MiR-29b is associated with perinatal inflammation in extremely preterm infants.

BACKGROUND: Inflammation is strongly associated with premature birth and neonatal morbidities. Increases in infant haptoglobin, haptoglobin-related protein (Hp&HpRP), and interleukin-6 (IL-6) levels are indicators of intra-amniotic inflammation (IAI) and have been linked to poor neonatal outcomes. Inflammation causes epigenetic changes, specifically suppression of miR-29 expression. The current study sought to determine whether miR-29b levels in cord blood or neonatal venous blood are associated with IAI, identified by elevated IL-6 and Hp, and subsequent clinical morbidities in the infant. METHODS: We tested 92 cord blood samples from premature newborns and 18 venous blood samples at 36 weeks corrected gestational age. MiR-29b, Hp&HpRP, and IL-6 were measured by polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. RESULTS: Decreased levels of miR-29b were observed in infants exposed to IAI with elevated Hp&HpRP and IL-6 levels and in infants delivered by spontaneous preterm birth. Lower miR-29 levels were also observed in women diagnosed with histological chorioamnionitis or funisitis and in infants with cerebral palsy. Higher levels of miR-29 were measured in infants small for gestational age and in venous samples from older infants. CONCLUSIONS: MiR-29 may be an additional biomarker of IAI and a potential therapeutic target for treating poor newborn outcomes resulting from antenatal exposure to IAI. IMPACT: Decreases in miR-29b are associated with intrauterine inflammation. Hp&HpRP increases are associated with decreased miR-29b. MiR-29b may be an additional biomarker for neonatal outcomes and a potential therapeutic target for intrauterine inflammation.

Altered glycosylation, expression of serum haptoglobin and alpha-1-antitrypsin in chronic hepatitis C, hepatitis C induced liver cirrhosis and hepatocellular carcinoma patients.

Liver cirrhosis with hepatitis C viral infection (HCV-LC) causes high risk to develop hepatocellular carcinoma (HCC). Besides diagnosis of liver cirrhosis by biochemical test, imaging techniques, assessment of structural liver damage by biopsy shows several disadvantages. Our aim was to monitor the changes in the expression level of serum proteins and their glycosylation pattern among chronic hepatitis C (HCV-CH), HCV-LC and HCC patients with respect to controls. 2D gel electrophoresis of HCV-CH, HCV-LC and HCC patients' sera showed several protein spots, which were identified by LC-MS. The change in the expression of two prominent protein spots, haptoglobin (Hp) and alpha 1-antitrypsin (AAT) was evaluated by western blot and ELISA. The changes in glycosylation pattern of these serum proteins were assayed using different lectins. Increased level of Hp and AAT was observed in HCV-LC and HCC patients' group whereas those were found to be present less in HCV-CH patient groups with respect to control as determined by ELISA using monoclonal antibodies. Decreased level of sialylation in both Hp and AAT was observed in HCV-LC and HCV-CH patients' group whereas increased level of sialylation was observed in HCC patient groups by ELISA using Sambucus nigra agglutinin. On the other hand increased level of fucosylation in two serum glycoproteins was observed in HCV-LC and HCC patients' group using Lens culinarris agglutinin. High glycan branching was found in HCV-LC and HCC patient groups in Hp but not in HCV-CH as determined by Datura stramonium agglutinin. However, there was no such change observed in glycan branching in AAT of HCV-CH and HCV-LC patients' groups, to the contrary high glycan branching was observed in HCC patients' group. Increased level of exposed galactose in both serum proteins was observed in both HCC patients' group as determined by Ricinus communis agglutinin. The present glycoproteomics study could predict the progression of HCV-CH, HCV-LC and HCC without the need of liver biopsy.

Improvement of prognostic performance in severely injured patients by integrated clinico-transcriptomics: a translational approach.

INTRODUCTION: Severe trauma triggers a systemic inflammatory response that contributes to secondary complications, such as nosocomial infections, sepsis or multi-organ failure. The present study was aimed to identify markers predicting complications and an adverse outcome of severely injured patients by an integrated clinico-transcriptomic approach. METHODS: In a prospective study, RNA samples from circulating leukocytes from severely injured patients (injury severity score ≥ 17 points; n = 104) admitted to a Level I Trauma Center were analyzed for dynamic changes in gene expression over a period of 21 days by quantitative RT-PCR. Transcriptomic candidates were selected based on whole genome screening of a representative discovery set (n = 10 patients) or known mechanisms of the immune response, including mediators of inflammation (IL-8, IL-10, TNF-α, MIF, C5, CD59, SPHK1), danger signaling (HMGB1, TLR2, CD14, IL-33, IL-1RL1), and components of the heme degradation pathway (HP, CD163, HMOX1, BLVRA, BLVRB). Clinical markers comprised standard physiological and laboratory parameters and scoring systems routinely determined in trauma patients. RESULTS: Leukocytes, thrombocytes and the expression of sphingosine kinase-1 (SPHK1), complement C5, and haptoglobin (HP) have been identified as markers with the best performance. Leukocytes showed a biphasic course with peaks on day 0 and day 11 after trauma, and patients with sepsis exhibited significantly higher leukocyte levels. Thrombocyte numbers showed a typical profile with initial thrombopenia and robust thrombocytosis in week 3 after trauma, ranging 2- to 3-fold above the upper normal value. 'Relative thrombocytopenia' was associated with multi-organ dysfunction, the development of sepsis, and mortality, the latter of which could be predicted within 3 days prior to the time point of death. SPHK1 expression at the day of admission indicated mortality with excellent performance. C5-expression on day 1 after trauma correlated with an increased risk for the development of nosocomial infections during the later course, while HP was found to be a marker for the development of sepsis. CONCLUSIONS: The combination of clinical and transcriptomic markers improves the prognostic performance and may represent a useful tool for individual risk stratification in trauma patients.

Energy-sensing factors coactivator peroxisome proliferator-activated receptor γ coactivator 1-α (PGC-1α) and AMP-activated protein kinase control expression of inflammatory mediators in liver: induction of interleukin 1 receptor antagonist.

Obesity and insulin resistance are associated with chronic, low grade inflammation. Moreover, regulation of energy metabolism and immunity are highly integrated. We hypothesized that energy-sensitive coactivator peroxisome proliferator-activated receptor γ coactivator 1-α (PGC-1α) and AMP-activated protein kinase (AMPK) may modulate inflammatory gene expression in liver. Microarray analysis revealed that PGC-1α up-regulated expression of several cytokines and cytokine receptors, including interleukin 15 receptor α (IL15Rα) and, even more importantly, anti-inflammatory interleukin 1 receptor antagonist (IL1Rn). Overexpression of PGC-1α and induction of PGC-1α by fasting, physical exercise, glucagon, or cAMP was associated with increased IL1Rn mRNA and protein expression in hepatocytes. Knockdown of PGC-1α by siRNA down-regulated cAMP-induced expression of IL1Rn in mouse hepatocytes. Furthermore, knockdown of peroxisome proliferator-activated receptor α (PPARα) attenuated IL1Rn induction by PGC-1α. Overexpression of PGC-1α, at least partially through IL1Rn, suppressed interleukin 1ß-induced expression of acute phase proteins, C-reactive protein, and haptoglobin. Fasting and exercise also induced IL15Rα expression, whereas glucagon and cAMP resulted in reduction in IL15Rα mRNA levels. Finally, AMPK activator metformin and adenoviral overexpression of AMPK up-regulated IL1Rn and down-regulated IL15Rα in primary hepatocytes. We conclude that PGC-1α and AMPK alter inflammatory gene expression in liver and thus integrate energy homeostasis and inflammation. Induction of IL1Rn by PGC-1α and AMPK may be involved in the beneficial effects of exercise and caloric restriction and putative anti-inflammatory effects of metformin.

Association of acute phase protein-haptoglobin, and epithelial-mesenchymal transition in buccal cancer: a preliminary report.

BACKGROUND: The aim of this study was to determine the influence of inflammation on acute phase protein and epithelial-mesenchymal transition (EMT) in buccal cancer. METHODS: Western blotting was carried out to investigate the expression of haptoglobin and epithelial-mesenchymal transition in oral cancer cell lines with or without IL-6 stimulation. We studied patients with buccal cancer patients without distant metastasis at diagnosis. Correlation between cellular haptoglobin, EMT, and clinical characteristics of buccal cancer was analyzed to assess the prognostic value of cellular haptoglobin level and EMT. The relationship of haptoglobin, and EMT expression with survival was assessed using Cox proportional hazard models. RESULTS: Western blotting analysis showed that increased haptoglobin protein was associated with overexpression of vimentin. Under IL-6 stimulation, overexpression of haptoglobin, EMT-associated motile phenotype was noted in OC2 cell lines. Overexpression of haptoglobin was also associated with an increased risk for locoregional recurrence [hazard ratio (HR) 1.04; p=0.011] after adjusting for age, gender, disease site, stage, and treatment modality. CONCLUSIONS: Increased cellular expression of haptoglobin is associated with EMT in oral cancer cell lines and this phenomenon could be exaggerated with IL-6. Cellular expression of haptoglobin is related to locoregional recurrence rate in buccal cancer patients.

Hypoxia-inducible factor-1alpha enhances haptoglobin gene expression by improving binding of STAT3 to the promoter.

Haptoglobin (Hp) is known to play a role in angiogenesis as well as in anti-inflammation. STAT3 is a major transcription factor for expression of human Hp. We investigated whether hypoxia-inducible factor-1α (HIF-1α), a key mediator of angiogenesis, participates in Hp gene expression. HIF-1α overexpression by gene transfection or hypoxia augmented Hp transcription in HepG2 human hepatoma cells. Conversely, knockdown of HIF-1α by specific siRNA transfection diminished Hp expression, although the level of STAT3 phosphorylation remained unchanged. A luciferase reporter assay using mutant Hp promoters demonstrated that two adjacent DNA elements, a STAT3-binding element (SBE) and a cAMP-response element (CRE)-like site in human Hp promoter -120/-97, were required for HIF-1α-stimulated transactivation of the Hp gene. HIF-1α, STAT3, and p300/CBP were simultaneously bound to the SBE/CRE as a complex form. When HIF-1α was knocked down, STAT3 binding to the SBE in the Hp promoter was attenuated. Our findings suggest that HIF-1α assists STAT3 in strong binding to the proximal SBE in the Hp promoter. The CRE-like site located near the SBE may contribute to the formation of a stable complex of STAT3, HIF-1α, and p300/CBP, which leads to maximum transcription of the Hp gene.

MicroRNA-18a enhances the interleukin-6-mediated production of the acute-phase proteins fibrinogen and haptoglobin in human hepatocytes.

The acute-phase response is an inflammatory process triggered mainly by the cytokine IL-6. Signaling of IL-6 is transduced by activation of STAT3 (signal transducer and activator of transcription 3), which rapidly induces the production of acute-phase proteins such as haptoglobin and fibrinogen. Another target of the IL-6/STAT3 signal transduction pathway is the microRNA cluster miR-17/92. Here, we investigated the interplay of miR-17/92 and STAT3 signaling and its impact on the acute-phase response in primary human hepatocytes and hepatoma (HepG2) cells. Employing a reporter gene system consisting of STAT3-sensitive promoter sequences, we show that the miR-17/92 cluster member miR-18a enhanced the transcriptional activity of STAT3. IL-6 stimulation experiments in miR-18a-overexpressing hepatocytes and HepG2 cells revealed an augmented acute-phase response indicated by increased expression and secretion of haptoglobin and fibrinogen. This effect was due, at least in part, to repression of PIAS3 (protein inhibitor of activated STAT, 3), a repressor of STAT3 activity, which we identified as a novel direct target of miR-18a. Finally, we demonstrate that the expression of miR-17/92 in primary hepatocytes and HepG2 cells is modulated by IL-6. Our data reveal, for the first time, a microRNA-mediated positive feedback loop of IL-6 signal transduction leading to an enhanced acute-phase response in human hepatocytes.

Involvement of STAT3-regulated hepatic soluble factors in attenuation of stellate cell activity and liver fibrogenesis in mice.

Glycoprotein 130 (gp130)/signal transducer and activator of transcription 3 (STAT3) signaling in hepatocytes controls a variety of physiological and pathological processes including liver regeneration, apoptosis resistance and metabolism. Recent research has shed light on the importance of acute phase proteins (APPs) regulated by hepatic gp130/STAT3 in host defense through suppression of innate immune responses during systemic inflammation. To examine whether these STAT3-regulated soluble factors directly affect liver fibrogenic responses during liver injury, hepatocyte-specific STAT3 knockout (L-STAT3 KO) mice and control littermates were subjected to bile duct ligation (BDL) and examined 10 days later. In contrast to controls, L-STAT3 KO mice failed to produce APPs, such as serum amyloid A and haptoglobin, after BDL. Whereas L-STAT3 KO mice displayed similar levels of cholestasis, inflammatory cell infiltration and regeneration in the liver, they developed exacerbated liver injury and fibrosis with significant increases in expression of alpha-smooth muscle actin and type I collagen genes. In vitro experiments revealed that attenuated expression of APPs in primary hepatocytes isolated from L-STAT3 KO mice with IL-6 exposure, compared to wild-type hepatocytes. The cultured supernatant from IL-6-treated wild-type hepatocytes inhibited expression of alpha-smooth muscle actin and type I collagen genes in activated hepatic stellate cells (HSCs), whereas this did not occur with the supernatant from IL-6-treated knockout hepatocytes or with control medium. In conclusion, the absence of STAT3 in hepatocytes leads to exacerbation of liver fibrosis during cholestasis. Soluble factors released from hepatocytes, dependent on STAT3, collectively play a protective role in liver fibrogenesis through an inhibitory effect on activated HSCs.

The function of the soluble interleukin 6 (IL-6) receptor in vivo: sensitization of human soluble IL-6 receptor transgenic mice towards IL-6 and prolongation of the plasma half-life of IL-6.

Interleukin 6 (IL-6) is considered an important mediator of acute inflammatory responses. Moreover, IL-6 functions as a differentiation and growth factor of hematopoietic precursor cells, B cells, T cells, keratinocytes, neuronal cells, osteoclasts, and endothelial cells. IL-6 exhibits its action via a receptor complex consisting of a specific IL-6 receptor (IL-6R) and a signal transducing subunit (gp130). Soluble forms of both receptor components are generated by shedding and are found in patients with various diseases such as acquired immune deficiency syndrome, rheumatoid arthritis, and others. The function of the soluble (s)IL-6R in vivo is unknown. Since human (h)IL-6 acts on human and murine target cells, but murine IL-6 on murine cells only, we constructed transgenic mice expressing the hsIL-6R. We report here that in the presence of hsIL-6R, mice are hypersensitized towards hIL-6, mounting an acute phase protein gene induction at significantly lower IL-6 dosages compared to control animals. Furthermore, in hsIL-6R transgenic mice, the detected acute phase response persists for a longer period of time. The IL-6/IL-6R complex prolongs markedly the Il-6 plasma half-life. Our results reinforce the role of the hsIL-6R as an agonistic protein, help to understand the function of the hsIL-6R in vivo, and highlight the significance of the receptor in the induction of the acute phase response.

Inflammatory cytokines differentially up-regulate human endometrial haptoglobin production in women with endometriosis.

BACKGROUND: Evidence suggests that eutopic endometrium from women with endometriosis (US-E) has intrinsic functional anomalies compared with women without endometriosis (US-C). We hypothesized that differences in endometrial haptoglobin (eHp) mRNA and protein levels exist between eutopic endometrium from US-E and US-C and that inflammatory mediators may be involved. METHODS: Endometrial stromal cells and tissue explants from US-E (n = 18) and US-C (n = 18) were cultured (24 h/48 h for cells/explants) with interleukin (IL)-1alpha, -1beta, -6, -8 or tumor necrosis factor-alpha (TNF-alpha) at 0-100 ng/ml. eHp protein in media and mRNA levels were quantified by enzyme-linked immunosorbent assay and quantitative PCR. RESULTS: In eutopic endometrial stromal cells from US-E, IL-1beta, IL-6 and TNF-alpha (10 ng/ml) increased eHp mRNA levels (P = 0.002, P < 0.001 and P < 0.001, respectively) and eHp protein (P = 0.023, 0.031 and 0.006, respectively) versus control. In endometrial tissues from US-E, IL-1beta, IL-6 and TNF-alpha increased eHp mRNA (P < 0.001, P = 0.017 and P < 0.001, respectively) and eHp protein (P < 0.001, P = 0.007 and 0.039, respectively) versus control. IL-1alpha and IL-8 had small or no effects on isolated endometrial cells or tissues. In US-C, IL-1beta, IL-8 and TNF-alpha each reduced eHp mRNA in endometrial stromal cells (all P < 0.001) versus control; IL-1alpha and IL-6 had no effect. eHp mRNA increased in endometrial tissues from US-C in response to IL-1beta (P = 0.008), IL-6 (P = 0.015) and TNF-alpha (P = 0.031) versus control; IL-1alpha or IL-8 had no effect. CONCLUSIONS: Endometrium from US-E differentially responds to specific inflammatory cytokines by production of eHp. We propose that up-regulation of endometrial eHp by inflammatory mediators disrupts normal endometrial function and may facilitate the pathogenesis of endometriosis.

Time-dependent mRNA expression of selected pro-inflammatory factors in the endometrium of primiparous cows postpartum.

BACKGROUND: Inflammatory processes and infections of the uterine wall must be accepted as a physiological event in dairy cows after calving. This might result in clinical or subclinical endometritis which is assumed to impair reproductive performance in the current lactation. Several cytokines and acute phase proteins have been discussed as local and systemic mediators of these inflammatory processes. The aim of the present study was to investigate the endometrial mRNA expression of the chemokine CXC ligand 5 (CXCL5), interleukin 1ß (IL1B), IL6, IL8, tumour necrosis factor alpha (TNF), prostaglandin-endoperoxide synthase 2 (PTGS2) and haptoglobin (HP) in the postpartum period. METHODS: Endometrial samples were obtained from primiparous cows (n = 5) on days 10, 17, 24, 31, 38 and 45 postpartum (pp) using the cytobrush technique. Cytological smears were prepared from cytobrush samples to determine the proportion of polymorphonuclear neutrophils (PMN). Total RNA was extracted from endometrial samples, and real-time RT-PCR was performed. RESULTS: A time-dependent mRNA expression of the investigated factors was found for the course of the postpartum period. In detail, a significantly higher expression of these factors was observed on day 17 pp compared to day 31 pp. Furthermore, the proportion of PMN peaked between days 10-24 pp and decreased thereafter to low percentages (< 5%) on day 31 pp and thereafter. In addition, CXCL5, IL1B, IL8 and HP mRNA expression correlated significantly with the proportion of PMN (P < 0.05). A significantly higher CXCL5, IL1B, IL6, IL8, PTGS2 and TNF mRNA content was observed in samples from cows with an inflamed endometrium compared with samples from cows with a healthy endometrium (P < 0.05). CONCLUSIONS: These results show that inflammatory cytokines and acute phase proteins are expressed in the bovine endometrium in a time-related manner during the postpartum period, with a significant expression peak on day 17 pp as a possible mucosal immune response in the uterus. The evaluation of the expression patterns of such candidate genes may reveal more information than only determining the percentage of PMN to judge the severity of an inflammation.

Serum proteome of patients with systemic sclerosis: molecular analysis of expression and prevalence of haptoglobin alpha chain isoforms.

Haptoglobin (Hpt) is an acute phase protein characterized by three major phenotypes (Hpt 1-1, Hpt 2-1 and Hpt 2-2). The Hpt 2-2 phenotype is associated with increased prevalence of various systemic diseases, including autoimmune disorders. Moreover, the Hpt 2-2 phenotype induces a shift from Th1 to Th2 response and increases fibrotic processes. On this basis, we performed serum proteomic analysis of patients with Systemic Sclerosis (SSc), a connective tissue disorder associated with Th2-type immune response and characterized by interstitial and perivascular fibrosis due to different factors (including genetic, environmental, immunological and microchimeric factors). Serum of 23 SSc outpatients patients (4 males, 19 females, mean age 54+-5.3 years) diagnosed according to the American Rheumatism Association (ARA) criteria, were considered for the proteomic analysis and compared to serum of 21 control subjects. Serum depleted of HAP was analyzed by 2-DE, and Hpt chain spots were identified by WB. The expression frequency of each Hpt α chain in SSc patients and controls was compared and quantitative analysis of spot expression (percent Vol) was performed. Above all,, our study amplifies the limited data in the literature on proteomic analysis in SSc, also confirming previous data that revealed a significant increase of haptoglobin type 2-2 and a concomitant decrease of the 1-1 phenotype in SSc patients. Moreover, our results demonstrate that c spots are more prevalent in SSc patients than in controls (91.3% vs 55.5%, p<0.05), while the expression frequency of a and b spots does not change. In patients Hpt 2-1 or Hpt 1-1 e spot is less abundant. According to our results, the c and e spots can be considered markers for SSc and thus be of use for the early diagnosis of connective tissue disorders and in establishing appropriate treatment.

Regulation of mouse haptoglobin synthesis.

A cloned line of mouse hepatoma cells (Hepa-1) responded to treatment with dexamethasone by a 30-80-fold increase in synthesis and secretion of functional haptoglobin. Under the same conditions, the production of albumin was only slightly elevated whereas that of alpha 1-fetoprotein was reduced by 50%. The hormone concentration for half-maximal stimulation of haptoglobin synthesis was between 1 and 2 X 10(-8) M. The time course of induction is characteristic for a glucocorticoid-regulated protein. Cell-free translation of RNA indicated an increase in the amount of functional haptoglobin mRNA that can account for the change in the protein production. To correlate our findings on Hepa-1 cells with those on nontransformed liver cells, we tested the hormonal response of isolated hepatocytes in tissue culture. Haptoglobin was first synthesized and secreted by hepatocytes from 17-19-d-old fetuses. But neither prenatal nor adult hepatocytes showed a dexamethasone-dependent increase in haptoglobin synthesis. However, when several independent clones of hybrid cells formed from adult mouse hepatocytes and rat hepatoma cells were treated with dexamethasone, the synthesis of mouse haptoglobin was in all cases elevated. It appears that haptoglobin expression in mouse liver cells is potentially sensitive to glucocorticoids, but this modulation is manifested only in transformed cells and their derivatives.

Synthesis and regulation of acute phase plasma proteins in primary cultures of mouse hepatocytes.

Adult mouse hepatocytes respond in vivo to experimentally induced acute inflammation by an increased synthesis and secretion of alpha 1-acid glycoprotein, haptoglobin, hemopexin, and serum amyloid A. Concurrently, the production of albumin and apolipoprotein A-1 is reduced. To define possible mediators of this response and to study their action in tissue culture, we established primary cultures of hepatocytes. Various hormones and factors that have been proposed to regulate the hepatic acute phase reaction were tested for their ability to modulate the expression of plasma proteins in these cells. Acute phase plasma and conditioned medium from activated monocytes influenced the production of most acute phase plasma proteins, and the regulation appears to occur at the level of functional mRNA. Purified hormones produced a significant anabolic response in only a few cases: dexamethasone was found to be effective in maintaining differentiated expression of the cells; and glucagon produced a specific inhibition of haptoglobin synthesis. When cells were treated with a combination of conditioned monocyte medium and dexamethasone, secretion of proteins was markedly reduced. The carbohydrate moieties of all plasma glycoproteins were incompletely modified, apparently as a result of decreased intracellular transport of newly synthesized plasma proteins. Although primary hepatocytes were not phenotypically stable in tissue culture, the cells nevertheless retained a broad response spectrum to exogenous signals. We propose this as a useful system to study the production of plasma proteins and thereby pinpoint the nature and activity of effectors mediating the hepatic acute phase reaction.

IL-6-induced homodimerization of gp130 and associated activation of a tyrosine kinase.

The biological functions of interleukin-6 (IL-6) are mediated through a signal-transducing component of the IL-6 receptor, gp130, which is associated with the ligand-occupied IL-6 receptor (IL-6R) protein. Binding of IL-6 to IL-6R induced disulfide-linked homodimerization of gp130. Tyrosine kinase activity was associated with dimerized but not monomeric gp130 protein. Substitution of serine for proline residues 656 and 658 in the cytoplasmic motif abolished tyrosine kinase activation and cellular responses but not homodimerization of gp130. The IL-6-induced gp130 homodimer appears to be similar in function to the heterodimer formed between the leukemia inhibitory factor (LIF) receptor (LIFR) and gp130 in response to the LIF or ciliary neurotrophic factor (CNTF). Thus, a general first step in IL-6-related cytokine signaling may be the dimerization of signal-transducing molecules and activation of associated tyrosine kinases.

Haptoglobin expression in human colorectal cancer.

Aims and experimental design. The acute-phase protein haptoglobin (Hp) has been recently detected in colorectal cancer (CRC) tissue, where its expression correlates with metastasis. Recently, we identified Hp as a CDw75 antigen-expressing protein in colorectal tissue. To deepen the knowledge of this protein in CRC, we studied the expression of Hp in healthy and tumour tissue specimens from 62 CRC patients by immunohistochemistry and Western blotting, as well as in the Caco-2 and HT-29 CRC cell lines by quantitative PCR, immunofluorescence microscopy and flow cytometry. Results and discussion. Hp immuno-positive staining was absent in the 18 healthy colorectal specimens analysed, whereas it was observed in 24% (15/62) of the tumour specimens as cytoplasmic granules within cancer cells. Furthermore, Hp expression in CRC was associated with Dukes' stage and the presence of metastasis in our population of study. In vitro cultured Caco-2 and HT-29 cells expressed mRNA for Hp and the protein was detected at the cell surface. Conclusions. This study confirms the expression of Hp in CRC, both in vivo and in vitro, and provides further evidence of its association with disease progression and metastasis.

2-D DIGE and MS/MS analysis of protein serum expression in rats housed in concrete and clay cages in winter.

In a previous study, we examined the physiological responses of male Sprague-Dawley rats over a 4-week exposure to concrete and clay cages. No general toxicological changes were observed in rats exposed to either of the two cage types in summer. Under winter conditions, however, various general toxicological effects were detected in rats housed in concrete cages, although rats housed in clay cages showed no such effects. The infrared thermographic examination indicated that skin temperature in the concrete-housed rats was abnormally low, but not so in the clay-housed rats. We examined proteomic changes in the serum of rats housed in winter in concrete and clay cages using two-dimensional differential in-gel electrophoresis and mass spectrometry/mass spectrometry. Five proteins were identified and quantitatively validated; all were cold stress-induced, acute phase proteins that were either up-regulated (haptoglobin) or down-regulated (alpha-1-inhibitor III, alpha-2u globulin, complement component 3, and vitamin D-binding protein) in the concrete-housed rats. These results suggest that the 4-week exposure to a concrete cage in winter elicited a typical systemic inflammatory reaction (i.e. acute phase response) in the exposed rats.

Predicting left ventricular remodeling after a first myocardial infarction by plasma proteome analysis.

Recent improvements in therapeutic strategies did not prevent left ventricular remodeling (LVR), which remains a common event (30%) after acute myocardial infarction (AMI). We report the use of a systematic approach, based on comparative proteomics, to select circulating biomarkers that may be associated with LVR. We selected 93 patients enrolled in a prospective study. These patients with anterior wall Q-wave AMI underwent echocardiographic follow-up at hospitalization, 3 months and 1 year after AMI. They were divided into three groups (no, low, or high remodeling). Plasma samples of these patients (day 5 of hospitalization) were processed and stored at -80 degrees C within 2 h and analyzed using SELDI-TOF protein chip technology. This systematic approach allowed to select candidate proteins modulated by LVR: post-translational variants of alpha1-chain of haptoglobin (Hpalpha1) corresponding to m/z 9493, 9565, and 9623, which were more elevated in remodeling patients. The peak 9493 m/z was shown having a receiving-operating characteristic (ROC) value of 0.71 between non- and remodeling patients. SELDI-TOF approach may lead to the identification of circulating proteins associated with LVR. Whether these candidate proteins will help to identify patients who are at high risk of heart failure after AMI will have to be tested in future studies.

Regulation of C/EBPdelta-dependent transactivation by histone deacetylases in intestinal epithelial cells.

The C/EBPdelta transcription factor is involved in the positive regulation of the intestinal epithelial cell acute phase response. C/EBPdelta regulation by histone deacetylases (HDACs) during the course of inflammation remains to be determined. Our aim was to examine the effect of HDACs on C/EBPdelta-dependent regulation of haptoglobin, an acute phase protein induced in intestinal epithelial cells in response to pro-inflammatory cytokines. HDAC1, HDAC3, and HDAC4 were expressed in intestinal epithelial cells, as determined by Western blot. GST pull-down assays showed specific HDAC1 interactions with the transcriptional activation and the b-ZIP C/EBPdelta domains, while the co-repressor mSin3A interacts with the C-terminal domain. Immunoprecipitation assays confirmed the interaction between HDAC1 and the N-terminal C/EBPdelta amino acid 36-164 domain. HDAC1 overexpression decreased C/EBPdelta transcriptional activity of the haptoglobin promoter, as assessed by transient transfection and luciferase assays. Chromatin immunoprecipitation analysis showed a displacement of HDAC1 from the haptoglobin promoter in response to inflammatory stimuli and an increased acetylation of histone H3 and H4. HDAC1 silencing by shRNA expression increased both basal and IL-1beta-induced haptoglobin mRNA levels in epithelial intestinal cells. Our results suggest that interactions between C/EBPs and HDAC1 negatively regulate C/EBPdelta-dependent haptoglobin expression in intestinal epithelial cells.

Identification of an inducible factor secreted by pancreatic cancer cell lines that stimulates the production of fucosylated haptoglobin in hepatoma cells.

Fucosylation is one of the most important oligosaccharide modifications and is involved in cancer and inflammation. Recently, fucosylated haptoglobin was identified as a possible tumor marker for pancreatic cancer. The molecular mechanism underlying increases in fucosylated haptoglobin in sera of patients with pancreatic cancer seems to be complicated. Our previous study [N. Okuyama, Y. Ide, M. Nakano, T. Nakagawa, K. Yamanaka, K. Moriwaki, K. Murata, H. Ohigashi, S. Yokoyama, H. Eguchi, O. Ishikawa, T. Ito, M. Kato, A. Kasahara, S. Kawano, J. Gu, N. Taniguchi, E. Miyoshi, Fucosylated haptoglobin is a novel marker for pancreatic cancer: a detailed analysis of the oligosaccharide structure and a possible mechanism for fucosylation, Int. J. Cancer 118 (11) (2006) 2803-2808] demonstrated that pancreatic cancer cells secrete a factor, which induces the production of haptoglobin in hepatoma cells. In the present study, we found that interleukin 6 (IL6) expressed in pancreatic cancer is a factor that induces the haptoglobin production, using a neutralizing antibody for IL6. Real-time PCR analyses revealed the up-regulation of fucosylation regulatory genes after IL6 treatment, resulting increases in fucosylated haptoglobin being revealed by a lectin ELISA. This pathway could be one of the possible mechanisms underlying increases in haptoglobin in sera of patients with pancreatic cancer.