Interleukin-6 trans-signalling in chronic inflammation and cancer

IL-17 enhancement of the IL-6 signaling cascade in astrocytes

Astrocytes have important physiological roles in CNS homeostasis and serve as a bridge between the CNS and immune system. IL-17 and IL-6 are important in many CNS disorders characterized by neuroinflammation. We examined the role of IL-17 on the IL-6 signaling cascade in primary astrocytes. IL-17 functioned in a synergistic manner with IL-6 to induce IL-6 expression in astrocytes. The synergistic effect involved numerous signaling pathways including NF-kappaB, JNK MAPK, and p38 MAPK. The NF-kappaB pathway inhibitor BAY-11, JNK inhibitor JNKi II, and p38 inhibitor SB203580 suppressed the synergistic effect of IL-6 and IL-17 on IL-6 expression. IL-17 synergized with IL-6 to enhance the recruitment of activated NF-kappaB p65, c-Fos, c-Jun, and the histone acetyltransferases CREB-binding protein and p300 to the IL-6 promoter in vivo to induce IL-6 transcription. This was accompanied by enhanced acetylation of histones H3 and H4 on the IL-6 promoter. Moreover, we elucidated an important role for suppressor of cytokine signaling (SOCS) 3 in IL-17 enhancement of IL-6 signaling in astrocytes. SOCS3 small interfering RNA knockdown and SOCS3 deletion in astrocytes augmented the synergistic effect of IL-6 and IL-17 due to an enhancement of activation of the NF-kappaB and MAPK pathways. These results indicate that astrocytes can serve as a target of Th17 cells and IL-17 in the CNS, and SOCS3 participates in IL-17 functions in the CNS as a negative feedback regulator.

Interleukin-6 in bone metastasis and cancer progression

The bone and bone marrow are among the most frequent sites of cancer metastasis. It is estimated that 350,000 patients die with bone metastases annually in the United States. The ability of tumor cells to colonize the bone marrow and invade the bone is the result of close interactions between tumor cells and the bone marrow microenvironment. In this article, we review the contribution of interleukin-6 (IL-6) produced in the bone marrow microenvironment to bone metastasis. This cytokine has a strong pro-tumorigenic activity due to its multiple effects on bone metabolism, tumor cell proliferation and survival, angiogenesis, and inflammation. These effects are mediated by several signaling pathways, in particular the Janus kinase/signal transducer and transcription activator (JAK/STAT-3), Ras/mitogen activated protein kinase (MAPK), and phosphoinositol-3 kinase (PI3K)-protein kinase B/Akt (PkB/Akt), which are activated by IL-6 and amplified in the presence of soluble IL-6 receptor (sIL-6R). Supporting the role of IL-6 in human cancer is the observation of elevated serum levels of IL-6 and sIL-6R in patients with bone metastasis and their association with a poor clinical outcome. Over the last decade several large (monoclonal antibodies) and small (inhibitors of IL-6 mediated signaling) molecules that inhibit IL-6 activity in preclinical models have been developed. Several of these inhibitors are now undergoing phases I and II clinical trials, which will determine their inclusion in the list of effective targeted agents in the fight against cancer.

Novel IL31RA gene mutation and ancestral OSMR mutant allele in familial primary cutaneous amyloidosis

Primary cutaneous amyloidosis (PCA) is an itchy skin disorder associated with amyloid deposits in the superficial dermis. The disease is relatively common in Southeast Asia and South America. Autosomal dominant PCA has been mapped earlier to 5p13.1-q11.2 and two pathogenic missense mutations in the OSMR gene, which encodes the interleukin-6 family cytokine receptor oncostatin M receptor beta (OSMRbeta), were reported. Here, we investigated 29 Taiwanese pedigrees with PCA and found that 10 had heterozygous missense mutations in OSMR: p.D647V (one family), p.P694L (six families), and p.K697T (three families). The mutation p.P694L was associated with the same haplotype in five of six families and also detected in two sporadic cases of PCA. Of the other 19 pedigrees that lacked OSMR pathology, 8 mapped to the same locus on chromosome 5, which also contains the genes for 3 other interleukin-6 family cytokine receptors, including interleukin-31 receptor A (IL31RA), which can form a heterodimeric receptor with OSMRbeta through interleukin-31 signaling. In one family, we identified a point mutation in the IL31RA gene, c.1562C>T that results in a missense mutation, p.S521F, which is also sited within a fibronectin type III-like repeat domain as observed in the OSMR mutations. PCA is a genetically heterogeneous disorder but our study shows that it can be caused by mutations in two biologically associated cytokine receptor genes located on chromosome 5. The identification of OSMR and IL31RA gene pathology provides an explanation of the high prevalence of PCA in Taiwan as well as new insight into disease pathophysiology.

CLU "in and out": looking for a link

Cancer cells need to interact synergistically with their surrounding microenvironment to form a neoplasm and to progress further to colonize distant organs. The microenvironment can exert profound epigenetic effects on cells through cell-derived interactions between cells, or through cell-derived factors deposited into the microenvironment. Tumor progression implies immune-escaping and triggers several processes that synergistically induce a cooperation among transformed and stromal cells, that compete for space and resources such as oxygen and nutrients. Therefore, the extra cellular milieu and tissue microenvironment heterotypic interactions cooperate to promote tumor growth, angiogenesis, and cancer cell motility, through elevated secretion of pleiotropic cytokines and soluble factors. Clusterin (CLU), widely viewed as an enigmatic protein represents one of the numerous cellular factors sharing the intracellular information with the microenvironment and it has also a systemic diffusion, tightly joining the "In and the Out" of the cell with a still debated variety of antagonistic functions. The multiplicity of names for CLU is an indication of the complexity of the problem and could reflect, on one hand its multifunctionality, or alternatively could mask a commonality of function. The posited role for CLU, further supported as a cytoprotective prosurvival chaperone-like molecule, seems compelling, in contrast its tumor suppressor function, as a guide of the guardians of the genome (DNA-repair proteins Ku70/80, Bax cell death inducer), could really reflect the balanced expression of its different forms, most certainly depending on the intra- and extracellular microenvironment cross talk. The complicated balance of cytokines network and the regulation of CLU forms production in cancer and stromal cells undoubtedly represent a potential link among adaptative responses, genomic stability, and bystander effect after oxidative stresses and damage. This review focuses on the tumor-microenvironment interactions strictly involved in controlling local cancer growth, invasion, and distant metastases that play a decisive role in the regulation of CLU different forms expression and release. In addition, we focus on the pleiotropic action of the extracellular form of this protein, sCLU, that may play a crucial role in redirecting stromal changes, altering intercellular communications binding cell surface receptors and contributing to influence the secretion of chemokines in paracrine and autocrine fashion. Further elucidation of CLU functions inside and outside ("in and out") of cancer cell are warranted for a deeper understanding of the interplay between tumor and stroma, suggesting new therapeutic cotargeting strategies.

Clotting, immune system, and venous thrombosis in lung adenocarcinoma patients: a prospective study

Thrombosis is highly prevalent in cancer patients, being accepted as a bad prognosis marker. The importance of various mechanisms involved in the thrombophilic state of lung cancer patients is not well understood. In this prospective study, involving 109 unselected patients with lung adenocarcinoma, thrombosis was present in 24% of patients and affected survival in a bivariable model. However, in a multivariable evaluation, considering all the factors under study, only LAC and IgM anti-beta(2) GP I modified thrombosis risk, whereas in a Kaplan-Meyer regression model, thrombosis, IL-6, LAC, factor VIII, and IgM anti-beta(2) GP I interfered with patient's survival.

The role of aldosterone in mediating the dependence of angiotensin hypertension on IL-6

Knockout (KO) of IL-6 has been shown to attenuate ANG II hypertension, and mineralocorticoid receptors (MR) have been reported to contribute to the increase in IL-6 during acute ANG II infusion. This study determined whether that MR action is sustained with chronic ANG II infusion and whether it plays a role in mediating ANG II hypertension. ANG II infusion (90 ng/min) increased plasma IL-6 from 1.6 +/- 0.6 to 22.7 +/- 2.2 and 19.9 +/- 3.2 pg/ml on days 7 and 14, respectively, and chronic MR blockade with spironolactone attenuated that only at day 7 (7.2 +/- 2.2 pg/ml). ANG II increased MAP (19 h/day with telemetry) approximately 40 mmHg, but in ANG II+spironolactone mice (25 or 50 mg*kg(-1)*day(-1)), mean arterial pressure (MAP) was not significantly different despite a tendency for lower pressure the first 6 days. To isolate further the mineralocorticoid link to IL-6 and blood pressure, DOCA-salt hypertension was induced in IL-6 KO and wild-type (WT) mice. Plasma IL-6 increased from 4.1 +/- 1.7 to 34.5 +/- 7.0 pg/ml by day 7 of DOCA treatment in the WT mice but was back to control levels by day 14. An IL-6 bioassay using the murine B9, B-cell hybridoma cell line demonstrated that plasma IL-6 measurements reflected actual IL-6 bioactivity. The hypertension was not different and virtually superimposable in WT vs. IL-6 KO mice, averaging 145 +/- 2 and 144 +/- 3 mmHg, respectively. Both experiments confirm chronic stimulation of IL-6 by mineralocorticoids but show that it is transient. In addition, IL-6 was not required for mineralocorticoid hypertension. This suggests that aldosterone contributes to the increase in plasma IL-6 in the early stage of ANG II hypertension but that the blood pressure actions of IL-6 in that model are linked most likely to ANG II rather than aldosterone.

Recent advances in neutralizing the IL-6 pathway in arthritis

Recent advances in understanding the mechanism(s) of how IL-6 trans-signaling regulates immune cell function and promotes inflammation in autoimmune arthritis are critically reviewed. Serum and/or synovial fluid (SF) IL-6 is markedly elevated in adult and juvenile rheumatoid arthritis (RA), psoriatic arthritis (PsA), ankylosing spondylitis (AS) and osteoarthritis (OA). IL-6, in concert with IL-17, determines the fate of CD4⁺ lymphocytes and therefore TH₁₇ cell differentiation. IL-6 also plays a critical role in modulating B-lymphocyte activity. The recognition that IL-6 trans-signaling regulates inflammation resulted in the development of tocilizumab, a fully humanized monoclonal antibody that neutralizes the biological activity of the IL-6-receptor (IL-6R). Significant clinical benefit was demonstrated as well as reduced serum IL-6 levels with suppression of X-ray progression of disease in several clinical trials in which juvenile or adult RA patients were treated with tocilizumab monotherapy or tocilizumab plus methotrexate. However, levels of serum and/or SF IL-6 cytokine protein superfamily members, adiponectin, oncostatin M, pre-B-cell colony enhancing factor/visfatin and leukemia inhibitory factor are also elevated in RA. Additional studies will be required to determine if anti-IL-6 trans-signaling inhibition strategies with tocilizumab or recombinant soluble IL-6R reduce the level of these cytokines.

Influences of interferon-gamma on cell proliferation and interleukin-6 production in Down syndrome derived fibroblasts

OBJECTIVE

Down syndrome, a frequently encountered genetic disorder, is usually associated with medical problems related to infectious disease, such as periodontal diseases and prolonged wound healing. Although affected individuals are considered to have clinical problems related to high interferon (IFN) sensitivity, the molecular mechanisms of IFN activities are not completely understood.

DESIGN

Down syndrome derived fibroblasts, Detroit 539 (D1) and Hs 52.Sk (D2) cells, were used. To analyse the expressions of interferon (IFN) receptors and downstream of IFN-gamma, western blotting was performed. Cell proliferation was determined by counting cells following trypan blue staining. Media levels of IL-1beta, TNF-alpha, and IL-6 were quantified using ELISA.

RESULTS

IFN-gamma receptor 2 and IFN-alpha receptor 1, but not IFN-gamma receptor 1, were highly expressed in D1 and D2 cells, as compared to the control fibroblast cells. Cell proliferation by D1 and D2 cells was lower than that by the control fibroblasts, further, IFN-gamma had a greater effect to inhibit cell proliferation by D1 and D2 cells. In addition, IFN-gamma treatment increased the phosphorylation of STAT1 and MAPK in D1 cells as compared to normal fibroblasts. Also, the presence of exogenous IFN-gamma in the growth medium significantly induced IL-6, but not IL-1beta or TNF-alpha, in D1 and D2 cells.

CONCLUSION

Taken together, our results are consistent with hypersensitive reactions to IFN-gamma seen in patients with Down syndrome and may provide useful information to elucidate the mechanisms of IFN-gamma activities in those individuals.

MAIL regulates human monocyte IL-6 production

IL-6 is a pleiotropic cytokine implicated in the pathogenesis of disorders such as sepsis and cancer. We noted that human monocytes are excellent producers of IL-6 as compared with monocyte-derived macrophages. Because macrophages from molecule containing ankyrin repeats induced by LPS (MAIL) knockout animals have suppressed IL-6 production, we hypothesized that regulation of MAIL is key to IL-6 production in humans and may explain the differences between human monocytes and macrophages. To test this hypothesis fresh human monocytes and monocyte-derived macrophages were compared for MAIL expression in response to LPS. LPS-induced monocyte MAIL expression was highly inducible and transient. Importantly for our hypothesis MAIL protein expression was suppressed during differentiation of monocytes to macrophages. Of note, the human MAIL protein detected was the 80 kDa MAIL-L form and human MAIL showed nuclear localization. Human MAIL-L bound to p50 subunit of the NF-kappaB and increased IL-6 luciferase promoter activity in a cEBPbeta, NF-kappaB, and AP-1-dependent fashion. Like the differences in MAIL induction, monocytes produced 6-fold more IL-6 compared with macrophages (81.7 +/- 29.7 vs 12.6 +/- 6.8 ng/ml). Furthermore, suppression of MAIL by small interfering RNA decreased the production of IL-6 significantly in both THP-1 cells and in primary monocytes. Costimulation of monocytes with LPS and muramyl dipeptide induced an enhanced IL-6 response that was suppressed by siMAIL. Our data suggests that MAIL is a key regulator of IL-6 production in human monocytes and plays an important role in both TLR and NOD-like receptor ligand induced inflammation.

Induction of the interleukin 6/ signal transducer and activator of transcription pathway in the lungs of mice sub-chronically exposed to mainstream tobacco smoke

Background

Tobacco smoking is associated with lung cancer and other respiratory diseases. However, little is known about the global molecular changes that precede the appearance of clinically detectable symptoms. In this study, the effects of mainstream tobacco smoke (MTS) on global transcription in the mouse lung were investigated.

Methods

Male C57B1/CBA mice were exposed to MTS from two cigarettes daily, 5 days/week for 6 or 12 weeks. Mice were sacrificed immediately, or 6 weeks following the last cigarette. High density DNA microarrays were used to characterize global gene expression changes in whole lung. Microarray results were validated by Quantitative real-time RT-PCR. Further analysis of protein synthesis and function was carried out for a select set of genes by ELISA and Western blotting.

Results

Globally, seventy nine genes were significantly differentially expressed following the exposure to MTS. These genes were associated with a number of biological processes including xenobiotic metabolism, redox balance, oxidative stress and inflammation. There was no differential gene expression in mice exposed to smoke and sampled 6 weeks following the last cigarette. Moreover, cluster analysis demonstrated that these samples clustered alongside their respective controls. We observed simultaneous up-regulation of interleukin 6 (IL-6) and its antagonist, suppressor of cytokine signalling (SOCS3) mRNA following 12 weeks of MTS exposure. Analysis by ELISA and Western blotting revealed a concomitant increase in total IL-6 antigen levels and its downstream targets, including phosphorylated signal transducer and activator of transcription 3 (Stat3), basal cell-lymphoma extra large (BCL-XL) and myeloid cell leukemia 1 (MCL-1) protein, in total lung tissue extracts. However, in contrast to gene expression, a subtle decrease in total SOCS3 protein was observed after 12 weeks of MTS exposure.

Conclusion

Global transcriptional analysis identified a set of genes responding to MTS exposure in mouse lung. These genes returned to basal levels following smoking cessation, providing evidence to support the benefits of smoking cessation. Detailed analyses were undertaken for IL-6 and its associated pathways. Our results provide further insight into the role of these pathways in lung injury and inflammation induced by MTS.

High weight differences between donor and recipient affect early kidney graft function--a role for enhanced IL-6 signaling

The frequency of delayed function of kidney transplants varies greatly and is associated with quality of graft, donor age and the duration of cold ischemia time. Furthermore, body weight differences between donor and recipient can affect primary graft function, but the underlying mechanism is poorly understood. We transplanted kidney grafts from commensurate body weight (L-WD) or reduced body weight (H-WD) donor rats into syngeneic or allogeneic recipients. Twenty-four hours posttransplantation, serum creatinine levels in H-WD recipients were significantly higher compared to L-WD recipients indicating impaired primary graft function. This was accompanied by upregulation of IL-6 transcription and increased tubular destruction in grafts from H-WD recipients. Using DNA microarray analysis, we detected decreased expression of genes associated with kidney function and an upregulation of other genes such as Cyp3a13, FosL and Trib3. A single application of IL-6 into L-WD recipients is sufficient to impair primary graft function and cause tubular damage, whereas immediate neutralization of IL-6 receptor signaling in H-WD recipients rescued primary graft function with well-preserved kidney graft architecture and a normalized gene expression profile. These findings have strong clinical implication as anti-IL6R treatment of patients receiving grafts from lower-weight donors could be used to improve primary graft function.

The weight of interleukin-6 in B cell-related autoimmune disorders

Interleukin (IL)-6 is a prevailing factor of polyclonal B-cell activation of B cells, and thereby of their tolerance breach. Its receptor (R) complex consists of a transducing unit, and a membrane-bound or soluble protein. Many activities ascribed to this cytokine are generated by the soluble IL-6R. Evidence has however been gleaned in autoimmune diseases that the system is instrumental in rheumatoid arthritis (RA), Sjögren's syndrome and systemic lupus erythematosus (SLE). To gain insight into the understanding of the mechanisms behind these observations, a prime example is the recombination-activating gene (Rag) machinery in B lymphocytes. It is interesting that the expression of Rags is favored by IL-6, and repressed by anti-IL-6R antibody (Ab) in RA and SLE. Not surprisingly, clinical benefits are reported in the treatment of autoimmune disorders with anti-IL-6R Ab, and other perspectives about to be open in biotherapy.

The response of circulating levels of the interleukin-6/interleukin-6 receptor complex to exercise in young men

The formation of an interleukin-6/IL-6 receptor (IL-6/IL-6R) complex increases the biological activity and half-life of IL-6, with its response to exercise currently unknown. The aim of the present study was to determine the response of circulating levels of the IL-6/IL-6R complex to exercise. Nine healthy male participants performed 1h of cycling exercise at a workload required to elicit 90% lactate threshold. Venous blood samples were taken at rest, immediately post-exercise and after 1.5 h rest. Hemoglobin concentration and hematocrit were measured to estimate changes in plasma volume during exercise. The concentrations of IL-6, sIL-6R and the IL-6/IL-6R complex were measured via ELISA and corrected for changes in plasma volume. A single bout of acute exercise resulted in a 5-fold increase (P<0.05) in IL-6 and a 1.2-fold increase (P<0.05) in sIL-6R immediately after exercise. These returned to baseline at 1.5 h after the cessation of exercise. There was a 2.1-fold increase (P<0.05) in the levels of the IL-6/IL-6R complex post-exercise with levels remaining 1.8 times elevated (P<0.05) after 1.5 h rest. The present study has demonstrated, for the first time, that circulating levels of the IL-6/IL-6R complex are increased in response to acute exercise in young males.

Clinical significances of preoperative serum interleukin-6 and C-reactive protein level in operable gastric cancer

BACKGROUND

The interleukin-6 (IL-6) pathway is one of the mechanisms that link inflammation and angiogenesis to malignancy. Because the C-reactive protein (CRP) is a representative marker for inflammation, CRP has recently been associated with the progression of disease in many cancer types. The principal objective of this study was to determine the preoperative serum levels of IL-6 and CRP in gastric carcinoma, and to correlate them with disease status and prognosis.

METHODS

A total of 115 patients who underwent gastrectomy were enrolled in this study. Serum levels of IL-6 were assessed via Enzyme-Linked Immuno-Sorbent Assay (ELISA), and CRP was measured via immunoturbidimetry. Histological findings included tumor size, depth of tumor invasion, lymph node (LN) metastasis, and TNM stage (6th AJCC Stage Groupings: The staging systems; Primary tumor, regional LN, metastasis).

RESULTS

Increases in cancer invasion and staging are generally associated with increases in preoperative serum IL-6 levels. IL-6 and CRP levels were correlated with invasion depth (P < 0.001, P = 0.001), LN metastasis (P < 0.001, P = 0.024) and TNM stage (P < 0.001, P < 0.001). The presence of peritoneal seeding metastasis is associated with IL-6 levels (P = 0.012). When we established the cutoff value for IL-6 level (6.77 pg/dL) by ROC curve, we noted significant differences in time to progression (TTP; P < 0.001) and overall survival (OS; P = 0.010). However, CRP evidenced no significance with regard to patients' TTP and OS levels. Serum IL-6 levels were correlated positively with CRP levels (r2 = 0.049, P = 0.018).

CONCLUSION

Preoperative serum IL-6 and CRP levels might be markers of tumor invasion, LN metastasis, and TNM stage. Preoperative high IL-6 levels were proposed as a poor prognostic factor for disease recurrence and overall survival in patients with gastric cancers.

Plasma IL-6, its soluble receptors and F2-isoprostanes at rest and during exercise in chronic fatigue syndrome

The aim of the current study was to investigate the levels of interleukin-6 (IL-6), its soluble receptors (sIL-6R and sgp130) and F(2)-isoprostanes, at rest and during exercise, in patients with chronic fatigue syndrome (CFS). Six male CFS patients and six healthy controls performed an incremental exercise test to exhaustion and a submaximal exercise bout to exhaustion. Blood samples taken in the submaximal test at rest, immediately post-exercise and 24 h post-exercise were analyzed for IL-6, sIL-6R, sgp130 and F(2)-isoprostanes. A further 33 CFS and 33 healthy control participants gave a resting blood sample for IL-6 and sIL-6R measurement. During the incremental exercise test only power output at the lactate threshold was lower (P<0.05) in the CFS group. F(2)-isoprostanes were higher (P<0.05) in CFS patients at rest and this difference persisted immediately and 24 h post-exercise. The exercise study found no differences in IL-6, sIL-6R or sgp130 at any time point between groups. In the larger resting group, there were no differences in IL-6 and sIL-6R between CFS and control groups. This investigation has demonstrated that patients with CFS do not have altered plasma levels of IL-6, sIL-6R or sgp130 either at rest or following exercise. F(2)-isoprostanes, however, were consistently higher in CFS patients.

Immunomodulatory effects of Abnormal Savda Munsiq, a traditional Uighur medicine, on the combined stress mice

OBJECTIVE

To investigate the immunomodulatory effects of ASMq, a herbal preparation used in Traditional Uighur Medicine, on the combined stress mice.

MATERIALS AND METHODS

The combined stress was induced on mice by application of the electric-foot shock in a cold-dry environment and three different doses of ASMq were orally administered to the animals for 14 days. The effect of ASMq on the immune apparatus weight index, lymphocytes proliferation, serum levels of the cytokines, immunoglobulins, hemolysin and NK cells as well as the phagocytic activity of the macrophages were evaluated.

RESULTS

Oral administration of ASMq was found to increase the thymus and spleen indices, lymphocytes proliferation induced by Con A and LPS, the percentage of CD4(+) in thymus, spleen and peripheral blood and restore the CD4(+)/CD8(+) ratio. The serum concentrations of INF-beta, IL-2, IL-6, IgG, NK cells and hemolysin were also increased. The macrophage phagocytic activity was also enhanced.

Glycine- and proline-rich glycoprotein regulates the balance between cell proliferation and apoptosis for ACF formation in 1,2-dimethylhydrazine-treated A/J mice

The objective of this study was to investigate the chemopreventive potentials of glycine- and proline-rich glycoprotein (SNL glycoprotein, 150-kDa) isolated from Solanum nigrum Linne on formation of colonic aberrant crypt foci (ACF) induced by 1,2-dimethylhydrazine (DMH, 20 mg/kg) in A/J mice. Administration of SNL glycoprotein inhibited phosphorylation of extracellular signal-regulated kinase (ERK), expression of colonic proliferating cell nuclear antigen (PCNA), and frequency of colonic ACF in DMH-stimulated mice colon carcinogenesis. In addition, SNL glycoprotein increased expression of cyclin-dependent kinase inhibitors (p21(WAF/Cip1) and p27(Kip1)), whereas reduced expression of precursor form of apoptosis-related proteins [pro-caspase-3 and pro-poly(ADP-ribose)polymerase (PARP)] in the mice. Interestingly, the results in this study revealed that SNL glycoprotein has suppressive effects on activity of nuclear factor-kappa B (NF-kappaB), whereas it has stimulatory effect on the expression of p53, accompanying inhibitory effects on expression of NF-kappaBp50, inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), interleukin (IL)-6, and tumor necrosis factor (TNF)-alpha in DMH-stimulated ACF formation. Also, SNL glycoprotein has inhibitory effects on the formation of thiobarbituric acid reactive substances (TBARS), on the production of inducible nitric oxide (NO), and on the release of lactate dehydrogenase (LDH) in the mice plasma. Collectively, our findings in this study suggest that SNL glycoprotein has chemopreventive activity via modulation of cell proliferation and apoptosis in DMH-treated A/J mice.

Cancer risk in hospitalised asthma patients

Asthma is an increasingly common disorder, affecting 5–10% of the population. It involves a dysregulated immune function, which may predispose to subsequent cancer. We examined cancer risk among Swedish subjects who had hospital admission once or multiple times for asthma. An asthma research database was created by identifying asthma patients from the Swedish Hospital Discharge Register and by linking them with the Cancer Registry. A total of 140 425 patients were hospitalised for asthma during 1965–2004, of whom 7421 patients developed cancer, giving an overall standardised incidence ratio (SIR) of 1.36. A significant increase was noted for most sites, with the exception of breast and ovarian cancers and non-Hodgkin's lymphoma and myeloma. Patients with multiple hospital admissions showed a high risk, particularly for stomach (SIR 1.70) and colon (SIR 1.99) cancers. A significant decrease was noted for endometrial cancer and skin melanoma. Oesophageal and lung cancers showed high risks throughout the study period, whereas stomach cancer increased towards the end of the period. The relatively stable temporal trends suggest that the asthmatic condition rather than its medication is responsible for the observed associations.

The effect of a 12 week walking intervention on markers of insulin resistance and systemic inflammation

OBJECTIVES

The purpose of the present study was to determine whether a community-based walking intervention, using pedometers, is effective in reducing systemic inflammatory markers.

METHODS

Participants (age=49(8.9)) were recruited in Glasgow, United Kingdom, from August to December 2006 and were randomly assigned to a control (n=24; 6 males, no change in walking) and intervention group (n=24; 5 males gradually increasing walking by 3000 steps/day on 5 days of the week). Blood samples were collected at baseline, and after 12 weeks, and analysed for glucose, insulin, high sensitivity C-reactive protein (hsCRP), interleukin-6 (IL-6), soluble IL-6 receptor (sIL-6R), tumour necrosis factor-alpha (TNF-alpha) and soluble TNF receptors I and II (sTNFR1 and sTNFRII).

RESULTS

In the control group baseline step counts were 6356 (2953) steps/day and did not change (P>0.05) after 12 weeks, 6709 (2918) steps/day. The intervention group increased (P<0.001) step count from 6682 (3761) steps/day at baseline to 10182 (4081) steps/day at 12 weeks. Over the 12 week period there was no change in any other variables measured, in either control or intervention group.

CONCLUSION

We conclude that the current community-based intervention did not affect systemic markers of inflammation or insulin sensitivity.

The response of plasma interleukin-6 and its soluble receptors to exercise in the cold in humans

In this study, we wished to determine whether the changes in metabolism observed during exercise in the cold are associated with changes in interleukin-6 (IL-6) and/or its soluble receptors. Eight healthy male participants performed 1 h of cycling exercise at 70% VO2max in a control (20 degrees C) and cold (0 degrees C) environment. Plasma concentrations of IL-6, soluble IL-6 receptor (sIL-6R), and sgp130 were measured before exercise, at 30 and 60 min of exercise, and 60 min after exercise. Substrate oxidation was estimated through measures of pulmonary gas exchange recorded between 50 and 55 min of cycling. Exercise in the cold resulted in an increase (P < 0.05) in carbohydrate oxidation (mean 2.58 g.min(-1), s = 0.49 at 20 degrees C vs. 2.85 g.min(-1), s = 0.58 at 0 degrees C) and a decrease (P < 0.05) in fat oxidation (0.55 g.min(-1), s = 0.17 at 20 degrees C vs. 0.38 g.min(-1), s = 0.16 at 0 degrees C) compared with the control trial. Interleukin-6 concentrations were elevated (P < 0.05) after 60 min of exercise in both the cold and control trials, with no differences between trials at any instant. Neither sIL-6R nor sgp130 was affected by exercise or the environment. The alterations in carbohydrate and fat utilization during 1 h of exercise in the cold are not paralleled by changes in plasma concentrations of IL-6 or its soluble receptors.

Pre-analytical and biological variability in circulating interleukin 6 in healthy subjects and patients with rheumatoid arthritis

Interleukin (IL)-6, a key player in the inflammatory response, may be a useful biomarker in rheumatoid arthritis (RA). The aim was to determine analytical variability, a reference interval in healthy subjects, and long- and short-term variation in serum and plasma IL-6 in healthy subjects and RA patients. An enzyme-linked immunosorbent assay from R&D was used for determination of serum and plasma IL-6. The IL-6 concentration did not depend on the type of anticoagulant used or the 3-h time delay between sampling and processing or repeated freeze-thaw cycles. The median plasma and serum IL-6 in 318 healthy subjects were 1.3 pg ml(-1) (range 0.33-26) and 1.4 pg ml(-1) (range 0.25-23), respectively. The median coefficient of variation in plasma IL-6 in 27 healthy subjects during 1 month, and repeated after 6 and 12 months were 27%, 31% and 26%, respectively. No significant long-term changes were observed in serum IL-6 over a 3-year period (14%, p = 0.33). Exercise (cycling) increased serum IL-6 in healthy subjects but not in RA patients. In conclusion, circulating IL-6 is stable regarding sample handling and shows little variation over time. Changes in IL-6 concentrations > 60% (2 times the biological variation) are likely to reflect changes in disease activity and not only pre-analytical or normal biological variability.

ZPDC glycoprotein inhibits inflammation-related cytokine and protein via nuclear factor-kappa B in dextran sulfate sodium-stimulated ICR mouse

The purpose of this study is to investigate the anti-inflammatory potentials of a 24-kDa glycoprotein isolated from Zanthoxylum piperitum DC fruit (ZPDC glycoprotein) in dextran sulfate sodium (DSS)-stimulated ICR mouse colitis. ZPDC glycoprotein was administered to mice at 10 and 20 mg/kg for 7 days and then the mice were co-treated with 5% DSS for another 7 days in presence of ZPDC glycoprotein and killed on day 15. The results showed that ZPDC glycoprotein has inhibitory effects on levels of disease activity index and large intestine shortening in DSS-treated mice. In addition, ZPDC glycoprotein suppresses the formation of thiobarbituric acid reactive substances, production of inducible nitric oxide, and release of lactate dehydrogenase in DSS-treated mice plasma. Interestingly, we found that consumption of ZPDC glycoprotein (20 mg/kg) significantly inhibited the expressions of interleukin-1beta and tumor necrosis factor-alpha, inducible nitric oxide synthase, and cyclooxygenase-2 via modulation of transcriptional activity of nuclear factor-kappa B in DSS-treated mice colon. Collectively, these results suggest that ZPDC glycoprotein is useful for prevention of inflammatory gastrointestinal diseases.

Immunomodulatory properties of two wheat bran fractions - aleurone-enriched and crude fractions - in obese mice fed a high fat diet

Several data suggest that fermentable dietary fibers could play a role in the control of obesity and associated metabolic disorders. In mice, dietary fructans, which are extensively fermented in caeco-colon by bifidobacteria, decrease fat mass development and modulate gastrointestinal peptides involved in the control of food intake (namely glucagon-like peptide (GLP)-1). The aim of this study was to compare the effect of two cereal bran fractions isolated from wheat - aleurone-enriched and crude fractions - in a nutritional model of obesity. In a first experiment, we confirmed that 2 weeks of treatment with a high fat (HF) diet is sufficient to exhibit glucose intolerance and to increase adiposity in mice. In the second experiment, mice were fed a HF or a HF diet enriched with 10% wheat bran fractions during 3 weeks. None of the wheat bran fractions modified body weight, adipose tissue mass, glucose or lipid homeostasis. Wheat bran fractions increased bifidobacteria and lactobacilli in the caecal content without any effect on caecal enlargement and on GLP-1 precursor expression in the colon. Furthermore, wheat bran fractions decreased circulating interleukin 6 (IL-6) and CD68 mRNA in the visceral adipose tissue, suggesting a decrease in recruited-tissue macrophages. We propose that specific and early immunomodulatory properties of cereal products with prebiotic properties, may occur in obese mice independently of extensive gut fermentation.

Preeclampsia-related inflammatory cytokines regulate interleukin-6 expression in human decidual cells

Preeclampsia, a common pregnancy disorder associated with an increase in systemic inflammation, is the leading cause of maternal and fetal morbidity and mortality throughout the world. It is associated with shallow extravillous trophoblast invasion of the decidua, leading to uteroplacental blood flow that is inadequate for the developing fetal-placental unit. In preeclamptic women, interleukin-6 (IL-6) levels in plasma, but not placenta, are elevated, prompting evaluation of the decidua as a potential source of this excess, circulating IL-6. The current study found significantly higher immunohistochemical staining for IL-6 in decidual cells from preeclamptic versus preterm, gestational age-matched control placentas. Pro-inflammatory cytokines associated with the genesis of preeclampsia (i.e., tumor necrosis factor-alpha and interleukin-1beta) enhanced IL-6 mRNA levels and increased secreted IL-6 levels in first trimester leukocyte-free decidual cell incubations, as measured by real time quantitative RT-PCR, ELISA, and Western blotting. Therefore, decidual cell-derived IL-6 may contribute to excess circulating IL-6 levels that can promote both endothelial cell dysfunction (and subsequent vascular dysfunction) and the pathogenesis of preeclampsia whereas locally elevated IL-6 levels may contribute to an excess of decidual macrophages implicated in shallow extravillous trophoblast invasion of the decidua.

IL-15Ralpha chaperones IL-15 to stable dendritic cell membrane complexes that activate NK cells via trans presentation

Natural killer (NK) cells are innate immune effectors that mediate rapid responses to viral antigens. Interleukin (IL)-15 and its high affinity IL-15 receptor, IL-15Ralpha, support NK cell homeostasis in resting animals via a novel trans presentation mechanism. To better understand how IL-15 and IL-15Ralpha support NK cell activation during immune responses, we have used sensitive assays for detecting native IL-15 and IL-15Ralpha proteins and developed an assay for detecting complexes of these proteins. We find that IL-15 and IL-15Ralpha are preassembled in complexes within the endoplasmic reticulum/Golgi of stimulated dendritic cells (DCs) before being released from cells. IL-15Ralpha is required for IL-15 production by DCs, and IL-15 that emerges onto the cell surface of matured DCs does not bind to neighboring cells expressing IL-15Ralpha. We also find that soluble IL-15-IL-15Ralpha complexes are induced during inflammation, but membrane-bound IL-15-IL-15Ralpha complexes, rather than soluble complexes, support NK cell activation in vitro and in vivo. Finally, we provide in vivo evidence that expression of IL-15Ralpha specifically on DCs is critical for trans presenting IL-15 and activating NK cells. These studies define an unprecedented cytokine-receptor biosynthetic pathway in which IL-15Ralpha serves as a chaperone for IL-15, after which membrane-bound IL-15Ralpha-IL-15 complexes activate NK cells via direct cell-cell contact.

C-reactive protein in liver cancer surgery

AIMS

The aim of this article is to review the current state of knowledge with regard to the importance of C-reactive protein (CRP) in patients undergoing hepatic resection for malignancy both in terms of its role as an acute phase reactant and predictor of outcome.

METHODS

An electronic search was performed of the medical literature using the MEDLINE database to identify relevant articles that included the search terms: C-reactive protein; CRP; hepatocellular carcinoma; colorectal liver metastases; hepatic resection; and liver resection.

RESULTS

The limited published data in relation to CRP and liver resection is contradictory. There are studies correlating an acute phase reactant-type postoperative rise in CRP with both good and poor outcome following colorectal liver metastases resection. In relation to prognosis, the only available publication indicates that a high preoperative CRP is a poor prognostic indicator in relation to patient survival. Data for CRP and resection of HCC is equally as limited with early evidence suggesting a correlation between CRP and stage of disease, and documenting an acute temporary elevation in CRP following resection.

CONCLUSIONS

The importance of CRP as a marker of both early postoperative outcome and long-term prognosis in patients with hepatic malignancies is at present unclear. Further studies are required to clarify the changes and more accurately define the mechanism by which CRP is being up-regulated.

Response of plasma IL-6 and its soluble receptors during submaximal exercise to fatigue in sedentary middle-aged men

The pleiotropic cytokine interleukin-6 (IL-6) has been demonstrated to increase during exercise. Little is known regarding the response of the soluble IL-6 receptors (sIL-6R and sgp130) during such exercise. The aim of the current study was to investigate the response of plasma IL-6, sIL-6R and sgp130 during fatiguing submaximal exercise in humans. Twelve participants underwent an incremental exercise test to exhaustion and one week later performed a submaximal exercise bout (96 +/- 6% lactate threshold) to volitional exhaustion. Blood samples taken at rest and immediately post exercise were analyzed for IL-6, sIL-6R and sgp130. IL-6 increased (P < 0.01) by 8.4 +/- 8.9 pg ml(-1) (75.7%) during the exercise period. sIL-6R and sgp130 also increased (P < 0.05) by 2.7 +/- 3.9 ng ml(-1) (9.6%) and 37.7 +/- 55.6 ng ml(-1) (9.6%), respectively. The current study is the first investigation to demonstrate that alongside IL-6, acute exercise stress results in an increase in both sIL-6R and sgp130.

Convergence of genetic, nutritional and inflammatory factors in gastrointestinal cancers

Gastrointestinal cancers account for 20% of all cancer incidences worldwide. Colorectal cancer is the second most common cause of all cancer-related mortality and is increasing in Western societies. Infection and inflammation contribute to 15-20% of all malignancies, and are predisposing risk factors for gastrointestinal cancers. Helicobacter pylori infection is commonly associated with gastric cancers, and chronic inflammation increases the risk of colorectal cancer by 1% per year. Micronutrient status and common genetic variations in human populations modify risk for gastrointestinal cancer. Chronic inflammation promotes carcinogenesis by inducing gene mutations, inhibiting apoptosis, and stimulating angiogenesis and cell proliferation. Inflammation also induces epigenetic alterations that are associated with cancer development. Two key genes in the inflammatory process, cyclooxygenase-2 (COX-2) and nuclear factor-kappa B (NF-kappaB), provide a mechanistic link between inflammation and cancer and are targets for chemoprevention. Dietary components, and human genetic variation that affects nutrient utilization, can directly modify inflammatory processes and/or suppress genomic alterations that are the molecular antecedents of cancers. The present report focuses on the convergence of genetic, nutritional, and inflammatory factors in the initiation and progression of gastrointestinal cancers, and the emerging dietary strategies for cancer prevention.

Interleukin-6 (IL-6) and receptor (IL6-R) gene haplotypes associate with amniotic fluid protein concentrations in preterm birth

Spontaneous preterm birth (PTB-gestational age <37 weeks) occurs in approximately 450 000 births annually in the United States and is one of the leading causes of neonatal morbidity and mortality. Risk of PTB is affected by complex gene-environment interactions that are not well understood. We examined the PTB candidate gene, Interleukin 6 (IL-6) and its receptor (IL6-R) in both Caucasian (145 PTB and 194 term maternal; 140 PTB and 179 term fetal) and African-American (76 PTB and 191 term maternal; 66 PTB and 183 term fetal) DNA. Eight single nucleotide polymorphisms (SNPs) in IL-6 and 22 SNPs in IL6R were examined for association with IL-6 amniotic fluid (AF) concentrations, as concentration of IL-6 is a hypothesized risk factor. In addition, IL-6 and IL6-R SNPs were analyzed for associations with PTB. Haplotype associations were tested by sliding windows. No strong single marker effects were observed in Caucasians; however, in African-American maternal IL-6R marker rs4553185 associated with PTB (allele P = 4.49 x 10(-3) and genotype P = 0.01). The strongest haplotype associations were observed in IL-6R with IL-6 cytokine concentration as outcome: Caucasian fetal (rs4601580-rs4845618) P = 1.6 x 10(-3) and African-American maternal (rs4601580-rs4845618-rs6687726-rs7549338) P = 2.30 x 10(-3). Significant results converged on three regions in the two genes: in IL-6 markers rs1800797, rs1800796 and rs1800795; in IL-6R markers rs4075015, rs4601580, rs4645618, rs6687726 and rs7549338 and markers rs4845623, rs4537545 and rs4845625. In conclusion, our results suggest that IL-6 AF concentration, in situations of PTB, result from variation in IL-6 and more importantly IL-6R.

Mutations in the EGFR kinase domain mediate STAT3 activation via IL-6 production in human lung adenocarcinomas

Persistently activated or tyrosine-phosphorylated STAT3 (pSTAT3) is found in 50% of lung adenocarcinomas. pSTAT3 is found in primary adenocarcinomas and cell lines harboring somatic-activating mutations in the tyrosine kinase domain of EGFR. Treatment of cell lines with either an EGFR inhibitor or an src kinase inhibitor had no effect on pSTAT3 levels, whereas a pan-JAK inhibitor (P6) blocked activation of STAT3 and inhibited tumorigenesis. Cell lines expressing these persistently activated mutant EGFRs also produced high IL-6 levels, and blockade of the IL-6/gp130/JAK pathway led to a decrease in pSTAT3 levels. In addition, reduction of IL-6 levels by RNA interference led to a decrease in tumorigenesis. Introduction of persistently activated EGFR into immortalized breast epithelial cells led to tumorigenesis, IL-6 expression, and STAT3 activation, all of which could be inhibited with P6 or gp130 blockade. Furthermore, inhibition of EGFR activity in multiple cell lines partially blocked transcription of IL-6 and concurrently decreased production and release of IL-6. Finally, immunohistochemical analysis revealed a positive correlation between pSTAT3 and IL-6 positivity in primary lung adenocarcinomas. Therefore, mutant EGFR could activate the gp130/JAK/STAT3 pathway by means of IL-6 upregulation in primary human lung adenocarcinomas, making this pathway a potential target for cancer treatment.

Humanized antihuman IL-6 receptor antibody, tocilizumab

Interleukin-6 (IL-6) is a pleiotropic cytokine that regulates immune responses and inflammatory reactions. Overproduction of IL-6 has been shown to play a role in inflammatory autoimmune diseases such as rheumatoid arthritis (RA), and juvenile idiopathic arthritis (JIA) and, therefore, an agent blocking IL-6 actions can be a therapy of these diseases. IL-6 belongs to a cytokine family, which shares the cytokine receptor subunit glycoprotein (gp) 130. This family also includes IL-11, oncostatin-M, and leukemia inhibitory factor (LIF). In the IL-6 receptor (IL-6R) system, both a membrane-bound IL-6R and a soluble form of IL-6R are able to mediate IL-6 signals into the cells through the interaction of gp130. Tocilizumab is a humanized antihuman IL-6 receptor antibody designed using genetic engineering technology. Tocilizumab recognizes both the membrane-bound and the soluble form IL-6R and specifically blocks IL-6 actions. Tocilizumab is expected to ameliorate the autoimmune inflammatory diseases with IL-6 overproduction and has been clinically developed as a therapeutic agent for RA, systemic-onset and articular types of JIA, Crohn's disease, etc. Tocilizumab has been shown to be effective not only for improving signs and symptoms but also for preventing joint destruction of RA. Immunopharmacology and clinical benefit of tocilizumab in RA is addressed.

Maternal allergy influences p38-mitogen-activated protein kinase activity upon microbial challenge in CD14+ monocytes from 2-year-old children

BACKGROUND

The development of allergic diseases is dependent on genetic and environmental factors. It has been shown previously that cord blood mononuclear cells (CBMCs) from infants with parental allergy have altered cytokine profiles upon bacterial encounter; it might be possible that such impairment persists during the early years of childhood.

OBJECTIVE

The aim of this study was to investigate anti-microbial responses with regard to p38-mitogen-activated protein kinase (MAPK) activity in CD14(+) monocytes and IL-6 release from mononuclear cells in the same group of children at birth and at 2 years of age. Methods Paired samples of CBMCs and peripheral blood mononuclear cells (PBMCs) were stimulated with either lipopolysaccharide (LPS) or peptidoglycan in vitro. CD14(+) monocytes were analysed for p38-MAPK activity by flow cytometry, and soluble IL-6 receptor, soluble glycoprotein130 and IL-6 release from PBMC cultures were quantified by ELISA.

RESULTS

CBMCs from newborns with allergic mothers tended to have a lower IL-6 response following an LPS (P=0.09) challenge compared with the group without maternal allergy while p38-MAPK activation levels did not differ between the groups. PBMCs from 2-year-olds with allergic mothers released significantly less (P<0.05) IL-6 upon peptidoglycan stimuli compared with age-matched infants with non-allergic mothers. Infants with allergic mothers displayed markedly reduced CD14(+) monocyte p38-MAPK phosphorylation after LPS (P<0.05) and peptidoglycan (P<0.01) challenge. This altered anti-microbial response was attributed to maternal allergy rather than to being IgE-sensitized at 2 years of age.

CONCLUSION

Monocytes from children with allergic mothers are less responsive to bacterial challenge than monocytes from children with non-allergic mothers, and this impairment persists during the first 2 years of infancy.

Interleukin-6 and its receptor in cancer: implications for translational therapeutics

Interleukin-6 (IL-6) plays a major role in the response to injury or infection and is involved in the immune response, inflammation, and hematopoiesis. Its deregulation impacts numerous disease states, including many types of cancer. Consequently, modulating IL-6 may be an innovative therapeutic strategy in several diseases. A review of relevant published literature regarding IL-6 and its receptor was performed. In addition, a review of the relevance of this cytokine system to human illness, particularly in cancer, was undertaken. IL-6 is a pleiotropic cytokine that is involved in the physiology of virtually every organ system. Aberrant expression of this cytokine has been implicated in diverse human illnesses, most notably inflammatory and autoimmune disorders, coronary artery and neurologic disease, gestational problems, and neoplasms. In cancer, high levels of circulating IL-6 are observed in almost every type of tumor studied and predict a poor outcome. Furthermore, elevated IL-6 levels are associated strongly with several of the striking phenotypic features of cancer. Several molecules have been developed recently that target the biologic function of IL-6. Early results in the clinic suggest that this strategy may have a significant salutary impact on diverse tumors. The field of cytokine research has yielded a deep understanding of the fundamental role of IL-6 and its receptor in health and disease. Therapeutic targeting of IL-6 and its receptor in cancer has strong biologic rationale, and there is preliminary evidence suggesting that targeting of the IL-6 system may be beneficial in the treatment of cancer.

Emerging drugs for biliary cancer

Biliary cancer comprise carcinoma of the gallbladder as well as the intrahepatic, hilar and extrahepatic bile ducts. Furthermore, many different etiologies and risk factors are contributing to the inhomogeneity of this disease. It is often diagnosed at an advanced stage when potentially curative resection is not feasible. Due to the lack of randomised Phase III studies, there is no standard regimen for chemotherapy in biliary cancer. Recent investigations into the underlying molecular mechanisms involved in biliary carcinogenesis and tumour growth have contributed greatly to our understanding of biliary cancer. Through a better understanding of these mechanisms, improved and more specific diagnostic, therapeutic and preventive strategies may be developed. Although fluoropyrimidines and gemcitabine remain the backbone of routine chemotherapy in advanced disease, new agents such as epidermal growth factor receptor blockers and angiogenesis inhibitors may hold promise for improving the outcome for patients with biliary cancer.

Interleukin-6 trans signalling enhances photodynamic therapy by modulating cell cycling

Photodynamic therapy (PDT) of solid tumours causes tissue damage that elicits local and systemic inflammation with major involvement of interleukin-6 (IL-6). We have previously reported that PDT-treated cells lose responsiveness to IL-6 cytokines. Therefore, it is unclear whether PDT surviving tumour cells are subject to regulation by IL-6 and whether this regulation could contribute to tumour control by PDT. We demonstrate in epithelial tumour cells that while the action of IL-6 cytokines through their membrane receptors is attenuated, regulation by IL-6 via trans-signalling is established. Soluble interleukin-6 receptor-α (IL-6Rα) (sIL-6Rα) and IL-6 were released by leucocytes in the presence of conditioned medium from PDT-treated tumour cells. Cells that had lost their membrane receptor IL-6Rα due to PDT responded to treatment with the IL-6R–IL-6 complex (Hyper-IL-6) with activation of signal transducers and activator of transcription (STAT3) and ERK. Photodynamic therapy-treated cells, which were maintained during post-PDT recovery in presence of IL-6 or Hyper-IL-6, showed an enhanced suppression of proliferation. Cytokine-dependent inhibition of proliferation correlated with a decrease in cyclin E, CDK2 and Cdc25A, and enhancement of p27kip1 and hypophosphorylated Rb. The IL-6 trans-signalling-mediated attenuation of cell proliferation was also effective in vivo detectable by an improved Colon26 tumour cure by PDT combined with Hyper-IL-6 treatment. Prevention of IL-6 trans-signalling using soluble gp130 reduced curability. The data suggest that the post-PDT tumour milieu contains the necessary components to establish effective IL-6 trans-signalling, thus providing a means for more effective tumour control.

Overexpression of interleukin-1beta and interleukin-6 may play an important role in periodontal breakdown in type 2 diabetic patients

BACKGROUND AND OBJECTIVE

This study evaluated whether the biochemical changes associated with type 2 diabetes modulate the expression of interleukin-1beta, interleukin-6, interleukin-8, and interferon-gamma in sites with chronic periodontitis.

MATERIAL AND METHODS

Biopsies were harvested and divided into three groups: group 1, systemically and periodontally healthy subjects (n = 10); group 2, systemically healthy subjects with moderate-to-severe chronic periodontitis (probing depth > 6 mm) (n = 20); and group 3, type 2 diabetic subjects with periodontitis (n = 20). Cytokine levels were assessed in the gingival tissues by enzyme-linked immunosorbent assay analysis.

RESULTS

Data analysis demonstrated that the interleukin-1beta, interleukin-6, interleukin-8, and interferon-gamma levels were higher in the presence of periodontal inflammation than in the absence of inflammation, regardless of systemic status. The interleukin-1beta and interleukin-6 levels were higher in diabetic subjects (group 3) than in systemically healthy patients with comparable types of periodontitis (group 2). No difference was observed for the interleukin-8 and interferon-gamma levels between groups 2 and 3.

CONCLUSION

Within the limits of this study, it was concluded that type 2 diabetes was associated with increased expression of interleukin-1beta and interleukin-6 in periodontally inflamed tissues of diabetic patients, relative to nondiabetic subjects, and that such overexpression may be involved in the mechanisms by which type 2 diabetes enhances periodontal destruction.

Rapid reversal of interleukin-6-dependent epithelial invasion in a mouse model of microbially induced colon carcinoma

Chronic inflammation of mucosal surfaces renders them increasingly susceptible to epithelial cancers both in humans and mice. We have previously shown that anti-inflammatory CD4(+)CD45RB(lo)CD25(+) regulatory (Treg or T(R)) lymphocytes down-regulate inflammation and block development of bacteria-triggered colitis and colorectal cancer (CRC) in 129/SvEv Rag2-/- mice. Interestingly, T(R) cells collected from Interleukin (IL)-10-deficient cell donors not only failed to suppress carcinogenesis but instead promoted invasive mucinous colonic carcinoma with a strong gender bias expressing in male mice. We found we show that peritoneal invasion in this model is dependent on pleiotropic cytokine IL-6. Mucinous carcinoma arose rapidly and consistently after treatment with IL10-/- T(R) cells, which were found to express Foxp3+ and localize throughout tumor tissue. Carcinogenesis was rapidly reversible with transfer of wild type IL10-competent T(R) cells. Likewise, treatment with IL10-Ig fusion protein was sufficient to revert the lesions histologically, and restore inflammatory cytokine and oncogene expression to base line levels. These studies indicate an essential role for IL 6 in this CRC phenotype. Furthermore, immune-competent T(R) cells were important not only for preventing pathology but also for constructive remodeling of bowel following tumorigenic microbial insults. These data provide insights into etiopathogenesis of inflammation-associated epithelial invasion and maintenance of epithelial homeostasis.

Cinnamaldehyde inhibits pro-inflammatory cytokines secretion from monocytes/macrophages through suppression of intracellular signaling

We investigated the in vitro anti-inflammatory effects of Cinnamaldehyde, a cytokine production inhibitor isolated from an essential oil produced from the leaves of Cinnamomum osmophloeum Kaneh, and its mechanism of action. Although Cinnamaldehyde has been reported to have contact sensitizing properties at high concentration (mM), we found that low concentration of Cinnamaldehyde (muM) inhibited the secretion of interleukin-1beta and tumor necrosis factor alpha within lipopolysaccharide (LPS) or lipoteichoic acid (LTA) stimulated murine J774A.1 macrophages. Cinnamaldehyde also suppressed the production of these cytokines from LPS stimulated human blood monocytes derived primary macrophages and human THP-1 monocytes. Furthermore, Cinnamaldehyde also inhibited the production of prointerleukin-1beta within LPS or LTA stimulated human THP-1 monocytes. Reactive oxygen species release from LPS stimulated J774A.1 macrophages was reduced by Cinnamaldehyde. The phosphorylation of extracellular signal-regulated kinase 1/2 and c-Jun N-terminal kinase 1/2 induced by LPS was also inhibited by Cinnamaldehyde; however, Cinnamaldehyde neither antagonize the binding of LPS to the cells nor alter the cell surface expression of toll-like receptor 4 and CD14. In addition, we also noted that Cinnamaldehyde appeared to elicit no cytotoxic effect upon J774A.1 macrophages under our experimental conditions, although Cinnamaldehyde reduced J774A.1 macrophages proliferation as analysed by MTT assay. Our current results have demonstrated the anti-oxidation and anti-inflammatory properties of Cinnamaldehyde that could provide the possibility for Cinnamaldehyde's future pharmaceutical application in the realm of immuno-modulation.

A common variant of the interleukin 6 receptor (IL-6r) gene increases IL-6r and IL-6 levels, without other inflammatory effects

Interleukin-6 (IL-6) is a key inflammatory cytokine, signalling to most tissues by binding to a soluble IL-6 receptor (sIL-6r), making a complex with gp130. We used 1273 subjects (mean age 68 years) from the InCHIANTI Italian cohort to study common variation in the IL-6r locus and associations with interleukin 6 receptor (IL-6r), IL-6, gp130 and a battery of inflammatory markers. The rs4537545 single nucleotide polymorphism (SNP) tags the functional non-synonymous Asp358Ala variant (rs8192284) in IL-6r (r(2)=0.89, n=343). Individuals homozygous for the rs4537545 SNP minor allele (frequency 40%) had a doubling of IL-6r levels (132.48 pg/ml, 95% CI 125.13-140.27) compared to the common allele homozygous group (68.31 pg/ml, 95% CI 65.35-71.41): in per allele regression models, the rs4537545 SNP accounted for 20% of the variance in sIL-6r, with P=5.1 x 10(-62). The minor allele of rs4537545 was also associated with higher circulating IL-6 levels (P=1.9 x 10(-4)). There was no association of this variant with serum levels of gp130 or with any of the studied pro- and anti-inflammatory markers. A common variant of the IL-6r gene results in major changes in IL-6r and IL-6 serum levels, but with no apparent effect on gp130 levels or on inflammatory status in the general population.

Chemopreventive effect of plant originated glycoprotein on colitis-mediated colorectal cancer in A/J mice

This study was carried out to investigate the chemopreventive effects of glycoprotein (UDN glycoprotein, 116-kDa) isolated from Ulmus davidiana Nakai on colitis-mediated colorectal cancer (CRC) in A/J mice. UDN glycoprotein intake significantly reduced the incidence and the multiplicity of colorectal tumors, induced by combination treatment with 10 mg/kg 1,2-dimethylhydrazine (DMH) and 2% dextran sodium sulfate (DSS). We found that the abnormal levels of lactate dehydrogenase (LDH), thiobarbituric acid reactive substances (TBARS), and nitric oxide (NO) were significantly suppressed in proportion to the concentration of UDN glycoprotein (0.01% and 0.02%) in the mice serum. In addition, consumption of UDN glycoprotein attenuated the activities of proliferating cell nuclear antigen (PCNA), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2), and inhibited the DNA-binding activities of nuclear factor-kappa B (NF-kappaB) and activator protein-1 (AP-1) in the mice colonic tissue. Interestingly, the results obtained from reverse transcription polymerase chain reaction (RT-PCR) assay showed that 0.02% UDN glycoprotein inhibited the expressions of tumor necrosis factor (TNF)-alpha and interleukin (IL)-6 mRNA in the mice. Collectively, these results suggest that UDN glycoprotein has chemopreventive activity via modulation of inflammation-related factors responsible for development of colitis-mediated CRC in A/J mice.