Novel inhibitors for murine and human leukemia inhibitory factor based on fused soluble receptors

Effects of Melatonin, GM-CSF, IGF-1, and LIF in Culture Media on Embryonic Development: Potential Benefits of Individualization

The implantation of good-quality embryos to the receptive endometrium is essential for successful live birth through in vitro fertilization (IVF). The higher the quality of embryos, the higher the live birth rate per cycle, and so efforts have been made to obtain as many high-quality embryos as possible after fertilization. In addition to an effective controlled ovarian stimulation process to obtain high-quality embryos, the composition of the embryo culture medium in direct contact with embryos in vitro is also important. During embryonic development, under the control of female sex hormones, the fallopian tubes and endometrium create a microenvironment that supplies the nutrients and substances necessary for embryos at each stage. During this process, the development of the embryo is finely regulated by signaling molecules, such as growth factors and cytokines secreted from the epithelial cells of the fallopian tube and uterine endometrium. The development of embryo culture media has continued since the first successful human birth through IVF in 1978. However, there are still limitations to mimicking a microenvironment similar to the reproductive organs of women suitable for embryo development in vitro. Efforts have been made to overcome the harsh in vitro culture environment and obtain high-quality embryos by adding various supplements, such as antioxidants and growth factors, to the embryo culture medium. Recently, there has been an increase in the number of studies on the effect of supplementation in different clinical situations such as old age, recurrent implantation failure (RIF), and unexplained infertility; in addition, anticipation of the potential benefits from individuation is rising. This article reviews the effects of representative supplements in culture media on embryo development.

IL-6 Cytokine Family: A Putative Target for Breast Cancer Prevention and Treatment

The IL-6 cytokine family is a group of signaling molecules with wide expression and function across vertebrates. Each member of the family signals by binding to its specific receptor and at least one molecule of gp130, which is the common transmembrane receptor subunit for the whole group. Signal transduction upon stimulation of the receptor complex results in the activation of multiple downstream cascades, among which, in mammary cells, the JAK-STAT3 pathway plays a central role. In this review, we summarize the role of the IL-6 cytokine family—specifically IL-6 itself, LIF, OSM, and IL-11—as relevant players during breast cancer progression. We have compiled evidence indicating that this group of soluble factors may be used for early and more precise breast cancer diagnosis and to design targeted therapy to treat or even prevent metastasis development, particularly to the bone. Expression profiles and possible therapeutic use of their specific receptors in the different breast cancer subtypes are also described. In addition, participation of these cytokines in pathologies of the breast linked to lactation and involution of the gland, as post-partum breast cancer and mastitis, is discussed.

An engineered ligand trap inhibits leukemia inhibitory factor as pancreatic cancer treatment strategy

Leukemia inhibitory factor (LIF), a cytokine secreted by stromal myofibroblasts and tumor cells, has recently been highlighted to promote tumor progression in pancreatic and other cancers through KRAS-driven cell signaling. We engineered a high affinity soluble human LIF receptor (LIFR) decoy that sequesters human LIF and inhibits its signaling as a therapeutic strategy. This engineered 'ligand trap', fused to an antibody Fc-domain, has ~50-fold increased affinity (~20 pM) and improved LIF inhibition compared to wild-type LIFR-Fc, potently blocks LIF-mediated effects in pancreatic cancer cells, and slows the growth of pancreatic cancer xenograft tumors. These results, and the lack of apparent toxicity observed in animal models, further highlights ligand traps as a promising therapeutic strategy for cancer treatment.

Prognostic modeling of the immune-centric transcriptome reveals interleukin signaling candidates contributing to differential patient outcomes

Immunotherapy is a promising advancement in the treatment of non-small-cell lung carcinoma (NSCLC), although much of how lung tumors interact with the immune system in the natural course of disease remains unknown. We investigated the impact of the expression of immune-centric genes and pathways in tumors on patient survival to reveal novel candidates for immunotherapeutic research. Tumor transcriptomes and detailed clinical characteristics were obtained from patients with NSCLC who were participants of either the Inflammation, Health and Lung Epidemiology (INHALE) (discovery, N = 280) or The Cancer Genome Atlas (TCGA) Lung (replication, N = 1026) studies. Expressions of 2253 genes derived from 48 major immune pathways were assessed for association with patient prognosis using a multivariable Cox model and pathway effects were assessed with an in-house implementation of the Gene Set Enrichment Analysis (GSEA) algorithm. Prognosis-guided gene and pathway analysis of immune-centric expression in tumors revealed significant survival enrichments across both cohorts. The 'Interleukin Signaling' pathway, containing 430 genes, was found to be statistically and significantly enriched with prognostic signal in both the INHALE (P = 0.008) and TCGA (P = 0.039) datasets. Subsequent leading-edge analysis identified a subset of genes (N = 23) shared between both cohorts, driving the pathway enrichment. Cumulative expression of this leading-edge gene signature was a strong predictor of patient survival [discovery: hazard ratio (HR) = 1.59, P = 3.0 × 10-8; replication: HR = 1.29, P = 7.4 × 10-7]. These data demonstrate the impact of immune-centric expression on patient outcomes in NSCLC. Furthermore, prognostic gene effects were localized to discrete immune pathways, of which Interleukin Signaling had the greatest impact on overall survival and the subset of genes driving these effects have promise for future therapeutic intervention.

Electroporation-mediated delivery of FER gene enhances innate immune response and improves survival in a murine model of pneumonia

Previously, we reported that electroporation-mediated (EP) delivery of the FER gene improved survival in a combined trauma-pneumonia model. The mechanism of this protective effect is unknown. In this paper, we performed a pneumonia model in C57/BL6 mice with 500 CFU of Klebsiella pneumoniae. After inoculation, a plasmid encoding human FER was delivered by EP into the lung (PNA/pFER-EP). Survival of FER-treated vs. controls (PNA; PNA/EP-pcDNA) was recorded. In parallel cohorts, bronchial alveolar lavage (BAL) and lung were harvested at 24 and 72 h with markers of infection measured. FER-EP-treated animals reduced bacterial counts and had better 5-day survival compared to controls (80 vs. 20 vs. 25%; p < 0.05). Pre-treatment resulted in 100% survival. With FER, inflammatory monocytes were quickly recruited into BAL. These cells had increased surface expression for Toll-receptor 2 and 4, and increased phagocytic and myeloperoxidase activity at 24 h. Samples from FER electroporated animals had increased phosphorylation of STAT transcription factors, varied gene expression of IL1β, TNFα, Nrf2, Nlrp3, Cxcl2, HSP90 and increased cytokine production of TNF-α, CCL-2, KC, IFN-γ, and IL-1RA. In a follow-up experiment, using Methicillin-resistant Staphylococcus aureus (MRSA) similar bacterial reduction effects were obtained with FER gene delivery. We conclude that FER overexpression improves survival through STAT activation enhancing innate immunity and accelerating bacterial clearance in the lung. This constitutes a novel mechanism of inflammatory regulation with therapeutic potential in the setting of hospital-acquired pneumonia.

High LIFr expression stimulates melanoma cell migration and is associated with unfavorable prognosis in melanoma

Increased or decreased expression of LIF receptor (LIFr) has been reported in several human cancers, including skin cancer, but its role in melanoma is unknown. In this study, we investigated the expression pattern of LIFr in melanoma and assessed its prognostic value. Using tissue microarrays consisting of 441 melanomas and 96 nevi, we found that no normal nevi showed high LIFr expression. LIFr staining was significantly increased in primary melanoma compared to dysplastic nevi (P = 0.0003) and further increased in metastatic melanoma (P = 0.0000). Kaplan–Meier survival curve and univariate Cox regression analyses showed that increased expression of LIFr was correlated with poorer 5-year patient survival (overall survival, P = 0.0000; disease-specific survival, P = 0.0000). Multivariate Cox regression analyses indicated that increased LIFr expression was an independent prognostic marker for primary melanoma (P = 0.036). LIFr knockdown inhibited melanoma cell migration in wound healing assays and reduced stress fiber formation. LIFr knockdown correlated with STAT3 suppression, but not YAP, suggesting that LIFr activation might stimulate melanoma cell migration through the STAT3 pathway. Our data indicate that strong LIFr expression identifies potentially highly malignant melanocytic lesions at an early stage and LIFr may be a potential target for the development of early intervention therapeutics.

Anti-interleukin-6 therapy through application of a monogenic protein inhibitor via gene delivery

Anti-cytokine therapies have substantially improved the treatment of inflammatory and autoimmune diseases. Cytokine-targeting drugs are usually biologics such as antibodies or other engineered proteins. Production of biologics, however, is complex and intricate and therefore expensive which might limit therapeutic application. To overcome this limitation we developed a strategy that involves the design of an optimized, monogenic cytokine inhibitor and the protein producing capacity of the host. Here, we engineered and characterized a receptor fusion protein, mIL-6-RFP-Fc, for the inhibition of interleukin-6 (IL-6), a well-established target in anti-cytokine therapy. Upon application in mice mIL-6-RFP-Fc inhibited IL-6-induced activation of the transcription factor STAT3 and ERK1/2 kinases in liver and kidney. mIL-6-RFP-Fc is encoded by a single gene and therefore most relevant for gene transfer approaches. Gene transfer through hydrodynamic plasmid delivery in mice resulted in hepatic production and secretion of mIL-6-RFP-Fc into the blood in considerable amounts, blocked hepatic acute phase protein synthesis and improved kidney function in an ischemia and reperfusion injury model. Our study establishes receptor fusion proteins as promising agents in anti-cytokine therapies through gene therapeutic approaches for future targeted and cost-effective treatments. The strategy described here is applicable for many cytokines involved in inflammatory and other diseases.

Insights into IL-23 biology: From structure to function

Interleukin (IL-)23 is a central cytokine controlling TH17 development. Overshooting IL-23 signaling contribute to autoimmune diseases. Moreover, GWAS studies have identified several SNPs within the IL-23 receptor, which are associated with autoimmune diseases. IL-23 is a member of the IL-12-type cytokine family and consists of IL-23p19 and p40. Within the IL-12 family, IL-12 and IL-23 share the p40 cytokine subunit and the IL-12Rβ1 as one chain of the receptor complex. For signaling, IL-23 triggers heterodimerization of IL-12Rβ1 and the IL-23R. Subsequently, signal transduction pathways including JAK/STAT, MAPK and PI3K are activated. Most studies have investigated the biological relevance of IL-23 in the development of TH17 cells and autoimmunity, whereas less is known about the molecular context of IL-23 biology. Therefore, we focused on IL-23 receptor complex assembly, signal transduction and functional relevance of IL-23R SNPs in the context of IL-23-inhibitory principles.

Leukemia inhibitory factor: roles in embryo implantation and in nonhormonal contraception

Leukaemia inhibitory factor (LIF) plays an indispensible role in embryo implantation. Aberrant LIF production is linked to implantation failure. LIF regulates multiple processes prior to and during implantation such as uterine transformation into a receptive state, decidualization, blastocyst growth and development, embryo-endometrial interaction, trophoblast invasion, and immune modulation. Due to its critical role, LIF has been a target for a nonhormonal contraception. In this review, we summarize up-to-date information on the role of LIF in implantation and its role in contraception.

Correlation between serum interleukin-31 level and the severity of disease in children with atopic dermatitis

Introduction

Atopic dermatitis (AD) is a chronic inflammatory skin disease, characterized by intense itch, typical localization and a specific image of skin lesions. Pathogenesis of pruritus in AD is not fully understood, but recent studies emphasize the role of interleukin-31 (IL-31). This relatively recently described cytokine is considered to be a potential mediator inducing pruritus in AD.

Aim

To assess the correlation of serum IL-31 level and the disease severity in children with AD.

Material and methods

Twenty-five children (16 girls and 9 boys) with AD aged from 4 months to 17 years (mean age: 4.2 years) were enrolled in the study. Disease severity in children with AD was assessed using the SCORAD (Severity SCORing of Atopic Dermatitis) index. Serum IL-31 levels were measured using ELISA with standard kits from EIAab R&D Systems.

Results

Serum IL-31 level was significantly higher in AD children than in healthy children. There was no statistic correlation between serum IL-31 level and the disease severity or itch intensity.

Conclusions

The disease severity and itch intensity do not correlate with serum IL-31 level in children with atopic dermatitis.

A receptor fusion protein for the inhibition of murine oncostatin M

Background

Most cytokines signal through heteromeric receptor complexes consisting of two or more different receptor subunits. Fusion proteins of the extracellular parts of receptor subunits turned out to be promising cytokine inhibitors useful in anti-cytokine therapy and cytokine research.

Results

We constructed receptor fusion proteins (RFP) consisting of the ligand binding domains of the murine oncostatin M (mOSM) receptor subunits mOSMR and mgp130 connected by a flexible linker as potential mOSM inhibitors. mgp130 is a shared cytokine receptor that is also used by other cytokines such as IL-6 and leukemia inhibitory factor (LIF). In this study we compare four types of mOSM-RFPs that contain either domains D1-D3 or domains D2-D3 of mgp130 and are arranged in two ways. Domain D1 of mgp130 turned out to be dispensable for mOSM-binding. However, the arrangement of the two receptor subunits is essential for the inhibitory activity. We found mOSM induced STAT3 phosphorylation to be suppressed only when the mOSMR fragment was fused in front of the mgp130 fragment.

Conclusions

mOSM-RFP consisting of D1-D4 of mOSMR and D2-D3 of mgp130 is a highly potent and specific inhibitor of mOSM. Since mOSM-RFP is encoded by a single gene it offers numerous possibilities for specific cytokine inhibition in gene delivery approaches based on viral vectors, transgenic animals and finally gene therapy.

Anticancer efficacy of a difluorodiarylidenyl piperidone (HO-3867) in human ovarian cancer cells and tumor xenografts

The purpose of this study was to evaluate the anticancer potency and mechanism of a novel difluorodiarylidenyl piperidone (H-4073) and its N-hydroxypyrroline modification (HO-3867) in human ovarian cancer. Studies were done using established human ovarian cancer cell lines (A2870, A2780cDDP, OV-4, SKOV3, PA-1, and OVCAR3) as well as in a murine xenograft tumor (A2780) model. Both compounds were comparably and significantly cytotoxic to A2780 cells. However, HO-3867 showed a preferential toxicity toward ovarian cancer cells while sparing healthy cells. HO-3867 induced G(2)-M cell cycle arrest in A2780 cells by modulating cell cycle regulatory molecules p53, p21, p27, cyclin-dependent kinase 2, and cyclin, and promoted apoptosis by caspase-8 and caspase-3 activation. It also caused an increase in the expression of functional Fas/CD95 and decreases in signal transducers and activators of transcription 3 (STAT3; Tyr705) and JAK1 phosphorylation. There was a significant reduction in STAT3 downstream target protein levels including Bcl-xL, Bcl-2, survivin, and vascular endothelial growth factor, suggesting that HO-3867 exposure disrupted the JAK/STAT3 signaling pathway. In addition, HO-3867 significantly inhibited the growth of the ovarian xenografted tumors in a dosage-dependent manner without any apparent toxicity. Western blot analysis of the xenograft tumor tissues showed that HO-3867 inhibited pSTAT3 (Tyr705 and Ser727) and JAK1 and increased apoptotic markers cleaved caspase-3 and poly ADP ribose polymerase. HO-3867 exhibited significant cytotoxicity toward ovarian cancer cells by inhibition of the JAK/STAT3 signaling pathway. The study suggested that HO-3867 may be useful as a safe and effective anticancer agent for ovarian cancer therapy.

Definition and characterization of an inhibitor for interleukin-31

Interleukin-31 (IL-31) is a recently described T cell-derived cytokine, mainly produced by T helper type 2 cells and related to the IL-6 cytokine family according to its structure and receptor. IL-31 is the ligand for a heterodimeric receptor composed of a gp130-like receptor (GPL) associated with the oncostatin M receptor (OSMR). A link between IL-31 and atopic dermatitis was shown by studying the phenotype of IL-31 transgenic mice and IL-31 gene haplotypes in patients suffering from dermatitis. In this study, we generated a potent IL-31 antagonist formed by external portions of OSMR and GPL fused with a linker. This fusion protein, OSMR-L-GPL, consisting of 720 amino acids, counteracted the binding of IL-31 to its membrane receptor complex and the subsequent signaling events involving the STATs and MAPK pathways. Neutralizing effects were found in IL-31-sensitive cell lines, including brain-derived cells and primary cultures of keratinocytes.

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.