Podoplanin expression in wound and hyperproliferative psoriatic epidermis: regulation by TGF-β and STAT-3 activating cytokines, IFN-γ, IL-6, and IL-22

Human lymph node fibroblastic reticular cells maintain heterogeneous characteristics in culture

Fibroblastic reticular cells (FRCs) are mesenchymal stromal cells in human lymph nodes (LNs) playing a pivotal role in adaptive immunity. Several FRC subsets have been identified, yet it remains to be elucidated if their heterogeneity is maintained upon culture. Here, we established a protocol to preserve and culture FRCs from human LNs and characterized their phenotypic profile in fresh LN suspensions and upon culture using multispectral flow cytometry. We found nine FRC subsets in fresh human LNs, independent of donor, of which four persisted in culture throughout several passages. Interestingly, the historically FRC-defining marker podoplanin (PDPN) was not present on all FRC subsets. Therefore, we propose that CD45negCD31neg human FRCs are not restricted by PDPN expression, as we found CD90, BST1, and CD146/MCAM to be more widely expressed. Together, our data provide insight into FRC heterogeneity in human LNs, enabling further investigation into the function of individual FRC subsets.

Uridine phosphorylase-1 promotes cell viability and cell-cycle progression in human epidermal keratinocytes via the glycolytic pathway

Glycolysis is vital for the excessive proliferation of keratinocytes in psoriasis, and uridine phosphorylase-1 (UPP1) functions as an enhancer of cancer cell proliferation. However, little is known about whether UPP1 promotes keratinocyte proliferation and accelerates psoriasis development. This study revealed that UPP1 facilitates cell viability and cell-cycle progression in human epidermal keratinocytes (HEKs) by modulating the glycolytic pathway. Bioinformatics analysis of UPP1 gene expression and its correlation with the Reactome revealed that UPP1 mRNA expression, cell-cycle progression, the interleukin-6 (IL-6)/Janus kinase (JAK)/signal transducer and activator of transcription 3 (STAT3) pathway and glycolysis were positively associated with psoriasis. Cell proliferation, the cell cycle and glycolysis were evaluated after UPP1 was silenced or overexpressed. The results showed that UPP1 overexpression increased cell proliferation, cell-cycle progression and glycolysis, which was contrary to the effects of UPP1 silencing. However, the STAT3 inhibitor diminished UPP1 expression because STAT3 can bind to the UPP1 promoter. In conclusion, UPP1 was significantly activated by the IL-6/STAT3 pathway and could modulate glycolysis to regulate cell proliferation and cell-cycle progression in keratinocytes during the development of psoriasis.

Stromal-Like Cells Are Found in Peripheral Blood of Patients With Inflammatory Bowel Disease and Correlate With Immune Activation State

INTRODUCTION

Recent studies have identified a critical role of stromal-immune cell interactions in immunity and immune tolerance. Transcriptomic profiling has implicated stromal cells in immune-mediated disorders including the 2 common forms of inflammatory bowel disease (IBD), Crohn's disease (CD), and ulcerative colitis (UC). Stromal-immune interactions may edify inflammatory state and the development of IBD-related complications such as fibrosis, yet the lack of protein markers has hampered studying stromal-immune perturbation.

METHODS

In this study, we designed a 40-color spectral flow cytometry assay to characterize hematopoietic and nonhematopoietic cells in intestinal biopsies and matched blood samples from patients with CD or UC.

RESULTS

We identified circulating stromal-like cells that are significantly more abundant in IBD blood samples than in healthy controls. Those cells expressed podoplanin (PDPN), a commonly used marker for fibroblasts, and they were associated with activated and memory T and B cells and altered natural killer cell, monocyte, and macrophage populations. PDPN + cells in the blood correlated with PDPN + cells in the colon. Principal component analysis distinctly separated healthy blood samples from IBD blood samples, with stromal-like cells and B-cell subtypes dominating the IBD signature; Pearson correlation detected an association between PDPN + stromal-like cells and B-cell populations in IBD blood and gut biopsies.

DISCUSSION

These observations suggest that PDPN + cells in the blood may serve as a biomarker of IBD. Understanding the relationship between stromal cells and immune cells in the intestine and the blood may provide a window into disease pathogenesis and insight into therapeutic targets for IBD.

Comparative Gene-Expression Analysis of the Ligamentum Flavum of Patients with Lumbar Spinal Canal Stenosis: Comparison between the Dural and Dorsal Sides of the Thickened Ligamentum Flavum

Thickening of the ligamentum flavum is the main factor in the development of lumbar spinal canal stenosis (LSCS). Although previous studies have reported factors related to ligamentum flavum thickening, its etiology has not been clarified. Furthermore, it is often difficult to set proper controls to investigate the pathologies of thickening due to differences in patient characteristics, such as age, sex, obesity, and comorbidities. This study aimed to elucidate the pathologies of ligamentum flavum thickening by comparing the dural and dorsal sides of the thickened ligamentum flavum in patients with LSCS. Ligamentum flavum samples were collected from 19 patients with LSCS. The samples were divided into the dural and dorsal sides. The dural side was used as a control to assess the pathologies occurring on the dorsal side. Elastic Masson staining was used to assess the elastic fibres. Gene expression levels were comprehensively assessed using quantitative reverse transcription polymerase chain reaction and DNA microarray analyses. Gene ontology analysis was used to identify biological processes associated with differentially expressed genes. The elastic fibres were significantly decreased on the dorsal side of the thickened ligamentum flavum. Genes related to fibrosis, inflammation, tissue repair, remodeling, and chondrometaplasia, such as COL1A2, COL3A1, COL5A1, TGFB1, VEGFA, TNFA, MMP2, COL10A1, and ADAMTS4, were highly expressed on the dorsal side of the thickened ligamentum flavum. The biological processes occurring on the dorsal side of the thickened ligamentum flavum were extracellular matrix organization, cell adhesion, extracellular matrix disassembly, and proteolysis.These are considered important pathologies of ligamentum flavum thickening.

JAK/STAT Inhibition Normalizes Lipid Composition in 3D Human Epidermal Equivalents Challenged with Th2 Cytokines

Derangement of the epidermal barrier lipids and dysregulated immune responses are key pathogenic features of atopic dermatitis (AD). The Th2-type cytokines interleukin IL-4 and IL-13 play a prominent role in AD by activating the Janus Kinase/Signal Transduction and Activator of Transcription (JAK/STAT) intracellular signaling axis. This study aimed to investigate the role of JAK/STAT in the lipid perturbations induced by Th2 signaling in 3D epidermal equivalents. Tofacitinib, a low-molecular-mass JAK inhibitor, was used to screen for JAK/STAT-mediated deregulation of lipid metabolism. Th2 cytokines decreased the expression of elongases 1, 3, and 4 and serine-palmitoyl-transferase and increased that of sphingolipid delta(4)-desaturase and carbonic anhydrase 2. Th2 cytokines inhibited the synthesis of palmitoleic acid and caused depletion of triglycerides, in association with altered phosphatidylcholine profiles and fatty acid (FA) metabolism. Overall, the ceramide profiles were minimally affected. Except for most sphingolipids and very-long-chain FAs, the effects of Th2 on lipid pathways were reversed by co-treatment with tofacitinib. An increase in the mRNA levels of CPT1A and ACAT1, reduced by tofacitinib, suggests that Th2 cytokines promote FA beta-oxidation. In conclusion, pharmacological inhibition of JAK/STAT activation prevents the lipid disruption caused by the halted homeostasis of FA metabolism.

METTL14 promotes IL-6-induced viability, glycolysis and inflammation in HaCaT cells via the m6A modification of TRIM27

Interleukin-6 (IL-6) is a cytokine generated by healthy constituents of the skin, but is also up-regulated by a wide range of skin lesions and inflammatory conditions to trigger cytopathy of skin cells. TRIM27 was identified to contribute to the functional effects of IL-6 on skin cells. However, the underlying mechanism was not clear. Lentivirus infection was used for gene overexpression or silencing. RT-PCR and Western blot were used to respectively assess mRNA and protein levels. Cell viability was assessed by CCK-8 assay. Extracellular flux analysis was used to assess the levels of oxygen consumption rate and extracellular acidification rate. Mouse back skin was treated with imiquimod to produce psoriasis-like inflammation in vivo. Histological assessment and immunohistochemistry staining were respectively applied to analyse lesioned mouse and human skin samples. IL-6-induced increased viability, glycolysis and inflammation in keratinocytes was inhibited both by a chemical methylation inhibitor and by METTL14 knockdown. Further investigation found that METTL14 induces m6A methylation of TRIM27, which is recognized by a m6A reader, IGF2BP2. Elevation of TRIM27 level and activation of IL-6/STAT3 signalling pathway were found in an in vivo psoriasis-like inflammation model, whereas inhibition m6A methylation strongly alleviated the inflammation. Finally, METTL14, TRIM27, STAT3, p-STAT3 and IL-6 expressions were all found to be increased in clinical skin samples of psoriatic patients. Our results unravelled METTL14/TRIM27/IGF2BP2 signalling axis in keratinocyte cytopathy, which plays a critical role in facilitating the activation of IL-6/STAT3 signalling pathway. Our findings should provide inspirations for the design of new therapeutics for skin inflammatory diseases including psoriasis.

A circular RNA activated by TGFβ promotes tumor metastasis through enhancing IGF2BP3-mediated PDPN mRNA stability

Metastasis is the leading cause of cancer-related death, where TGFβ-induced epithelial-mesenchymal transition (EMT) process confers on cancer cells increased metastatic potential. However, the involvement of circRNAs in this process is still obscure. Here, we identify a TGFβ-induced circRNA called circITGB6 as an indispensable factor during the TGFβ-mediated EMT process. circITGB6 is significantly upregulated in metastatic cancer samples and its higher abundance is closely correlated to worse prognosis of colorectal cancer (CRC) patients. Through gain- and loss-of-function assays, circITGB6 is found to potently promote EMT process and tumor metastasis in various models in vitro and in vivo. Mechanistically, circITGB6 enhances the mRNA stability of PDPN, an EMT-promoting gene, by directly interacting with IGF2BP3. Notably, interfering circITGB6 with PEI-coated specific siRNA effectively represses liver metastasis. Therefore, our study reveals the function of a TGFβ-regulated circRNA in tumor metastasis and suggests that targeting circITGB6 is a promising strategy for cancer therapy.

JAK-STAT inhibitors in Immune mediated diseases: An Overview

For any biological response, transmission of extracellular signals to the nucleus is required for DNA transcription and gene expression. In that respect, cytokines/chemokines are well-known inflammatory agents which play a critical role in signalling pathways by activating the Janus kinase-signal transducers and activators of transcription (JAK-STAT) signalling proteins (Janus kinase-signal transducers and activators of transcription) which are a group of intracellular kinase molecules. Cytokines are a category of small proteins (∼5-25 kDa) that play a major role in cell signalling and are major drivers of an autoimmune response. Here we will discuss the role of Janus kinase-signal transducers and activators of transcription kinase cascades in the inflammatory-proliferative cascades of autoimmune disease and about the recent progress in the development of oral synthetic Janus kinase inhibitors (JAKi) and their therapeutic efficacies in dermatologic and systemic autoimmune diseases. Therapeutic efficacy of Janus kinase inhibitors is now well established in the treatment of array of autoimmune and inflammatory disease: spondylarthritis with a special focus on psoriatic arthritis (PsA) and its dermatologic manifestations (psoriasis) and ankylosing spondylitis (AS), atopic dermatitis (AD), alopecia areata (AA), rheumatoid arthritis (RA) and inflammatory bowel disease (IBD). In addition to the first-generation Janus kinase inhibitors several new-generation Janus kinase inhibitors are currently being evaluated. It is expected that these Janus kinase inhibitors likely have higher potency and less adverse effects as compared to their predecessors. Here we have discussed: (1) the functional significance of the Janus kinase-signal transducers and activators of transcription kinase cascades in the inflammatory-proliferative processes of autoimmune diseases and its cellular/molecular mechanisms and (2) progress in the development of oral synthetic Janus kinase inhibitors and their therapeutic efficacies in several systemic and cutaneous autoimmune diseases.

Carambolaside W Inhibited H1N1 Influenza Virus-Induced Oxidative Stress through STAT-3/BCL-XL Signaling Pathway

The H1N1 influenza virus is highly infectious and pathogenic, and in recent years, it has often presented seasonal mass outbreaks of infection. People infected with H1N1 will develop a high fever and other respiratory infection symptoms. If not treated in time, complications such as pneumonia may occur. In this study, we focused on developing drugs that can effectively fight against with H1N1 virus. A flavonoid glycoside was extracted from the carambola, then characterized by HR-ESI-MS with the molecular formula C47H58O2, and named carambolaside W. The flavonoid glycosides were found to have good anti-H1N1 influenza virus effects. In this study, we verified that carambolaside W has low toxicity and can effectively inhibit influenza virus replication in vitro. H1N1 virus infection induces intracellular oxidative stress damage to accelerate disease progression. The results showed that carambolaside W effectively inhibited the oxidative stress caused by H1N1 infection. The Western blot assay also revealed that carambolaside W alters the expression of apoptosis-related proteins in vitro and exerts a good anti-H1N1 influenza virus effect. In summary, carambolaside W is a low-toxicity natural flavonoid that can effectively treat the H1N1 influenza virus as a potential anti-H1N1 virus agent.

Psoriasis: Striving for Potential Biomarkers

Psoriasis is a chronic disease that is caused by multiple factors and is identified by itchiness, unpleasant, red, or white scaly patches on the skin, particularly on regularly chafed body regions such as the lateral areas of the limbs. Reports suggest that globally around 2%-3% of the population suffers from psoriasis. In this review, we have discussed the clinical classification of psoriasis and also the ideal characteristics of the biomarkers. An overview regarding the discovery of the biomarker and method for validating the study has been discussed. A growing body of research suggests a link to certain other systemic symptoms such as cardiovascular disorder, metabolic syndrome, and few other comorbidities such as hypertension and nonalcoholic fatty liver disease. Natural killer (NK) cells are lymphocyte cells that concentrate on the destruction of virally infected and malignant cells; these tend to produce a wide range of inflammatory cytokines, some of which are associated with the etiology of psoriasis. Detailed information on the molecular pathogenesis of psoriasis in which interleukin (IL)-17, IL-23, tumor necrosis factor-α (TNF-α), and CCL20 play a very significant role in the development of psoriasis. In this review, we have discussed an overview of the recent state of the biomarkers available for the diagnosis and treatment of psoriasis by emphasizing on the available biomarkers such as epigenomic, transcriptomic, glycomic, and metabolomic. The most recent advancements in molecular-targeted therapy utilizing biologics and oral systemic therapy (methotrexate, apremilast) enable to adequately treat the most serious psoriatic symptoms and also the studies have validated the efficacy of biologic therapy such as TNF-α antagonist (infliximab, adalimumab), IL-23 antagonist (guselkumab, risankizumab), and IL-17 antagonist (secukinumab, ixekizumab). Finally, an overview about the technological opportunities as well as various challenges has been discussed.

Janus kinase inhibitors for the treatment of psoriatic arthritis

Psoriatic arthritis (PsA), a systemic disease, has multi-domain musculoskeletal pathologies along with dermatological manifestations. The current recommendations and the standard of care for the treatment of PsA is to address the domain-based pathologies and the disease severity of the six clinical domains unique to PsA, namely, arthritis of the large and small joints, skin involvement, nail involvement enthesitis, dactylitis and axial disease. With currently available therapies, there are good numbers of primary/secondary non-responders and there are added concerns because of intolerance and adverse effects. In that respect, JAK/STAT inhibitors bring new options for many such patients with psoriasis and PsA. Here, we will discuss currently approved JAK inhibitors for PsA and the others which are in different phases of development, including the TYK2 inhibitors.

Interleukin-22 facilitates the interferon-λ-mediated production of tripartite motif protein 25 to inhibit replication of duck viral hepatitis A virus type 1

The innate immune system provides a defense against invading pathogens by inducing various interferon (IFN)-stimulated genes (ISGs). We recently reported that tripartite motif protein 25 (TRIM25), an important ISG, was highly upregulated in duck embryo hepatocyte cells (DEFs) after infection with duck viral hepatitis A virus type 1 (DHAV-1). However, the mechanism of upregulation of TRIM25 remains unknown. Here we reported that interleukin-22 (IL-22), whose expression was highly facilitated in DEFs and various organs of 1-day-old ducklings after DHAV-1 infection, highly enhanced the IFN-λ-induced production of TRIM25. The treatment with IL-22 neutralizing antibody or the overexpression of IL-22 highly suppressed or facilitated TRIM25 expression, respectively. The phosphorylation of signal transducer and activator of transcription 3 (STAT3) was crucial for the process of IL-22 enhancing IFN-λ-induced TRIM25 production, which was suppressed by WP1066, a novel inhibitor of STAT3 phosphorylation. The overexpression of TRIM25 in DEFs resulted in a high production of IFNs and reduced DHAV-1 replication, whereas the attenuated expression of IFNs and facilitated replication of DHAV-1 were observed in the RNAi group, implying that TRIM25 defended the organism against DHAV-1 propagation by inducing the production of IFNs. In summary, we reported that IL-22 activated the phosphorylation of STAT3 to enhance the IFN-λ-mediated TRIM25 expression and provide a defense against DHAV-1 by inducing IFN production.

Topical VX-509 attenuates psoriatic inflammation through the STAT3/FABP5 pathway in keratinocytes

BACKGROUND

Psoriasis is a chronic inflammatory disease, with lesions mainly manifesting as scaly erythematous plaques. The mild or moderate of psoriasis is the main type of patients in hospital, and topical application remains the preferred treatment option for psoriasis therapy, therefore, the development of novel topical agents has an essential role in psoriasis therapy.

OBJECTIVE

To identify potential drugs for psoriasis topical treatment.

METHODS

We performed drug screening by Imiquimod (IMQ)-induced psoriatic like inflammation in mouse model, followed mouse epidermis by RNA-seq to find the key molecules affecting the drug. The qRT-PCR, WB were performed to test mRNA and protein expression, and Chip assay had been conducted to examine Stat3 bound to promoter of FABP5.

RESULTS

In this study, we identified VX-509, which topical application significantly attenuated IMQ-induced psoriatic like inflammation in mouse model. And then, we verified Epidermal Fatty acid binding protein (E-FABP/FABP5) was significantly decreased in VX-509 treated mouse epidermis by RNA-seq. FABP5 is a key molecule in lipid metabolism, administration of FABP5 inhibitor or knock down of FABP5 expression remarkably abrogated psoriatic inflammation as well as lipid metabolism. Mechanistically, our finding showed that VX-509 blocked IL-22 induced signaling pathway, particular in activation of Stat3. Furthermore, we identified Stat3 is a transcriptional factor associated with FABP5 promoters and VX-509 treatment remarkably attenuated IL-22-induced FABP5 expression through Stat3 in KCs.

CONCLUSIONS

This study demonstrated administration of VX-509 is a potential promising topical drug for treatment of psoriasis, FABP5 is a critical targeted molecule in psoriasis therapy.

The Role of Podoplanin in Skin Diseases

Podoplanin is a sialomucin-like type I transmembrane receptor glycoprotein that is expressed specifically in lymphatic vessels, sebaceous glands, and hair follicles in normal skin. However, under pathological conditions podoplanin expression is upregulated in various cells, such as keratinocytes, fibroblasts, tumor cells, and inflammatory cells, and plays pivotal roles in different diseases. In psoriasis, podoplanin expression is induced in basal keratinocytes via the JAK-STAT pathway and contributes toward epidermal hyperproliferation. Podoplanin expression on keratinocytes can also promote IL-17 secretion from lymphocytes, promoting chronic inflammation. During wound healing, the podoplanin/CLEC-2 interaction between keratinocytes and platelets regulates re-epithelialization at the wound edge. In skin cancers, podoplanin expresses on tumor cells and promotes their migration and epithelial-mesenchymal transition, thereby accelerating invasion and metastasis. Podoplanin is also expressed in normal peritumoral cells, such as cancer-associated fibroblasts in melanoma and keratinocytes in extramammary Paget's disease, which promote tumor progression and predict aggressive behavior and poor prognosis. This review provides an overview of our current understanding of the mechanisms via which podoplanin mediates these pathological skin conditions.

Expression of p53, p63, podoplanin and Ki-67 in recurring versus non-recurring oral leukoplakia

Oral leukoplakia (OL), a potentially malignant disorder, recurs in 40% of cases after surgical removal. Recurrence is a risk factor for malignant transformation. We aimed to examine the prognostic significance of four biomarkers related to cell proliferation: p53, p63, podoplanin (PDPN) and Ki-67 in predicting recurrence. Formalin-fixed-paraffin-embedded specimens from excised OL (n = 73, 33 recurrent; 40 non-recurrent) were collected in a prospective study. Immunohistochemistry was used to visualise expression of p53, p63, PDPN and Ki-67. Image analysis software was used for quantification of p53-, p63- and Ki-67-expressing cells, while PDPN was analysed visually. The expression of all four proteins were higher in recurrent compared with non-recurrent OL, only expression of p53 was statistically significant. In uni- and multivariable Cox regression analyses of individual markers, expression of p63 was significantly associated with higher recurrence risk (p = 0.047). OL with a combined high expression of both p53 and p63 had a significantly higher risk to recur [Log Rank, p = 0.036; multivariate Cox, HR: 2.48 (1.13–5.44; p = 0.024)]. Combination of p53 and p63 expression may be used as a prognostic biomarker for recurrence of OL.

Molecular Pathogenesis of Psoriasis and Biomarkers Reflecting Disease Activity

Psoriasis is a chronic inflammatory skin disease induced by multifactorial causes and is characterized by bothersome, scaly reddish plaques, especially on frequently chafed body parts, such as extensor sites of the extremities. The latest advances in molecular-targeted therapies using biologics or small-molecule inhibitors help to sufficiently treat even the most severe psoriatic symptoms and the extra cutaneous comorbidities of psoriatic arthritis. The excellent clinical effects of these therapies provide a deeper understanding of the impaired quality of life caused by this disease and the detailed molecular mechanism in which the interleukin (IL)-23/IL-17 axis plays an essential role. To establish standardized therapeutic strategies, biomarkers that define deep remission are indispensable. Several molecules, such as cytokines, chemokines, antimicrobial peptides, and proteinase inhibitors, have been recognized as potent biomarker candidates. In particular, blood protein markers that are repeatedly measurable can be extremely useful in daily clinical practice. Herein, we summarize the molecular mechanism of psoriasis, and we describe the functions and induction mechanisms of these biomarker candidates.

Janus kinase-signal transducers and activators of transcription cell signaling in Spondyloarthritis: rationale and evidence for JAK inhibition

PURPOSE OF REVIEW

The Janus kinase-signal transducers and activators of transcription (JAK-STAT) signaling proteins represent a group of intracellular kinase molecules that play a central role in the signaling pathways induced by cytokines, chemokines, and certain growth factors associated with systemic and local inflammation of autoimmune diseases including in Spondyloarthritis (SpA). Here, we will discuss (i) the functional significance of the JAK-STAT kinase cascades in the inflammatory-proliferative processes of SpA and its cellular/molecular mechanisms (ii) progress in the development of oral synthetic JAK inhibitors (JAKi) and their therapeutic efficacies in SpA.

RECENT FINDINGS

Development JAKi is a fast-moving field in the medical science. Several new-generation JAKi are being identified for psoriatic arthritis and ankylosing spondylitis. It is expected these JAKi likely to have higher potency and less adverse effects.

SUMMARY

Here, we are providing an updated review on the significance of JAK-STAT signaling proteins in SpA with an emphasis on new-generation of JAK-STAT inhibitors for the treatment of SpA.

Targeting JAK-STAT Signalling Alters PsA Synovial Fibroblast Pro-Inflammatory and Metabolic Function

Objectives

Psoriatic arthritis (PsA) is a chronic inflammatory disease associated with psoriasis. Janus Kinase inhibitors (JAKi) have emerged as an encouraging class of drugs for the treatment of PsA. Here, we compare the effect of four JAKi on primary PsA synovial fibroblasts (PsAFLS) activation, metabolic function, and invasive and migratory capacity.

Methods

Primary PsAFLS were isolated and cultured with JAKi (Peficitinib, Filgotinib, Baricitinib and Upadacitinib) in the presence of Oncostatin M (OSM). pSTAT3 expression in response to OSM was quantified by Western Blot analysis. Pro-inflammatory cytokines/chemokines were quantified by ELISA and cell migration by wound-repair scratch assays. Invasive capacity was examined using Matrigel™ invasion chambers and MMP multiplex MSD assays. PsAFLS bioenergetics was assessed using the Seahorse XF^e Extracellular Flux Analyzer, which simultaneously quantifies two energetic pathways- glycolysis (ECAR) and oxidative phosphorylation (OCR). In parallel, inflammatory, invasive, and migratory genes were quantified by RT-PCR.

Results

OSM induces pSTAT3 expression in PsAFLS. OSM-induced secretion of MCP-1 and IL-6 was inhibited by all JAKi with Peficitinib, Baricitinib and Upadacitinib showing the greatest effect. In contrast, JAKi had no significant impact on IL-8 expression in response to OSM. PsAFLS cell invasion, migratory capacity and MMP1, 3, and 9 were suppressed following JAKi treatment, with Peficitinib showing the greatest effect. These functional effects were accompanied by a change in the cellular bioenergetic profile of PsAFLS, where JAKi significantly decreased glycolysis and the ECAR/OCR, resulting in a shift to a more quiescent phenotype, with Peficitinib demonstrating the most pronounced effect.

Conclusion

This study demonstrates that JAK/STAT signalling mediates the complex interplay between inflammation and cellular metabolism in PsA pathogenesis. This inhibition shows effective suppression of inflammatory mechanisms that drive pathogenic functions of PsAFLS, further supporting the role of JAKi as a therapeutic target for the treatment of PsA.

Infliximab modifies regulatory T cells and co-inhibitory receptor expression on circulating T cells in psoriasis

BACKGROUND

Psoriasis is a T cell-mediated autoimmune skin disease. Accumulating evidence has demonstrated that co-inhibitory receptors (CIRs) play a vital role in regulating T cell-mediated immune response, especially in neoplasm and autoimmunity. However, the immuno-function of CIRs in the development of psoriasis remains unclear.

OBJECTIVE

We investigated the expression of CIRs on the circulating T lymphocytes of psoriasis patients before and after anti-tumor necrosis factor-α (TNF-α) therapy.

METHODS

We enrolled 17 patients with moderate-to-severe plaque psoriasis, 17 patients with mild plaque psoriasis, and 18 healthy controls in this study. Fourteen of the moderate-to-severe psoriasis patients were treated with infliximab, a monoclonal antibody against TNF-α. Peripheral blood was collected, and peripheral blood mononuclear cells were extracted. The proportion of T cell subsets along with their expression of CIRs, namely T cell immunoreceptor with Ig and ITIM domains (TIGIT), lymphocyte activating gene 3 (LAG-3), cytotoxic T-lymphocyte associated protein 4 (CTLA-4), B and T lymphocyte-associated protein (BTLA), endothelial protein C receptor (PROCR), podoplanin (PDPN), programmed cell death 1 (PD-1), and T cell immunoglobulin mucin family containing molecule 3 (TIM-3), were determined by flow cytometric assay.

RESULTS

The moderate-to-severe plaque psoriasis patients had less circulating Tregs, which increased after infliximab treatment. They also had decreased TIGIT, LAG-3 but increased PDPN expression on peripheral CD4⁺ T cells. Infliximab enhanced TIGIT, LAG-3, CTLA-4 but reduced PROCR expression on circulating CD4⁺ T cells. Remarkably, both the frequency of circulating Tregs and the expression level of TIGIT on CD4⁺ T cells at baseline (pre-treatment) negatively correlated with the extent of PASI score reduction benefited from infliximab therapy.

CONCLUSION

Anti-TNF-α therapy increased the frequency of Tregs and TIGIT, LAG-3, CTLA-4 expression but reduced PROCR expression on circulating CD4⁺ T cells in psoriasis patients. The baseline proportion of Tregs and the expression level of TIGIT on circulating CD4⁺ T cells might serve as predictive markers for the degree of disease remission benefited from infliximab treatment.

Podoplanin is required for tumor cell invasion in cutaneous squamous cell carcinoma

The invasiveness of late-stage cutaneous squamous cell carcinoma (cSCC) is associated with poor patients' prognosis and linked to strong upregulation of the glycoprotein Podoplanin (PDPN) in cancer cells. However, the function of PDPN in these processes in cSCC carcinogenesis has not been characterized in detail yet. Employing a CRISPR/Cas9-based loss-of-function approach on murine cSCC cells, we show that the loss of Pdpn results in decreased migration and invasion in vitro. Complementing these in vitro studies, labelled murine control and Pdpn knockout cells were injected orthotopically into the dermis of nude mice to recapitulate the formation of human cSCC displaying a well-differentiated morphology with a PDPN-positive reaction in fibroblasts in the tumor stroma. Smaller tumors were observed upon Pdpn loss, which is associated with reduced tumor cell infiltration into the stroma. Utilizing Pdpn mutants in functional experiments in vitro, we provide evidence that both the intra- and extracellular domains are essential for cancer cell invasion. These findings underline the critical role of PDPN in cSCC progression and highlight potential therapeutic strategies targeting PDPN-dependent cancer cell invasion, especially in late-stage cSCC patients.

The Detection of Plasma Soluble Podoplanin of Patients with Breast Cancer and Its Clinical Signification

Background

Podoplanin (PDPN) is a type-1 membrane sialoglycoprotein that is expressed in many cancer tumors including breast cancer; nonetheless, its roles in tumor occurrence, development, and metastasis are unclear. In this study, we aimed to investigate the clinical significance of plasma soluble PDPN (sPDPN) levels in patients with breast cancer and its significance in the diagnosis and metastasis.

Materials and Methods

Blood samples from healthy controls (CTL), patients with fibroadenomas of breast (FOB), and breast cancer (pathological type: invasive ductal carcinoma, IDC) were collected. sPDPN levels in the plasma of CTL and patients with FOB and IDC were measured by the ELISA.

Results

The plasma sPDPN levels in IDC patients (159 cases, 22.59±3.70 ng/mL) were higher than those in FOB patients (50 cases, 8.29±1.09 ng/mL; P<0.05) and CTL (100 cases, 1.21±0.12 ng/mL; P<0.0001). The sPDPN levels in patients at stage III and stage IV (30.08±4.66 ng/mL) were higher than in patients at stage I and stage II (11.84±1.12 ng/mL; P=0.005). The sPDPN levels in patients with high-moderate and moderate differentiation (17.50±3.02 ng/mL) were lower than those in patients with moderately low and low differentiation (35.73±4.26 ng/mL; P=0.026). The sPDPN levels in patients with metastasis (30.60±4.27 ng/mL) were much higher than those in patients without metastasis (13.02±1.30 ng/mL; P=0.017).

Conclusion

Plasma sPDPN may be used as a new marker for the determination of the clinical stage, differentiation degree, and metastasis status of breast cancer.

Interplay between Podoplanin, CD44s and CD44v in Squamous Carcinoma Cells

Podoplanin and CD44 are transmembrane glycoproteins involved in inflammation and cancer. In this paper, we report that podoplanin is coordinately expressed with the CD44 standard (CD44s) and variant (CD44v) isoforms in vivo—in hyperplastic skin after a pro-inflammatory stimulus with 12-O-tetradecanoylphorbol-13-acetate (TPA)—and in vitro—in cell lines representative of different stages of mouse-skin chemical carcinogenesis, as well as in human squamous carcinoma cell (SCC) lines. Moreover, we identify CD44v10 in the mouse-skin carcinogenesis model as the only CD44 variant isoform expressed in highly aggressive spindle carcinoma cell lines together with CD44s and podoplanin. We also characterized CD44v3-10, CD44v6-10 and CD44v8-10 as the major variant isoforms co-expressed with CD44s and podoplanin in human SCC cell lines. Immunofluorescence confocal microscopy experiments show that these CD44v isoforms colocalize with podoplanin at plasma membrane protrusions and cell–cell contacts of SCC cells, as previously reported for CD44s. Furthermore, CD44v isoforms colocalize with podoplanin in chemically induced mouse-skin SCCs in vivo. Co-immunoprecipitation experiments indicate that podoplanin physically binds to CD44v3-10, CD44v6-10 and CD44v8-10 isoforms, as well as to CD44s. Podoplanin–CD44 interaction is mediated by the transmembrane and cytosolic regions and is negatively modulated by glycosylation of the extracellular domain. These results point to a functional interplay of podoplanin with both CD44v and CD44s isoforms in SCCs and give insight into the regulation of the podoplanin–CD44 association.

Circulating tumor cell enumeration for improved screening and disease detection of patients with colorectal cancer

Background

The immunochemical fecal occult blood test (iFOBT) for colorectal cancer (CRC) screening and the serum carcinoembryonic antigen (CEA) assay for disease detection of CRC is associated with a high false-positive rate and a low detection sensitivity, respectively. There is an unmet need to define additional modalities to complement these assays. Different subsets of circulating tumor cells (CTCs) are present in the peripheral blood of cancer patients. Whether or not CTCs testing supplements these clinical assays and is valuable for patients with CRC was investigated.

Methods

CTCs were enriched from pre-operative patients with CRC (n = 109) and the non-cancerous controls (n = 65). CTCs expressing either epithelial cell adhesion molecule (EpCAM) or podoplanin (PDPN, the marker associated with poor cancer prognosis) were defined by immunofluorescence staining and were analyzed alone or in combination with iFOBT or serum CEA.

Results

Patients with early or advanced stage of CRC can be clearly identified and differentiated from the non-cancerous controls (p < 0.001) by EpCAM⁺-CTC or PDPN⁺-CTC count. The sensitivity and specificity of EpCAM⁺-CTCs was 85.3% and 78.5%, respectively, when the cutoff value was 23 EpCAM⁺-CTCs/mL of blood; and the sensitivity and specificity of PDPN⁺-CTCs was 78.0% and 75.4%, respectively, when the cutoff value was 7 PDPN⁺-CTCs/mL of blood. Combined analysis of iFOBT with the EpCAM⁺-CTC and PDPN⁺-CTC count reduced the false-positive rate of iFOBT from 56.3% to 18.8% and 23.4%, respectively. Combined analysis of serum CEA with the EpCAM⁺-CTC and PDPN⁺-CTC count increased the disease detection rate from 30.3% to 89.9% and 86.2%, respectively.

Conclusion

CTC testing could supplement iFOBT to improve CRC screening and supplement serum CEA assay for better disease detection of patients with CRC.

Omics-Driven Biomarkers of Psoriasis: Recent Insights, Current Challenges, and Future Prospects

Advances in omics technologies have made it possible to unravel biomarkers from different biological levels. Intensive studies have been carried out to uncover the dysregulations in psoriasis and to identify molecular signatures associated with the pathogenesis of psoriasis. In this review, we presented an overview of the current status of the omics-driven biomarker research and emphasized the transcriptomic, epigenomic, proteomic, metabolomic, and glycomic signatures proposed as psoriasis biomarkers. Furthermore, insights on the limitations and future directions of the current biomarker discovery strategies were discussed, which will continue to comprehend broader visions of psoriasis research, diagnosis, and therapy especially in the context of personalized medicine.

Keratinocyte-Expressed Podoplanin is Dispensable for Multi-Step Skin Carcinogenesis

Podoplanin is a small transmembrane mucin-like glycoprotein that plays a crucial role in the development of the lung, heart and lymphatic vascular system. Its expression is upregulated in several types of human carcinomas and podoplanin levels in squamous cell carcinomas (SCCs) of the oral cavity and the lung correlate with cancer invasiveness, lymph node metastasis and shorter survival time of patients, indicating that podoplanin promotes tumor progression. However, its role during the early stages of carcinogenesis remain unclear. We generated mice with a specific deletion of podoplanin in epidermal keratinocytes (K5-Cre;Pdpn^flox/flox mice) and subjected them to a multistep chemical skin carcinogenesis regimen. The rate of tumor initiation; the number, size and differentiation of tumors; and the malignant transformation rate were comparable in K5-Cre;Pdpn^flox/flox mice and Pdpn^flox/flox control mice. However, tumor cell invasion was reduced in K5-Cre;Pdpn^flox/flox mice, in particular single cell invasion. Quantitative immunofluorescence analyses revealed that peritumoral lymphangiogenesis was reduced in K5-Cre;Pdpn^flox/flox mice, whereas there were no major changes of tumor-associated immune cell subpopulations. Thus, keratinocyte-expressed podoplanin is dispensable for the early steps of skin carcinogenesis but contributes to the progression of established tumors.

Podoplanin expression is a prognostic biomarker but may be dispensable for the malignancy of glioblastoma

BACKGROUND

Treatment options of glioblastoma, the most aggressive primary brain tumor with frequent relapses and high mortality, are still very limited, urgently calling for novel therapeutic targets. Expression of the glycoprotein podoplanin correlates with poor prognosis in various cancer entities, including glioblastoma. Furthermore, podoplanin has been associated with tumor cell migration and proliferation in vitro; however, experimental data on its function in gliomagenesis in vivo are still missing. Hence, we have functionally investigated the impact of podoplanin on glioblastoma in a preclinical mouse model to evaluate its potential as a therapeutic target.

METHODS

Fluorescence activated cell sorting, genome-wide expression analysis, and clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated nuclease 9 (Cas9)-mediated deletion of podoplanin in patient-derived human glioblastoma cells were combined with organotypic brain slice cultures and intracranial injections into mice.

RESULTS

We defined a malignant gene signature in tumor cells with high podoplanin expression. The increase and/or maintenance of high podoplanin expression in serial transplantations and in podoplaninlow-sorted glioblastoma cells during outgrowth indicated the association of high podoplanin expression and poor outcome. Unexpectedly, similar rates of proliferation, apoptosis, angiogenesis, and invasion were observed in control and podoplanin-deleted tumors. Accordingly, neither tumor growth nor survival was affected upon podoplanin loss.

CONCLUSION

We report that tumor progression occurs independently of podoplanin. Thus, in contrast to previous suggestions, blocking of podoplanin does not represent a promising therapeutic approach. However, as podoplanin is associated with tumor aggressiveness and progression, we propose the cell surface protein as a biomarker for poor prognosis.

New Therapeutic Strategies for Osteoarthritis by Targeting Sialic Acid Receptors

Osteoarthritis (OA) is the most common degenerative joint disease characterized by articular cartilage degradation and joint degeneration. The articular cartilage is mainly formed by chondrocytes and a collagen-proteoglycan extracellular matrix that contains high levels of glycosylated proteins. It was reported that the shift from glycoproteins containing α-2,6-linked sialic acids to those that contain α-2,3 was associated with the onset of common types of arthritis. However, the pathophysiology of α-2,3-sialylation in cartilage has not been yet elucidated. We show that cartilage from osteoarthritic patients expresses high levels of the α-2,3-sialylated transmembrane mucin receptor, known as podoplanin (PDPN). Additionally, the Maackia amurensis seed lectin (MASL), that can be utilized to target PDPN, attenuates the inflammatory response mediated by NF-kB activation in primary chondrocytes and protects human cartilage breakdown ex vivo and in an animal model of arthritis. These findings reveal that specific lectins targeting α-2,3-sialylated receptors on chondrocytes might effectively inhibit cartilage breakdown. We also present a computational 3D molecular model for this interaction. These findings provide mechanistic information on how a specific lectin could be used as a novel therapy to treat degenerative joint diseases such as osteoarthritis.

Interleukin-17A and Keratinocytes in Psoriasis

The excellent clinical efficacy of anti-interleukin 17A (IL-17A) biologics on psoriasis indicates a crucial pathogenic role of IL-17A in this autoinflammatory skin disease. IL-17A accelerates the proliferation of epidermal keratinocytes. Keratinocytes produce a myriad of antimicrobial peptides and chemokines, such as CXCL1, CXCL2, CXCL8, and CCL20. Antimicrobial peptides enhance skin inflammation. IL-17A is capable of upregulating the production of these chemokines and antimicrobial peptides in keratinocytes. CXCL1, CXCL2, and CXCL8 recruit neutrophils and CCL20 chemoattracts IL-17A-producing CCR6⁺ immune cells, which further contributes to forming an IL-17A-rich milieu. This feed-forward pathogenic process results in characteristic histopathological features, such as epidermal hyperproliferation, intraepidermal neutrophilic microabscess, and dermal CCR6⁺ cell infiltration. In this review, we focus on IL-17A and keratinocyte interaction regarding psoriasis pathogenesis.

Podoplanin promotes cancer-associated thrombosis and contributes to the unfavorable overall survival in an ectopic xenograft mouse model of oral cancer

Background

Podoplanin (PDPN) is a transmembrane glycoprotein that mediates tumor cell-induced platelets aggregation in different cancer types. Emerging data indicate that PDPN is a marker for poor prognosis of human oral squamous cell carcinoma (OSCC). However, the functional impacts of PDPN on cancer formation and disease progression of OSCC remain to be elucidated.

Methods

The sublines of the OECM-1 oral cancer cells with PDPN knockdown or overexpression were established. The cellular characteristics and the ability to induce platelet aggregation of these cells lines were analyzed. An ectopic xenograft animal model by inoculating cancer cells into the anterior neck region of nude mice was established to investigate the functional impact of PDPN on disease progression and cancer-associated thrombosis of OSCC.

Results

PDPN promoted OSCC cell migration and invasion, but had no effect on cell proliferation in vitro and tumor growth in vivo. Co-incubation of PDPN-positive (PDPN⁺) OSCC cells with platelets induced platelet activation and aggregation. The mice bearing PDPN⁺ tumor had a decrease in overall survival despite that there was no gross appearance of distant metastasis. A speckled immunofluorescence staining pattern of platelet marker mCD41 was defined in the PDPN⁺ tumor sections and the intensity was greater than in the PDPN-low or negative tumor sections. Co-immunofluorescence staining of the tumor sections with mCD41 and the endothelial cell marker mCD31 further demonstrated that platelet aggregates were located in the lumen of blood vessel and were also distributed intratumorally in the mice bearing PDPN⁺ tumors.

Conclusions

These data demonstrated that PDPN expression in the cancer cells is associated with high risk of thrombosis, leading to unfavorable overall survival of the mice. This study provides new insights into the functions of PDPN in cancer-associated thrombosis and in the pathophysiology of OSCC.

TRIM27 promotes IL-6-induced proliferation and inflammation factor production by activating STAT3 signaling in HaCaT cells

The IL-6/STAT3 signaling pathway is required for the development of psoriatic lesions, and tripartite motif-containing 27 (TRIM27) is a protein inhibitor of activated STAT3 (PIAS3)-interacting protein that could modulate IL-6-induced STAT3 activation. However, whether TRIM27 is associated with the IL-6/STAT3 signaling pathway in psoriasis remains enigmatic. TRIM27 expression and gene set enrichment analysis in patients with psoriasis were determined using bioinformatics. Human keratinocyte HaCaT cells treated with recombinant protein IL-6 (rh-IL-6) were transduced with lentivirus silencing TRIM27 and/or PIAS3 or, otherwise, transduced with lentivirus expressing TRIM27 and/or lentivirus silencing STAT3, or MG132, a proteasome-specific protease inhibitor. Cell proliferation and inflammation factor production were measured using Cell Counting Kit-8 and ELISA, respectively. TRIM27, proliferation marker protein Ki-67 (Ki67), phospho-STAT3 (p-STAT3), STAT3, and PIAS3 expressions were determined using real-time quantitative PCR, immunofluorescence staining, or Western blot analysis. Coimmunoprecipitation combined with ubiquitination analysis was performed to explore the interaction between TRIM27 and PIAS3. In the present study, TRIM27 expression was increased in psoriatic lesions, associated with the IL-6 signaling pathway, and induced by rh-IL-6 in a time-dependent manner. The increased cell proliferation, inflammation factor production, and expression of Ki67 and of p-STAT3 relative to STAT3 induced by rh-IL-6 and TRIM27 overexpression were significantly inhibited by TRIM27 silencing and STAT3 silencing, respectively. More importantly, TRIM27 interacted with PIAS3, and its overexpression promoted PIAS3 ubiquitination in HaCaT cells. PIAS3 silencing also significantly promoted TRIM27-dependent and IL6-induced STAT3 activation, cell proliferation, and inflammation factor production. In conclusion, our results highlight that TRIM27 expression is significantly increased by IL-6 and suggest a TRIM27/STAT3-dependent mechanism for regulation of inflammation and proliferation-associated development of psoriasis.

An important role of podoplanin in hair follicle growth

Podoplanin (PDPN) is a glycoprotein that is expressed by various cell types, including keratinocytes, fibroblasts, and lymphatic endothelial cells. We found that PDPN is expressed in the hair follicle (HF) keratinocyte region and HF stem cell area during the late anagen phase but not during the telogen phase in mice. Importantly, keratinocyte-specific PDPN deletion in mice (K5-Cre;PDPN^flox/flox) promoted anagen HF growth after depilation-induced HF regeneration as compared to control mice. RNA sequencing, followed by gene ontology analysis, showed down-regulation of focal adhesion and extracellular matrix interaction pathways in HF stem cells isolated from K5-Cre;PDPN^flox/flox mice as compared to control mice. Furthermore, HF keratinocytes isolated from K5-Cre;PDPN^flox/flox mice exhibited a decreased ability to interact with collagen type I in cell adhesion assays. Taken together, these results show that PDPN deletion promotes HF cycling, possibly via reduced focal adhesion and concomitantly enhanced migration of HF stem cells towards the bulb region. They also indicate potential new therapeutic strategies for the treatment of conditions associated with hair loss.

Podoplanin in Inflammation and Cancer

Podoplanin is a small cell-surface mucin-like glycoprotein that plays a crucial role in the development of the alveoli, heart, and lymphatic vascular system. Emerging evidence indicates that it is also involved in the control of mammary stem-cell activity and biogenesis of platelets in the bone marrow, and exerts an important function in the immune response. Podoplanin expression is upregulated in different cell types, including fibroblasts, macrophages, T helper cells, and epithelial cells, during inflammation and cancer, where it plays important roles. Podoplanin is implicated in chronic inflammatory diseases, such as psoriasis, multiple sclerosis, and rheumatoid arthritis, promotes inflammation-driven and cancer-associated thrombosis, and stimulates cancer cell invasion and metastasis through a variety of strategies. To accomplish its biological functions, podoplanin must interact with other proteins located in the same cell or in neighbor cells. The binding of podoplanin to its ligands leads to modulation of signaling pathways that regulate proliferation, contractility, migration, epithelial⁻mesenchymal transition, and remodeling of the extracellular matrix. In this review, we describe the diverse roles of podoplanin in inflammation and cancer, depict the protein ligands of podoplanin identified so far, and discuss the mechanistic basis for the involvement of podoplanin in all these processes.

Podoplanin suppresses the cell adhesion of epidermal keratinocytes via functional regulation of β1-integrin

Epidermal stem cells adhere more efficiently to the extracellular matrix (ECM) than the less adhesive differentiating cells due to their high expression of cell adhesion molecules including β1-integrin. Podoplanin is majorly expressed in the markedly proliferative and differentiating basal cells of the wounded and psoriatic epidermis. This study was designed to reveal podoplanin's function in human epidermal keratinocytes (HEK) focusing on its interaction with β1-integrin. We analyzed the adhesion and differentiation of HEK in both podoplanin-overexpressing and -knock-down cells, considering their β1-integrin levels. The basal layer of IL-22-treated hyperproliferative reconstituted epidermis cells (simulating basal hyperproliferative psoriatic epidermal basal cells) expressed higher podoplanin levels than the untreated control cells. The adhesiveness of HaCaT cells, which do not express podoplanin, was reduced after the overexpression of podoplanin. HEK with podoplanin overexpression suppressed the cell adhesion to type I collagen (while downregulating β1-integrin functions) and podoplanin silencing augmented it (by increasing active ECM-bound β1-integrin). The increased cell adhesion to type I collagen induced by podoplanin silencing could be reversed by addition of P5D2, a neutralizing antibody against β1-integrin. In the psoriatic epidermis, podoplanin expression was especially upregulated on the rete ridges of the basal cell layer. This expression pattern was inversely correlated with the total/ECM-bound active β1-integrin-expression, which was stronger at the basal cell layer covering the dermal papillae. Our results indicate that podoplanin inhibits the cell ECM attachment by suppressing β1-integrin and initiating HEK differentiation. Podoplanin is presumably involved in the pathogenesis of psoriasis.

Anti-IL-22 Antibody Attenuates Acute Graft-versus-Host Disease via Increasing Foxp3+ T Cell through Modulation of CD11b+ Cell Function

Transfer of splenocytes isolated from B6 mice into normal B6D2F1 mice induces acute graft-versus-host disease (aGVHD), resulting in the expansion of donor cytotoxic T lymphocytes that eliminate recipient B cells. The cytokine IL-22, secreted by Th1 cells, Th17 cells, and innate immune cells, is structurally related to IL-10. To investigate the association between IL-22 and aGVHD, an anti-mouse IL-22 antibody (IL-22Ab) was used to ablate IL-22 activity in a mouse aGVHD model. Administration of IL-22Ab significantly reduced the progression of aGVHD in B6D2F1 recipients of B6 grafts. IL-22Ab treatment also decreased the percentage of interferon-γ+ and tumor necrosis factor-α+ T cells but increased the number of forkhead box p3+ regulatory T cells (Tregs). In the presence of Tregs and donor CD11b+ cells, IL-22Ab protected against aGVHD. In vitro Treg induction was more efficient when CD4+CD25- T cells differentiated in the presence of CD11b+ cells obtained from IL-22Ab-treated GVHD mice, compared with cocultured untreated control cells. Finally, IL-22Ab modulated the expression of cytokines and costimulatory molecules in CD11b+ cells in aGVHD mice. We therefore conclude that IL-22Ab administration represents a viable approach for treating aGVHD.

Is podoplanin expression associated with transforming growth factor-β signaling in odontogenic cysts and tumors?

BACKGROUND

Induction of podoplanin by transforming growth factor-β (TGF-β) has been shown in a number of lesions but not in odontogenic tumors (OTs). We evaluated the association between these markers in OTs for the first time and compared their expression among the different neoplasms.

METHODS

Immunohistochemistry using monoclonal antibody against podoplanin and TGF-β was performed on 76 odontogenic cysts and tumors. Spearman's correlation coefficient, Kruskal-Wallis, and Mann-Whitney U tests followed by adjustment with Bonferroni were used for statistical analysis (P < .05).

RESULTS

A significant difference in podoplanin expression was found among the lesions consisting of solid ameloblastomas, adenomatoid odontogenic tumors, ameloblastic fibromas, odontogenic myxomas (OMs), odontogenic keratocysts, and calcifying odontogenic cysts. Significant differences were observed only between OMs and each of the other neoplasms. Podoplanin immunostaining in the connective tissue was absent in most lesions. TGF-β was significantly different among the study sample but not between the lesions in paired comparisons. None of the studied OTs showed significant correlations between podoplanin-TGF-β, in either the epithelium or the stroma. These markers were also descriptively reported in calcifying epithelial odontogenic tumors.

CONCLUSIONS

The inductive effect of TGF-β on podoplanin seems to be limited, if any, in odontogenic lesions. Podoplanin appears to play a role in some aspects of OTs with epithelial or mixed origins. Despite the possible participation of podoplanin in tumorigenesis, it may not necessarily be involved in the aggressive behavior of OTs.

Inflammatory Cytokines Induce Podoplanin Expression at the Tumor Invasive Front

Tumor invasion is a critical first step in the organismic dissemination of cancer cells and the formation of metastasis in distant organs, the most important prognostic factor and the actual cause of death in most of the cancer patients. We report herein that the cell surface protein podoplanin (PDPN), a potent inducer of cancer cell invasion, is conspicuously expressed by the invasive front of squamous cell carcinomas (SCCs) of the cervix in patients and in the transgenic human papillomavirus/estrogen mouse model of cervical cancer. Laser capture microscopy combined with gene expression profiling reveals that the expression of interferon-responsive genes is up-regulated in PDPN-expressing cells at the tumor invasive front, which are exposed to CD45-positive inflammatory cells. Indeed, PDPN expression can be induced in cultured SCC cell lines by single or combined treatments with interferon-γ, transforming growth factor-β, and/or tumor necrosis factor-α. Notably, shRNA-mediated ablation of either PDPN or STAT1 in A431 SCC cells repressed cancer cell invasion on s.c. transplantation into immunodeficient mice. The results highlight the induction of tumor cell invasion by the inflammatory cytokine-stimulated expression of PDPN in the outermost cell layers of cervical SCC.

Janus kinase/signal transducer and activator of transcription pathways in spondyloarthritis

PURPOSE OF REVIEW

Cytokines are major drivers of autoimmunity, and biologic agents targeting cytokines have revolutionized the treatment of immune-mediated diseases. Janus kinase/signal transducer and activator of transcription (JAK-STAT) pathway represents a group of several intracellular molecules with a key role in signal pathways activated by growth factors and cytokines. These kinase proteins are associated with the signaling process of multiple key cytokines, which regulates various T-cell subpopulations and their effector cytokines. Development of novel drugs to inhibit this kinase cascade is an emerging field in clinical immunology. Thus, it is essential to have insights about the regulatory role of the JAK-STAT cytokine signaling in relation to autoimmune diseases and its applications in spondyloarthritis.

RECENT FINDINGS

JAK-STAT kinase signaling proteins have been extensively studied in rheumatoid arthritis. Initial observations suggest that JAK-STAT kinase signaling cascade regulates activation and proliferation of the IL17 effector memory T cells and thus has a potential role in the pathogenesis of psoriasis, psoriatic arthritis and ankylosing spondylitis.

SUMMARY

Here, we provide an overview of the clinical rheumatologists about the significance of JAK-STAT signaling system in rheumatic diseases and introduce the potential application of JAK and STAT inhibitors in spondyloarthritis.

Upregulation of BAG3 with apoptotic and autophagic activities in maggot extract‑promoted rat skin wound healing

Maggot extract (ME) accelerates rat skin wound healing, however its effect on cell maintenance in wound tissues remains unclear. B‑cell lymphoma (Bcl) 2‑associated athanogene (BAG)3 inhibits apoptosis and promotes autophagy by associating with Bcl‑2 or Beclin 1. Bcl‑2, the downstream effector of signal transducer and activator of transcription 3 signaling, is enhanced in ME‑treated wound tissues, which may reinforce the Bcl‑2 anti‑apoptotic activity and/or cooperate with Beclin 1 to regulate autophagy during wound healing. The present study investigated expression levels of BAG3, Bcl‑2, Beclin 1 and light chain (LC)3 levels in rat skin wound tissues in the presence and absence of ME treatment. The results revealed frequent TUNEL‑negative cell death in the wound tissues in the early three days following injury, irrespective to ME treatment. TUNEL‑positive cells appeared in the wound tissues following 4 days of injury and 150 µg/ml ME efficiently reduced apoptotic rate and enhanced BAG3 and Bcl‑2 expression. Elevated Beclin 1 and LC3 levels and an increased LC3 II ratio were revealed in the ME‑treated tissues during the wound healing. The results of the present study demonstrate the anti‑apoptotic effects of BAG3 and Bcl‑2 in ME‑promoted wound healing. Beclin 1/LC3 mediated autophagy may be favorable in maintaining cell survival in the damaged tissues and ME‑upregulated BAG3 may enhance its activity.

Podoplanin is a negative regulator of Th17 inflammation

Recent data indicate that there are different subpopulations of Th17 cells that can express a regulatory as opposed to an inflammatory gene signature. The transmembrane glycoprotein PDPN is critical in the development of multiple organs including the lymphatic system and has been described on T cells in mouse models of autoimmune Th17 inflammation. Here, we demonstrate that unlike in mice, PDPN+ T cells induced under classic Th17-polarizing conditions express transcription factors associated with Th17 cells but do not produce IL-17. Moreover, these cells express a transcriptional profile enriched for immunosuppressive and regulatory pathways and express a distinct cytokine profile compared with potentially pathogenic PDPN- Th17 cells. Ligation of PDPN by its ligand CLEC-2 ameliorates the Th17 inflammatory response. IL-17 secretion is restored with shRNA gene silencing of PDPN. Furthermore, PDPN expression is reduced via an Sgk1-mediated pathway under proinflammatory, high sodium chloride conditions. Finally, CD3+PDPN+ T cells are devoid of IL-17 in skin biopsies from patients with candidiasis, a prototypical Th17-driven skin disease. Thus, our data support the hypothesis that PDPN may serve as a marker of a nonpathogenic Th17 cell subset and may also functionally regulate pathogenic Th17 inflammation.

Effects of RNA interference combined with ultrasonic irradiation and SonoVue microbubbles on expression of STAT3 gene in keratinocytes of psoriatic lesions

The most effective sequence of small interfering RNA (siRNA) silencing STAT3 of psoriatic keratinocytes (KCs) was screened out, and the effects of the most effective siRNA combined with ultrasonic irradiation and SonoVue microbubbles on the expression of STAT3 of KCs and the dose- and time-response were investigated. Three chemically-synthetic siRNAs targeting STAT3 carried by Lipofectamine 3000 were transfected into KCs, and the effects on STAT3 expression were detected, then the most effective siRNA was selected for the subsequent experiments. The negative controls of siRNA (siRNA-NC) labeled with Cy3 carried by Lipofectamine 3000 combined with ultrasonic irradiation and SonoVue microbubbles were transfected into KCs, then the optimal parameters of ultrasonic irradiation were determined. The most effective siRNA carried by Li-pofectamine 3000 combined with ultrasonic irradiation at the optimal parameters and SonoVue microbubbles was transfected into KCs, and the dose- and time-response of RNA interference was determined. The effect of RNA interference by the most effective siRNA at the optimal time and dose carried by Lipofectamine 3000 combined with ultrasonic irradiation and SonoVue microbubbles (LUS group) was compared with that only carried by Li-pofectamine 3000 (L group). The results showed that siRNA-3 achieved the highest silencing efficacy. 0.5 W/cm2 and 30 s were selected as the parameters of ultrasonic irradiation. The siRNA-3 carried by Lipofectamine 3000 combined with ultrasonic irradiation and SonoVue microbubbles could effectively knock down the STAT3 expression at mRNA and protein levels in dose- and time-dependent manners determined at 100 nmol/L with maximum downregulation on mRNA at 48 h, and on protein at 72 h after transfection. The LUS group achieved the highest silencing efficacy. It was concluded that siRNA-3 carried by Lipofectamine 3000 combined with ultrasonic irradiation and SonoVue microbubbles could effectively knock down the STAT3 expression in psoriatic KCs, and the optimized transfection condition and the sequence of siRNA-3 could serve for further research on gene therapy of psoriasis.

Podoplanin expression in peritumoral keratinocytes predicts aggressive behavior in extramammary Paget's disease

BACKGROUND

Recent studies have demonstrated podoplanin expression in several tumors, which has been associated with lymph node metastasis and poor prognosis. Podoplanin expression in peritumoral cells such as cancer-associated fibroblasts also correlates with tumor progression in several cancers. However, podoplanin expression and its association with extramammary Paget's disease (EMPD) remain unclear.

OBJECTIVE

In this study, we examined whether the presence of podoplanin expression in tumor cells or peritumoral basal keratinocytes correlated with aggressive behavior in patients with EMPD and investigated the mechanisms of podoplanin-mediated tumor invasion in this disorder.

METHODS

Skin samples of 37 patients with EMPD were investigated by immunohistochemical analysis. The functions of podoplanin in keratinocytes were examined in vitro by RT-PCR and with invadopodia gelatin-degradation assays using HaCaT cells.

RESULTS

Podoplanin was not identified in tumor cells in all cases. Podoplanin expression in peritumoral basal keratinocytes was observed in 25 patients (67.6%). In in situ EMPD, 50% of cases (9 in 18) exhibited podoplanin-positive keratinocytes, whereas 84.2% (16 in 19) demonstrated positive staining in invasive EMPD (P<0.05). Podoplanin expression in peritumoral keratinocytes was also associated with tumor thickness (P<0.005). By immunohistochemical analysis, podoplanin-positive peritumoral keratinocytes were found to be negative for E-cadherin, one of the major adhesion molecules of keratinocytes, which might contribute to tumor invasion into the dermis through a crack in the basal cell layer induced by down-regulation of cell adhesion therein. We further found that podoplanin-positive keratinocytes exhibited invadopodia, which are thought to function in the migration of cancer cells through tissue barriers, indicating that podoplanin-positive peritumoral basal keratinocytes might assist tumor invasion by degrading the extracellular matrix.

CONCLUSION

The presence of podoplanin expression in peritumoral keratinocytes correlates with aggressive behavior in EMPD and might therefore serve as a useful prognostic marker for patients with EMPD.

Human Lymph Node-Derived Fibroblastic and Double-Negative Reticular Cells Alter Their Chemokines and Cytokines Expression Profile Following Inflammatory Stimuli

Lymph node (LN) is a secondary lymphoid organ with highly organized and compartmentalized structure. LNs harbor B, T, and other cells among fibroblastic reticular cells (FRCs). FRCs are characterized by both podoplanin (PDPN/gp38) expression and by the lack of CD31 expression. FRCs are involved in several immune response processes but mechanisms underlying their function are still under investigation. Double-negative cells (DNCs), another cell population within LNs, are even less understood. They do not express PDPN or CD31, their localization within the LN is unknown, and their phenotype and function remain to be elucidated. This study evaluates the gene expression and cytokines and chemokines profile of human LN-derived FRCs and DNCs during homeostasis and following inflammatory stimuli. Cytokines and chemokines secreted by human FRCs and DNCs partially diverged from those identified in murine models that used similar stimulation. Cytokine and chemokine secretion and their receptors expression levels differed between stimulated DNCs and FRCs, with FRCs expressing a broader range of chemokines. Additionally, dendritic cells demonstrated increased migration toward FRCs, possibly due to chemokine-induced chemotaxis since migration was significantly decreased upon neutralization of secreted CCL2 and CCL20. Our study contributes to the understanding of the biology and functions of FRCs and DNCs and, accordingly, of the mechanisms involving them in immune cells activation and migration.

Altered Dermal Fibroblasts in Systemic Sclerosis Display Podoplanin and CD90

Tissue injury triggers the activation and differentiation of multiple cell types to minimize damage and initiate repair processes. In systemic sclerosis, these repair processes appear to run unchecked, leading to aberrant remodeling and fibrosis of the skin and multiple internal organs, yet the fundamental pathological defect remains unknown. We describe herein a transition wherein the abundant CD34(+) dermal fibroblasts present in healthy human skin disappear in the skin of systemic sclerosis patients, and CD34(-), podoplanin(+), and CD90(+) fibroblasts appear. This transition is limited to the upper dermis in several inflammatory skin diseases, yet in systemic sclerosis, it can occur in all regions of the dermis. In vitro, primary dermal fibroblasts readily express podoplanin in response to the inflammatory stimuli tumor necrosis factor and IL-1β. Furthermore, we show that on acute skin injury in both human and murine settings, this transition occurs quickly, consistent with a response to inflammatory signaling. Transitioned fibroblasts partially resemble the cells that form the reticular networks in organized lymphoid tissues, potentially linking two areas of fibroblast research. These results allow for the visualization and quantification of a basic stage of fibroblast differentiation in inflammatory and fibrotic diseases in the skin.

Role of podoplanin in the high interleukin-17A secretion resulting from interactions between activated lymphocytes and psoriatic skin-derived mesenchymal cells

In the context of psoriasis, T helper type 17 (Th17) cells infiltrate the inflammatory site and interact with local mesenchymal cells, including skin fibroblasts. The aim of this work was to study the interactions of skin-derived fibroblasts with peripheral blood mononuclear cells (PBMC) with a focus on the Th17 pathway and to identify a mechanism which leads to a high interleukin (IL)-17 secretion. A co-culture system between PBMC and skin fibroblasts was developed. Healthy and patient PBMC were added to non-lesional or lesional skin fibroblasts at a 5:1 ratio for 48 h in the presence or not of activation with phytohaemagglutinin (PHA). Monocytes were removed or not by adherence before the co-culture. An anti-podoplanin antibody was also used during the co-culture. Cytokine production (IL-8, IL-6, IL-1β and IL-17) was measured by enzyme-linked immunosorbent assay (ELISA) and cell staining (CD3, CD4, IL-17 and podoplanin) by flow cytometry. Without T cell receptor (TCR) activation, IL-8, IL-6 and IL-1β production increased in PBMC-fibroblast co-culture compared to PBMC alone. No additional effect was observed with TCR activation, with no difference in the Th17 cell percentage in activated-PBMC alone or co-cultured. Conversely, IL-17 production was increased highly only in co-cultures between control and patient activated-PBMC and skin fibroblasts. Removal of monocytes decreased cytokine production, notably that of IL-17. Addition of an anti-podoplanin antibody decreased IL-17 secretion by 60%. Interactions between resting PBMC and fibroblasts induce the IL-8, IL-6 and IL-1β production. PBMC activation and cell interactions are critical for a high IL-17 secretion. Podoplanin contributes largely to this massive IL-17 secretion.

Podoplanin-mediated TGF-β-induced epithelial-mesenchymal transition and its correlation with bHLH transcription factor DEC in TE-11 cells

Podoplanin is reported involved in the collective cell invasion, another tumor invasion style which is distinct from the single cell invasion, so-called epithelial-mesenchymal transition (EMT). In this study, we investigated the correlation between podoplanin and EMT-related markers in esophageal squamous cell carcinoma (ESCC), and evaluated its linkage with the basic helix-loop-helix (bHLH) transcription factor differentiated embryonic chondrocyte (DEC) 1 and DEC2. Three ESCC cell lines and human squamous cell carcinoma A431 cells were subjected to western blot analyses for podoplanin and EMT markers, as well as the expression of DEC1 and DEC2. By RT-qPCR and western blotting, we found that TGF-β increased the expression of podoplanin and mensenchymal markers (e.g., N-cadherin and vimentin), while decreased the expression of epithelial markers (e.g., Claudin-4 and E-cadherin), accompanied by Smad2 phosphorylation and slug activation. Moreover, TGF-β has different effects on the expression of DEC1 and DEC2, that is, it upregulates DEC1, but downregulates DEC2. Capability of cell proliferation, invasion and migration were further analyzed using CCK-8 assay, Matrigel-invasion assay, and the wound-healing assay, respectively. The proliferation, invasion and migration ability were significantly lost in podoplanin-knockdown cells when compared with the scrambled siRNA group. In addition to these changes, the expression of Claudin-4, but not that of Claudin-1 or E-cadherin, was induced by the siRNA against podoplanin. On the contrary, overexpression of DEC1 and DEC2 exhibits opposite effects on podoplanin, but only slight effect on Claudin-4 was detected. These data indicated that podoplanin is significantly associated with EMT of TE-11 cells, and may be directly or indirectly regulated by bHLH transcription factors DEC1 and DEC2.

Inhibition of imiquimod-induced psoriasis-like dermatitis in mice by herbal extracts from some Indian medicinal plants

Psoriasis is a chronic autoimmune human skin disorder that is characterized by excessive proliferation of keratinocytes, scaly plaques, severe inflammation and erythema. The pathophysiology of psoriasis involves interplay between epidermal keratinocytes, T lymphocytes, leukocytes and vascular endothelium. Increased leukocyte recruitment and elevated levels of cytokines, growth factors and genetic factors like interleukin (IL)-1β, IL-6, IL-17, IL-22, IL-23, tumour necrosis factor (TNF)-α, interferon (IFN)-γ, transforming growth factor (TGF)-β, toll-like receptor (TLR)-2, signal transducer and activator of transcription (STAT-3), 15-lipoxygenase (LOX)-2, coiled-coil alpha-helical rod protein 1 (CCHCR1), steroidogenic acute regulatory protein (StAR) and vitamin D receptor (VDR) are the most critical factors governing the exacerbation of psoriasis. In the present study, an attempt was made to elucidate the preventive role of herbal extracts of four dermo-protective Ayurvedic plants, Tinospora cordifolia (TC), Curcuma longa (CL), Celastrus paniculatus (CP) and Aloe vera (AV), against psoriasis-like dermatitis. Parkes (P) strain mice were initially induced with psoriasis-like dermatitis using topical application of imiquimod (IMQ, 5 %), followed by subsequent treatment with the herbal extracts to examine their curative effect on the psoriasis-like dermatitis-induced mice. The extracts were orally/topically administered to mice according to their ED/LD50 doses. Phenotypical observations, histological examinations, and semi-quantitative reverse transcription PCR (RT-PCR) analyses of the skin and blood samples of the control, IMQ-treated and herbal extract-treated psoriasis-like dermatitis-induced mice lead to the conclusion that the combination extract from all the plants was instrumental in downregulating the overexpressed cytokines, which was followed by the CL extract. Moreover, lesser yet positive response was evident from CP and TC extracts. The results suggest that these plants can prove to have tremendous preventive potential against the disease and can open the way to new therapeutic strategies for psoriasis treatment.

A Case Report of Majocchi's Granuloma Associated with Combined Therapy of Topical Steroids and Adalimumab

Currently, tumor necrosis factor alpha (TNF-alpha) inhibitors are widely used for many autoimmune disorders. However, they cause an immunocompromised status that sometimes leads to many cutaneous side effects including atypical infections. Herein, we report the first case of adalimumab-related Majocchi's granuloma.A 43-year-old Taiwanese male patient with chronic plaque-type psoriasis developed numerous tender nodules 1 month after adalimumab injection. The nodules responded poorly to bacterial folliculitis treatment. After repeated skin biopsies for pathology and tissue fungal culture, Majocchi's granuloma was confirmed. Adalimumab was withheld, and 12 weeks of terbinafine treatment was given. On completion of treatment, the nodular skin lesions and dystrophic nail lesions improved dramatically.The information, including time span, clinical features, histological findings, and improvement following withdrawal of adalimumab and treatment with an oral antifungal agent, indicates that Majocchi's granuloma was adalimumab-related. Psoriasis patients are more susceptible to dermatophyte infection due to local and systemic immunosuppressant therapy. It is important to perform a thorough examination for latent dermatophyte infection, including skin and nail lesions, before treatment with TNF-alpha inhibitors and during traditional psoriasis treatment. When atypical presentation together with treatment failure is noted in psoriasis patients prescribed biologics, clinicians should investigate evidence of dermatophyte infection and provide proper treatment. Sometimes, multiple skin biopsies and tissue fungal cultures are required to establish a correct diagnosis.