.
Experimental Design: A tissue microarray of a well-defined group of 115 patients was stained with antibodies against B7-H1 and B7-DC. Three-color fluorescent immunohistochemistry was used to study the number and phenotype of tumor-infiltrating T cells expressing PD-1. Additional analyses consisted of in vitro T-cell suppression assays.
Results: B7-H1 was expressed in 19%, and B7-DC was expressed by 29% of the 115 tumors. PD-1 was expressed by more than half of both the infiltrating CD8+ T cells and CD4+Foxp3+ T cells, irrespective of B7-H1 or B7-DC expression by tumors. The expression of B7-H1 did not show a direct impact on patient survival. However, subgroup analysis revealed that patients with a relative excess of infiltrating regulatory T cells displayed a better survival when the tumor was B7-H1 positive (P = 0.033). Additional studies showed that the presence of B7-H1 during the activation of CD4+Foxp3+ regulatory T cells impaired their suppressive function in a functional in vitro assay.
Conclusions: B7-H1 is expressed on only a minority of cervical cancers and does not influence the survival of patients with cervical cancer. PD-1 is expressed by a vast number of infiltrating CD8 T cells, suggesting that blocking of PD-1 could have therapeutic potential in cervical cancer patients. (Clin Cancer Res 2009;15(20):6341–7)
Phenotypic Knockout of CXCR4 by a Novel Recombinant Protein TAT/54R/KDEL Inhibits Tumors Metastasis
Authors: Ma Wei-Feng , Du Jun , Fu Liu-Peng , Fang Rui , Chen Hong-Yuan , Cai Shao-Hui 
Published: October 2009

Abstract
The chemokine receptor, CXCR4, and its specific ligand, CXCL12, have been proven to regulate the directional trafficking and invasion of breast cancer cells to sites of metastases, and similar phenomena have also been identified in many malignant tumors that aberrantly overexpress CXCR4. Therefore, blocking the interaction between CXCR4 and CXCL12 is considered a possible approach to efficiently prevent cancer metastasis. Employing a cellular phenotypic knockout strategy based on intrakines, we developed a novel recombinant chimeric protein, TAT/54R/KDEL, which contains three distinct functional domains: CXCL12/54R, a mutant of CXCL12 with CXCR4 antagonism, as well as HIV-derived TAT (47-57) and an endoplasmic reticulum retention four-peptide sequence KDEL that links at its NH2 and COOH termini, respectively. Using the MOLT-4 cell line, which expressed CXCR4 highly and stably in vitro, we determined that TAT/54R/KDEL was able to efficiently transfer into the endoplasmic reticulum of tumor cells, where it specifically binds to the newly synthesized CXCR4 and prevents the latter from reaching the surface. Chemotaxis assays showed that the cells treated with TAT/54R/KDEL failed to migrate toward CXCL12. Furthermore, we observed that the systemic treatment of TAT/54R/KDEL could impair lung metastasis in a highly metastatic mammary cancer cell line, 4T1 cells, with the decrease of CXCR4 on their membrane. Our results suggest that the phenotypic knockout strategy of CXCR4 using a novel recombinant protein TAT/54R/KDEL might be a possible approach for inhibiting relative tumor metastasis mediated by CXCR4/CXCL12 interaction. (Mol Cancer Res 2009;7(10):1613–21)
Mutant p53 (G199V) Gains Antiapoptotic Function through Signal Transducer and Activator of Transcription 3 in Anaplastic Thyroid Cancer Cells
Authors: Kim Tae-Hyun , Lee Sang Yull , Rho Jee Hyun , Jeong Na Young , Soung Young Hwa , Jo Wol Soon , Kang Do-Young , Kim Sung-Heun , Yoo Young Hyun 
Published: October 2009

Abstract
In the present study, we identified a missense mutation (G199V) in KAT-18 cell line established from primary cultures of anaplastic thyroid cancer (ATC). Notably, knockdown of this mutant (mt) p53 reduced cell viability and exerted antitumor activity equivalent to high doses of several chemotherapeutic agents. We showed that p53 knockdown had an antitumor effect via the induction of apoptosis. We further examined the underlying mechanism by which mt p53 (G199V) gains antiapoptotic function in KAT-18 cells. Microarray analysis revealed that p53 knockdown modified the expression of numerous apoptosis-related genes. Importantly, p53 knockdown led to downregulation of signal transducer and activator of transcription-3 (STAT3) gene expression. We further observed that p53 knockdown induced the downregulation of STAT3 protein. We also observed that a STAT3 inhibitor augmented the reduction of cell viability induced by p53 knockdown, whereas interleukin-6 treatment alleviated this effect. In addition, overexpression of STAT3 protected ATC cells against cell death induced by p53 knockdown. Taken together, these data show that mt p53 (G199V) gains antiapoptotic function mediated by STAT3 in ATC cells. Inhibition of the function of mt p53 (G199V) could be a novel and useful therapeutic strategy for decreasing the extent and severity of toxicity due to chemotherapeutic agents. (Mol Cancer Res 2009;7(10):1645–54)