bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Risk Variant in an miR-125b Binding Site in BMPR1B Is Associated with Breast Cancer Pathogenesis
Authors: Sætrom Pål , Biesinger Jacob , Li Sierra M. , Smith David , Thomas Laurent F. , Majzoub Karim , Rivas Guillermo E. , Alluin Jessica , Rossi John J. , Krontiris Theodore G. , Weitzel Jeffrey , Daly Mary B. , Benson Al B. , Kirkwood John M. , O'Dwyer Peter J. , Sutphen Rebecca , Stewart James A. , Johnson David , Larson Garrett P. 
Published: September 2009

Abstract
MicroRNAs regulate diverse cellular processes and play an integral role in cancer pathogenesis. Genomic variation within miRNA target sites may therefore be important sources for genetic differences in cancer risk. To investigate this possibility, we mapped HapMap single nucleotide polymorphisms (SNP) to putative miRNA recognition sites within genes dysregulated in estrogen receptor–stratified breast tumors and used local linkage disequilibirum patterns to identify high-ranking SNPs in the Cancer Genetic Markers of Susceptibility (CGEMS) breast cancer genome-wide association study for further testing. Two SNPs, rs1970801 and rs11097457, scoring in the top 100 from the CGEMS study, were in strong linkage disequilibrium with rs1434536, an SNP that resides within a miR-125b target site in the 3′ untranslated region of the bone morphogenic receptor type 1B (BMPR1B) gene encoding a transmembrane serine/threonine kinase. We validated the CGEMS association findings for rs1970801 in an independent cohort of admixture-corrected cases identified from families with multiple case histories. Subsequent association testing of rs1434536 for these cases and CGEMS controls with imputed genotypes supported the association. Furthermore, luciferase reporter assays and overexpression of miR-125b–mimics combined with quantitative reverse transcription-PCR showed that BMPR1B transcript is a direct target of miR-125b and that miR-125b differentially regulates the C and T alleles of rs1434536. These results suggest that allele-specific regulation of BMPR1B by miR-125b explains the observed disease risk. Our approach is general and can help identify and explain the mechanisms behind disease association for alleles that affect miRNA regulation. [Cancer Res 2009;69(18):7459–65]
mTOR Signal and Hypoxia-Inducible Factor-1α Regulate CD133 Expression in Cancer Cells
Authors: Matsumoto Kazuko , Arao Tokuzo , Tanaka Kaoru , Kaneda Hiroyasu , Kudo Kanae , Fujita Yoshihiko , Tamura Daisuke , Aomatsu Keiichi , Tamura Tomohide , Yamada Yasuhide , Saijo Nagahiro , Nishio Kazuto 
Published: September 2009

Abstract
The underlying mechanism regulating the expression of the cancer stem cell/tumor-initiating cell marker CD133/prominin-1 in cancer cells remains largely unclear, although knowledge of this mechanism would likely provide important biological information regarding cancer stem cells. Here, we found that the inhibition of mTOR signaling up-regulated CD133 expression at both the mRNA and protein levels in a CD133-overexpressing cancer cell line. This effect was canceled by a rapamycin-competitor, tacrolimus, and was not modified by conventional cytotoxic drugs. We hypothesized that hypoxia-inducible factor-1α (HIF-1α), a downstream molecule in the mTOR signaling pathway, might regulate CD133 expression; we therefore investigated the relation between CD133 and HIF-1α. Hypoxic conditions up-regulated HIF-1α expression and inversely down-regulated CD133 expression at both the mRNA and protein levels. Similarly, the HIF-1α activator deferoxamine mesylate dose-dependently down-regulated CD133 expression, consistent with the effects of hypoxic conditions. Finally, the correlations between CD133 and the expressions of HIF-1α and HIF-1β were examined using clinical gastric cancer samples. A strong inverse correlation (r = −0.68) was observed between CD133 and HIF-1α, but not between CD133 and HIF-1β. In conclusion, these results indicate that HIF-1α down-regulates CD133 expression and suggest that mTOR signaling is involved in the expression of CD133 in cancer cells. Our findings provide a novel insight into the regulatory mechanisms of CD133 expression via mTOR signaling and HIF-1α in cancer cells and might lead to insights into the involvement of the mTOR signal and oxygen-sensitive intracellular pathways in the maintenance of stemness in cancer stem cells. [Cancer Res 2009;69(18):7160–4]
Clear Differences in Levels of a Formaldehyde-DNA Adduct in Leukocytes of Smokers and Nonsmokers
Authors: Wang Mingyao , Cheng Guang , Balbo Silvia , Carmella Steven G. , Villalta Peter W. , Hecht Stephen S. 
Published: September 2009

Abstract
Formaldehyde is considered carcinogenic to humans by the IARC, but there are no previous reports of formaldehyde-DNA adducts in humans. In this study, we used liquid chromatography-electrospray ionization-tandem mass spectrometry to quantify the formaldehyde-DNA adduct N6-hydroxymethyldeoxyadenosine (N6-HOMe-dAdo) in leukocyte DNA samples from 32 smokers of ≥10 cigarettes per day and 30 nonsmokers. Clear peaks coeluting with the internal standard in two different systems were seen in samples from smokers but rarely in nonsmokers. N6-HOMe-dAdo was detected in 29 of 32 smoker samples (mean ± SD, 179 ± 205 fmol/μmol dAdo). In contrast, it was detected in only 7 of 30 nonsmoker samples (15.5 ± 33.8 fmol/μmol dAdo; P &lt; 0.001). The results of this study show remarkable differences between smokers and nonsmokers in levels of a leukocyte formaldehyde-DNA adduct, suggesting a potentially important and previously unrecognized role for formaldehyde as a cause of cancer induced by cigarette smoking. [Cancer Res 2009;69(18):7170–4]
Inactivation of the Carney Complex Gene 1 (Protein Kinase A Regulatory Subunit 1A) Inhibits SMAD3 Expression and TGFβ-Stimulated Apoptosis in Adrenocortical Cells
Authors: Ragazzon Bruno , Cazabat Laure , Rizk-Rabin Marthe , Assie Guillaume , Groussin Lionel , Fierrard Hélène , Perlemoine Karine , Martinez Antoine , Bertherat Jérôme 
Published: September 2009

Abstract
The cyclic AMP signaling pathway can be altered at multiple levels in endocrine tumors. Its central component is the protein kinase A (PKA). Carney complex (CNC) is a hereditary multiple neoplasia syndrome resulting from inactivating mutations of the gene encoding the PKA type I α regulatory subunit (PRKAR1A). Primary pigmented nodular adrenocortical disease is the most frequent endocrine tumor of CNC. Transforming growth factor β (TGFβ) regulates adrenal cortex physiology and signals through SMAD2/3. We used an interference approach to test the effects of PRKAR1A inactivation on PKA and TGFβ pathways and on apoptosis in adrenocortical cells. PRKAR1A silencing stimulates PKA activity and increases transcriptional activity of a PKA reporter construct and expression of the endogenous PKA target, NR4A2, under basal conditions or after forskolin stimulation. PRKAR1A inactivation also decreased SMAD3 mRNA and protein levels via PKA, altering the cellular response to TGFβ. SMAD3 expression was also inhibited by adrenocorticorticotropic hormone in the mouse adrenal gland and by forskolin in H295R cells. TGFβ stimulates apoptosis in H295R cells, and this effect was counteracted by PRKAR1A inactivation. PRKAR1A silencing decreased the percentage of apoptotic cells and the cleavage of apoptosis mediators [caspase-3, poly(ADP-ribose) polymerase, and lamin A/C]. Inactivating mutations of PRKAR1A observed in adrenocortical tumors alter SMAD3, leading to resistance to TGFβ-induced apoptosis. This cross-talk between the PKA and the TGFβ signaling pathways reveals a new mechanism of endocrine tumorigenesis. [Cancer Res 2009;69(18):7278–84]
Structural Basis for the Inhibition of Human 5,10-Methenyltetrahydrofolate Synthetase by N10-Substituted Folate Analogues
Authors: Wu Dong , Li Yang , Song Gaojie , Cheng Chongyun , Zhang Rongguang , Joachimiak Andrzej , Shaw Neil , Liu Zhi-Jie 
Published: September 2009

Abstract
5,10-Methenyltetrahydrofolate synthetase (MTHFS) regulates the flow of carbon through the one-carbon metabolic network, which supplies essential components for the growth and proliferation of cells. Inhibition of MTHFS in human MCF-7 breast cancer cells has been shown to arrest the growth of cells. Absence of the three-dimensional structure of human MTHFS (hMTHFS) has hampered the rational design and optimization of drug candidates. Here, we report the structures of native hMTHFS, a binary complex of hMTHFS with ADP, hMTHFS bound with the N5-iminium phosphate reaction intermediate, and an enzyme-product complex of hMTHFS. The N5-iminium phosphate captured for the first time in our crystal structure unravels a unique strategy used by hMTHFS for recognition of the substrate and provides structural basis for the regulation of enzyme activity. Binding of N10-substituted folate analogues places Y152 in the middle of the channel connecting ATP binding site with the substrate binding pocket, precluding the positioning of γ-phosphate for a nucleophilic attack. Using the structures of hMTHFS as a guide, we have probed the role of residues surrounding the active site in catalysis by mutagenesis. The ensemble of hMTHFS structures and the mutagenesis data yield a coherent picture of the MTHFS active site, determinants of substrate specificity, and new insights into the mechanism of inhibition of hMTHFS. [Cancer Res 2009;69(18):7294–301]
Immunogenicity of the Hu14.18-IL2 Immunocytokine Molecule in Adults With Melanoma and Children With Neuroblastoma
Authors: Hank Jacquelyn A. , Gan Jacek , Ryu Hyunji , Ostendorf Amy , Stauder Michael C. , Sternberg Adam , Albertini Mark , Lo Kin-Ming , Gillies Stephen D. , Eickhoff Jens , Sondel Paul M. 
Published: September 2009

Abstract
Purpose: Immunocytokine (IC) hu14.18-IL2 is a fusion protein of humanized antidisialoganglioside (GD2) antibody (hu14.18) and interleukin (IL)-2. Sixty-one melanoma and neuroblastoma patients received IC in phase I/Ib studies. Patient sera were examined in ELISA to determine if an anti-IC antibody response occurred during treatment.
Experimental Design: Serum was assayed for anti-idiotypic antibody (anti-id Ab) based on ability to bridge biotinylated hu14.18 to plate-bound hu14.18 and ability to inhibit binding of hu14.18 to GD2 antigen and/or murine anti-idiotypic antibody. ELISA was also used to detect antibodies to the Fc-IL2 end of hu14.18-IL2.
Results: Thirty-two patients (52%) developed an anti-idiotypic antibody response (absorbance, &gt;0.7) in the bridge ELISA. Twelve patients (20%) had an intermediate response, whereas 17 patients (28%) were negative (adsorbance, &lt;0.3). The development of antibody to hu14.18-IL2 detected in the bridge ELISA was not related to the dose of hu14.18-IL2. Twenty of 33 adult patients (61%) demonstrated an anti-idiotypic antibody response based on binding inhibition ELISA. The anti-idiotypic response was inversely correlated (P &lt; 0.002) with IC measured during the second course of treatment, indicating that development of anti-idiotypic antibodies interfered with detection of circulating hu14.18-IL2. All patients developed some inhibitory activity in the binding inhibition assay designed to detect antibodies to the Fc-IL2 region of the IC. There was a positive correlation between the peak serum level of IC in course 1 and the anti–Fc-IL2 response.
Conclusions: Patients treated with hu14.18-IL2 developed anti-idiotypic antibodies and anti Fc-IL2 antibodies. No association was seen between development of anti-IC antibodies and clinical toxicity. (Clin Cancer Res 2009;15(18):5923–30)
Induction of Bim Expression Contributes to the Antitumor Synergy Between Sorafenib and Mitogen-Activated Protein Kinase/Extracellular Signal-Regulated Kinase Kinase Inhibitor CI-1040 in Hepatocellular Carcinoma
Authors: Ou Da-Liang , Shen Ying-Chun , Liang Ja-Der , Liou Jun-Yang , Yu Sung-Liang , Fan Hsiang-Hsuan , Wang Da-Sheng , Lu Yen-Shen , Hsu Chiun , Cheng Ann-Lii 
Published: September 2009

Abstract
Purpose: Sorafenib has proved survival benefit for patients with advanced hepatocellular carcinoma (HCC). This study explored whether the efficacy of sorafenib can be improved by adding the mitogen-activated protein kinase/extracellular signal-regulated kinase (ERK) kinase (MEK) inhibitor CI-1040 to vertically block the Raf/MEK/ERK pathway.
Experimental Design: The growth inhibitory effects of sorafenib and CI-1040 were tested in HCC cell lines (Huh-7 and Hep3B) and human umbilical vascular endothelial cells (HUVEC). The potential synergistic growth inhibitory effects were measured by median effect analysis. Apoptosis was measured by flow cytometry. The effects on ERK phosphorylation and levels of apoptosis regulatory proteins were measured by Western blotting. The in vivo antitumor activity of sorafenib and CI-1040 were tested in xenograft HCC models.
Results: Combination of sorafenib and CI-1040 synergistically inhibited ERK phosphorylation and cell growth and induced apoptosis in both HCC cells and HUVECs. Increased expression of Bim protein, which correlated with the extent of ERK inhibition, was found in both HCC cells and HUVECs. Knockdown of Bim expression by small interfering RNA partially abrogated the synergistic proapoptotic effects of sorafenib and CI-1040. Combination therapy inhibited tumor growth significantly better than either single agent in the xenograft models.
Conclusion: The antitumor effects of sorafenib in HCC can be improved by vertical blockade of Raf/MEK/ERK signaling with CI-1040. (Clin Cancer Res 2009;15(18):5820–8)
C-Raf Is Associated with Disease Progression and Cell Proliferation in a Subset of Melanomas
Authors: Jilaveanu Lucia B. , Zito Christopher R. , Aziz Saadia A. , Conrad Patricia J. , Schmitz John C. , Sznol Mario , Camp Robert L. , Rimm David L. , Kluger Harriet M. 
Published: September 2009

Abstract
Purpose: Raf-kinases include three major isoforms. Although the role of B-Raf in melanoma is well established, little is known about C-Raf. We studied effects of C-Raf knockdown in vitro and assessed expression of C-Raf in a large cohort of melanomas and nevi.
Experimental Design: Using specific siRNAs, we knocked down C-Raf expression, and determined the effect on viability, MAP extracellular signal-regulated kinase (ERK)/ERK kinase signaling, and apoptosis in seven melanoma cell lines. We determined the IC50 of the C-Raf inhibitors sorafenib and GW5074, and studied the effects of GW5074 on cell signaling. Using an automated method to measure in situ protein expression, we quantified C-Raf expression in 263 nevi and 523 melanomas.
Results: C-Raf was knocked down in three cell lines with detectable phospho-C-Raf, resulting in decreased viability in two of the three (YULAC and YUROB). This resulted in decreased Bcl-2 expression and phospho-Bad cleavage, without affecting phospho-MEK and phospho-ERK. Sensitivity to sorafenib and GW5074 varied. GW5074 inhibited mitogen-activated protein kinase signaling without Bcl-2 and phospho-Bad down-regulation. C-Raf was highly expressed in melanomas compared with nevi (P &lt; 0.0001), and no nevi had high C-Raf expression. C-Raf expression was higher in metastatic than primary specimens (P = 0.0225).
Conclusions: C-Raf siRNA knock-down results in decreased viability of YULAC (B-RafV600K) and YUROB (B-RafWT) melanoma cells, likely mediated by Bcl-2 inhibition rather than mitogen-activated protein kinase inhibition. Cotargeting C-Raf and parallel pathways might be an effective therapeutic approach for melanoma. C-Raf expression is up-regulated in a subset of melanomas but not in nevi, suggesting that it might be a valuable diagnostic marker and therapeutic target. (Clin Cancer Res 2009;15(18):5704–13)
Putative Tumor-Suppressive Function of Krüppel-Like Factor 4 in Primary Lung Carcinoma
Authors: Hu Wenxian , Hofstetter Wayne L. , Li Hong , Zhou Yanbin , He Yong , Pataer Abujiang , Wang Li , Xie Keping , Swisher Stephen G. , Fang Bingliang 
Published: September 2009

Abstract
Purpose: Krüppel-like factor 4 (KLF4) is a zinc-finger protein that plays important roles in stem cells and the development of gastric cancers. However, the role of KLF4 in primary lung cancer is unknown. The purpose of this study is to determine possible roles of KLF4 in lung cancer.
Experimental Design: The KLF4 expression in primary lung cancer tissues and case-matched normal lung tissues were determined by protein and mRNA analyses. The effects of KLF4 on cell proliferation, clonogenic formation, and cell cycle progression were determined in cultured lung cancer cells or bronchial epithelial cells after enforced KLF4 overexpression or small interfering RNA knockdown. The in vivo antitumor activity of KLF4 was evaluated by using stably transfected lung cancer cells and by adenovector-mediated gene delivery. The effect of KLF4 in regulating p21 and cyclin D1 was also evaluated.
Results: KLF4 protein and mRNA levels were dramatically decreased in most primary lung tumors compared with in case-matched normal lung tissues. Enforced expression of KLF4 resulted in marked inhibition of cell growth and clonogenic formation. The tumor-suppressive effect of KLF4 was associated with its role in up-regulating p21 and down-regulating cyclin D1, leading to cell cycle arrest at the G1-S checkpoint. Knockdown of KLF4 promoted cell growth in immortalized human bronchial epithelial cells. The enforced expression of KLF4 gene to lung cancer cells by ex vivo transfection or adenovector-mediated gene transfer suppressed tumor growth in vivo.
Conclusions: Our results suggest that KLF4 plays an important role in suppressing the growth of lung carcinoma. (Clin Cancer Res 2009;15(18):5688–95)
Decreased Poly(ADP-Ribosyl)ation of CTCF, a Transcription Factor, Is Associated with Breast Cancer Phenotype and Cell Proliferation
Authors: Docquier France , Kita Georgia-Xanthi , Farrar Dawn , Jat Parmjit , O'Hare Michael , Chernukhin Igor , Gretton Svetlana , Mandal Adhip , Alldridge Louise , Klenova Elena 
Published: September 2009

Abstract
Purpose: There is compelling evidence of a relationship between poly(ADP-ribosyl)ation and tumorigenesis; however, much less is known about the role of specific targets of poly(ADP-ribosyl)ation in tumor development. Two forms of the multifunctional transcription factor, CTCF, were previously identified: a 130-kDa protein (CTCF-130), characteristic for cell lines, and a 180-kDa protein (CTCF-180), modified by poly(ADP-ribosyl)ation. This study was aimed to investigate differential poly(ADP-ribosyl)ation of CTCF in normal and tumor breast tissues.
Experimental Design: Western blot analysis, mass spectrometry, and immunohistochemical and immunofluorescent stainings were used to characterize CTCF-130 and CTCF-180 in breast cell lines, primary cultures, and normal and tumor breast tissues. The immunoreactivity score was used for CTCF-130 quantification in tissues.
Results: We discovered that only CTCF-180 is detected in the normal breast tissues, whereas both CTCF-130 and CTCF-180 are present in breast tumors. Using an antibody specific for CTCF-130, we observed that 87.7% of breast tumors were positive for CTCF-130. A negative correlation existed between the levels of CTCF-130, tumor stage, and tumor size. Significantly, a transition from CTCF-180 to CTCF-130 was discovered in primary cultures generated from normal breast tissues, indicating a link between CTCF-130 and proliferation. Conversely, the appearance of CTCF-180 was observed following growth arrest in breast cell lines.
Conclusions: Collectively, our data suggest that the loss of CTCF poly(ADP-ribosyl)ation is associated with cell proliferation and breast tumor development. We propose the use of CTCF-130 as a marker for tumor breast cells and lower levels of CTCF-130 as an indicator of unfavorable prognosis. (Clin Cancer Res 2009;15(18):5762–71)
High-Dose Zoledronic Acid Impacts Bone Remodeling with Effects on Osteoblastic Lineage and Bone Mechanical Properties
Authors: Pozzi Samantha , Vallet Sonia , Mukherjee Siddhartha , Cirstea Diana , Vaghela Nileshwari , Santo Loredana , Rosen Eyal , Ikeda Hiroshi , Okawa Yutaka , Kiziltepe Tanyel , Schoonmaker Jesse , Xie Wanling , Hideshima Teru , Weller Edie , Bouxsein Mary L. , Munshi Nikhil C. , Anderson Kenneth C. , Raje Noopur 
Published: September 2009

Abstract
Purpose: The increasing incidence of osteonecrosis of the jaw and its possible association with high cumulative doses of bisphosphonate led us to study the effects of high doses of zoledronic acid (ZA) on bone remodeling.
Experimental Design: Five-week-old C57BL6 mice were treated with saline or ZA weekly for 3 weeks at increasing doses (0.05-1 mg/Kg). Effects of ZA on bone remodeling were studied using standard assays.
Results: We observed an increase in bone mineral density and content in treated animals at doses of 0.05 mg/Kg, which was not further enhanced at higher doses of ZA. Trabecular bone volume at the proximal tibia and the distal femur assessed by histomorphometry and microCT, respectively, increased significantly in ZA-treated groups. There was however no difference between 0.5 and 1 mg/kg, suggesting a ceiling effect for ZA. ZA led to decreased numbers of osteoclasts and osteoblasts per bone perimeter that paralleled a significant reduction of serum levels of TRAC5b and osteocalcin in vivo. Effects on osteoblasts were confirmed in in vitro assays. Mechanical testing of the femur showed increased brittleness in ZA-treated mice.
Conclusions: High doses of ZA inhibit both osteoclast and osteoblasts function and bone remodeling in vivo interfering with bone mechanical properties. No dose response was noted beyond 0.5 mg/kg suggesting that lower doses of ZA may be adequate in inhibiting bone resorption. Our data may help inform future studies of ZA use with respect to alternate and lower doses in the treatment of patients with cancer bone disease. (Clin Cancer Res 2009;15(18):5829–39)
Identification of the Transcription Factor Single-Minded Homologue 2 as a Potential Biomarker and Immunotherapy Target in Prostate Cancer
Authors: Arredouani Mohamed S. , Lu Bin , Bhasin Manoj , Eljanne Miriam , Yue Wen , Mosquera Juan-Miguel , Bubley Glenn J. , Li Vivian , Rubin Mark A. , Libermann Towia A. , Sanda Martin G. 
Published: September 2009

Abstract
Purpose: Identification of novel biomarkers and immunotherapy targets for prostate cancer (PCa) is crucial to better diagnosis and therapy. We sought to identify novel PCa tumor-associated antigens (TAA) that are expressed in PCa, absent in nonprostate human tissue, and immunogenic for immune responses restricted by human HLA.
Experimental Design and Results: Using microarray analysis of normal and cancerous human prostate tissues, we identified 1,063 genes overexpressed in PCa. After validating 195 transcripts in publicly available array data sets, we interrogated expression of these TAAs in normal human tissues to identify genes that are not expressed at detectable levels in normal, nonprostate adult human tissue. We identified 23 PCa TAA candidates. Real-time PCR confirmed that 15 of these genes were overexpressed in PCa (P&lt; 0.05 for each). The most frequently overexpressed gene, single-minded homologue 2 (SIM2), was selected for further evaluation as a potential target for immunotherapy. ELISA assay revealed that a fraction of PCa patients exhibited immune responsiveness to SIM2 as evidenced by the presence of autoantibodies to SIM2 in their sera. We next showed binding of putative HLA-A2.1–restricted SIM2 epitopes to human A2.1, and immunization of transgenic HLA-A2.1 mice showed induction of SIM2-specific CTL responses in vivo.
Conclusions: Our findings that SIM2 is selectively expressed in PCa, that human HLA-A2.1–restricted SIM2 epitopes induce specific T cells in vivo, and that anti-SIM2 antibodies are detectable in PCa patients' sera implicate SIM2 as a PCa-associated antigen that is a suitable potential target for PCa immunotherapy. (Clin Cancer Res 2009;15(18):5794–802)