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ABSTRACT: BACKGROUND: Vascular endothelial growth factor-a (VEGF)-targeted therapies have become an important treatment for a number of human malignancies. The VEGF inhibitors are actually effective in several types of cancers, however, the benefits are transiently, and the vast majority of patients who initially respond to the therapies will develop resistance. One of possible mechanisms for the acquired resistance may be the direct effect(s) of VEGF inhibitors on tumor cells expressing VEGF receptors (VEGFR). Thus, we investigated here the direct effect of chronic VEGF inhibition on phenotype changes in human colorectal cancer (CRC) cells. METHODS: To chronically inhibit cancer cell-derived VEGF, human CRC cell lines (HCT116 and RKO) were chronically exposed (2 months) to an anti-VEGF monoclonal antibody (mAb) or were disrupted the Vegf gene (VEGF-KO). Effects of VEGF family members were blocked by treatment with a VEGF receptor tyrosine kinase inhibitor (VEGFR-TKI). Hypoxia-induced apoptosis under VEGF inhibited conditions was measured by TUNEL assay. Spheroid formation ability was assessed using a 3-D spheroid cell culture system. RESULTS: Chronic inhibition of secreted/extracellular VEGF by an anti-VEGF mAb redundantly increased VEGF family member (PlGF, VEGFR1 and VEGFR2), induced a resistance to hypoxia-induced apoptosis, and increased spheroid formation ability. This apoptotic resistance was partially abrogated by a VEGFR-TKI, which blocked the compensate pathway consisted of VEGF family members, or by knockdown of Vegf mRNA, which inhibited intracellular function(s) of all Vegf gene products. Interestingly, chronic and complete depletion of all Vegf gene products by Vegf gene knockout further augmented these phenotypes in the compensate pathway-independent manner. These accelerated phenotypes were significantly suppressed by knockdown of hypoxia-inducible factor-1alpha that was up-regulated in the VEGF-KO cell lines. CONCLUSIONS: Our findings suggest that chronic inhibition of tumor cell-derived VEGF accelerates tumor cell malignant phenotypes.
BMC Cancer 05/2013; 13(1):229. · 3.01 Impact Factor
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ABSTRACT: BACKGROUND: Transformer (Tra) 2β is a member of the serine/arginine-rich (SR)-like protein family that regulates alternative splicing of numerous genes in a concentration-dependent manner. Several types of cancer cells up-regulate Tra2β expression, while the regulatory mechanism of Tra2β expression remains to be elucidated. In this study, we examined the transcriptional regulation and possible functions of Tra2β in human colon cancer cells. METHODS: We cloned 959 bp-upstream of the human TRA2β 5'-flank into luciferase constructs. Chromatin immunoprecipitation (ChIP) was employed to identify crucial cis element(s) and trans activator(s) of the TRA2β promoter. Tra2β expression in the human colon and colon cancer tissues was examined by immunohistochemistry. RESULTS: In response to sodium arsenite, colon cancer cells (HCT116) increased levels of TRA2β1 mRNA encoding a functional, full-length Tra2β with a peak around 6 h without changing its mRNA stability. Transient expression assays using a reporter gene driven by serially truncated TRA2β promoters and Chip assay demonstrated that an Ets1-binding site present at -64 to -55 bp was crucial for basal transcription, while three heat shock elements (HSEs) located at -145 to -99 bp mediated the oxidant-induced transactivation of TRA2β. Tra2β knockdown caused apoptosis of HCT116 cells. Tra2β were preferentially expressed in proliferative compartment of normal human colonic glands and adenocarcinomas, where Ets1 and heat shock factor 1 were also highly expressed. CONCLUSIONS: Our results suggest that oxidative stress-responsive Tra2β may play an important role in colon cancer growth.
Journal of Gastroenterology 01/2013; · 4.16 Impact Factor
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ABSTRACT: Non-coding microRNAs (miRNAs) are suggested to serve fundamental roles in cellular stress responses and in coping with sudden environmental changes in experimental animals. We examined whether naturalistic stressor-responsive miRNAs were detectable in whole blood. Blood and saliva were collected between 16:00 and 17:00 from 10 healthy medical students (5 males and 5 females; aged 22.4±0.8 years, mean±SD) 7 weeks before, one day before, immediately after, and one week after a nationally administered examination for academic promotion. Samples obtained one week after the examination were used as baseline controls. State anxiety and salivary cortisol levels reached maximum levels the day before the examination. Eleven candidate miRNAs (miR-144, -144*, -16, -15a, -19a, -19b, -26b, -30b, -106b, -126, and -142-3p) were extracted using a human miRNA microarray, and quantitative real-time reverse transcription PCR confirmed significant elevation of miR-144/144* and miR-16 levels immediately after finishing the examination. miR-16 levels in individual students were positively correlated with those of serum tumor necrosis factor (TNF)-α measured immediately after the examination. Percentage changes in miR-144* and miR-16 levels from immediately after to one week after the examination were significantly correlated with percentage changes in circulating interferon-γ and/or TNF-α levels over the same time points. Our results suggest that miR-144/144* and miR-16 may constitute a part of an integrated response to naturalistic stressors in healthy young adults.
Neuroscience Letters 03/2012; 516(1):79-84. · 2.11 Impact Factor
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Ken Kurokawa,
Toshihito Tanahashi,
Tsutomu Iima,
Yuta Yamamoto,
Yoko Akaike, Kensei Nishida,
Kiyoshi Masuda,
Yuki Kuwano,
Yoshiki Murakami,
Masakazu Fukushima,
Kazuhito Rokutan
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ABSTRACT: Drug resistance in colorectal cancers is assumed to be mediated by changes in the expression of microRNAs, but the specific identities and roles of microRNAs are largely unclear. We examined the effect of 5-fluorouracil (5-FU) resistance on microRNA expression.
Two types of 5-FU-resistant colon cancer cells were derived from the DLD-1 and KM12C cell lines. The expressions of microRNAs were profiled with a microarray containing 723 microRNAs and validated by quantitative real-time polymerase chain reaction (qRT-PCR). To survey the downstream mediators of microRNA, we used a microRNA:mRNA immunoprecipitation (RIP)-Chip and pathway analysis tool to identify potential direct targets of microRNA.
In response to 5-FU, miR-19b and miR-21 were over-expressed in 5-FU-resistant cells. Of note, miR-19b was up-regulated 3.47-fold in the DLD-1 resistant cells, which exhibited no alteration in cell cycle profiles despite exposure to 5-FU. After transfection of miR-19b, specific mRNAs were recruited to microRNA:mRNA complexes isolated with Ago2 antibody and subjected to whole-genome transcriptional analysis. In this analysis, 66 target mRNAs were enriched by at least 5.0-fold in the microRNA:mRNA complexes from DLD-1 resistant cells. Ingenuity pathway analysis of mRNA targets significantly (P < 0.05) indicated the category "Cell Cycle" as a probable area of the molecular and cellular function related with 5-FU resistance. Among candidate mRNA targets, SFPQ and MYBL2 have been linked to cell cycle functions.
We revealed up-regulation of miR-19b in response to 5-FU and potential targets of miR-19b mediating the cell cycle under treatment with 5-FU. Our study provides an important insight into the mechanism of 5-FU resistance in colorectal cancers.
Journal of Gastroenterology 03/2012; 47(8):883-95. · 4.16 Impact Factor
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ABSTRACT: Gene expression patterns vary dramatically in a tissue-specific and age-dependent manner. RNA-binding proteins that regulate mRNA turnover and/or translation (TTR-RBPs) critically affect the subsets of expressed proteins. Although many proteins implicated in age-related processes are encoded by mRNAs that are targets of TTR-RBPs, very little is known regarding the tissue- and age-dependent expression of TTR-RBPs in humans. Recent analysis of TTR-RBPs expression using human tissue microarray has provided us interesting insight into their possibly physiologic roles as a function of age. This analysis has also revealed striking discrepancies between the levels of TTR-RBPs in senescent human diploid fibroblasts (HDFs), widely used as an in vitro model of aging, and the levels of TTR-RBPs in tissues from individuals of advancing age. In this article, we will review our knowledge of human TTR-RBP expression in different tissues as a function of age.
Ageing research reviews 02/2012; 11(4):423-31. · 5.62 Impact Factor
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ABSTRACT: The srsf1 gene encodes serine/arginine-rich splicing factor 1 (SRSF1) that participates in both constitutive and alternative splicing reactions. This gene possesses two ultraconserved elements in the 3' untranslated region (UTR). Skipping of an alternative intron between the two elements has no effect on the protein-coding sequence, but it generates a premature stop codon (PTC)-containing mRNA isoform, whose degradation is considered to depend on nonsense-mediated mRNA decay (NMD). However, several cell lines (HCT116, RKO, HeLa, and WI38 cells) constitutively expressed significant amounts of the srsf1 PTC variant. HCT116 cells expressed the PTC variant nearly equivalent to the major isoform that includes the alternative intron in the 3' UTR. Inhibition of NMD by silencing a key effecter UPF1 or by treatment with cycloheximide failed to increase amounts of the PTC variant in HCT116 cells, and the PTC variant was rather more stable than the major isoform in the presence of actinomycin D. Our results suggest that the original stop codon may escape from the NMD surveillance even in skipping of the alternative intron. The srsf1 gene may produce an alternative splice variant having truncated 3' UTR to relief the microRNA- and/or RNA-binding protein-mediated control of translation or degradation.
The Journal of Medical Investigation 08/2011; 58(3-4):180-7.
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ABSTRACT: Anxiety and depressive mood are sometimes accompanied by modulation of neuroendocrine and immune functions. The aim of this study was to identify circulating immune mediators reflecting anxiety and depressive mood in healthy young adults.
Anxiety and depressive mood in 209 healthy medical students (125 males and 84 females, aged 20.7±2.7years (mean±SD)) were assessed by the Spielberger state-trait anxiety inventory (STAI) and the Zung self-rating depression scale (Zung-SDS), respectively. Cortisol and chromogranin A (CgA) levels in saliva were measured using enzyme immunoassay kits, and 50 different mediators in sera were measured by a multiplex-suspension array system. The level of statistical significance was set at α=0.05.
Forty-four mediators were measurable in sera, and each mediator showed substantial individual variations. After determining Pearson correlation coefficients, we selected candidate cytokines whose levels were associated with STAI-state (2 cytokines), STAI-trait (8 cytokines), or SDS scores (8 cytokines). The candidate cytokines plus interleukin (IL)-1β, IL-6, tumor necrosis factor-α, and macrophage migration inhibitory factor were then subjected to multiple regression analysis adjusted for gender, BMI, and salivary concentrations of cortisol and CgA. Vascular endothelial growth factor (VEGF) was independently and negatively associated with both trait anxiety (p<0.05) and depressive mood (p<0.01). IL-1β showed independently positive association with depressive mood (p<0.05). Interactions between these two cytokines and gender or BMI were not observed.
Besides IL-1β, circulating VEGF may be a potential biomarker for negative mood states in healthy young adults.
International journal of psychophysiology: official journal of the International Organization of Psychophysiology 07/2011; 81(1):38-43. · 3.05 Impact Factor
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ABSTRACT: Chronic academic stress responses were assessed by measuring mental state, salivary cortisol levels, and the glucocorticoid receptor (GR) gene expression in healthy Japanese medical students challenging the national medical license examination. Mental states of 17 male and 9 female medical undergraduates, aged 25.0 ± 1.2 years (mean ± SD), were assessed by the State and Trait Anxiety Inventory (STAI) and the Self-Rating Depression Scale (SDS) 2 months before, 2 days before, and 1 month after the examination. At the same time points, saliva and blood were collected. STAI-state scores peaked 2 days before the examination. Scores on STAI-trait and SDS, and salivary cortisol levels were consistently higher during the pre-examination period. One month after the examination, all these measures had significantly decreased to baseline levels. Real-time reverse transcription PCR showed that this chronic anxious state did not change the expression of the functional GRα mRNA isoform in peripheral leukocytes, while it resulted in reduced expression of the GRβ isoform 2 days before the examination. Our results replicate and extend a significant impact of chronic academic stressors on the mental state of healthy Japanese medical students and suggest a possible association of GRβ gene in response to psychological stress.
Stress (Amsterdam, Netherlands) 03/2011; 14(4):431-8. · 3.21 Impact Factor
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Yuta Yamamoto,
Toshihito Tanahashi,
Sakurako Katsuura,
Ken Kurokawa, Kensei Nishida,
Yuki Kuwano,
Tomoko Kawai,
Shigetada Teshima-Kondo,
Sachiko Chikahisa,
Yoshihiro Tsuruo,
Hiroyoshi Sei,
Kazuhito Rokutan
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ABSTRACT: In this study, we examined the effects of IL-18 deficiency on behaviors and gene expression profiles in 6 brain regions. IL-18(-/-) mice reduced depressive-like behavior and changed gene expressions predominantly in the amygdala compared with wild-type mice. Pathway analysis of the differentially expressed genes ranked behavior as the top-scored biological function. Of note, the absence of IL-18 decreased Avp, Hcrt, Oxt, and Pmch mRNA levels and the number of arginine vasopressin- and oxytocin-positive cells in the amygdala, but not in the hypothalamus. Our results suggest that IL-18-dependent vasopressinergic and oxytocinergic circuitry in the amygdala may regulate depressive-like behaviors in mice.
Journal of neuroimmunology 12/2010; 229(1-2):129-39. · 2.84 Impact Factor
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Sakurako Katsuura,
Yoshiko Kamezaki,
Kumiko Tominaga,
Kiyoshi Masuda, Kensei Nishida,
Yuta Yamamoto,
Keiko Takeo,
Naoko Yamagishi,
Toshihito Tanahashi,
Tomoko Kawai,
Kazuhito Rokutan
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ABSTRACT: This study was designed to prospectively examine the impact of a brief naturalistic stressor (academic examination) on salivary/serum cortisol, measures of anxiety and depressive mood, and 50 circulating immune mediators assessed 7 days before, the first day of, and 2 days after the first term examination period (5 days) among 20 male and 6 female medical students (19.7+/-3.1 years, mean+/-SD). Of 42 serum factors detected, repeated measures ANOVA and Bonferroni post hoc testing indicated that concentrations of macrophage migration inhibitory factor (MIF), monocyte chemoattractant protein (MCP)-3, and beta-nerve growth factor (beta-NGF) were significantly decreased 2 days after finishing examinations, compared with the levels on the first day of examinations (p<0.05) in association with a concomitant post-examination decreases (p<0.05) in anxiety and salivary cortisol levels. In contrast, interleukin (IL)-16 was reciprocally increased between the two time points (p<0.05). However, after correction for multiple comparisons, only changes in MIF were significant (p<0.05/42=0.00119), and MIF levels peaked on the first day of examinations was significantly higher than those measured both 7 days before and 2 days after the examination. The present high-throughput analysis with multiplex cytokine panels reconfirms the impact of brief naturalistic stressors on immune outcomes, and suggests a potential role of MIF in the acute stress response.
International journal of psychophysiology: official journal of the International Organization of Psychophysiology 08/2010; 77(2):135-40. · 3.05 Impact Factor
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ABSTRACT: Caloric restriction (CR) is an effective method for prevention of age-associated diseases as well as overweight and obesity; however, there is controversy regarding the effects of dieting regimens on behavior. In this study, we investigated two different dieting regimens: repeated fasting and refeeding (RFR) and daily feeding of half the amount of food consumed by RFR mice (CR). CR and RFR mice had an approximate 20% reduction in food intake compared with control mice. Open field, light-dark transition, elevated plus maze, and forced swimming tests indicated that CR, but not RFR, reduced anxiety- and depressive-like behaviors, with a reduction peak on day 8. Using a mouse whole genome microarray, we analyzed gene expression in the prefrontal cortex, amygdala, and hypothalamus. In addition to the CR-responsive genes commonly modified by RFR and CR, each regimen differentially changed the expression of distinct genes in each region. The most profound change was observed in the amygdalas of CR mice: 884 genes were specifically upregulated. Ingenuity pathway analysis revealed that these 884 genes significantly modified nine canonical pathways in the amygdala. alpha-Adrenergic and dopamine receptor signalings were the two top-scoring pathways. Quantitative RT-PCR confirmed the upregulation of six genes in these pathways. Western blotting confirmed that CR specifically increased dopamine- and cAMP-regulated phosphoprotein (Darpp-32), a key regulator of dopamine receptor signaling, in the amygdala. Our results suggest that CR may change behavior through altered gene expression.
Physiological Genomics 10/2009; 39(3):227-35. · 2.73 Impact Factor
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ABSTRACT: NADPH oxidase 1 (Nox1) is preferentially expressed in the colon, but its functional role is not fully understood. This study was designed to elucidate a potential role of Nox1 in inflammation of the colon.
Superoxide production by T84 cells was measured by the cytochrome c method. Protein and mRNA levels of Nox1 and Nox organizer 1 (NOXO1) in the cells were measured by real-time reverse transcriptase PCR and Western blotting, respectively. Expression of Nox1, Nox2, dual oxidase 2 (Duox2), NOXO1, interferon (IFN)-gamma, and tumor necrosis factor (TNF)-alpha mRNAs was measured in proximal, middle, and distal portions of colonic mucosas from male wild-type C57BL/6J and interleukin (IL)-10 knockout mice at 6, 10, and 16 weeks of age. Grading of inflammation was done by scoring histological changes.
IL-10 significantly inhibited IFN-gamma- or TNF-alpha-induced up-regulation of superoxide-producing activity in T84 cells by suppressing expression of Nox1 mRNA and protein. IL-10 also inhibited TNF-alpha-stimulated induction of NOXO1 and p38 MAPK phosphorylation. Levels of Nox1, but not Nox2 or Duox2 mRNA, was age-dependently increased following a gradient with low levels in the proximal colon and high levels in the distal colon of the wild-type mice. The absence of IL-10 significantly facilitated Nox1 expression in association with increased IFN-gamma mRNA expression before the development of spontaneous colitis and age-dependently accelerated their mRNA expression.
IL-10 may be a possible down-regulator of the Nox1-based oxidase in the colon, suggesting a potential role of reactive oxygen species (ROS) derived from Nox1-based oxidase in inflammation of the colon.
Journal of Gastroenterology 09/2009; 44(12):1172-84. · 4.16 Impact Factor
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ABSTRACT: The tra2beta gene encoding an alternative splicing regulator, transformer 2-beta (Tra2beta), generates five alternative splice variant transcripts (tra2beta1-5). Functionally active, full-length Tra2beta is encoded by tra2beta1 isoform. Expression and physiological significance of the other isoforms, particularly tra2beta4, are not fully understood. Rat gastric mucosa constitutively expressed tra2beta1 isoform and specifically generated tra2beta4 isoform that includes premature termination codon-containing exon 2, when exposed to restraint and water immersion stress. Treatment of a gastric cancer cell line (AGS) with arsenite (100 microM) preferentially generated tra2beta4 isoform and caused translocation of Tra2beta from the nucleus to the cytoplasm in association with enhanced phosphorylation during the initial 4-6 h (acute phase). Following the acute phase, AGS cells continued upregulated tra2beta1 mRNA expression, and higher amounts of Tra2beta were reaccumulated in their nuclei. Treatment with small interference RNAs targeting up-frameshift-1 or transfection of a plasmid containing tra2beta1 cDNA did not induce tra2beta4 isoform expression and did not modify the arsenite-induced expression of this isoform, suggesting that neither the nonsense-mediated mRNA decay nor the autoregulatory control by excess amounts of Tra2beta participated in the tra2beta4 isoform generation. Knockdown of Tra2beta facilitated skipping of the central variable region of the CD44 gene and suppressed cell growth. In contrast, overexpression of Tra2beta stimulated combinatorial inclusion of multiple variable exons in the region and cell growth. The similar skipping and inclusion of the variable region were observed in arsenite-treated cells. Our results suggest that Tra2beta may regulate cellular oxidative response by changing alternative splicing of distinct genes including CD44.
AJP Cell Physiology 06/2009; 297(2):C330-8. · 3.54 Impact Factor
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ABSTRACT: Psychosocial factors are important determinants of disease manifestations, treatment efficacy, and prognosis of functional and inflammatory bowel disorders. Isolation of C57BL/6J mice from their 4 brothers growing in the same cage reduced goblet cells and MUC2 expression with a peak on day 8 in the rectum, but not in the colon. Gene expression analysis using a whole mouse genome microarray showed that the stress induced a 10-fold larger change in the gene expression in the rectum (722 genes) than in the colon (72 genes). The Ingenuity Pathway Analysis (IPA) application organized the rectum-specific 711 genes into stress response-related pathways. Nuclear factor-kappaB-related cytokine networks constructed with IPA showed selective up-regulation of interleukin (IL)-18 mRNA expression, which was also confirmed by real-time polymerase chain reaction. The stress produced active forms of caspase 1, IL-18, and a negative regulator for goblet cells, Notch 1, only in the rectum. IL-18-knockout mouse rectum had significantly increased goblet cells and MUC2 mucin, compared with wild-type mouse rectum. The absence of IL-18 completely blocked the stress-induced changes in gene expression and the goblet cell responses in the rectum. Thus, IL-18 may be a crucial determinant for the vulnerability of the rectum to psychosocial stress.
The FASEB Journal 02/2009; 23(6):1797-805. · 5.71 Impact Factor
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ABSTRACT: NADPH oxidase 1 (Nox1) is a multicomponent enzyme consisting of p22(phox), Nox organizer 1 (NOXO1), Nox1 activator 1, and Rac1. Interleukin-1beta, flagellin, interferon-gamma, and tumor necrosis factor alpha (TNF-alpha) similarly induced Nox1 in a colon cancer cell line (T84), whereas only TNF-alpha fully induced NOXO1 and upregulated superoxide-producing activity by ninefold. This upregulation was canceled by knockdown of NOXO1 with small interfering RNAs. TNF-alpha rapidly phosphorylated p38 mitogen-activated protein kinase and c-Jun N-terminal kinase 1/2, followed by phosphorylation of c-Jun and c-Fos and appearance of an AP-1 binding activity within 30 min. We cloned the 5' flank of the human NOXO1 gene (-3888 to +263 bp), and found that the region between -585 and -452 bp, which contains consensus elements of YY-1, AP-1, and Ets, and the GC-rich region encoding three putative binding sites for SP-1, was crucial for TNF-alpha-dependent promoter activity. Serial mutation analysis of the elements identified an AP-1 binding site (from -561 to -551 bp, agtAAGtcatg) as a crucial element for TNF-alpha-stimulated transcription of the human NOXO1 gene, which was also confirmed by the AP-1 decoy experiments. Thus, TNF-alpha acts as a potent activator of Nox1-based oxidase in colon epithelial cells, suggesting a potential role of this oxidase in inflammation of the colon.
Free Radical Biology and Medicine 10/2008; 45(12):1642-52. · 5.42 Impact Factor
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ABSTRACT: Vascular endothelial growth factor-A (VEGF) is one of the key regulators of tumor development, hence it is considered to be an important therapeutic target for cancer treatment. However, clinical trials have suggested that anti-VEGF monotherapy was less effective than standard chemotherapy. On the basis of the evidence, we hypothesized that vegf mRNA may have unrecognized function(s) in cancer cells.
Knockdown of VEGF with vegf-targeting small-interfering (si) RNAs increased susceptibility of human colon cancer cell line (HCT116) to apoptosis caused with 5-fluorouracil, etoposide, or doxorubicin. Recombinant human VEGF165 did not completely inhibit this apoptosis. Conversely, overexpression of VEGF165 increased resistance to anti-cancer drug-induced apoptosis, while an anti-VEGF165-neutralizing antibody did not completely block the resistance. We prepared plasmids encoding full-length vegf mRNA with mutation of signal sequence, vegf mRNAs lacking untranslated regions (UTRs), or mutated 5'UTRs. Using these plasmids, we revealed that the 5'UTR of vegf mRNA possessed anti-apoptotic activity. The 5'UTR-mediated activity was not affected by a protein synthesis inhibitor, cycloheximide. We established HCT116 clones stably expressing either the vegf 5'UTR or the mutated 5'UTR. The clones expressing the 5'UTR, but not the mutated one, showed increased anchorage-independent growth in vitro and formed progressive tumors when implanted in athymic nude mice. Microarray and quantitative real-time PCR analyses indicated that the vegf 5'UTR-expressing tumors had up-regulated anti-apoptotic genes, multidrug-resistant genes, and growth-promoting genes, while pro-apoptotic genes were down-regulated. Notably, expression of signal transducers and activators of transcription 1 (STAT1) was markedly repressed in the 5'UTR-expressing tumors, resulting in down-regulation of a STAT1-responsive cluster of genes (43 genes). As a result, the tumors did not respond to interferon (IFN)alpha therapy at all. We showed that stable silencing of endogenous vegf mRNA in HCT116 cells enhanced both STAT1 expression and IFNalpha responses.
These findings suggest that cancer cells have a survival system that is regulated by vegf mRNA and imply that both vegf mRNA and its protein may synergistically promote the malignancy of tumor cells. Therefore, combination of anti-vegf transcript strategies, such as siRNA-based gene silencing, with anti-VEGF antibody treatment may improve anti-cancer therapies that target VEGF.
PLoS Medicine 06/2008; 5(5):e94. · 16.27 Impact Factor
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ABSTRACT: To assess response to chronic psychological stress, gene expression profiles in peripheral blood from 18 medical students confronting license examination were analyzed using an original microarray. Total RNA was collected from each subject 9 months before the examination and mixed to be used as a universal control. At that time, most students had normal scores on the state-trait anxiety inventory (STAI). However, STAI scores were significantly elevated at 2 months and at 2 days before the examination. Pattern of the gene expression profile was more uniform 2 days before than 2 months before the examination. We identified 24 genes that significantly and uniformly changed from the universal control 2 days before the examination. Of the 24 genes, real-time PCR validated changes in mRNA levels of 10 (PLCB2, CSF3R, ARHGEF1, DPYD, CTNNB1, PPP3CA, POLM, IRF3, TP53, and CCNI). The identified genes may be useful to assess chronic psychological stress response.
Biological Psychology 11/2007; 76(3):147-55. · 3.22 Impact Factor
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ABSTRACT: To assess response to physical stress, gene expression profiles in peripheral blood cells were analyzed using an original microarray carrying 1467 stress-responsive complementary DNA probes.
Gene expression was analyzed at 4, 24, and 48 hours after exercising on a cycle ergometer at 60% VO2 max for 1 hour (aerobic exercise) or until exhausted (exhaustive exercise).
Institute of Health Biosciences, University of Tokushima Graduate School.
Twelve healthy male students of the postgraduate or undergraduate school.
The volunteers performed the aerobic or exhaustive exercise on a cycle ergometer.
Detection of aerobic exercise-responsive or exhaustive exercise-responsive genes in peripheral blood cells.
Aerobic and exhaustive exercise transiently changed the expression of 21 and 16 genes, respectively, with the peak at 4 hours. Only 2 genes significantly responded to both types of exercise. Exhaustive but not aerobic exercise produced a secondary response with significantly altered expression of 14 genes at 24 hours. Five of those genes encode receptors for neurotransmitters (HTR1A, CHRNB2, GABRB3, GABRG3, and LOC51289).
The behavior of the individual genes shown here may be informative to objectively assess acute physical stress and exhaustion-associated responses.
Clinical Journal of Sport Medicine 10/2007; 17(5):375-83. · 2.12 Impact Factor
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Atsuo Sekiyama,
Haruyasu Ueda,
Shin-ichiro Kashiwamura, Kensei Nishida,
Seiko Yamaguchi,
Hideyuki Sasaki,
Yuki Kuwano,
Kaori Kawai,
Shigetada Teshima-Kondo,
Kazuhito Rokutan,
Haruki Okamura
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ABSTRACT: To reveal a pathway by which psychological/physical stresses influence host defense capability, responses to immobilization stress in mice were investigated, focusing on a multifunctional cytokine, interleukin-18 (IL-18). Immobilization stress induced interleukin-18 accumulation in plasma and in the adrenal gland. Inhibition on ACTH resulted in suppressed levels of IL-18 both in plasma and the adrenal gland. In hemi-adrenalectomized mice, plasma IL-18 levels after stress were lower than in sham-operated mice. This, together with the observation in stressed hemi-adrenalectomized mice that IL-6 levels in plasma were suppressed but up-regulated by recombinant IL-18, showed that the adrenal gland plays a crucial role in stress-related elevation of IL-6 in plasma via IL-18. Adrenal gland is highlighted as an organ connecting the psychological, endocrine, and immune systems. Controlling the secretion of IL-18 from the adrenal gland may serve as a possible preventative means against a stress-related disruption of host defenses.
Journal of Neuroimmunology 03/2006; 171(1-2):38-44. · 2.96 Impact Factor
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ABSTRACT: Psychological/physical stresses have been reported to exacerbate auto-immune and inflammatory diseases. To clarify a mechanism by which non-inflammatory stresses disrupt host defenses, responses to immobilization stress in mice were investigated, focusing on the role of a multifunctional cytokine, interleukin-18 (IL-18). In the adrenal cortex, the stress induced IL-18 precursor proteins (pro-IL-18) via ACTH and a superoxide-mediated caspase-1 activation pathway, resulting in conversion of pro-IL-18 to the mature form which was released into plasma. Inhibitors of caspase-1, reactive oxygen species and P38 MAPK prevented stress-induced accumulation of plasma IL-18. These inhibitors also blocked stress-induced IL-6 expression. This, together with the observation that IL-6 was not induced in stressed-IL-18 deficient mice, showed that IL-6 induction by stress is dependent on IL-18. In stressed organisms, IL-18 may influence pathological and physiological processes. Controlling the caspase-1 activating pathway to suppress IL-18 levels may provide preventative means against stress-related disruption of host defenses.
The Journal of Medical Investigation 12/2005; 52 Suppl:236-9.
