IL-6) And Its Receptor Research Articles

Association of the IL6 rs1800796, but not of the IL6 rs1800795, IL6R rs4845617 and rs2228145 polymorphisms with hip fracture in elderly Mexican women.

Polymorphisms in Interleukin-6 (IL6) and its receptor (IL6R) have been associated with bone mineral density. In this work, the G-174C and G-572C polymorphisms in IL6, G-208A, and Asp358Ala in IL6R were analyzed in Mexican women with hip fracture. Postmenopausal Mexican women (60 years or over) with hip fragility fracture (77.97 ± 8 years) and without hip fracture (70.5 ± 7.02 years) were genotyped by real-time PCR. The rs1800796 GG genotype was associated with low risk of fracture (p = 0.05), while GC genotype was associated with high risk of fracture [p = 0.047, OR 2.3 (95% CI 1.013-5.2)]. The AA genotype of the rs2228145 SNP (IL6R) was significantly different [p = 0.033, OR 1.94 (95% CI 1.01-3.75)], but when data were adjusted by age and body mass index, there were no differences (p = 0.9). Our results suggest that the IL6 rs1800796 SNP is a good marker for hip fracture risk in Mexican women.

Association of genetic variations in IL-6/IL-6R pathway genes with gastric cancer risk in a Chinese population

Interleukin-6 (IL-6) and its receptor (IL-6R) were regarded to be responsible for the occurrence of gastric cancer for their regulation roles in the inflammation. The genetic variations in these two genes (IL-6: rs6949149, rs1800796, rs10499563 and IL-6R: rs2228145) have been suggested to be associated with gastric cancer risk. However, the published results were inconsistent among subjects of different ethnicity. To evaluate such an association in Chinese population, we carried out this case-control study based on 473 patients with gastric cancer and 474 healthy controls, whose genotypes were detected by the Sequenom MassARRAY platform, and Helicobacter pylori infection was assessed by immunogold testing kit. This study showed that rs1800796 CG genotype was associated with decreased risk of gastric cancer (adjusted OR=0.75, 95% CI: 0.57–0.99, p=0.043). The stratified analysis revealed that, in the Helicobacter pylori negative infection subgroup, rs2228145 AC (adjusted OR=0.64, 95% CI: 0.42–0.97) and AC/CC (adjusted OR=0.66, 95% CI: 0.45–0.99) genotypes were associated with decreased risk of gastric cancer, respectively. In contrast, in the Helicobacter pylori positive infection subgroup, rs10499563 TC (adjusted OR=0.64, 95% CI: 0.43–0.95), CC (adjusted OR=0.35, 95% CI: 0.14–0.90), TC/CC (adjusted OR=0.59, 95% CI: 0.40–0.87) genotype were associated with decreased gastric cancer risk, respectively. Moreover, in the male subgroup, rs1800796 CG (adjusted OR=0.61, 95% CI: 0.44–0.84) and CG/GG (adjusted OR=0.67, 95% CI: 0.49–0.91) genotype were associated with decreased risk of gastric cancer, respectively. In short, this study suggested that IL-6R rs2228145 and IL-6 rs10499563 genotype were associated with decreased risk of gastric cancer for the individuals with negative and positive Helicobacter pylori infection.

Interleukin 6 receptor is an independent prognostic factor and a potential therapeutic target of ovarian cancer.

Ovarian cancer remains the most lethal gynecologic cancer and new targeted molecular therapies against this miserable disease continue to be challenging. In this study, we analyzed the expressional patterns of Interleukin-6 (IL-6) and its receptor (IL-6R) expression in ovarian cancer tissues, evaluated the impact of these expressions on clinical outcomes of patients, and found that a high-level of IL-6R expression but not IL-6 expression in cancer cells is an independent prognostic factor. In in vitro analyses using ovarian cell lines, while six (RMUG-S, RMG-1, OVISE, A2780, SKOV3ip1 and OVCAR-3) of seven overexpressed IL-6R compared with a primary normal ovarian surface epithelium, only two (RMG-1, OVISE) of seven cell lines overexpressed IL-6, suggesting that IL-6/IL-6R signaling exerts in a paracrine manner in certain types of ovarian cancer cells. Ovarian cancer ascites were collected from patients, and we found that primary CD11b+CD14+ cells, which were predominantly M2-polarized macrophages, are the major source of IL-6 production in an ovarian cancer microenvironment. When CD11b+CD14+ cells were co-cultured with cancer cells, both the invasion and the proliferation of cancer cells were robustly promoted and these promotions were almost completely inhibited by pretreatment with anti-IL-6R antibody (tocilizumab). The data presented herein suggest a rationale for anti-IL-6/IL-6R therapy to suppress the peritoneal spread of ovarian cancer, and represent evidence of the therapeutic potential of anti-IL-6R therapy for ovarian cancer treatment.

Interleukin 6 Alters Localization of hMSH3, Leading to DNA Mismatch Repair Defects in Colorectal Cancer Cells

Elevated microsatellite alterations at selected tetranucleotide repeats (EMAST) is the most common DNA mismatch repair defect in colorectal cancers, observed in approximately 60% of specimens. This acquired genotype correlates with metastasis and poor outcomes for patients, and is associated with intra-epithelial inflammation and heterogeneous nuclear levels of the mismatch repair protein hMSH3. Inflammation and accompanying oxidative stress can cause hMSH3 to change its intracellular location, but little is known about the source of oxidative stress in cancer cells. We investigated whether cytokines mediate this process. We analyzed levels of interleukin 6 (IL6) and its receptor (IL6R) in human colon and lung cancer cell lines by flow cytometry and enzyme-linked immunosorbent assay; proteins were localized by immunofluorescence and immunoblot analyses. IL6 signaling was blocked with antibodies against IL6, soluble glycoprotein 130 Fc fragments, and the signal transducers and activators of transcription 3 inhibitor NSC74859; a constitutively active form of STAT3 was expressed in colon and lung cancer cell lines to replicate IL6R signaling. EMAST was detected by DNA fragment analysis. Immunohistochemistry was used to examine levels of IL6 in 20 colorectal tumor and adjacent nontumor tissues. Incubation of colon and lung cancer cell lines with IL6, but not other cytokines, caused hMSH3, but no other mismatch repair proteins, to move from the nucleus to the cytosol after generation of oxidative stress; inhibition of IL6 signaling prevented this shift. Expression of constitutively active STAT3 also caused hMSH3 to translocate from the nucleus to the cytoplasm in cancer cell lines. Incubation of cells with IL6 led to tetranucleotide frameshifts, the signature for EMAST. EMAST-positive colorectal tumors had significantly higher levels of IL6 than EMAST-negative tumors. IL6 signaling disrupts the nuclear localization of hMSH3 and DNA repair, leading to EMAST in cancer cell lines. Inflammatory cytokines might therefore promote genetic alterations in human cancer cells.

Family-based association study of interleukin 6 (IL6) and its receptor (IL6R) functional polymorphisms in schizophrenia in the Polish population.

Schizophrenia is a heterogeneous disorder and its etiology remains incompletely elucidated. Among possible causes, immunological factors have been implicated in its pathogenesis and course. The inflammatory system may trigger or modulate the course of schizophrenia through complex mechanisms influencing neurodevelopment, neuroplasticity and neurotransmission. Recent studies indicate a role of excessive interleukin-6 (IL6) signaling in the pathogenesis of schizophrenia. Findings regarding changes in the circulating levels of soluble interleukin-6 receptor (sIL6R) in schizophrenia have been equivocal. The study was performed on a group of 147 trio (patients diagnosed with schizophrenia and their healthy parents). Polymorphisms of IL6 (rs1800795, rs1800797) and IL6R (rs4537545, rs4845617, rs2228145) genes were genotyped with the use of TaqMan SNP Genotyping Assays. No association of the polymorphisms from IL6 and IL6R genes with schizophrenia was found. We also investigated haplotypes in IL6 gene (consisting of rs1800795 and rs1800797) and in IL6R gene (consisting of rs4537545, rs2228145). We also found no preference in transmission of any haplotype. Our results do not support the theory that polymorphisms of IL6 and IL6R genes are involved in the pathogenesis of schizophrenia. It seems advisable to carry out further examinations of the role of these polymorphisms in schizophrenia by means of TDT method and classical (case-control) association method.

Comparative analysis of IL6 and IL6 receptor gene polymorphisms in mastocytosis

Mastocytosis is a rare disease with reported high interleukin-6 (IL6) levels influencing disease severity. The present study investigated polymorphisms within the genes that encode IL6 and its receptor (IL6R) in relation to mastocytosis development in a case-control design. Analysis of the IL6R Asp358Ala polymorphism showed that carriers of the AA genotype had a 2·5-fold lower risk for mastocytosis than those with the AC or CC genotypes. No association with mastocytosis was found for the IL6-174G/C polymorphism, however, it may influence the effect of IL6R polymorphism. To the best of our knowledge this is the first study analysing IL6/IL6R polymorphisms in mastocytosis.

Expression of Interleukin–6 and Interleukin-6 Receptor in Ovine Oocytes During In vitroMaturation

To study the effects of interleukin-6 (IL-6) and its receptor (IL-6R) during in vitro maturation of ovine oocytes, the mRNA and protein expression levels of IL-6 and IL-6R, along with their localization, were examined during ovine oocytes maturation in vitro through real-time PCR, Western blotting, and immunohistochemistry. Specific patterns of expression of IL-6 and IL-6R were observed at both mRNA and protein levels at each stage of ovine oocytes maturation. IL-6 and IL-6R were distributed primarily on the surface of the cell membrane, with little expression in the cytoplasm or nucleus. IL-6 and IL-6R were expressed significantly at higher levels in the maturation around 4 h, and then decreased dramatically. However the level slightly elevated at 20-24 h. The role of IL-6 and IL-6R on oocytes maturation was studied through in vitro addition of recombinant human IL-6 in different concentrations. The addition of 10 ng mL−1 IL-6 significantly increased the rates of oocytes maturation (P<0.05), but did not affect the rates of development of the subsequence IVF ovine embryos. In summary, IL-6 is likely to play an important role in the early ovine oocytes maturation. The expression patterns of the IL-6 and IL-6R on the ovine oocytes maturation open up the possibility of regulatory role of the cytokine in ovine oocytes maturation.

Interleukin-6 and its receptor in the development of in vitro fertilized ovine embryos

To study the effects of interleukin-6 (IL-6) and its receptor (IL-6R) at each stage in the early development of in vitro-fertilized (IVF) sheep embryos, the mRNA and protein expression levels of IL-6 and IL-6R were evaluated along with their localization, through real-time PCR, protein blotting, and immunohistochemistry. Specific patterns of IL-6 and IL-6R expression were recorded at both the mRNA and protein level at each stage of early ovine embryonic development. IL-6 was distributed primarily on the cytoplasm, however IL-6R was concentrated much more on the cell membrane. The role of IL-6 and IL-6R in the early ovine embryonic development was studied via the in vitro addition of recombinant human IL-6, at different concentrations and RNA interference. The addition of the recombinant IL-6 increased the embryonic IL-6 mRNA level, and the addition of 10ng/mL IL-6 significantly increased the embryo cleavage rate (p<0.05). IL-6 RNA interference effectively reduced the IL-6 protein level, but did not affect the rate of development of the IVF ovine embryos. This study provides a practical basis for further indepth studies on the mechanisms involved during early ovine embryonic development.

Ethnic differences in interleukin 6 (IL‐6) and IL6 receptor genes in spontaneous preterm birth and effects on amniotic fluid protein levels

Preterm birth (PTB) is a significant neonatal health problem that is more common in African-Americans (AA) than in European-Americans (EA). Part of this disparity is likely to result from the differing genetic architectures of EA and AA. To begin assessing the role of these differences, patterns of genetic variation in two previously proposed candidate genes, encoding interleukin 6 (IL6) and its receptor (IL6R), were analyzed in mothers and fetuses from 496 EA birth-events (149 cases and 347 controls) and 397 birth-events in AA (76 cases and 321 controls). IL-6 levels in amniotic fluid (AF) samples were determined in a subset of these pregnancies. Case-control comparisons revealed a single SNP in IL6R associated with PTB (p=0.04 for allelic and p=0.05 for genotype association). In addition, all of the SNPs studied showed significant frequency differences between AA and EA in at least one comparison, significantly in excess of that expected from general population databases. Higher IL-6 concentrations were associated with the IL6 SNP -661 in EA preterm samples (p=0.0056), and this result seems to be driven by microbial invasion of the amniotic cavity, indicating a gene by infection interaction. These findings indicate that, as a function of IL6 genotype, EA and AA women respond differently to infection with respect to their expression of IL-6. Our data support differential genetic control of levels of IL-6 in amniotic fluid between EA and AA.

Interleukin-6 and IL-6 receptor cell expression in testis of rats with autoimmune orchitis

Experimental autoimmune orchitis (EAO) is an organ-specific model of autoimmunity characterized by an interstitial lymphomononuclear cell infiltrate as well as sloughing and apoptosis of germ cells. EAO was induced in adult male Sprague–Dawley rats by active immunization with testicular homogenate and adjuvants. Rats injected with saline solution and adjuvants were used as control group. The aim of this work was to study the expression of interleukin-6 (IL-6) and its receptor (IL-6R) in the testis of rats with EAO and analyze whether IL-6 could be involved in germ cell apoptosis. By immunohistochemistry, we detected IL-6 expression in testicular macrophages and Leydig cells of control and EAO rats. Sertoli cells showed IL-6 immunoreactivity in most of the seminiferous tubules of control rats, while a few IL-6 + Sertoli cells were found in the testis of rats with EAO. IL-6R immunoreactivity was observed in macrophages, Leydig and germ cells. A significant increase was noted in the number of IL-6R + germ cells in rats with EAO compared to control rats. The content of IL-6 (ELISA) in the conditioned media obtained from testicular macrophages of rats with orchitis was significantly higher than in the control group. By immunofluorescence performed on isolated testicular macrophages, IL-6 was shown to be expressed by monocytes recently arrived from circulation (ED1 + cells), while resident macrophages (ED2 + cells) were negative. In vitro experiments (trypan blue and MTS assays) showed that IL-6 (50 ng/ml) reduced germ cell viability. We demonstrated also using the TUNEL technique that IL-6 added to cultures of seminiferous tubule segments induced apoptosis of germ cells. Our results suggest that IL-6 and IL-6R may be involved in the pathogenesis of autoimmune orchitis by promoting testicular inflammation and germ cell apoptosis.

Co-expression of p16INK4a and Ki-67 in identical cells of cervical lesions as an independent sign of dysplasia

Elevated microsatellite alterations at selected tetranucleotide repeats (EMAST) is the most common DNA mismatch repair defect in colorectal cancers, observed in approximately 60% of specimens. This acquired genotype correlates with metastasis and poor outcomes for patients, and is associated with intra-epithelial inflammation and heterogeneous nuclear levels of the mismatch repair protein hMSH3. Inflammation and accompanying oxidative stress can cause hMSH3 to change its intracellular location, but little is known about the source of oxidative stress in cancer cells. We investigated whether cytokines mediate this process.We analyzed levels of interleukin 6 (IL6) and its receptor (IL6R) in human colon and lung cancer cell lines by flow cytometry and enzyme-linked immunosorbent assay; proteins were localized by immunofluorescence and immunoblot analyses. IL6 signaling was blocked with antibodies against IL6, soluble glycoprotein 130 Fc fragments, and the signal transducers and activators of transcription 3 inhibitor NSC74859; a constitutively active form of STAT3 was expressed in colon and lung cancer cell lines to replicate IL6R signaling. EMAST was detected by DNA fragment analysis. Immunohistochemistry was used to examine levels of IL6 in 20 colorectal tumor and adjacent nontumor tissues.Incubation of colon and lung cancer cell lines with IL6, but not other cytokines, caused hMSH3, but no other mismatch repair proteins, to move from the nucleus to the cytosol after generation of oxidative stress; inhibition of IL6 signaling prevented this shift. Expression of constitutively active STAT3 also caused hMSH3 to translocate from the nucleus to the cytoplasm in cancer cell lines. Incubation of cells with IL6 led to tetranucleotide frameshifts, the signature for EMAST. EMAST-positive colorectal tumors had significantly higher levels of IL6 than EMAST-negative tumors.IL6 signaling disrupts the nuclear localization of hMSH3 and DNA repair, leading to EMAST in cancer cell lines. Inflammatory cytokines might therefore promote genetic alterations in human cancer cells.

Expression of Interleukin 6 and Its Receptor in Human Gastric and Colorectal Cancers

Interleukin 6 (IL-6) is a pleiotropic cytokine with many physiological functions. The present study was designed to determine the expression of IL-6 and its receptor (IL-6R) in human gastric and colorectal cancers. Nine gastric- and nine colorectal cancer cell lines were analysed. The IL-6 gene was expressed in two gastric cancer cell lines and one colorectal cancer cell line; however, most of the cancer cell lines studied expressed the IL-6R gene. The level of IL-6 secretion in the gastric cancer cell lines correlated with the level of soluble IL-6R secretion, and was significantly higher (< approximately 100 pg/ml) than the level of IL-6 secretion in the colorectal cancer cell lines (< approximately 50 pg/ml). These results suggest that IL-6 may act in a paracrine fashion rather than an autocrine fashion in these cell lines.

Leukemia inhibitory factor, interleukin-6, and their receptors are expressed transiently in the olfactory mucosa after target ablation.

Removal of the synaptic targets of olfactory receptor neurons by olfactory bulb ablation results in apoptosis of olfactory receptor neurons and up-regulation of proliferation of their progenitors. This study focuses on the expression of the neuropoietic cytokines leukemia inhibitory factor (LIF) and its receptor (LIFR) and interleukin 6 (IL-6) and its receptor (IL-6R) in intercellular signaling pathways in the olfactory mucosa after target ablation. Olfactory bulbectomy (OBX) resulted in several transient, early-onset, temporally integrated events that were detected immunohistochemically. Macrophages infiltrated the olfactory epithelium (OE) by 16 hours post-OBX. LIF expression was up-regulated transiently at 2 days post-OBX, when up-regulated expression of LIFR also was detected on globose basal cells (GBCs), a subpopulation of which are immediate progenitors of olfactory receptor neurons. GBC proliferation peaked at 3--4 days post-OBX. In the olfactory nerve (ON), LIF-positive and IL-6-positive macrophage infiltration was followed by the transient up-regulation of expression of LIFR, IL-6, and IL-6R in ensheathing cells by 3 days post-OBX. The mRNAs for LIF/LIFR, IL-6/IL-6R, and their common signal-transduction molecule, gp130, in olfactory-nasal mucosa from control mice and from 3-day post-OBX mice were detected with reverse transcriptase-polymerase chain reaction (RT-PCR). Analysis of Northern blot and relative quantitative RT-PCR demonstrated similar temporal patterns of changes in relative mRNA levels for both LIF and IL-6, which were up-regulated by 16 hours post-OBX and peaked at 2--3 days post-OBX. These data indicate that LIF from infiltrating macrophages acts as a mitogen for GBCs and that LIF from infiltrating macrophages and IL-6 from infiltrating macrophages and ensheathing cells act as repair factors in the ON.

Accelerated Nerve Regeneration in Mice by upregulated expression of interleukin (IL) 6 and IL-6 receptor after trauma.

In this study we aimed to examine a role for interleukin 6 (IL-6) and its receptor (IL-6R) in peripheral nerve regeneration in vivo. We first observed that cultured mouse embryonic dorsal root ganglia exhibited dramatic neurite extension by simultaneous addition of IL-6 and soluble IL-6R (sIL-6R), a complex that is known to interact with and activate a signal transducing receptor component, gp130. After injury in the hypoglossal nerve in adult mice by ligation, immunoreactivity to IL-6 was upregulated in Schwann cells at the lesional site as well as in the cell bodies of hypoglossal neurons in the brain stem. In the latter, upregulation of the immunoreactivity to IL-6R was also observed. Regeneration of axotomized hypoglossal nerve in vivo was significantly retarded by the administration of anti-IL-6R antibody. Surprisingly, accelerated regeneration of the axotomized nerve was achieved in transgenic mice constitutively expressing both IL-6 and IL-6R, as compared with nontransgenic controls. These results suggest that the IL-6 signal may play an important role in nerve regeneration after trauma in vivo.