The Role of the IL-20 Subfamily in Glaucoma

The interleukin-10 family: Major regulators of the immune response against Plasmodium falciparum infections

Malaria caused by the Plasmodium falciparum strain is more severe because of this protozoan's ability to disrupt the physiology of host cells during the blood stages of development by initiating the production of the interleukin-10 (IL-10) family of cytokines. P. falciparum feeds on hemoglobin and causes host cells to adhere to the walls of blood vessels by remodeling their composition. IL-10 is produced by CD4+ T cells that inhibits antigen-presenting cells' activity to prevent inflammation. This cytokine and its family members are crucial in promoting malarial infection by inhibiting the host's protective immune response, thus initiating Plasmodium parasitemia. IL-10 is also responsible for preventing severe pathology during Plasmodium infection and initiates several signaling pathways to alter the physiology of host cells during malarial infection. This review summarizes the critical aspects of P. falciparum infection, including its role in signaling pathways for cytokine exudation, its effect on microRNA, the human immune response in malaria, and the role played by the liver hormone hepcidin. Moreover, future aspects of vaccine development and therapeutic strategies to combat P. falciparum infections are also discussed in detail.

Molecular genetics of primary open-angle glaucoma

Glaucoma is a series of linked optic diseases resulting in progressive vision loss and total blindness due to the acquired loss of retinal ganglion cells. This harm to the optic nerve results in visual impairment and, ultimately, total blindness if left untreated. Primary open-angle glaucoma (POAG) is the most frequent variety within the large family of glaucoma. It is a multifaceted and heterogeneous condition with several environmental and genetic variables aiding in its etiology. By 2040, there will be 111.8 million glaucoma patients globally, with Asia and Africa accounting for the vast majority. The goal of this review is to elaborate on the role of genes (nuclear and mitochondrial) as well as their variants in the pathogenesis of POAG. PubMed and Google Scholar databases were searched online for papers until September 2022. Prevalence and inheritance patterns vary significantly across different ethnic and geographic populations. Numerous causative genetic loci may exist; however, only a few have been recognized and characterized. Further investigation into the genetic etiology of POAG is expected to uncover novel and intriguing causal genes, allowing for a more precise pathogenesis pattern of the disease.

Grass carp IL-20 binds to IL-20R2 but induces STAT3 phosphorylation via IL-20R1

IL-20 is a pleiotropic cytokine that belongs to the IL-10 family and has a variety of biological functions in tissue homeostasis and regulation of host immune defenses. It signals through a heterodimeric receptor composed of a subunit with a long intracellular domain (R1 type receptor) and a subunit with a short intracellular domain (R2 type receptor). In this study, the R1 type receptor (CiIL-20R1/CRFB8) and the R2 type receptor (CiIL-20R2/CRFB16) were identified in grass carp Ctenopharyngodon idella. Expression analysis revealed that IL-20R2 was highly expressed in the gills and skin in healthy fish. Infection with Flavobacterium columnare resulted in the downregulation of both receptors in the gill at 48 and 72 h, whilst infection with grass carp reovirus induced their expression in the head kidney and spleen at 72 h. In the primary head kidney leucocytes, the expression levels of IL-20R1 and IL-20R2 were decreased after stimulation with 250 ng/mL IL-1β but not affected by IFN-γ. Co-immunoprecipitation analysis showed that CiIL-20R2/CRFB16 but not CiIL-20R1/CRFB8 bound to CiIL-20L. Furthermore, it was shown that CiIL-20R1/CRFB8 was responsible for activating the phosphorylation of STAT3, whilst CiIL-20R2/CRFB16 was not involved. Structural modeling analysis showed that key residues involved in the interaction between IL-20 and receptors were highly conserved between grass carp and humans, suggesting that the signal transduction and functions of IL-20/IL-20R axis are evolutionarily conserved.

Identification of IL20RB as a Novel Prognostic and Therapeutic Biomarker in Clear Cell Renal Cell Carcinoma

Background

Clear cell renal cell carcinoma (ccRCC) is a type of life-threatening malignant tumor of the urinary system. IL20RB, interleukin 20 receptor subunit beta, is a cytokine receptor subunit coding gene and was initially found to play a vital role in human cancers, while its role in ccRCC still remains unclear.

Methods

In this work, we explored the prognostic value and therapeutic potential of IL20RB in ccRCC mainly by online tools. Firstly, we used UALCAN and GEPIA to explore the expression profile and prognostic value of IL20RB in various cancers; the expression profile in tumor cell lines was also analysed with CCLE and Expression Atlas. Then, we decided to focus on ccRCC for further analysis; we further demonstrated the significant correlation between expression and clinical features by GEPIA and UALCAN. In order to reveal the potential intrinsic mechanism responsible for the upregulation of IL20RB in ccRCC, we made genetic alternation analysis and methylation analysis. cBioPortal was used for genetic alternation analysis. UALCAN, MethSurv, and Xena were used for methylation analysis. To learn details of how IL20RB might function in ccRCC, we further conducted functional analysis and immune infiltration analysis. STRING and GSEA were used to do functional analysis. TIMER was used for immune infiltration analysis; KM plotter was used for survival analysis.

Results

Results show that IL20RB is upregulated in ccRCC, and low methylation may be responsible for its upregulation. Both high expression and low methylation of IL20RB predict worse survival, and both have a strong positive correlation with clinical characteristics. In addition, results indicate that there exists a crosstalk between IL20RB and neutrophils. Furthermore, the immune microenvironment could influence the prognosis predicting ability of IL20RB.

Conclusions

In conclusion, IL20RB plays an important role in ccRCC and is identified as a novel prognostic and potential therapeutic biomarker in ccRCC.

Identification of an Immune-Related Gene Signature to Improve Prognosis Prediction in Colorectal Cancer Patients

BACKGROUND

Despite recent advance in immune therapy, great heterogeneity exists in the outcomes of colorectal cancer (CRC) patients. In this study, we aimed to analyze the immune-related gene (IRG) expression profiles from three independent public databases and develop an effective signature to forecast patient's prognosis.

METHODS

IRGs were collected from the ImmPort database. The CRC dataset from The Cancer Genome Atlas (TCGA) database was used to identify a prognostic gene signature, which was verified in another two CRC datasets from the Gene Expression Omnibus (GEO). Gene function enrichment analysis was conducted. A prognostic nomogram was built incorporating the IRG signature with clinical risk factors.

RESULTS

The three datasets had 487, 579, and 224 patients, respectively. A prognostic six-gene-signature (CCL22, LIMK1, MAPKAPK3, FLOT1, GPRC5B, and IL20RB) was developed through feature selection that showed good differentiation between the low- and high-risk groups in the training set (p < 0.001), which was later confirmed in the two validation groups (log-rank p < 0.05). The signature outperformed tumor TNM staging for survival prediction. GO and KEGG functional annotation analysis suggested that the signature was significantly enriched in metabolic processes and regulation of immunity (p < 0.05). When combined with clinical risk factors, the model showed robust prediction capability.

CONCLUSION

The immune-related six-gene signature is a reliable prognostic indicator for CRC patients and could provide insight for personalized cancer management.

Overexpression of interleukin-20 receptor subunit beta (IL20RB) correlates with cell proliferation, invasion and migration enhancement and poor prognosis in papillary renal cell carcinoma

Papillary renal cell carcinoma (PRCC) accounts for about 10 percent of all renal cell carcinomas, and the prognosis is poor for people with advanced disease. Interleukin-20 receptor subunit beta (IL20RB) is a single-pass type I membrane protein of the type II cytokine receptor family and is related to the pathogenesis of chronic inflammation and autoimmune diseases, including psoriasis, glaucoma, vitiligo, rheumatoid arthritis, and inflammatory bowel disease. However, little has been reported on IL20RB with respect to cancer, especially in PRCC. Thus, we performed this study to explore its biological characteristics in PRCC. Data from the TCGA database were used to analyze the expression and prognosis of IL20RB. qRT-PCR was used to detect the expression of IL20RB in PRCC cells in vitro. After knockdown of IL20RB with small interfering RNA (siRNA) technology, the proliferation, migration, and invasion of Ketr-3 cells and the expression of related proteins in the epithelial-mesenchymal transition (EMT) pathway were measured with Cell Counting Kit-8 (CCK-8), transwell, and western blot assays. The findings demonstrated that the expression of IL20RB was upregulated in both PRCC tissues and cells and that the high expression of IL20RB led to low overall survival (OS). Furthermore, after knockdown of IL20RB in vitro, the proliferation, migration, and invasion of Ketr-3 cells were reduced, and the expression of related proteins in the EMT pathway declined, suggesting that IL20RB plays a vital role in PRCC through the EMT pathway. These results reveal the biological significance of IL20RB in PRCC and provide new insight for future targeted drugs.

Investigating a downstream gene of Gpnmb using the systems genetics method

Purpose

Glaucoma is characterized by optic nerve damage and retinal ganglion cell loss. The glycoprotein neuromedin B-associated (Gpnmb) gene is well-known to be involved in the glaucoma disease process. The purpose of this study is to identify a downstream gene through which Gpnmb affects the glaucoma phenotypes using a systems genetics approach.

Methods

Retinal gene expression data for the BXD recombinant inbred (RI) strains (n=75) have previously been generated in our laboratory for a glaucoma study, and these data were used for genetic and bioinformatics analysis. Expression quantitative trait locus (eQTL) mapping and genetic correlation methods were used to identify a gene downstream of Gpnmb. Gene-set enrichment analysis was used to evaluate gene function and to construct coexpression networks.

Results

The level of Gpnmb expression is associated with a highly statistically significant cis-eQTL. Stanniocalcin 1 (Stc1) has a significant trans-eQTL mapping to the Gpnmb locus. The expression of Gpnmb and Stc1 is highly correlated in the retina and other tissues, as well as with glaucoma-related phenotypes. Gene Ontology and pathway analysis showed that Stc1 and its covariates are highly associated with apoptosis, oxidative stress, and mitochondrial activity. A generated gene network indicated that Gpnmb and Stc1 are directly connected to and interact with other genes with similar biologic functions.

Conclusions

These results suggest that Stc1 may be a downstream candidate of Gpnmb, and that both genes interact with other genes in a network to develop glaucoma pathogenesis through mechanisms such as apoptosis and oxidative stress.

IL-20 receptor cytokines in autoimmune diseases

IL-19, IL-20, and IL-24 are the members of IL-10 family. They are also known as IL-20 receptor (IL-20R) cytokines as they all signal through the IL-20RA/IL-20RB receptor complex; IL-20 and IL-24 (but not IL-19) also signal through the IL-20RB/IL22RA1 receptor complex. Despite their protein structure homology and shared use of receptor complexes, they display distinct biological functions in immune regulation, tissue homeostasis, host defense, and oncogenesis. IL-20R cytokines can be expressed by both immune cells and epithelial cells, and are important for their interaction. In general, these cytokines are considered to be associated with pathogenesis of chronic inflammation and autoimmune diseases, including psoriasis, rheumatoid arthritis, and inflammatory bowel disease. However, a number of studies also highlighted their suppressive functions in regulating both innate and adaptive T cell responses and other immune cells, suggesting that the role of IL-20R cytokines in autoimmunity may be complex. In this review, we will discuss the immunobiological functions of IL-20R cytokines and how they are involved in regulating autoimmune diseases.

Research progress on human genes involved in the pathogenesis of glaucoma (Review)

Glaucoma is the leading cause of irreversible blindness globally. It is known that the incidence of glaucoma is closely associated with inheritance. A large number of studies have suggested that genetic factors are involved in the occurrence and development of glaucoma, and even affect the drug sensitivity and prognosis of glaucoma. In the present review, 22 loci of glaucoma are presented, including the relevant genes (myocilin, interleukin 20 receptor subunit B, optineurin, ankyrin repeat- and SOCS box-containing protein 10, WD repeat-containing protein 36, EGF-containing fibulin-like extracellular matrix protein 1, neurotrophin 4, TANK-binding kinase 1, cytochrome P450 subfamily I polypeptide 1, latent transforming growth factor β binding protein 2 and TEK tyrosine kinase endothelial) and 74 other genes (including toll-like receptor 4, sine oculis homeobox Drosophila homolog of 1, doublecortin-like kinase 1, RE repeats-encoding gene, retinitis pigmentosa GTPase regulator-interacting protein, lysyl oxidase-like protein 1, heat-shock 70-kDa protein 1A, baculoviral IAP repeat-containing protein 6, 5,10-methylenetetrahydrofolate reductase and nitric oxide synthase 3 and nanophthalmos 1) that are more closely associated with glaucoma. The pathogenesis of these glaucoma-associated genes, glaucomatous genetics and genetic approaches, as well as glaucomatous risk factors, including increasing age, glaucoma family history, high myopia, diabetes, ocular trauma, smoking, intraocular pressure increase and/or fluctuation were also discussed.

Exploring Landscape of Drug-Target-Pathway-Side Effect Associations

Side effects are the second and the fourth leading causes of drug attrition and death in the US. Thus, accurate prediction of side effects and understanding their mechanism of action will significantly impact drug discovery and clinical practice. Here, we show REMAP, a neighborhood-regularized weighted and imputed one-class collaborative filtering algorithm, is effective in predicting drug-side effect associations from a drug-side effect association network, and significantly outperforms the state-of-the-art multi-target learning algorithm for predicting rare side effects. We also apply FASCINATE, an extension of REMAP for multi-layered networks, to infer associations among side effects and drug targets from drug-target-side effect networks. Then, using random permutation analysis and gene overrepresentation tests, we infer statistically significant side effect-pathway associations. The predicted drug-side effect associations and side effect-causing pathways are consistent with clinical evidences. We expect more novel drug-side effect associations and side effect-causing pathways to be identified when applying REMAP and FASCINATE to large-scale chemical-gene-side effect networks.

Major review: Molecular genetics of primary open-angle glaucoma

Glaucoma is a leading cause of irreversible blindness worldwide. Primary open-angle glaucoma (POAG), the most common type, is a complex inherited disorder that is characterized by progressive retinal ganglion cell death, optic nerve head excavation, and visual field loss. The discovery of a large, and growing, number of genetic and chromosomal loci has been shown to contribute to POAG risk, which carry implications for disease pathogenesis. Differential gene expression analyses in glaucoma-affected tissues as well as animal models of POAG are enhancing our mechanistic understanding in this common, blinding disorder. In this review we summarize recent developments in POAG genetics and molecular genetics research.

Steroid-induced ocular hypertension/glaucoma: Focus on pharmacogenomics and implications for precision medicine

Elevation of intraocular pressure (IOP) due to therapeutic use of glucocorticoids is called steroid-induced ocular hypertension (SIOH); this can lead to steroid-induced glaucoma (SIG). Glucocorticoids initiate signaling cascades ultimately affecting expression of hundreds of genes; this provides the potential for a highly personalized pharmacological response. Studies attempting to define genetic risk factors were undertaken early in the history of glucocorticoid use, however scientific tools available at that time were limited and progress stalled. In contrast, significant advances were made over the ensuing years in defining disease pathophysiology. As the genomics age emerged, it appeared the time was right to renew investigation into genetics. Pharmacogenomics is an unbiased discovery approach, not requiring an underlying hypothesis, and provides a way to pinpoint clinically significant genes and pathways that could not have been discovered any other way. Results of the first genome-wide association study to identify polymorphisms associated with SIOH, and follow-up on two novel genes linked to the disorder, GPR158 and HCG22, is discussed in the second half of the article. However, knowledge of genetic variants determining response to steroids in the eye also has value in its own right as a predictive and diagnostic tool. This article concludes with a discussion of how the Precision Medicine Initiative®, announced by U.S. President Obama in his 2015 State of the Union address, is beginning to touch the practice of ophthalmology. It is argued that SIOH/SIG may provide one of the next opportunities for effective application of precision medicine.