bluuebunny/crossref_metadata_2025 huggingface dataset:
Differential regulation of the renal sodium-phosphate cotransporters NaPi-IIa, NaPi-IIc, and PiT-2 in dietary potassium deficiency
Authors: Breusegem Sophia Y. , Takahashi Hideaki , Giral-Arnal Hector , Wang Xiaoxin , Jiang Tao , Verlander Jill W. , Wilson Paul , Miyazaki-Anzai Shinobu , Sutherland Eileen , Caldas Yupanqui , Blaine Judith T. , Segawa Hiroko , Miyamoto Ken-ichi , Barry Nicholas P. , Levi Moshe
Published: June 2009

Dietary potassium (K) deficiency is accompanied by phosphaturia and decreased renal brush border membrane (BBM) vesicle sodium (Na)-dependent phosphate (Pi) transport activity. Our laboratory previously showed that K deficiency in rats leads to increased abundance in the proximal tubule BBM of the apical Na-Pi cotransporter NaPi-IIa, but that the activity, diffusion, and clustering of NaPi-IIa could be modulated by the altered lipid composition of the K-deficient BBM (Zajicek HK, Wang H, Puttaparthi K, Halaihel N, Markovich D, Shayman J, Beliveau R, Wilson P, Rogers T, Levi M. Kidney Int 60: 694–704, 2001; Inoue M, Digman MA, Cheng M, Breusegem SY, Halaihel N, Sorribas V, Mantulin WW, Gratton E, Barry NP, Levi M. J Biol Chem 279: 49160–49171, 2004). Here we investigated the role of the renal Na-Pi cotransporters NaPi-IIc and PiT-2 in K deficiency. Using Western blotting, immunofluorescence, and quantitative real-time PCR, we found that, in rats and in mice, K deficiency is associated with a dramatic decrease in the NaPi-IIc protein abundance in proximal tubular BBM and in NaPi-IIc mRNA. In addition, we documented the presence of a third Na-coupled Pi transporter in the renal BBM, PiT-2, whose abundance is also decreased by dietary K deficiency in rats and in mice. Finally, electron microscopy showed subcellular redistribution of NaPi-IIc in K deficiency: in control rats, NaPi-IIc immunolabel was primarily in BBM microvilli, whereas, in K-deficient rats, NaPi-IIc BBM label was reduced, and immunolabel was prevalent in cytoplasmic vesicles. In summary, our results demonstrate that decreases in BBM abundance of the phosphate transporter NaPi-IIc and also PiT-2 might contribute to the phosphaturia of dietary K deficiency, and that the three renal BBM phosphate transporters characterized so far can be differentially regulated by dietary perturbations.
Modulation of the allergic asthma transcriptome following resiquimod treatment
Authors: Camateros Pierre , Kanagaratham Cynthia , Henri Jennifer , Sladek Rob , Hudson Thomas J. , Radzioch Danuta
Published: June 2009

Resiquimod is a compound belonging to the imidazoquinoline family of compounds known to signal through Toll-like receptor 7. Resiquimod treatment has been demonstrated to inhibit the development of allergen induced asthma in experimental models. The aim of the present study was to elucidate the molecular processes that were altered following resiquimod treatment and allergen challenge in a mouse model of allergic asthma. Employing microarray analysis, we have characterized the “asthmatic” transcriptome of the lungs of A/J and C57BL/6 mice and determined that it includes genes involved in the control of cell cycle progression, the complement and coagulation cascades, and chemokine signaling. Our results demonstrated that resiquimod treatment resulted in the normalization of the expression of genes involved with airway remodeling, and generally, chemokine signaling. Resiquimod treatment also altered the expression of cell adhesion molecules, and molecules involved in natural killer (NK) cell-mediated cytotoxicity. Furthermore, we have demonstrated that systemic resiquimod administration resulted in the recruitment of NK cells to the lungs and livers of the mice, although no causal relationship between NK cell recruitment and treatment efficacy was found. Overall, our findings identified several genes, important in the development of asthma pathology, that were normalized following resiquimod treatment, thus improving our understanding of the molecular consequences of resiquimod treatment in the lung milieu. The recruitment of NK cells to the lungs may also have application in the treatment of virally induced asthma exacerbations.
Protein families reflect the metabolic diversity of organisms and provide support for functional prediction
Authors: Nahum Laila A. , Goswami Sulip , Serres Margrethe H.
Published: June 2009

Comparative genomics has shown that protein families vary significantly within and across organisms in both number and functional composition. In the present work, we tested how the diversity at the family level reflects biological differences among organisms and contributes to their unique characteristics. For this purpose, we collected sequence-similar proteins of three selected families from model bacteria: Escherichia coli, Bacillus subtilis, and Pseudomonas aeruginosa. Protein relationships were identified using a phylogenomic approach to connect the functional diversity of enzymes to the metabolic capabilities of these organisms. All protein families studied have distinct functional compositions across the selected bacteria as supported by our Bayesian analysis. Some conserved functional features among family members included a shared reaction mechanism, cofactor usage, and/or ligand specificity. Many observations of the presence/absence of protein functions matched current knowledge of the physiology and biochemistry of the bacteria. In some cases, new functional predictions were made to family members previously uncharacterized. We believe that genome comparisons at the protein family level would also be useful in predicting metabolic diversity for organisms that are relatively unknown or currently uncultured in the laboratory.
Adipokines in Nonalcoholic Steatohepatitis: From Pathogenesis to Implications in Diagnosis and Therapy
Authors: Tsochatzis Emmanuel A. , Papatheodoridis George V. , Archimandritis Athanasios J.
Published: June 2009

Nonalcoholic fatty liver disease (NAFLD) is the hepatic manifestation of the metabolic syndrome and can vary from benign steatosis to end-stage liver disease. The pathogenesis of non-alcoholic steatohepatitis (NASH) is currently thought to involve a multiple-hit process with the first hit being the accumulation of liver fat which is followed by the development of necroinflammation and fibrosis. There is mounting evidence that cytokines secreted from adipose tissue, namely, adipokines, are implicated in the pathogenesis and progression of NAFLD. In the current review, we explore the role of these adipokines, particularly leptin, adiponectin, resistin, tumor necrosis factor-a, and interleukin-6 in NASH, as elucidated in experimental models and clinical practice. We also comment on their potential use as noninvasive markers for differentiating simple fatty liver from NASH as well as on their potential future therapeutic role in patients with NASH.
Comparative Analysis of the Membrane Proteome of Closely Related Metastatic and Nonmetastatic Tumor Cells
Authors: Roesli Christoph , Borgia Beatrice , Schliemann Christoph , Gunthert Maja , Wunderli-Allenspach Heidi , Giavazzi Raffaella , Neri Dario
Published: June 2009

The identification of proteins that are preferentially expressed on the membrane of metastatic tumor cells is of fundamental importance in cancer research. Here, we report the systematic comparison of the membrane proteome of two closely related murine teratocarcinoma cell lines (F9B9 and F9DR), of which only one (F9DR) is capable of forming liver metastases in vivo. The proteomic methodology used in this study featured the surface protein biotinylation on tumor cells followed by protein purification on streptavidin resin and relative quantification of corresponding tryptic peptides by mass spectrometric procedures. The study allowed the identification of 998 proteins and the determination of their relative abundance. Proteins previously known to be associated with metastatic spread were found to be either up-regulated (e.g., synaptojanin-2) or down-regulated (e.g., Ceacam1) in F9DR cells. A dramatic increase in abundance at the cell membrane was observed for a broad variety of proteins (e.g., high-mobility group protein B1), which were mainly thought to reside in intracellular compartments, a finding that was confirmed using confocal laser scanning microscopy and immunochemical analysis of cell cultures. Furthermore, we showed by microautoradiographic analysis that certain target proteins can readily be reached by intravenously administered radiolabeled antibodies. Finally, we showed that the most promising antigens for antibody-based pharmacodelivery approaches are strongly and selectively expressed on the surface of tumor cells in three different syngeneic mouse models of liver metastases. Taken together, our results indicate that the expression of intracellular proteins on the membrane of metastatic cells is a feature much more common than previously expected. [Cancer Res 2009;69(13):5406–14]
Efficacy of Levo-1-Methyl Tryptophan and Dextro-1-Methyl Tryptophan in Reversing Indoleamine-2,3-Dioxygenase–Mediated Arrest of T-Cell Proliferation in Human Epithelial Ovarian Cancer
Authors: Qian Feng , Villella Jeannine , Wallace Paul K. , Mhawech-Fauceglia Paulette , Tario Joseph D. , Andrews Christopher , Matsuzaki Junko , Valmori Danila , Ayyoub Maha , Frederick Peter J. , Beck Amy , Liao Jianqun , Cheney Richard , Moysich Kirsten , Lele Shashikant , Shrikant Protul , Old Lloyd J. , Odunsi Kunle
Published: June 2009

It has been reported that levo-1-methyl tryptophan (L-1MT) can block indoleamine-2,3-dioxygenase (IDO) expressed by human dendritic cells (DC), whereas dextro-1-methyl tryptophan (D-1MT) is inefficient. However, whether L-1MT or D-1MT can efficiently reverse IDO-induced arrest of human T-cell proliferation has not been clarified. Here, we show a marked immunosuppressive effect of IDO derived from INDO-transfected 293 cell, IDO+ ovarian cancer cells, and monocyte-derived DCs on CD4+ Th1 cells, CD8+ T cells, and natural killer cells derived from peripheral blood, ascites, and tumors of ovarian cancer patients. We found that, whereas L-1MT and D/L-1MT can restore proliferation of tumor-derived and peripheral blood T-cell subsets, D-1MT does not effectively restore IDO-induced arrest of T-cell proliferation. Although D-1MT inhibited kynurenine production at high concentrations, L-1MT was more effective in abrogating kynurenine generation and tryptophan depletion, whereas tryptophan was completely depleted by IDO even in the presence of high amounts of D-1MT. Together, the results indicate that, whereas the generation of tryptophan metabolites (kynurenines) by IDO is important in mediating suppression of T-cell proliferation, the degree to which tryptophan depletion is restored by 1MT is also critical in overcoming IDO-induced arrest of T-cell proliferation. [Cancer Res 2009;69(13):5498–504]
Donor CD4 T Cells Are Critical in Allogeneic Stem Cell Transplantation against Murine Solid Tumor
Authors: Kamiryo Yoriyuki , Eto Masatoshi , Yamada Hisakata , Yajima Toshiki , Harano Masahiko , Takeuchi Ario , Tatsugami Katsunori , Hamaguchi Masumitsu , Naito Seiji , Yoshikai Yasunobu
Published: June 2009

Nonmyeloablative allogeneic stem cell transplantation (SCT) has been used for various malignancies, although detailed mechanisms of antitumor effects remain unclear. We showed that a nonmyeloablative allogeneic SCT regimen, which consists of mixed chimerism induced by an injection of donor spleen and bone marrow cells followed by cyclophosphamide treatment and a donor lymphocyte infusion (DLI), exerted antitumor effects on established murine bladder tumor, MBT-2. An expansion of donor CD4 T cells accompanied by transient but vigorous IFN-γ production was detected shortly after DLI. In vivo neutralization of IFN-γ or depletion of CD4 T cells from DLI abolished the antitumor effects, indicating an indispensable role of donor CD4 T cells producing IFN-γ. Donor as well as host CD8 T cells accumulated in the tumor region with time. Importantly, depletion of CD8 T cells from DLI did not reverse the suppression of tumor growth, indicating that CD4 T cells play a more essential role in mediating early antitumor effects. Furthermore, tumor-specific response of host CD8 T cells was suggested. These results not only provide the first evidence of nonmyeloablative allogeneic SCT for the treatment of bladder tumor but also elucidate detailed mechanisms of antitumor effects provoked by DLI. [Cancer Res 2009;69(12):5151–8]
Regulation of DNA Polymerase β by the LMP1 Oncoprotein of EBV through the Nuclear Factor-κB Pathway
Authors: Faumont Nathalie , Le Clorennec Christophe , Teira Pierre , Goormachtigh Gauthier , Coll Jean , Canitrot Yvan , Cazaux Christophe , Hoffmann Jean-Sébastien , Brousset Pierre , Delsol Georges , Feuillard Jean , Meggetto Fabienne
Published: June 2009

The repair DNA polymerase β (Polβ), when overexpressed, plays a critical role in generating genetic instability via its interference with the genomic replication program. Up-regulation of Polβ has been reported in many tumor types that exhibit genetic aberrations, including EBV-related B-cell lymphomas. However, the mechanisms responsible for its overexpression have never been examined. Here, we report that both expression and activity of Polβ, in EBV-immortalized B cells, are induced by several natural genetic variants of LMP1, an oncoprotein associated with the vast majority of EBV-related tumors. Conversely, we found that the expression of Polβ decreased when LMP1 signaling was down-regulated by a dominant negative of LMP1 or an inhibitor of the nuclear factor-κB (NF-κB) pathway, the main transduction pathway activated by LMP1, strongly supporting a role of NF-κB in the LMP1-mediated Polβ regulation. Using electrophoretic mobility shift assay experiments from several EBV-immortalized B-cell nuclear extracts, we identified an LMP1-dependent p50/c-Rel heterodimer on a proximal κB binding site (−211 to −199nt) of the Polβ promoter. This result was correlated with a specific Polβ κB transcriptional activity. Taken together, our data enlighten a new mechanism responsible for Polβ overexpression in EBV-infected cells, mediated by LMP1 and dependent on NF-κB activation. [Cancer Res 2009;69(12):5177–85]
Estrogen-Related Receptor α Expression and Function Is Associated with the Transcriptional Coregulator AIB1 in Breast Carcinoma
Authors: Heck Stefanie , Rom Joachim , Thewes Verena , Becker Natalia , Blume Beatrix , Sinn Hans Peter , Deuschle Ulrich , Sohn Christof , Schneeweiss Andreas , Lichter Peter
Published: June 2009

The significance of the estrogen-related receptor α (ERRα) as prognostic marker for poor clinical outcome in breast carcinoma has recently been reported. Transcriptional activity of nuclear receptors such as ERRα depends on coregulatory proteins. Thus, we compared the expression of different receptors, coregulators, and target genes on RNA and protein level in identical primary breast tumor samples (n = 48). We found a positive correlation between the transcripts of ERRα and AIB1 (amplified in breast cancer-1), a coactivator overexpressed in breast cancers and associated with resistance to antihormone treatment. These data were confirmed on protein level, studying an independent patient collection (n = 257). Expression of the estrogen-regulated gene pS2 was associated with ERRα only in tumors, where estrogen receptor (ERα) expression was low or absent. In ERα high expressing tumors, no correlation of ERRα and pS2 was observed. AIB1 interacts directly with ERRα as shown by fluorescence-resonance energy transfer, mammalian two-hybrid, and coimmunoprecipitation assays with endogenous proteins. It enhances ERRα transcriptional activity in ERα-negative breast cancer cell lines as shown in functional reporter gene assays. Blocking ERRα with an inverse agonist abolished interaction and coactivation by AIB1. Recruitment of both proteins to ERRα target gene promoters further supports the significance of their interaction. Our findings identify AIB1 as functionally relevant cofactor for ERRα in breast carcinoma. ERRα/AIB1 complexes may control estradiol-regulated genes in a hormone-independent manner. Accordingly, ERRα might be a rewarding target for treatment of endocrine-resistant tumors. [Cancer Res 2009;69(12):5186–93]
The Activated Notch1 Signal Pathway Is Associated with Gastric Cancer Progression through Cyclooxygenase-2
Authors: Yeh Tien-Shun , Wu Chew-Wun , Hsu Kai-Wen , Liao Wan-Jung , Yang Min-Chieh , Li Anna Fen-Yau , Wang An-Ming , Kuo Min-Liang , Chi Chin-Wen
Published: June 2009

Gastric carcinoma is one of the most common cancers and lethal malignancies worldwide. Thus far, the regulatory mechanisms of its aggressiveness are still poorly understood. To understand the pathogenesis and to develop new therapeutic strategies, it is essential to dissect the molecular mechanisms that regulate progression of gastric cancer. Herein, we sought to address whether Notch1 signal pathway is involved in the control of progression in gastric cancer. We found that expression of Notch ligand Jagged1 was correlated with aggressiveness of human gastric cancer. Patients with Jagged1 expression in gastric cancer tissues had a poor survival rate compared with those without Jagged1 expression. The Notch1 receptor intracellular domain (N1IC), the activated form of Notch1 receptor, promoted the colony-forming ability and xenografted tumor growth of human stomach adenocarcinoma SC-M1 cells. Migration and invasion abilities of SC-M1 cells were enhanced by N1IC. Furthermore, N1IC and C promoter–binding factor 1 (CBF1) bound to cyclooxygenase-2 (COX-2) promoter and elevated COX-2 expression in SC-M1 cells through a CBF1-dependent manner. The colony-forming, migration, and invasion abilities enhanced by N1IC were suppressed in SC-M1 cells after treatment with the COX-2 inhibitor NS-398 or knockdown of COX-2. These cellular processes inhibited by Notch1 knockdown were restored by prostaglandin E2 or exogenous COX-2. Taken together, these results suggest that activation of Notch1 signal pathway promotes progression of gastric cancer, at least in part through COX-2. [Cancer Res 2009;69(12):5039–48]
TOB1 Is Regulated by EGF-Dependent HER2 and EGFR Signaling, Is Highly Phosphorylated, and Indicates Poor Prognosis in Node-Negative Breast Cancer
Authors: Helms Mike W. , Kemming Dirk , Contag Christopher H. , Pospisil Heike , Bartkowiak Kai , Wang Alice , Chang Sheng-Yung , Buerger Horst , Brandt Burkhard H.
Published: June 2009

Clinical and animal studies have shown that coexpression of the receptor tyrosine kinases HER2 and epidermal growth factor (EGF) receptor (EGFR) indicates a highly metastatic phenotype of breast cancer. In a cellular model of this phenotype using differential gene expression analysis, we identified TOB1 to be up-regulated depending on EGF stimulation and transduction through phosphorylation of HER2 tyrosine 1248. mRNA expression analysis of breast cancers from a cohort of node-negative patients showed significantly shortened distant metastasis-free survival for patients with high TOB1 expression. In subsequent tissue microarray studies of 725 clinical samples, high HER2 and EGF protein levels were significantly correlated with TOB1 expression in breast cancer, whereas EGFR and EGF levels correlated with TOB1 phosphorylation. We did not observe a correlation between TOB1 expression and cyclin D1, which was previously suggested to mediate the antiproliferative effect of unphosphorylated TOB1. A positive correlation of TOB1 phosphorylation status with proliferation marker Ki67 suggests that elevated TOB1 phosphorylation might abrogate the antiproliferative effect of TOB1 in breast cancer. This suggests a new regulatory role for TOB1 in cancer progression with particular significance in HER2- and/or EGFR-positive breast cancers. [Cancer Res 2009;69(12):5049–56]
Effects of Vandetanib on Lung Adenocarcinoma Cells Harboring Epidermal Growth Factor Receptor T790M Mutation In vivo
Authors: Ichihara Eiki , Ohashi Kadoaki , Takigawa Nagio , Osawa Masahiro , Ogino Atsuko , Tanimoto Mitsune , Kiura Katsuyuki
Published: June 2009

Vandetanib is a novel multitarget tyrosine kinase inhibitor (TKI) that inhibits vascular endothelial growth factor receptor-2 (VEGFR-2), with additional inhibition of epidermal growth factor receptor (EGFR) and rearranged during transfection receptor signaling, which has shown promising results in clinical trials for advanced non–small cell lung cancer. However, the mechanisms of acquired resistance to vandetanib remain unclear. Therefore, we established in vitro vandetanib-resistant PC-9/VanR cells from PC-9, a vandetanib-sensitive lung adenocarcinoma cell line, by chronic exposure to this agent. PC-9/VanR cells were 50-fold more resistant to vandetanib than PC-9 cells in vitro. Compared with PC-9 cells, PC-9/VanR cells showed emergence of an EGFR T790M mutation, moderately elevated MET amplification, and similar VEGFR-2 inhibition by vandetanib. Note that phospho-MET in PC-9/VanR was suppressed following EGFR inhibition by an irreversible EGFR-TKI, indicating that MET signaling of PC-9/VanR was dependent on EGFR signaling and that MET amplification was not the primary mechanism of resistance to vandetanib. In contrast to the in vitro experiment, vandetanib effectively inhibited the growth of PC-9/VanR tumors in an in vivo xenograft model through the antiangiogenesis effects of VEGFR-2 inhibition. In conclusion, the multitarget TKI vandetanib induced or selected for the EGFR T790M mutation as observed previously with highly selective EGFR-TKIs. However, vandetanib retained significant efficacy in vivo against xenografts harboring the T790M mutation, providing a strong scientific rationale for investigating vandetanib in clinical settings where acquired resistance through emergence of EGFR T790M mutations limits the effectiveness of highly selective EGFR-TKIs. [Cancer Res 2009;69(12):5091–8]
The mRNA-Destabilizing Protein Tristetraprolin Is Suppressed in Many Cancers, Altering Tumorigenic Phenotypes and Patient Prognosis
Authors: Brennan Sarah E. , Kuwano Yuki , Alkharouf Nadim , Blackshear Perry J. , Gorospe Myriam , Wilson Gerald M.
Published: June 2009

AU-rich element-binding proteins (ARE-BP) regulate the stability and/or translational efficiency of mRNAs containing cognate binding sites. Many targeted transcripts encode factors that control processes such as cell division, apoptosis, and angiogenesis, suggesting that dysregulated ARE-BP expression could dramatically influence oncogenic phenotypes. Using several approaches, we evaluated the expression of four well-characterized ARE-BPs across a variety of human neoplastic syndromes. AUF1, TIA-1, and HuR mRNAs were not systematically dysregulated in cancers; however, tristetraprolin mRNA levels were significantly decreased across many tumor types, including advanced cancers of the breast and prostate. Restoring tristetraprolin expression in an aggressive tumor cell line suppressed three key tumorgenic phenotypes: cell proliferation, resistance to proapoptotic stimuli, and expression of vascular endothelial growth factor mRNA. However, the cellular consequences of tristetraprolin expression varied across different cell models. Analyses of gene array data sets revealed that suppression of tristetraprolin expression is a negative prognostic indicator in breast cancer, because patients with low tumor tristetraprolin mRNA levels were more likely to present increased pathologic tumor grade, vascular endothelial growth factor expression, and mortality from recurrent disease. Collectively, these data establish that tristetraprolin expression is frequently suppressed in human cancers, which in turn can alter tumorigenic phenotypes that influence patient outcomes. [Cancer Res 2009;69(12):5168–76]
Akt1 and Akt2 Play Distinct Roles in the Initiation and Metastatic Phases of Mammary Tumor Progression
Authors: Dillon Rachelle L. , Marcotte Richard , Hennessy Bryan T. , Woodgett James R. , Mills Gordon B. , Muller William J.
Published: June 2009

The phosphatidylinositol 3-kinase (PI3K)/Akt survival pathway is often dysregulated in cancer. Our previous studies have shown that coexpression of activated Akt1 with activated ErbB2 or polyoma virus middle T antigen uncoupled from the PI3K pathway (PyVmT Y315/322F) accelerates mammary tumor development but cannot rescue the metastatic phenotype associated with these models. Here, we report the generation of transgenic mice expressing activated Akt2 in the mammary epithelium. Like the mouse mammary tumor virus-Akt1 strain, mammary-specific expression of Akt2 delayed mammary gland involution. However, in contrast to Akt1, coexpression of Akt2 with activated ErbB2 or PyVmT Y315/322F in the mammary glands of transgenic mice did not affect the latency of tumor development. Strikingly, Akt2 coexpresssion markedly increased the incidence of pulmonary metastases in both tumor models, demonstrating a unique role in tumor progression. Together, these observations argue that these highly conserved kinases have distinct biological and biochemical outputs that play opposing roles in mammary tumor induction and metastasis. [Cancer Res 2009;69(12):5057–64]
HOXA13 Promotes Cancer Cell Growth and Predicts Poor Survival of Patients with Esophageal Squamous Cell Carcinoma
Authors: Gu Zhen-Dong , Shen Lu-Yan , Wang Hua , Chen Xiao-Mei , Li Yong , Ning Tao , Chen Ke-Neng
Published: June 2009

Homeobox genes are known to be classic examples of the intimate relationship between embryogenesis and tumorigenesis. Here, we investigated whether inhibition of HOXA13, a member of the homeobox genes, was sufficient to affect the proliferation of esophageal cancer cells in vitro and in vivo, and studied the association between HOXA13 expression and survival of patients with esophageal squamous cell carcinoma (ESCC). HOXA13 expression was permanently knocked down using an RNA interference technique, and cell strain with stable knockdown of HOXA13 protein was established. Colony formation assay showed that the number of colonies in HOXA13 protein–deficient cells was significantly less than that of control cells (P < 0.01). Tumor growth in nude mice showed that the weight and volume of tumors from the HOXA13 knockdown cells was significantly less than that from the control cells (P < 0.01). Then, HOXA13 expression in ESCC specimens and paired noncancerous mucosa was detected by immunohistochemistry, and overexpression of HOXA13 was found to be more pronounced in ESCCs than paired noncancerous mucosa (P < 0.05). Furthermore, the association of HOXA13 expression and disease-free survival time was analyzed in 155 ESCC cases. The median survival time of patients expressing HOXA13 was significantly shorter than HOXA13-negative patients (P = 0.0006). Multivariate analysis indicated that tumor-node-metastasis (TNM) stage and HOXA13 expression were independent predictors of disease-free survival time of patients with ESCC. Our results showed that HOXA13 expression enhanced tumor growth in vitro and in vivo, and was a negative independent predictor of disease-free survival of patients with ESCC. [Cancer Res 2009;69(12):4969–73]
Genetic Variants on Chromosome 15q25 Associated with Lung Cancer Risk in Chinese Populations
Authors: Wu Chen , Hu Zhibin , Yu Dianke , Huang Liming , Jin Guangfu , Liang Jie , Guo Huan , Tan Wen , Zhang Mingfeng , Qian Ji , Lu Daru , Wu Tangchun , Lin Dongxin , Shen Hongbing
Published: June 2009

Recent three genome-wide association studies have mapped a lung cancer susceptibility locus to chromosome 15q25 in Caucasians. However, the reported risk single nucleotide polymorphisms (SNPs) are extremely rare in Asians, arguing against any of these being causative variants. This study sought to identify other variants on 15q25 associated with lung cancer susceptibility in Chinese. Two-stage case-control studies were conducted in subjects derived from both Northern and Southern China. The first-stage, consisting of 576 cases and 576 controls, was to discover novel risk variants using a haplotype-tagging SNP approach, and these variants were then replicated in the second-stage, consisting of 2,989 cases and 2,880 controls. Associations were estimated by logistic regression models, and function of the variants was examined by biochemical assays. We found that the three risk SNPs reported in Caucasians were not associated with lung cancer risk in Chinese. However, we identified four novel SNPs (rs2036534C>T, rs667282C>T, rs12910984G>A, and rs6495309T>C) that were associated with significantly increased lung cancer risk and smoking behavior, which were all confirmed in the replication analyses [odds ratios (95% confidence intervals) in the dominant model: 1.39 (1.23–1.57; P = 2.3 × 10−7), 1.52 (1.35–1.71; P = 2.0 × 10−12), 1.44 (1.28–1.63; P = 2.7 × 10−9), and 1.43 (1.27–1.61; P = 2.6 × 10−9), respectively]. We characterized the rs6495309T>C change in the CHRNA3 promoter as a functional variant because it affected the Oct-1 binding ability, resulting in increased CHRNA3 expression. These results support 15q25 as a susceptibility region for lung cancer in Chinese but underscore the difference in genetic markers among different ethnic populations. [Cancer Res 2009;69(12):5065–72]
A Novel Type of p53 Pathway Dysfunction in Chronic Lymphocytic Leukemia Resulting from Two Interacting Single Nucleotide Polymorphisms within the p21 Gene
Authors: Johnson Gillian G. , Sherrington Paul D. , Carter Anthony , Lin Ke , Liloglou Triantafillos , Field John K. , Pettitt Andrew R.
Published: June 2009

The ATM-p53 pathway plays an important role in the biology of chronic lymphocytic leukemia (CLL). Its functional integrity can be probed by exposing CLL cells to ionizing radiation (IR) and measuring levels of p53 protein and one of its transcriptional targets, the cyclin-dependent kinase inhibitor p21. We have previously identified two abnormal p53/p21 response patterns associated with inactivating mutations of TP53 and ATM, respectively. Here, we describe a third abnormal response pattern characterized by failure of p21 protein accumulation despite a normal p53 protein response. This so-called "type C" response was detected in 10.6% of unselected patients and was associated with resistance of CLL cells to p53-dependent killing by IR, with the clinically more aggressive variant of CLL characterized by unmutated immunoglobulin heavy-chain genes and with a single nucleotide polymorphism at codon 31 of the p21 gene in which Ser is replaced by Arg. CLL samples with this allelic variant displayed impaired IR-induced up-regulation of total p21 mRNA and did not express the Arg-encoding transcript, except in those cases harboring an additional single nucleotide polymorphism (T instead of C) in the 3′-untranslated region of the same p21 allele. Our data provide new insight into the importance of p21 in CLL biology. [Cancer Res 2009;69(12):5210–17]
The Tumor Suppressor Gene Hypermethylated in Cancer 1 Is Transcriptionally Regulated by E2F1
Authors: Jenal Mathias , Trinh Emmanuelle , Britschgi Christian , Britschgi Adrian , Roh Vincent , Vorburger Stephan A. , Tobler Andreas , Leprince Dominique , Fey Martin F. , Helin Kristian , Tschan Mario P.
Published: June 2009

The Hypermethylated in Cancer 1 (HIC1) gene encodes a zinc finger transcriptional repressor that cooperates with p53 to suppress cancer development. We and others recently showed that HIC1 is a transcriptional target of p53. To identify additional transcriptional regulators of HIC1, we screened a set of transcription factors for regulation of a human HIC1 promoter reporter. We found that E2F1 strongly activates the full-length HIC1 promoter reporter. Promoter deletions and mutations identified two E2F responsive elements in the HIC1 core promoter region. Moreover, in vivo binding of E2F1 to the HIC1 promoter was shown by chromatin immunoprecipitation assays in human TIG3 fibroblasts expressing tamoxifen-activated E2F1. In agreement, activation of E2F1 in TIG3-E2F1 cells markedly increased HIC1 expression. Interestingly, expression of E2F1 in the p53−/− hepatocellular carcinoma cell line Hep3B led to an increase of endogenous HIC1 mRNA, although bisulfite genomic sequencing of the HIC1 promoter revealed that the region bearing the two E2F1 binding sites is hypermethylated. In addition, endogenous E2F1 induced by etoposide treatment bound to the HIC1 promoter. Moreover, inhibition of E2F1 strongly reduced the expression of etoposide-induced HIC1. In conclusion, we identified HIC1 as novel E2F1 transcriptional target in DNA damage responses. (Mol Cancer Res 2009;7(6):916–22)
Src Promotes Survival and Invasion of Lung Cancers with Epidermal Growth Factor Receptor Abnormalities and Is a Potential Candidate for Molecular-Targeted Therapy
Authors: Leung Elaine Lai-Han , Tam Issan Yee-San , Tin Vicky Pui-Chi , Chua Daniel Tsin-Tien , Sihoe Alan Dart-Loon , Cheng Lik-Cheung , Ho James Chung-Man , Chung Lap-Ping , Wong Maria Pik
Published: June 2009

Molecular-targeted therapy using tyrosine kinase inhibitors against epidermal growth factor receptor (EGFR) is an effective therapy for non–small cell lung cancer that harbor EGFR mutations. This study aimed to investigate the role of Src, a close EGFR associator, as a drug target in NSCLC cells with different EGFR genomic statuses. Src inhibition was achieved using 4-(4′-Phenoxyanilino)-6,7-dimethoxyquinazolinee (SKI-1) and the specificity of action was verified by RNA interference. The results showed that SKI-1 induced significant apoptosis in a dose-dependent manner in cancer cells with high basal Src activation. Activation of FAK and p130Cas was involved in Src-mediated invasion in SKI-1–sensitive cells. SKI-1 inhibited phosphorylation of EGFR as well as EGFR downstream effectors, such as signal transducers and activators of transcription 3/5, extracellular signal-regulated kinase 1/2 and AKT in the mutant cells but not the wild-type cells. This inhibition profile of EGFR implicates that induction of apoptosis and sensitivity of mutant cells to SKI treatment is mediated by EGFR and EGFR downstream pathways. Cotreatment with SKI-1 and gefitinib enhanced apoptosis in cancer cells that contained EGFR mutation and/or amplification. SKI-1 treatment alone induced significant apoptosis in H1975 cells known to be resistant to gefitinib. Src phosphorylation was shown by immunohistochemistry in around 30% of primary lung carcinomas. In 152 adenocarcinomas studied, p-Src was associated with EGFR mutations (P = 0.029). Overall, the findings indicated that Src could be a useful target for treatment of non–small cell lung cancer. Besides EGFR genomic mutations, other forms of EGFR and related family member abnormalities such as EGFR amplification might enhance SKI sensitivity. (Mol Cancer Res 2009;7(6):923–32)
Modulation by Phenethyl Isothiocyanate and Budesonide of Molecular and Histopathologic Alterations Induced by Environmental Cigarette Smoke in Mice
Authors: D'Agostini Francesco , Mastracci Luca , Izzotti Alberto , Balansky Roumen , Pennisi Tanya M. , Steele Vernon E. , De Flora Silvio
Published: June 2009

Our discovery that the perinatal period involves nucleotide modifications and gene overexpression in mouse lung prompted us to evaluate whether mice may become more susceptible to cigarette smoke when exposure starts immediately after birth. We previously showed that mainstream cigarette smoke is a quite potent carcinogen in neonatal mice. Further on, we showed that exposure of mice to environmental cigarette smoke (ECS), starting at birth, results in alterations of a variety of intermediate biomarkers. However, after 4 months of exposure to ECS followed by 7 months of recovery in filtered air, the lung tumor yield was rather low. In the present study, we evaluated the protective effects of the glucocorticoid budesonide and of the dietary agent phenethyl isothiocyanate in mice exposed to ECS for 9 months followed by 2 months of recovery. After weanling, the mice exposed to ECS since birth underwent a variety of alterations of molecular and cytogenetical end points, and 11 months after birth, they exhibited significant histopathologic changes, such as pulmonary anthracosis, emphysema, hemorrhagic areas, alveolar bronchiolarization, bronchial hyperplasia, and tumors, both benign and malignant. The carcinogenic response was less evident in dams exposed to ECS under identical conditions. Both phenethyl isothiocyanate and budesonide, administered daily with the diet after weanling, attenuated several alterations of ECS-related biomarkers and moderately protected the lungs from histopathologic alterations, including tumors. Thus, although not as efficiently as the bioassay in mainstream cigarette smoke–exposed mice, the model in neonatal mice is suitable to evaluate both ECS carcinogenicity and its modulation by chemopreventive agents.
Molecular Profiles of Finasteride Effects on Prostate Carcinogenesis
Authors: Li Jin , Kim Jeri
Published: June 2009

Our inability to distinguish between low-grade prostate cancers that pose no threat and those that can kill compels newly diagnosed early prostate cancer patients to make decisions that may negatively affect their lives needlessly for years afterward. To reliably stratify patients into different risk categories and apply appropriate treatment, we need a better molecular understanding of prostate cancer progression. Androgen ablation therapy and 5-α reductase inhibitors reduce dihydrotestosterone levels and increase apoptosis. Because of the differing biological potentials of tumor cells, however, these treatments may, in some cases, worsen outcome by selecting for or inducing adaptation of stronger androgen receptor signaling pathways. Reduced dihydrotestosterone also may be associated with altered survival pathways. Complicating treatment effects further, molecular adaptation may be accelerated by interactions between epithelial and stromal cells. The hypothesis that early prostate cancer cells with differing biological potential may respond differently to finasteride treatment is worth testing. Ongoing studies using a systems biology approach in a preoperative prostate cancer setting are testing this hypothesis toward developing more-rational clinical interventions.
Long-Term Paclitaxel-Eluting Stent Outcomes in Elderly Patients
Authors: Forman Daniel E. , Cox David A. , Ellis Stephen G. , Lasala John M. , Ormiston John A. , Stone Gregg W. , Turco Mark A. , Wei Jeanne Y. , Joshi Anita A. , Dawkins Keith D. , Baim Donald S.
Published: June 2009

Background—

Although drug-eluting stents have become a mainstay of percutaneous coronary intervention, information about drug-eluting stents outcomes in elderly patients is limited. Data from the paclitaxel-eluting stent (PES) trials and registries were pooled to assess PES benefits relative to advancing patient age, including comparison with bare-metal stents.

Methods and Results—

Data from 5 randomized trials (2271 patients with PES, 1397 patients with bare-metal stents) and from 2 postmarket registries (7492 patients with PES) were pooled separately. Each dataset was stratified into age groups: <60, 60 to 70, and >70 years. At baseline, patients aged >70 years in both datasets had significantly more adverse characteristics than younger patients. Through 5 years, trial data showed that patients aged >70 years had higher death rates, but comparable rates of myocardial infarction, stent thrombosis, and target lesion revascularization with younger patients. Compared with patients with bare-metal stents, patients with PES aged >70 years had comparable rates of death, myocardial infarction, and stent thrombosis but a significantly lower target lesion revascularization rate (22.2 versus 10.2,
P
<0.001). These findings were echoed in the registry data through 2 years that showed that PES patients aged >70 years had significantly higher death rates, but lower myocardial infarction, stent thrombosis, and target lesion revascularization rates, compared with younger patients. Although the mortality rates of patients aged >70 years were higher than those of younger patients, they were comparable with those of age- and gender-matched norms in the general population.

Conclusions—

This analysis of almost 10 000 patients demonstrated that percutaneous coronary intervention with PES is a safe and an effective treatment option that should not be withheld based on age.
Quantitative Results of Baseline Angiography and Percutaneous Coronary Intervention in the COURAGE Trial
Authors: Mancini G.B. John , Bates Eric R. , Maron David J. , Hartigan Pamela , Dada Marcin , Gosselin Gilbert , Kostuk William , Sedlis Steven P. , Shaw Leslee J. , Berman Daniel S. , Berger Peter B. , Spertus John , Mavromatis Kreton , Knudtson Merril , Chaitman Bernard R. , O'Rourke Robert A. , Weintraub William S. , Teo Koon , Boden William E.
Published: June 2009

Background—

COURAGE compared outcomes in stable coronary patients randomized to optimal medical therapy plus percutaneous coronary intervention (PCI) versus optimal medical therapy alone.

Methods and Results—

Angiographic data were analyzed by treatment arm, health care system (Veterans Administration, US non–Veterans Administration, Canada), and gender. Veterans Administration patients had higher prevalence of coronary artery bypass graft surgery and left ventricular ejection fraction ≤50%. Men had worse diameter stenosis of the most severe lesion, higher prevalence of prior coronary artery bypass graft surgery, lower left ventricular ejection fraction, and more 3-vessel disease that included a proximal left anterior descending lesion (
P
<0.0001 for all comparisons versus women). Failure to cross rate (3%) and visual angiographic success of stent procedures (97%) were similar to contemporary practice in the National Cardiovascular Data Registry. Quantitative angiographic PCI success was 93% (residual lesion <50% in-segment) and 82% (<20% in-stent), with only minor nonsignificant differences among health care systems and genders. Event rates were higher in patients with higher jeopardy scores and more severe vessel disease, but rates were similar irrespective of treatment strategy. Within the PCI plus optimal medical therapy arm, complete revascularization was associated with a trend toward lower rate of death or nonfatal myocardial infarction. Complete revascularization was similar between genders and among health care systems.

Conclusions—

PCI success and completeness of revascularization did not differ significantly by health care system or gender and were similar to contemporary practice. Angiographic burden of disease affected overall event rates but not response to an initial strategy of PCI plus optimal medical therapy or optimal medical therapy alone.
Extent of the Decrease of 28-Day Case Fatality of Hospitalized Patients With Acute Myocardial Infarction Over 22 Years
Authors: Kuch Bernhard , von Scheidt Wolfgang , Ehmann Anja , Kling Birgitt , Greschik Claudia , Hoermann Allmut , Meisinger Christa
Published: June 2009

Background—

No data exist regarding time trends of 28-day case fatality (CF) of patients with presumed acute myocardial infarction (AMI) using epidemiological criteria, clinical criteria, and AMI classification after validation of presumed in-hospital AMI-related deaths (gold-standard criteria).

Methods and Results—

From 1985 to 2004, we prospectively examined all 9210 AMI patients consecutively hospitalized in a large teaching hospital by using a broad epidemiological AMI definition (WHO-MONICA). Twenty-eight-day CF decreased significantly from 32% in 1985–1986 to 18% in 2003–2004, mostly because of a reduction in early deaths (<24 hours). When applying the clinical AMI definition, most of the early deaths were not counted as AMI related. A retrospective validation process from a sample of all early deceased patients by the epidemiological AMI definition (388/2076) and a prospective validation of the complete cohort in 2005–2006 revealed that only about 50% of early deaths are reclassified as a real fatal AMI using newer criteria resulting in a 28-day CF of 23% in 1985–1986 and 11% in 2005–2006. The difference between the AMI 28-day CF by applying gold-standard criteria and the clinical AMI 28-day CF (18% in 1985–1986 and 7% in 2005–2006) has decreased during recent years.

Conclusions—

The application of broad epidemiological criteria for AMI overestimates 28-day CF by almost 2-fold compared with gold-standard criteria (after validation of early deaths) and almost 3-fold compared to the clinical definition. The growing similarity in 28-day CF between the clinically based definition and the gold-standard criteria implies that recent clinical-based registries may represent a realistic picture of trends regarding in-hospital AMI mortality.
The Role of Convective Moistening in the Madden–Julian Oscillation
Authors: Thayer-Calder Katherine , Randall David A.
Published: June 2009

This study compares two models that differ primarily in their cloud parameterizations and produce extremely different simulations of the Madden–Julian oscillation (MJO). The Community Atmosphere Model (CAM) version 3.0 from NCAR uses the Zhang–McFarlane scheme for deep convection and does not produce an MJO. The “superparameterized” version of the CAM (SP-CAM) replaces the cloud parameterizations with a two-dimensional cloud-resolving model (CRM) in each grid column and produces an extremely vigorous MJO.

This analysis shows that the CAM is unable to produce high-humidity regions in the mid- to lower troposphere because of a lack of coupling between parameterized convection and environmental relative humidity. The SP-CAM produces an overly moist column due in part to excessive near-surface winds and evaporation during strong convective events. In the real tropics and the SP-CAM, convection within a high-humidity environment produces intense latent heating, which excites the large-scale circulation that is the signature of the MJO. The authors suggest that a model must realistically represent convective processes that moisten the entire tropical troposphere in order to produce a simulation of the MJO.
Topographic Influence on the MJO in the Maritime Continent
Authors: Wu Cheng-Han , Hsu Huang-Hsiung
Published: June 2009

This study demonstrates that during the passage of the MJO through the Maritime Continent in the boreal winter, the corresponding deep convection and near-surface wind anomalies tend to skirt around mountainous islands. Flow bifurcation around elongated mountainous islands, such as New Guinea, is clearly seen. Topographic blocking generates distinctive vorticity and convergence distributions in this specific domain. Mountain-wave-like structures are also observed throughout the Maritime Continent, with a clear spatial relationship with the high terrains in Sumatra, Sulawesi, and New Guinea. The existence of topography seems to create extra lifting and sinking within the large-scale circulation and thus the convective system exhibits quasi-stationary features near the major topography during the MJO passage through the Maritime Continent. It is suggested that resolving the detailed topographic effects may play a key role in simulating realistic characteristics of the MJO in the Maritime Continent.