bluuebunny/crossref_metadata_2025_split huggingface dataset:
Normal Cells Control the Growth of Neighboring Transformed Cells Independent of Gap Junctional Communication and Src Activity
Authors: Alexander David B. , Ichikawa Hitoshi , Bechberger John F. , Valiunas Virginijus , Ohki Misao , Naus Christian C. G. , Kunimoto Takehiko , Tsuda Hiroyuki , Miller W. Todd , Goldberg Gary S. 
Published: September 2005

Abstract
The growth of many types of cancer cells can be controlled by surrounding normal cells. However, mechanisms underlying this phenomenon have not been defined. We used a layered culture system to investigate how nontransformed cells suppress the growth of neighboring transformed cells. Direct physical contact between transformed and nontransformed cells was required for growth suppression of transformed cells in this system; communication by diffusible factors was not sufficient. However, significant gap junctional communication was not required, indicating that other intercellular junctions mediated this growth regulatory response. We also report that the Src kinase activity in transformed cells was not directly inhibited by contact with nontransformed cells. Instead, nontransformed cells increased the expression of serum deprivation-response protein and the transcription factor four and a half LIM domain 1 in tumor cells. In addition, these results suggest mechanisms by which normal cells may block Wnt signaling, inhibit insulin-like growth factor activity, and promote host recognition of neighboring tumor cells.
Control of Radiosensitivity of F9 Mouse Teratocarcinoma Cells by Regulation of Histone
H2AX
Gene Expression using a Tetracycline Turn-Off System
Authors: Yoshida Kayo , Morita Takashi 
Published: September 2005

Abstract
The mouse histone H2AX has unique COOH-terminal serine residues that are phosphorylated in response to double-strand DNA breaks introduced by ionizing radiation. This suggests that H2AX acts to maintain genomic stability. We constructed a tetracycline (tet)-directed turn-off vector and integrated it into F9 mouse teratocarcinoma cells by homologous recombination. In homozygously recombined cells, expression of the histone H2AX gene was repressed to 0.02% of the expression observed in wild-type cells by the addition of doxycycline, an analog of tet. Sensitivity of cells with repressed H2AX expression to X-irradiation was increased 1.95×, indicating that DNA repair was impaired by repression of H2AX. When we s.c. injected tet-regulated F9 cells into the flanks of mice, tumor growth was slightly suppressed by X-irradiation in H2AX-repressed tumors, whereas without X-irradiation, tumor growth did not differ by H2AX status. Thus, H2AX might be a potential molecular target for sensitizing cancer cells to radiotherapy to minimize required irradiation doses.
Loss of Heterozygosity and Its Correlation with Expression Profiles in Subclasses of Invasive Breast Cancers
Authors: Wang Zhigang C. , Lin Ming , Wei Lee-Jen , Li Cheng , Miron Alexander , Lodeiro Gabriella , Harris Lyndsay , Ramaswamy Sridhar , Tanenbaum David M. , Meyerson Matthew , Iglehart James D. , Richardson Andrea 
Published: September 2005

Abstract
Gene expression array profiles identify subclasses of breast cancers with different clinical outcomes and different molecular features. The present study attempted to correlate genomic alterations (loss of heterozygosity; LOH) with subclasses of breast cancers having distinct gene expression signatures. Hierarchical clustering of expression array data from 89 invasive breast cancers identified four major expression subclasses. Thirty-four of these cases representative of the four subclasses were microdissected and allelotyped using genome-wide single nucleotide polymorphism detection arrays (Affymetrix, Inc.). LOH was determined by comparing tumor and normal single nucleotide polymorphism allelotypes. A newly developed statistical tool was used to determine the chromosomal regions of frequent LOH. We found that breast cancers were highly heterogeneous, with the proportion of LOH ranging widely from 0.3% to &gt;60% of heterozygous markers. The most common sites of LOH were on 17p, 17q, 16q, 11q, and 14q, sites reported in previous LOH studies. Signature LOH events were discovered in certain expression subclasses. Unique regions of LOH on 5q and 4p marked a subclass of breast cancers with “basal-like” expression profiles, distinct from other subclasses. LOH on 1p and 16q occurred preferentially in a subclass of estrogen receptor-positive breast cancers. Finding unique LOH patterns in different groups of breast cancer, in part defined by expression signatures, adds confidence to newer schemes of molecular classification. Furthermore, exclusive association between biological subclasses and restricted LOH events provides rationale to search for targeted genes.
Effector Cell-Derived Lymphotoxin α and Fas Ligand, but not Perforin, Promote Tc1 and Tc2 Effector Cell-Mediated Tumor Therapy in Established Pulmonary Metastases
Authors: Dobrzanski Mark J. , Reome Joyce B. , Hollenbaugh Joseph A. , Hylind James C. , Dutton Richard W. 
Published: September 2005

AbstractCytolytic CD8+ effector cells fall into two subpopulations based on cytokine secretion. Type 1 CD8+ T cells (Tc1) secrete IFN-γ, whereas type 2 CD8+ T cells (Tc2) secrete interleukin (IL)-4 and IL-5. Although both effector cell subpopulations display Fas ligand (FasL) and tumor necrosis factor (TNF), tumor lysis is predominantly perforin dependent in vitro. Using an ovalbumin-transfected B16 lung metastasis model, we show that heightened numbers of adoptively transferred ovalbumin-specific Tc1 and Tc2 cells accumulated at the tumor site by day 2 after therapy and induced tumor regression that enhanced survival in mice with pulmonary metastases. Transfer of either TNF-α- or perforin-deficient Tc1 or Tc2 effector cells generated from specified gene-deficient mice showed no differences in therapeutic efficiency when compared with corresponding wild-type cells. In contrast, both Tc1 and Tc2 cells, derived from either FasL or TNF-α/lymphotoxin (LT) α double knockout mice, showed that therapeutic effects were dependent, in part, on effector cell-derived FasL or LTα. Six days after effector cell therapy, elevated levels of activated endogenous CD8/CD44High and CD4/CD44High T cells localized and persisted at sites of tumor growth, whereas donor cell numbers concomitantly decreased. Both Tc1 and Tc2 effector cell subpopulations induced endogenous antitumor responses that were dependent, in part, on recipient-derived IFN-γ and TNF-α. However, neither effector cell-mediated therapy was dependent on recipient-derived perforin, IL-4, IL-5, or nitric oxide. Collectively, tumor antigen-specific Tc1 and Tc2 effector cell-mediated therapy is initially dependent, in part, on effector cell-derived FasL or LTα that may subsequently potentiate endogenous recipient-derived type 1 antitumor responses dependent on TNF-α and IFN-γ.
Effects of Dexamethasone or Celecoxib on Biliary Toxicity after Hepatic Arterial Infusion of 5-Fluorodeoxyuridine in a Canine Model
Authors: Ensminger William , Knol James , DeRemer Susan , Wilkinson Erby , Walker Suzette , Williams David , Maybaum Jonathan 
Published: September 2005

Abstract
Previous work has shown that in humans the dose-limiting toxicity for fluorodeoxyuridine [2-fluoro-5′-deoxyuridine (FdUrd)] when administered by hepatic arterial infusion is biliary sclerosis. The current study was undertaken to attempt to modify this toxicity in a canine model that has been demonstrated to closely mimic the clinical situation. Unlike previous studies using this model, in which animals were sacrificed after extensive fibrosis had already occurred, the current experiments were designed so that observations of pathology were made at an earlier time, when the initial inflammatory injury underlying the fibrotic process was still taking place. Implantable pumps were used to deliver FdUrd into the hepatic artery of animals at a rate of 0.3 mg/kg/day in the presence or absence of 10 mg/week dexamethasone or 100 mg/day of celecoxib for 35 days, at which time the animals were beginning to show signs of toxicity. After evaluation for radiological evidence of biliary obstruction, the animals were sacrificed and portions of their livers were processed for examination of microscopic pathology and 2-bromo-5′deoxyuridine labeling index. Dexamethasone treatment protected the animals from biliary sclerosis determined radiologically, further validating this model as being representative of the response in humans. Similarly the Cox-2 inhibitor, celecoxib, appeared to provide protection against radiological changes of biliary stricture, although possibly to a lesser degree than the resultant from dexamethasone. In addition, FdUrd treatment caused elevation of the DNA 2-bromo-5′deoxyuridine labeling index above control levels in biliary epithelial cells. Dexamethasone and celecoxib each significantly attenuated the FdUrd-induced elevation of DNA labeling index in biliary epithelium. These findings demonstrate the usefulness of this canine model for studying the mechanisms of drug-induced biliary sclerosis and reinforce the hypothesis that blocking inflammation may retard the progression of injury that eventually leads to fibrosis. This study suggests that clinical testing of celecoxib as a preventive for hepatic arterial-FdUrd induced biliary damage could prove valuable.
RTVP-1, a Tumor Suppressor Inactivated by Methylation in Prostate Cancer
Authors: Ren Chengzhen , Li Likun , Yang Guang , Timme Terry L. , Goltsov Alexei , Ren Chenghui , Ji Xiaorong , Addai Josephine , Luo Hongbin , Ittmann Michael M. , Thompson Timothy C. 
Published: September 2005

Abstract
We previously identified and characterized a novel p53-regulated gene in mouse prostate cancer cells that was homologous to a human gene that had been identified in brain cancers and termed RTVP-1 or GLIPR. In this report, we document that the human RTVP-1 gene is also regulated by p53 and induces apoptosis in human prostate cancer cell lines. We show that the expression of the human RTVP-1 gene is down-regulated in human prostate cancer specimens compared with normal human prostate tissue at the mRNA and protein levels. We further document epigenetic changes consistent with RTVP-1 being a tumor suppressor in human prostate cancer.
Selective Usage of D-Type Cyclins by Ewing’s Tumors and Rhabdomyosarcomas
Authors: Zhang Jingsong , Hu Siwen , Schofield Deborah E. , Sorensen Poul H. B. , Triche Timothy J. 
Published: September 2005

Abstract
The genetic mechanisms that control proliferation of childhood musculoskeletal malignancies, notably Ewing’s tumor (ET) and rhabdomyosarcoma (RMS), remain largely unknown. Most human cancers appear to overexpress at least one of the G1 cyclins (cyclins D1, D2, D3, E1, and E2) to bypass normal regulation of cell cycle G1 progression. We compared the gene expression profiles of 7 ET and 13 RMS primary tumor samples and found overexpression of cyclin D1 in all 7 ET samples. In contrast, RMS samples expressed higher levels of cyclin D2, cyclin D3, and cyclin E1. This was confirmed by quantitative reverse transcription-polymerase chain reaction and Western blot. The relative roles of RAS-extracellular signal-regulated kinase 1/2 and phosphatidylinositol 3′-kinase (PI3K)-AKT pathways in the regulation of D-type cyclin expression in these tumors were then assessed. Inhibition of either pathway reduced expression of cyclins D1, D2, and D3 in RMS lines, whereas only PI3K inhibitors blocked cyclin D1, D2, and D3 expression in ET lines. Furthermore, PI3K-AKT appeared to regulate D-type cyclin transcription in RMS lines through FKHR and FKHRL1. Finally, the role of the ET-associated EWS-FLI1 fusion gene in regulating D cyclin expression was studied. Inhibition of EWS-FLI1 expression in the TC71 ET line decreased cyclin D1 levels but increased cyclin D3 levels. In contrast, induction of EWS-FLI1 expression in the RD RMS cell line increased cyclin D1 expression but decreased cyclin D3 expression. Our results demonstrate distinct regulation of D-type cyclins in ET and RMS and indicate that EWS-FLI1 can modulate the expression of D-type cyclins independent of cellular backgrounds.
Inhibition of Metastasis of Tumor Cells Overexpressing Thymidine Phosphorylase by 2-Deoxy-l-Ribose
Authors: Nakajima Yuichi , Gotanda Takenari , Uchimiya Hiroshi , Furukawa Tatsuhiko , Haraguchi Misako , Ikeda Ryuji , Sumizawa Tomoyuki , Yoshida Hiroki , Akiyama Shin-ichi 
Published: September 2005

Abstract
Thymidine phosphorylase (TP) catalyzes the reversible conversion of thymidine to thymine, thereby generating 2-deoxy-d-ribose-1-phosphate, which upon dephosphorylation forms 2-deoxy-d-ribose (d-dRib), a degradation product of thymidine. We have previously shown that d-dRib promotes angiogenesis and chemotaxis of endothelial cells and also confers resistance to hypoxia-induced apoptosis in some cancer cell lines. 2-Deoxy-l-ribose (l-dRib), a stereoisomer of d-dRib, can inhibit d-dRib anti-apoptotic effects and suppressed the growth of KB cells overexpressing TP (KB/TP cells) transplanted into nude mice. In this study, we examined the ability of l-dRib to suppress metastasis of KB/TP cells using two different models of metastasis. The antimetastatic effect of l-dRib was first investigated in a liver-metastasis model in nude mice inoculated with KB/TP cells. Oral administration of l-dRib for 28 days at a dose of 20 mg/kg/day significantly reduced the number of metastatic nodules in the liver and suppressed angiogenesis and enhanced apoptosis in KB/TP metastatic nodules. Next, we compared the ability of l-dRib and tegafur alone or in combination to decrease the number of metastatic nodules in organs in the abdominal cavity in nude mice receiving s.c. of KB/TP cells into their backs. l-dRib (20 mg/kg/day) was significantly (P &lt; 0.05) more efficient than tegafur (100 mg/kg/day) in decreasing the number of metastatic nodules in organs in the abdominal cavity. By in vitro invasion assay, l-dRib also reduced the number of invading KB/TP cells. l-dRib anti-invasive activity may be mediated by its ability to suppress the enhancing effect of TP and d-dRib on both mRNA and protein expression of vascular endothelial growth factor and interleukin-8 in cultured KB cells. These findings suggest that l-dRib may be useful in a clinical setting for the suppression of metastasis of tumor cells expressing TP.
Moderate Hypermutability of a Transgenic
lacZ
Reporter Gene in
Myc
-Dependent Inflammation-Induced Plasma Cell Tumors in Mice
Authors: Felix Klaus , Polack Axel , Pretsch Walter , Jackson Sharon H. , Feigenbaum Lionel , Bornkamm Georg-Wilhelm , Janz Siegfried 
Published: September 2005

Abstract
Mutator phenotypes, a common and largely unexplained attribute of human cancer, might be better understood in mouse tumors containing reporter genes for accurate mutation enumeration and analysis. Previous work on peritoneal plasmacytomas (PCTs) in mice suggested that PCTs have a mutator phenotype caused by Myc-deregulating chromosomal translocations and/or phagocyte-induced mutagenesis due to chronic inflammation. To investigate this hypothesis, we generated PCTs that harbored the transgenic shuttle vector, pUR288, with a lacZ reporter gene for the assessment of mutations in vivo. PCTs exhibited a 5.5 times higher mutant frequency in lacZ (40.3 ± 5.1 × 10−5) than in normal B cells (7.36 ± 0.77 × 10−5), demonstrating that the tumors exhibit the phenotype of increased mutability. Studies on lacZ mutant frequency in serially transplanted PCTs and phagocyte-induced lacZ mutations in B cells in vitro indicated that mutant levels in tumors are not determined by exogenous damage inflicted by inflammatory cells. In vitro studies with a newly developed transgenic model of inducible Myc expression (Tet-off/MYC) showed that deregulated Myc sensitizes B cells to chemically induced mutations, but does not cause, on its own, mutations in lacZ. These findings suggested that the hypermutability of PCT is governed mainly by intrinsic features of tumor cells, not by deregulated Myc or chronic inflammation.
Proceedings of the Oxygen Homeostasis/Hypoxia Meeting
Authors: Kaufman Bennett , Scharf Orit , Arbeit Jeffrey , Ashcroft Margaret , Brown J. Martin , Bruick Richard K. , Chapman J. Donald , Evans Sydney M. , Giaccia Amato J. , Harris Adrian L. , Huang Eric , Johnson Randall , Kaelin William , Koch Cameron J. , Maxwell Patrick , Mitchell James , Neckers Len , Powis Garth , Rajendran Joseph , Semenza Gregg L. , Simons Jonathan , Storkebaum Erik , Welch Michael J. , Whitelaw Murray , Melillo Giovanni , Ivy S. Percy 
Published: September 2005

Abstract
The first Oxygen Homeostasis/Hypoxia Meeting was held on February 12, 2003, at the Sheraton National Hotel, Washington, D.C. The meeting was hosted by Drs. S. Percy Ivy and Giovanni Melillo of the National Cancer Institute, NIH. The purpose of the meeting was to stimulate collaborations among the participants who are engaged in different areas of hypoxia research and application, including basic research on hypoxia, and its induction and consequences; the development of drugs targeting hypoxia and factors involved in pathways leading to (or controlled by) hypoxia; and the development and application of hypoxia imaging techniques and reagents.
HOXB13 Homeodomain Protein Suppresses the Growth of Prostate Cancer Cells by the Negative Regulation of T-Cell Factor 4
Authors: Jung Chaeyong , Kim Ran-Sook , Lee Sang-Jin , Wang Chihuei , Jeng Meei-Huey 
Published: September 2005

Abstract
In prostate gland, HOXB13 is highly expressed from the embryonic stages to adulthood. However, the function of HOXB13 in normal cell growth and tumorigenesis is not yet known. We investigated the role of HOXB13 and mechanism by which it functions in HOXB13-negative cells. Expression of HOXB13 was forced in HOXB13-negative PC3 prostate cancer cells using a liposome-mediated gene transfer approach. Compared with the control clones, HOXB13-expressing PC3 cells exhibited significant inhibition of in vitro and in vivo cell growth with G1 cell cycle arrest mediated by the suppression of cyclin D1 expression. Because cyclin D1 is mainly regulated by β-catenin/T-cell factor (TCF), TCF-4 response element was used in a reporter gene transcription assay, demonstrating that HOXB13 significantly inhibits TCF-4-mediated transcriptional activity in both prostate and nonprostate cells. This inhibition occurred in a dose-responsive manner and was specific to TCF-4 response element. Western blot analysis demonstrated that HOXB13 down-regulates the expression of TCF-4 and its responsive genes, c-myc and cyclin D1. HOXB13 also suppressed the activity of natural c-myc promoter. This study suggests that HOXB13, a transcription factor, functions as a cell growth suppressor by negatively regulating the expression of TCF-4, which eventually provides negative signals for cell proliferation. This observation will provide valuable insight into the molecular basis of prostate tumorigenesis.
Identification of the E1A-Regulated Transcription Factor p120E4F as an Interacting Partner of the RASSF1A Candidate Tumor Suppressor Gene
Authors: Fenton Sarah L. , Dallol Ashraf , Agathanggelou Angelo , Hesson Luke , Ahmed-Choudhury Jalal , Baksh Shairaz , Sardet Claude , Dammann Reinhard , Minna John D. , Downward Julian , Maher Eamonn R. , Latif Farida 
Published: September 2005

Abstract
Epigenetic inactivation of the candidate tumor suppressor gene RASSF1A is a frequent and critical event in the pathogenesis of many human cancers. The RASSF1A protein contains a Ras association domain, suggesting a role in Ras-like signaling pathways, and has also been implicated in cell cycle progression. However, the preliminary data suggests that the RASSF1A gene product is likely to have multiple functions. To identify novel RASSF1A functions, we have sought to identify interacting proteins by yeast two-hybrid analysis in a human brain cDNA library. We identified the E1A-regulated transcription factor p120E4F as a RASSF1A interacting partner in yeast and mammalian cells, and demonstrated that RASSF1A protein and p120E4F form a complex in vivo. The interaction between RASSF1A and p120E4F was confirmed by both in vitro and in vivo pull downs and coimmunoprecipitation assays. In addition, specific inactivation of RASSF1A by short interfering RNA disrupts binding of RASSF1A to p120E4F in coimmunoprecipitation assays. In addition, we demonstrated enhanced G1 cell cycle arrest and S phase inhibition by propidium iodide staining of p120E4F in the presence of RASSF1A. As p120E4F has been reported previously to interact with p14ARF, retinoblastoma, and p53, these findings provide an important link between the function of RASSF1A and other major human tumor suppressor genes.
Cotreatment with Histone Deacetylase Inhibitor LAQ824 Enhances Apo-2L/Tumor Necrosis Factor-Related Apoptosis Inducing Ligand-Induced Death Inducing Signaling Complex Activity and Apoptosis of Human Acute Leukemia Cells
Authors: Guo Fei , Sigua Celia , Tao Jianguo , Bali Purva , George Prince , Li Yunqing , Wittmann Sylvie , Moscinski Lynn , Atadja Peter , Bhalla Kapil 
Published: September 2005

Abstract
Present studies demonstrate that treatment with the histone deacetylases inhibitor LAQ824, a cinnamic acid hydroxamate, increased the acetylation of histones H3 and H4, as well as induced p21WAF1 in the human T-cell acute leukemia Jurkat, B lymphoblast SKW 6.4, and acute myelogenous leukemia HL-60 cells. This was associated with increased accumulation of the cells in the G1 phase of the cell cycle, as well as accompanied by the processing and activity of caspase-9 and -3, and apoptosis. Exposure to LAQ824 increased the mRNA and protein expressions of the death receptors DR5 and/or DR4, but reduced the mRNA and protein levels of cellular FLICE-inhibitory protein (c-FLIP). As compared with treatment with Apo-2L/tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) or LAQ824 alone, pretreatment with LAQ824 increased the assembly of Fas-associated death domain and caspase-8, but not of c-FLIP, into the Apo-2L/TRAIL-induced death-inducing signaling complex. This increased the processing of caspase-8 and Bcl-2 interacting domain (BID), augmented cytosolic accumulation of the prodeath molecules cytochrome-c, Smac and Omi, as well as led to increased activity of caspase-3 and apoptosis. Treatment with LAQ824 also down-regulated the levels of Bcl-2, Bcl-xL, XIAP, and survivin. Partial inhibition of apoptosis due to LAQ824 or Apo-2L/TRAIL exerted by Bcl-2 overexpression was reversed by cotreatment with LAQ824 and Apo-2L/TRAIL. Significantly, cotreatment with LAQ824 increased Apo-2L/TRAIL-induced apoptosis of primary acute myelogenous leukemia blast samples isolated from 10 patients with acute myelogenous leukemia. Taken together, these findings indicate that LAQ824 may have promising activity in augmenting Apo-2L/TRAIL-induced death-inducing signaling complex and apoptosis of human acute leukemia cells.