IL-17D-induced inhibition of DDX5 expression in keratinocytes amplifies IL-36R-mediated skin inflammation.

Aberrant RNA splicing in keratinocytes drives inflammatory skin disorders. In the present study, we found that the RNA helicase DDX5 was downregulated in keratinocytes from the inflammatory skin lesions in patients with atopic dermatitis and psoriasis, and that mice with keratinocyte-specific deletion of Ddx5 (Ddx5∆KC) were more susceptible to cutaneous inflammation. Inhibition of DDX5 expression in keratinocytes was induced by the cytokine interleukin (IL)-17D through activation of the CD93-p38 MAPK-AKT-SMAD2/3 signaling pathway and led to pre-messenger RNA splicing events that favored the production of membrane-bound, intact IL-36 receptor (IL-36R) at the expense of soluble IL-36R (sIL-36R) and to the selective amplification of IL-36R-mediated inflammatory responses and cutaneous inflammation. Restoration of sIL-36R in Ddx5∆KC mice with experimental atopic dermatitis or psoriasis suppressed skin inflammation and alleviated the disease phenotypes. These findings indicate that IL-17D modulation of DDX5 expression controls inflammation in keratinocytes during inflammatory skin diseases.

Excessive Polyamine Generation in Keratinocytes Promotes Self-RNA Sensing by Dendritic Cells in Psoriasis.

Psoriasis is a chronic inflammatory disease whose etiology is multifactorial. The contributions of cellular metabolism to psoriasis are unclear. Here, we report that interleukin-17 (IL-17) downregulated Protein Phosphatase 6 (PP6) in psoriatic keratinocytes, causing phosphorylation and activation of the transcription factor C/EBP-ß and subsequent generation of arginase-1. Mice lacking Pp6 in keratinocytes were predisposed to psoriasis-like skin inflammation. Accumulation of arginase-1 in Pp6-deficient keratinocytes drove polyamine production from the urea cycle. Polyamines protected self-RNA released by psoriatic keratinocytes from degradation and facilitated the endocytosis of self-RNA by myeloid dendritic cells to promote toll-like receptor-7 (TLR7)-dependent RNA sensing and IL-6 production. An arginase inhibitor improved skin inflammation in murine and non-human primate models of psoriasis. Our findings suggest that urea cycle hyperreactivity and excessive polyamine generation in psoriatic keratinocytes promote self-RNA sensation and PP6 deregulation in keratinocytes is a pivotal event that amplifies the inflammatory circuits in psoriasis.

An Interleukin-25-Mediated Autoregulatory Circuit in Keratinocytes Plays a Pivotal Role in Psoriatic Skin Inflammation.

Psoriasis is a chronic autoinflammatory skin disease. Although interleukin-17, derived from lymphocytes, has been shown to be critical in psoriasis, the initiation and maintenance of chronic skin inflammation has not been well understood. IL-25 (also called IL-17E), another IL-17 family cytokine, is well known to regulate allergic responses and type 2 immunity. Here we have shown that IL-25, also highly expressed in the lesional skin of psoriasis patients, was regulated by IL-17 in murine skin of a imiquimod (IMQ)-induced psoriasis model. IL-25 injection induced skin inflammation, whereas germline or keratinocyte-specific deletion of IL-25 caused resistance to IMQ-induced psoriasis. Via IL-17RB expression in keratinocytes, IL-25 stimulated the proliferation of keratinocytes and induced the production of inflammatory cytokines and chemokines, via activation of the STAT3 transcription factor. Thus, our data demonstrate that an IL-17-induced autoregulatory circuit in keratinocytes is mediated by IL-25 and suggest that this circuit could be targeted in the treatment of psoriasis patients.

Better efficacy, lower recurrence rate and decreased CD8+TRM with guselkumab treatment for generalized pustular psoriasis: A prospective cohort study from China.

Generalized pustular psoriasis (GPP) is a severe and uncommon form of psoriasis, for which treatment options are limited. There is an urgent need to expand the treatment options for GPP. Currently, adalimumab, secukinumab, and guselkumab are considered effective for GPP, but there is a lack of prospective direct comparative studies on their efficacy for GPP. We conducted a prospective, single-center, observational study on 50 GPP patients to compare the efficacy, safety, and recurrence rates of these three biologics. Adalimumab, secukinumab, and guselkumab resulted in varying degrees of improvement in patients with GPP, but guselkumab exhibited superior efficacy and a lower recurrence rate than the other two drugs. This enhanced response may be attributed to the significant reduction in CD8+ tissue-resident memory T cells within GPP lesions caused by guselkumab.

A novel online calculator based on clinical features and hematological parameters to predict total skin clearance in patients with moderate to severe psoriasis.

BACKGROUND: Treatment responses to biologic agents vary between patients with moderate to severe psoriasis; while some patients achieve total skin clearance (TSC), a proportion of patients may only experience partial improvement. OBJECTIVE: This study was designed to identify potential predictors for achieving TSC in psoriasis patients treated with IL-17 inhibitors. It also aimed to develop an easy-to-use calculator incorporating these factors by the nomogram to predict TSC response. METHODS: A total of 381 patients with psoriasis receiving ixekizumab were included in the development cohort and 229 psoriasis patients who initiated secukinumab treatment were included in the validation cohort. The study endpoint was achieving TSC after 12 weeks of IL-17 inhibitors treatment, defined as the 100% improvement in Psoriasis Area and Severity Index (PASI 100). Multivariate Cox regression analyses and LASSO analysis were performed to identify clinical predictors and blood predictors respectively. RESULTS: The following parameters were identified as predictive factors associated with TSC: previous biologic treatment, joint involvement, genital area affected, early response (PASI 60 at week 4), neutrophil counts and uric acid levels. The nomogram model incorporating these factors achieved good discrimination in the development cohort (AUC, 0.721; 95% CI 0.670-0.773) and validation cohort (AUC, 0.715; 95% CI 0.665-0.760). The calibration curves exhibited a satisfactory fit, indicating the accuracy of the model. Furthermore, the decision curve analysis confirmed the clinical utility of the nomogram, highlighting its favorable value for practical application. Web-based online calculator has been developed to enhance the efficiency of clinical applications. CONCLUSIONS: This study developed a practical and clinically applicable nomogram model for the prediction of TSC in patients with moderate to severe psoriasis. The nomogram model demonstrated robust predictive performance and exhibited significant clinical utility. Trial registration A multi-center clinical study of systemic treatment strategies for psoriasis in Chinese population;ChiCTR2000036186; Registered 31 August 2020; https://www.chictr.org.cn/showproj.html?proj=58256 .

Insulin Resistance Impairs Biological Agents Response in Moderate-to-Severe Plaque Psoriasis: Insights from a Prospective Cohort Study in China.

BACKGROUND: Psoriasis and insulin resistance (IR) are closely related, but it remains unclear whether IR affects the treatment of patients with psoriasis. OBJECTIVE: The objective of this study was to investigate whether IR impairs the treatment response to biologic agents in patients with moderate-to-severe plaque psoriasis. METHODS: This project was based on a prospective cohort study design. Data for this study were collected from the Shanghai Psoriasis Effectiveness Evaluation CoHort (SPEECH), which is a prospective cohort exploring treatment strategies for psoriasis in China. IR was assessed using the triglyceride glucose-body mass index (TyG-BMI). Psoriasis severity was assessed using the Psoriasis Area and Severity Index (PASI) and Physician's Global Assessment (PGA). Multiple logistic regression was used to explore the differences between patients with high and low levels of IR. Subgroup and sensitivity analyses were performed to examine the robustness of the study results. RESULTS: A total of 290 patients were included in the analysis. Based on the median TyG-BMI, the patients were divided into two groups: High and Low. The High group exhibited a higher prevalence of diabetes, higher BMI, fasting blood glucose, and triglyceride compared with the Low group. Further analysis of the treatment efficacy revealed that the High group had lower response rates for PASI 75, PASI 90, and PGA 0/1 after 12 weeks of treatment. In the Low group, 81.94% of patients achieved PASI 75, 58.33% achieved PASI 90, and 75.69% achieved PGA 0/1. However, the proportion of responses at each endpoint was significantly lower in the High group. The impairment in response to PGA 0/1 was more significant in the High group, indicated by lower odd ratios. Subsequent subgroup analysis and sensitivity analysis produced consistent results. CONCLUSION: IR is associated with lower effectiveness of biologics in patients with psoriasis. CLINICAL TRIAL REGISTRATION: [www.chictr.org.cn], identifier [ChiCTR2000036186].

Adsorption of Cu Nanoparticles on Polystyrene-Based Microspheres.

Nanoparticle composite microspheres are a versatile material with unique features and wide-ranging applications, including catalysis, biological medicine, and electronic devices. The adsorption behavior of nanoparticles on the surface of microspheres plays a crucial role in determining the further application potentials. The understanding of nanoparticle adsorption behavior on microsphere surfaces is essential for guiding future applications in nanoparticle composite microspheres. In this work, the adsorption behavior of unstable copper nanoparticles (Cu NPs) on polystyrene-based (PS-based) microspheres was investigated. The influence of PS-based microspheres' surface properties and the oxidation degree of Cu NPs were determined. The adsorption mechanism of Cu NPs on PS-based microspheres was analyzed. Furthermore, the amounts and rates of adsorption were examined. It was found that the Cu NPs can be rapidly and firmly adsorbed on the surface of carboxyl-modified polystyrene microspheres. Additionally, precise control over the distribution of Cu NPs on the surface of PS-based microspheres can be achieved by manipulating the solvent's polarity.

Sex differences in the association between plasma polyunsaturated fatty acids levels and moderate-to-severe plaque psoriasis severity: a cross-sectional and longitudinal study.

BACKGROUND: Psoriasis is a chronic inflammatory skin disease with metabolic abnormalities serving as important contributors for pathogenesis and progression. Polyunsaturated fatty acids (PUFAs) have been found to be associated with human diseases, including psoriasis. However, differences and controversies exist regarding their content and roles. METHODS: Plasma PUFAs concentrations were measured in 296 patients with moderate-to-severe plaque psoriasis from the Shanghai Psoriasis Effectiveness Evaluation CoHort. Disease severity was assessed using Clinician-Reported Outcomes (ClinROs), including Psoriasis Area and Severity Index (PASI), Body Surface Area (BSA) and Physician Global Assessment (PGA), as well as Patient-Reported Outcomes (PROs), including Patient Global Assessment (PtGA) and Dermatology Life Quality Index (DLQI). Multivariate generalized linear regression models (GLMs), subgroup and interaction analysis, and restricted cubic spline were used to estimate the cross-sectional associations between PUFAs concentrations and disease severity. Longitudinal assessments of PASI scores and PASI response were conducted at a 12-week follow-up. Associations between baseline plasma PUFAs levels and prospective PASI scores or PASI response were assessed using multivariate GLMs or logistic regression models. RESULTS: Males suffered severer psoriasis and presented lower plasma docosahexaenoic acid (DHA) and arachidonic acid (ARA) levels compared to females. Among males, plasma eicosadienoic acid (EDA) level was positively associated with PASI, BSA and PGA scores, while total Omega-3 PUFAs and/or eicosapentaenoic acid (EPA) levels exhibited non-linear associations with PASI and/or BSA scores. α-Linolenic acid (ALA) was negatively, whereas ARA was positively, associated with DLQI scores. In females, Omega-3 PUFAs, including EPA, DHA, and total Omega-3 PUFAs, showed inverse associations with PASI and BSA scores. Longitudinally, plasma total Omega-6 PUFAs were positively associated with the likelihood of achieving PASI 100 at 12 weeks in males. In females, concentrations of dohomo-γ-linolenic acid were prospectively associated with an increase in PASI scores, and DHA was associated with the likelihood of achieving PASI 75 and PASI 90 decline. CONCLUSIONS: Sex differences cross-sectionally exist in disease severity and plasma PUFAs levels. The association between PUFAs and psoriasis severity also varies cross-sectionally and longitudinally between males and females. Sex differences should be considered when studying the function and clinical application of PUFAs in psoriasis.

The role of microRNA in psoriasis: A review.

Psoriasis is a chronic immune-mediated inflammatory skin disease that involves a complex interplay between infiltrated immune cells and keratinocytes. Great progress has been made in the research on the molecular mechanism of coding and non-coding genes, which has helped in clinical treatment. However, our understanding of this complex disease is far from clear. MicroRNAs (miRNAs) are small non-coding RNA molecules that are involved in post-transcriptional regulation, characterised by their role in mediating gene silencing. Recent studies on miRNAs have revealed their important role in the pathogenesis of psoriasis. We reviewed the current advances in the study of miRNAs in psoriasis; the existing research has found that dysregulated miRNAs in psoriasis notably affect keratinocyte proliferation and/or differentiation processes, as well as inflammation progress. In addition, miRNAs also influence the function of immune cells in psoriasis, including CD4+ T cells, dendritic cells, Langerhans cells and so on. In addition, we discuss possible miRNA-based therapy for psoriasis, such as the topical delivery of exogenous miRNAs, miRNA antagonists and miRNA mimics. Our review highlights the potential role of miRNAs in the pathogenesis of psoriasis, and we expect more research progress with miRNAs in the future, which will help us understand this complex skin disease more accurately.

Measurement properties of the patient global assessment numerical rating scale in moderate-to-severe psoriasis.

BACKGROUND: Patient global assessment (PtGA) has been recommended as one of the core domains in psoriasis clinical trials. Among multiple versions of PtGA, the single-question, 11-point PtGA numeric rating scale (NRS) remains to be validated in patients with plaque psoriasis. OBJECTIVES: To evaluate the psychometric characteristics of an 11-point PtGA NRS for disease severity in patients with moderate-to-severe plaque psoriasis. METHODS: Data were analysed from 759 patients with moderate-to-severe psoriasis in the Shanghai Psoriasis Effectiveness Evaluation CoHort (SPEECH), a prospective, multicentre and observational registry assessing the comparative effectiveness and safety of biologics (adalimumab, ustekinumab, secukinumab or ixekizumab), conventional systemic therapies (acitretin or methotrexate) and phototherapy. RESULTS: The test-retest reliability of the PtGA NRS showed good agreement (intraclass correlation coefficient range 0.79-0.83). No floor or ceiling effects of PtGA NRS were observed. The PtGA NRS was significantly correlated with the Psoriasis Area and Severity Index (PASI), static Physician Global Assessment (sPGA), body surface area, Dermatology Quality of Life Index (DLQI) and Hospital Anxiety and Depression Scale. Relatively large correlations of PtGA NRS with PASI and the DLQI 'symptoms and feelings' domain (all correlations ≥ 0.4 except at baseline) supported convergent validity. The presence of psoriatic arthritis or joint symptoms had no significant association with the PtGA NRS. In multivariate regression analyses, the PtGA NRS at baseline was predicted by age, lesion extent, lesion intensity, patients' symptoms and feelings, and impact on work or school. The PtGA NRS displayed known-groups validity with the PASI, sPGA and DLQI score bands. The PtGA NRS was responsive to change in PASI and DLQI after treatment. Anchor- and distribution-based approaches supported -3 as the minimal important difference for PtGA NRS. An absolute PtGA NRS ≤ 2 during follow-up was concordant with the state of minimal disease activity based on a 90% reduction in PASI (PASI 90) or PASI 90 plus a DLQI of 0/1. Sensitivity analysis using subgroup comparison and multiple imputation model yielded consistent conclusions. CONCLUSIONS: The PtGA NRS showed good reliability, validity and responsiveness in patients with psoriasis, and was feasible in clinical trials and daily practice.

The role of ultrasound in screening subclinical psoriatic arthritis in patients with moderate to severe psoriasis.

OBJECTIVE: To identify patients in the subclinical psoriatic arthritis (Sub-PsA) phase by ultrasound (US) and provide a solution to screen them. METHODS: A total of 490 participants with moderate-to-severe psoriasis were evaluated. Among them, 384 participants without arthritis symptoms were enrolled into the silent psoriasis group and 106 participants with arthritis symptoms, called prodromal/active PsA phase, were enrolled into the clinical PsA group. Another 80 non-psoriasis participants were enrolled into the control group. Each participant received clinical assessments and US examinations of 60 joints, 38 tendons, and 40 entheses. We compared the incidences of synovio-enthesitis, synovitis, tenosynovitis, erosion, and dactylitis detected on US among the three groups. Subsequently, on the basis of significant US findings, we distinguished Sub-PsA from psoriasis alone (PsO) in the silent psoriasis group and analyzed the clinical characteristics, mainly including basic clinical characteristics, body surface area (BSA), and Psoriasis Area and Severity Index (PASI) score. RESULTS: Only synovio-enthesitis significantly differed between the control group and the silent psoriasis group (1.3% vs. 16.1%, p < 0.001). The knee was the most commonly involved site of synovio-enthesitis (79.0%). Taking synovio-enthesitis as the standard, 16.1% of silent psoriasis participants and 12.7% of all psoriasis participants were in the Sub-PsA phase. Furthermore, there were no differences in BSA and PASI among the three phases of PsO, Sub-PsA, and prodromal/active PsA. CONCLUSIONS: Since the psoriasis patients in Sub-PsA phase was as high as 12.7% in all patients with moderate-to-severe psoriasis, US-detected synovio-enthesitis was recommended routinely for screening them regardless of arthritis symptoms, especially in the lower limbs. KEY POINTS: • Synovio-enthesitis on ultrasound was significantly associated with subclinical psoriatic arthritis, especially in the lower limbs. • Routine ultrasound evaluation could help screen psoriasis patients in the subclinical psoriatic arthritis phase, which was as high as 12.7% in all psoriasis patients.

Implications of LncRNAs and CircRNAs in psoriasis: a review.

Psoriasis is a chronic inflammatory skin disease characterized by skin infiltration of immune cells and abnormal epidermal thickening. The initial pathogenesis has not been fully elucidated. Non-coding RNAs (ncRNAs), which include long ncRNAs (lncRNAs) and circular RNAs (circRNAs), comprise the majority of genome transcripts and are important influencers of gene transcription and post-transcription modulations. Emerging roles of ncRNAs in psoriasis were identified recently. This review summarizes the existing studies of psoriasis-related lncRNAs and circRNAs. A considerable proportion of the studied lncRNAs and circRNAs regulate keratinocyte mobility, such as keratinocyte proliferation and differentiation. Some lncRNAs and circRNAs are tightly related to keratinocyte inflammation reactions. Other reports demonstrated that they are also implicated in modulating immune cell differentiation, proliferation, and activation. This review might illuminate future psoriasis research and highlight that lncRNAs and circRNAs might act as therapeutic targets.

Quality of Life Benefit and Clinical Predictors of Complete Skin Clearance in Psoriasis: A Multicenter, Prospective, Real-World Study.

BACKGROUND: Newer biologics, such as interleukin (IL)-17 inhibitors, make it possible to achieve complete skin clearance (CSC) in patients with moderate-to-severe psoriasis. However, the clinical meaningfulness and predictive factors of CSC in daily practice have not yet been fully investigated. OBJECTIVE: The study was conducted to, first, assess the impact of CSC on quality of life (QoL) improvements compared with treatment responses without clearance and, second, identify clinical parameters as predictors of CSC response in psoriasis patients treated with ixekizumab. METHODS: Patients attending 26 dermatology centers across China were recruited into this real-world setting between August 2020 and May 2022. Prospective cohort study in which response to ixekizumab was assessed using the Psoriasis Area and Severity Index (PASI) and Dermatology Quality of Life Index (DLQI). The absolute DLQI score and DLQI (0) response at week 12 were compared between groups achieving various levels of skin clearance. A stepwise logistic regression analysis was applied to identify which baseline clinical characteristics were predictive factors for CSC. RESULTS: After 12 weeks of treatment, 226 of 511 (44.2%) patients achieved CSC, defined as 100% improvement in PASI score (PASI-100). A significantly higher proportion of patients with CSC versus almost clear skin (PASI 90-99) achieved DLQI score of 0, corresponding to the experience of no impairment on QoL (54.4% vs. 37.7%, p = 0.001). Females patients were more likely than males to achieve CSC response (odds ratio [OR] = 1.83; 95% confidence interval [CI]: 1.24-2.70), while previous biologic treatment (OR = 0.43; 95% CI: 0.24-0.81) and joint affected (OR = 0.61; 95% CI: 0.42-0.89) were significantly associated with less CSC response. CONCLUSIONS: This study highlights the fact that clinical parameters are important in determining CSC response in psoriasis. In daily practice, achieving CSC represents a clinically meaningful treatment goal, especially from the patient perspective.

Human umbilical cord-derived mesenchymal stem cells ameliorate psoriasis-like dermatitis by suppressing IL-17-producing γδ T cells.

Mesenchymal stem cells (MSCs) have shown great potential in treating autoimmune diseases due to their immunomodulatory capability, which has been verified in both animal experiments and clinical trials. Psoriasis is a chronic and remitting immune-related disease. Limited studies have demonstrated that MSCs might be an effective therapeutic approach for managing psoriasis, whose underlying mechanism remains to be elucidated. In our present study, human umbilical cord-derived MSCs (hUC-MSCs) were subcutaneously injected into mice with imiquimod (IMQ)-induced psoriasis-like skin inflammation to explore the feasibility of this cellular therapy. The severity of psoriasis-like dermatitis was evaluated by cumulative psoriasis area and severity index score and epidermal thickness of skin tissue sections. Flow cytometric analysis was utilized to detect T helper cells, regulatory T cells, and γδ T cells in skin-draining lymph nodes. Real-time quantitative polymerase chain reaction and enzyme-linked immunosorbent assay were used to assess the expression levels of psoriasis-related cytokines and chemokines in mouse dorsal skin lesions. We discovered that hUC-MSCs drastically diminished the severity of IMQ-induced psoriasis-like dermatitis and suppressed inflammatory cell response. Although the tail vein injection of hUC-MSCs was also effective, it was correlated with higher mortality owing to pulmonary embolism. By comparison, subcutaneous injection with two million hUC-MSCs was identified to be the optimal therapeutic strategy. Furthermore, we uncovered that hUC-MSCs might repress skin inflammation probably through inhibiting interleukin-17-producing γδ T cells. In conclusion, subcutaneous administration of hUC-MSCs might be a promising therapeutic approach for psoriasis. Our findings provide novel insights into the underpinning mechanism of hUC-MSC treatment in the management of psoriasis.

Erythrokeratodermia variabilis et progressiva due to a novel mutation in GJB4.

Erythrokeratodermia variabilis et progressiva (EKVP) is a rare genodermatosis of clinical and genetic heterogeneity, characterized by the manifestations of localized or disseminated persistent hyperkeratotic plagues and stationary to migratory transient erythematous patches. The majority of EKVP cases display an autosomal dominant mode of inheritance with incomplete penetrance, although recessive transmission has also been described. Mutations associated with EKVP have been primarily detected in connexin (Cx) genes. We herein reported a Chinese sporadic case of late-onset EKVP with a novel heterozygous missense mutation c.109G>A (p.V37M) in GJB4 (Cx30.3) gene, which resulted in a significant reduction of GJB4 expression in the epidermis of the patient. In accordance, while wild-type GJB4 localized at the cell membrane of HeLa cells forming intercellular junctions and intracellular puncta, V37M mutant variant was diffusely expressed within HeLa cells at a considerably lower level. Our findings reveal an essential role of GJB4 in the pathogenesis of EKVP and provides insights into the therapeutic potential of the disease.

The efficacy and safety of dupilumab for the treatment of atopic dermatitis among Chinese patients in clinical practice: A single-center retrospective study.

Little real-work data regarding the efficacy and safety of dupilumab in the treatment of atopic dermatitis (AD) is available at present. To assess the efficacy and safety of dupilumab at 12 weeks in the treatment of AD in clinical routine clinical practice. A retrospective, single-centre study of adult patients with moderate to severe AD treated with dupilumab for 12 weeks in China. In total, 60 patients (48 male, 12 female; mean age: 53.2 ± 15.6) were enrolled in this retrospective study. These patients exhibited a mean AD disease course of 10.6 years (6.0), 30% exhibited a family history of allergies, and 31 (51.7%) had one or more allergic comorbidities. Following dupilumab treatment for 12 weeks, 83.3% and 42% of patients had achieved EASI-50 and EASI-75, respectively. Overall, adverse events (AEs) were reported by 15% of patients, with the most common being conjunctivitis, injection site reactions, and herpes simplex virus infections. Laboratory testing after 12 weeks revealed pronounced decreases in both circulating eosinophil counts (from 0.6 (0.1-2.8) to 0.3 (0.1-9.7) 109 /L) and total IgE concentrations (from 327 (2.46-2500) to 230 (47.6-2200) U/ml) in these patients. These real-world data reaffirm the safety and efficacy of dupilumab as a treatment for moderate-to-severe AD among Chinese patients in clinical practice.

Crosstalk between N6-methyladenosine modification and circular RNAs: current understanding and future directions.

N6-methyladenosine (m6A) is a prevalent internal modification in eukaryotic RNAs regulated by the so-called "writers", "erasers", and "readers". m6A has been demonstrated to exert critical molecular functions in modulating RNA maturation, localization, translation and metabolism, thus playing an essential role in cellular, developmental, and disease processes. Circular RNAs (circRNAs) are a class of non-coding RNAs with covalently closed single-stranded structures generated by back-splicing. CircRNAs also participate in physiological and pathological processes through unique mechanisms. Despite their discovery several years ago, m6A and circRNAs has drawn increased research interest due to advances in molecular biology techniques these years. Recently, several scholars have investigated the crosstalk between m6A and circRNAs. In this review, we provide an overview of the current knowledge of m6A and circRNAs, as well as summarize the crosstalk between these molecules based on existing research. In addition, we present some suggestions for future research perspectives.

A randomized prospective study of different dose regimens using the 308-nm excimer laser in the treatment of palmoplantar pustulosis.

The objective of this study was to evaluate optimal treatment regimen of 308-nm excimer laser for palmoplantar pustulosis (PPP). 77 patients with PPP were randomly assigned to receive low dose (2-fold of MED as initial dose), medium dose (4-fold of MED as initial dose) and high dose group (6-fold of MED as initial dose) and the MED of each patient depended on the ultraviolet light sensitivity of individual's skin which ranged from 0.1 to 0.25 J/cm2 . All group received 308-nm excimer laser treatment three times weekly for 8 weeks. Clinical evaluation based on the Palmoplantar Pustular Psoriasis Area and Severity Index (PP-PASI) and Dermatology Life Quality Index (DLQI) score. All treatment groups achieved satisfied efficacy at the end of the treatment period with more obvious reduction of PP-PASI score in high dose group (16.05 ± 4.26) than low and medium dose group (23.67 ± 7.16, p < 0.01; 22.04 ± 5.74, p < 0.01). Improvement of DLQI score was greatest at week 4 for all patients in each group, while DLQI improved more quickly in high/medium dose group than low dose group. Adverse effects of erythema, blistering and erosions were more common with the higher dose regimen. High dose of 308-nm excimer laser could achieve a better efficacy in PPP treatment, reduce the severity of the disease in patients and improve the life quality of patients. Meantime, the incidence of adverse reactions should be aware of and it's necessary to evaluate the skin and lesion type before the dose selection.

Tazarotene/Betamethasone Dipropionate Cream in Patients with Plaque Psoriasis: Results of a Prospective, Multicenter, Observational Study.

BACKGROUND: Topical agents are still the mainstay for the treatment of mild-to-moderate plaque psoriasis, in which fixed combinations play an important role. Tazarotene/betamethasone dipropionate (Taz/BD) cream is a novel fixed combination approved for treating plaque psoriasis in China, but its efficacy and safety have not been verified in a real-world environment. OBJECTIVES: The primary objective was to investigate the efficacy and safety of Taz/BD cream in treating plaque psoriasis. The secondary objectives were to assess its relapse after discontinuation and the efficacy and safety profiles during retreatment. METHODS: A prospective, multicenter, large-scale observational study was conducted. Adult patients with chronic plaque psoriasis involving <20% of the body surface area were enrolled. Taz/BD cream was applied once daily for 4 weeks. Patients who achieved ≥90% improvement in the Psoriasis Area and Severity Index (PASI) from baseline to week 4 were followed up to investigate relapse after drug withdrawal. Relapsed patients underwent another 4-week treatment. RESULTS: In total, 2,299 eligible patients were enrolled, and 2,095 patients (91.1%) completed the 4-week study. The mean PASI improvement at week 4 was 53.7%, and the PASI 50/75 response rates were 62.5 and 26.8%, respectively. The mean PASI reduction in plaque induration, desquamation and erythema were 58.3, 61.0 and 40.0%, respectively (p < 0.001). Adverse reactions occurred in 445 patients (20.8%) at week 4. The most frequently reported adverse reactions were local skin irritation, including pruritus (10%), pain (6.7%), erythema (6.1%) and desquamation (1.8%). During the post-treatment period, 47 patients (24.0%) relapsed within 8 weeks after drug discontinuation. Forty-five patients were retreated for another 4 weeks, and the PASI 50/75 response rates were 72.7 and 40.9%, respectively. There were no unexpected safety signals during retreatment. CONCLUSION: Taz/BD cream is effective and well tolerated in treating mild-to-moderate plaque psoriasis under near real-world conditions and demonstrates efficacy and safety during retreatment.

Interleukin-33 alleviates psoriatic inflammation by suppressing the T helper type 17 immune response.

Psoriasis is a chronic inflammatory skin disease with unclear pathogenesis. Interleukin-33 (IL-33) is highly expressed in patients with psoriasis, but its role in psoriasis is unknown. The aim of this study was to investigate the possible role of IL-33 in the pathogenesis and treatment of psoriasis. IL-33 expression was determined using enzyme-linked immunosorbent assay, real-time fluorescent quantitative polymerase chain reaction and immunohistochemical staining. CD4+ T cells were sorted using magnetic beads and treated with or without IL-33. Imiquimod (IMQ) was used to induce psoriatic inflammation in mice. The frequency of immune cells was determined using flow cytometry. The cytokine level in mouse skin was measured using cytometric bead array. Our results showed that IL-33 was highly expressed in the lesional skin and serum of patients with moderate-to-severe plaque psoriasis. IL-33 inhibited the expression of IL-17 in CD4+ T cells of psoriasis patients. Subcutaneous injection of IL-33 alleviated the IMQ-induced psoriatic inflammation in mice, reduced tumor necrosis factor-α and IL-23 expression, and decreased the proportion of T helper type 17 (Th17) cells in the skin-draining lymph nodes in the mice. Our results suggest that IL-33 plays a protective role in the pathogenesis of psoriasis by suppressing Th17 cell differentiation and function. The potential therapeutic effect of IL-33 in treating psoriasis warrants further investigation.