Temperature-sensitive transient receptor potential melastatin subfamily 4 (TRPM4) ion channels convert intracellular calcium increases into membrane depolarization, thereby linking these two powerful cellular signaling pathways in diverse physiological processes. TRPM4 mutations cause severe human hereditary cardiovascular and skin diseases; mysteriously, while these mutations are gain-of-function in nature, they affect the heart and the skin in a mutually exclusive manner. Here, we show that phosphatidylinositol 4,5-bisphosphate (PIP2) lipid is a required cofactor for TRPM4 activity by tightly regulating its calcium sensitivity. We detected two PIP2 binding sites and located the high-affinity site adjacent to the S4-S5 linker. We demonstrated that skin disease-associated TRPM4 mutations relieve the tight control of PIP2, resulting in elevated channel activity but only at the body surface temperature. In contrast, heart diseases are associated with mutations known to boost the number of channels, an effect we found to be annihilated by channel desensitization outside the body core. Indeed, dendritic cells from transgenic mice carrying a skin disease mutant exhibited elevated migration at 25-to-30°C range compared to those from normal mice, but no difference was observed at 37°C. These findings shed light on a molecular mechanism for dynamic regulation of cellular signaling in physiology and diseases.

Background: Colorectal cancers (CRCs) harboring the BRAFV600E (V600E) mutation exhibit aggressive clinical behavior and chemotherapy resistance, yet the underlying mechanisms remain poorly understood. Ferroptosis, which is driven by iron-dependent lipid peroxidation, has emerged as a potential therapeutic vulnerability. This study aimed to explore whether the NF-κB/Lipocalin 2 (LCN2) pathway modulates cisplatin sensitivity through Fenton-reaction-induced ferroptosis in BRAFV600E-overexpressing CRC cells. Methods: BRAF mutation status and the expression of LCN2, PTGS2, and cleaved caspase3 were examined in clinical CRC specimens by immunohistochemistry. The correlations between ferroptosis and apoptosis markers and 5-year survival rate were evaluated in TCGA datasets. CRC cells with LCN2 knockdown/knockout or BRAF/V600E/LCN2 overexpression were established to assess the proliferation, lipid metabolism, iron levels, and NF-κB/LCN2 signaling under cisplatin treatment. In vivo studies were employed with BALB/c xenograft models. Results: V600E-mutant clinical specimens exhibit significantly reduced expression of the ferroptosis marker PTGS2, and the iron metabolism regulators LCN2. Within a KRAS-mutant cellular model, V600E overexpression attenuated cisplatin-induced ferroptosis through suppression of the NF-κB/LCN2 signaling axis, leading to impairment of Fenton-reaction-mediated lipid peroxidation. Restoration of LCN2 expression re-sensitized V600E-overexpressing cells to cisplatin both in vitro and in vivo. Interestingly, inhibition of apoptosis contributes to the resistance of cisplatin induced ferroptosis in V600E overexpression cells, implying a crosstalk between ferroptosis and apoptosis within the therapeutic resistance. Conclusions: Our findings show that the NF-κB/LCN2 axis drives Fenton-reaction-induced ferroptosis to promote the vulnerability of V600E overexpression CRC cells within a KRAS-mutant background to cisplatin. LCN2 restoration partially overcomes V600E overexpression resistance both in vitro and in vivo, suggesting LCN2 as a promising therapeutic target. The crosstalk between ferroptosis and apoptosis may offer potential strategies to overcome chemotherapy resistance of this high-risk CRC subtype.

Although diet has been regarded as a potential environmental risk factor for psoriasis, the precise contribution of specific dietary components, such as sugar, to its pathogenesis remains uncertain. Metformin, a primary medication for type II diabetes mellitus, has been documented to yield improvements in psoriasis. Earlier research indicates that the antihyperglycemic impact of metformin is associated with changes in gut microbiota. Nonetheless, the role of gut microbiota in the antipsoriatic effects of metformin remains unclear. In this study, we showed that 4 weeks of glucose intake exacerbated psoriasiform dermatitis (PsD) in mice, which resolved with oral metformin treatment. The exacerbation and resolution of PsD were mediated through effects on the gut microbiota. Supplementation with Akkermansia muciniphila, enriched by metformin, or Amuc_1100 improved PsD in glucose-fed mice but not in the control mice. Glucose intake resulted in reduced serum levels of indole-3-acetic acid, a microbial tryptophan metabolite, which were reversed by A muciniphila and Amuc_1100 treatment. Oral administration and intradermal injection of indole-3-acetic acid protected mice from glucose-promoted PsD with suppressed expression of antimicrobial peptides, specifically S100A8, in the epidermis. Collectively, increases of A muciniphila through metformin treatment led to reversal of glucose-promoted PsD in mice, possibly through production of the microbial tryptophan metabolite indole-3-acetic acid.

Psoriasis is a chronic inflammatory skin disease marked by abnormal keratinocyte growth, immune dysfunction, and a weakened skin barrier. Affecting 2-3% of the global population, it lowers quality of life and is linked to systemic conditions. Though treatments have improved, many patients still lack effective options. Recent research emphasizes the critical role of ion channels, especially cation channels, in psoriasis. These channels influence keratinocyte proliferation, differentiation, immune responses, and apoptosis. Dysregulation of calcium, potassium, sodium, and chloride channels contributes to inflammation, skin barrier issues, and keratinocyte malfunction. For instance, transient receptor potential channels affect inflammation and differentiation, while voltage-gated potassium channels impact immune cell activity and cytokine release. This review summarizes how cation channels contribute to psoriasis and highlights their therapeutic potential, offering new directions for targeted treatments aimed at restoring skin integrity and reducing inflammation.

Cisplatin is a widely used anti-cancer drug.Unfortunately, many cancers often develop resistance, which contributes to tumor recurrence and poorly prognosis.Growing knowledge has suggested the therapeutic potential of ferroptosis in cancer.Lipocalin2 (LCN2) is demonstrated to be a critical iron metabolic factor and implies in ferroptosis.Here, we aim to explore its role in chemotherapy resistance.The influence of LCN2 on colorectal cancer (CRC) cell chemoresistance and ferroptosis were evaluated by in vitro and in vivo approaches.The interaction between LCN2, NF-ĸB and ferroportin (FPN) was assessed by western blots, immunohistochemistry and dual luciferase reporter assays.Results showed that LCN2 was highly expressed in tumor regression grade 1 (TRG1) cases than that in TRG3 specimens.Loss of LCN2 contributed to resistance to cisplatin-induced ferroptosis.Mechanistically, loss of LCN2 inhibited cisplatin sensitivity and cisplatin-induced ferroptosis through elevating FPN expression which was regulated by NF-ĸB, subsequently reducing Fe 2+ mediated Fenton reaction.Furthermore, FPN expression rate was much lower in TRG1 cases, and negative correlation between LCN2 and FPN expression was observed in clinical specimens.Collectively, low LCN2 expression enhances insensitivity of cisplatin to CRC cells via Fenton reaction mediated ferroptosis.LCN2/NF-ĸB/FPN pathway might be potentially utilized for chemoresistance strategy.LCN2 and FPN expression might be a promising biomarker of chemotherapy effect for CRC patients.

Several inflammatory cytokines bind to the allosteric site (site 2) and allosterically activate integrins. Site 2 is also a binding site for 25-hydroxycholesterol, an inflammatory lipid mediator, and is involved in inflammatory signaling (e.g., TNF and IL-6 secretion) in addition to integrin activation. FGF2 is pro-inflammatory and pro-thrombotic, and FGF1, homologous to FGF2, has anti-inflammatory and anti-thrombotic actions, but the mechanism of these actions is unknown. We hypothesized that FGF2 and FGF1 bind to site 2 of integrins and regulate inflammatory signaling. Here, we describe that FGF2 is bound to site 2 and allosterically activated β3 integrins, suggesting that the pro-inflammatory action of FGF2 is mediated by binding to site 2. In contrast, FGF1 bound to site 2 but did not activate these integrins and instead suppressed integrin activation induced by FGF2, indicating that FGF1 acts as an antagonist of site 2 and that the anti-inflammatory action of FGF1 is mediated by blocking site 2. A non-mitogenic FGF1 mutant (R50E), which is defective in binding to site 1 of αvβ3, suppressed β3 integrin activation by FGF2 as effectively as WT FGF1.

Psoriasis, an immune-mediated inflammatory skin disorder characterized by a chronically relapsing-remitting course, continues to be primarily managed through topical therapy. While oral administration of tyrosine kinase 2 inhibitors (TYK2i) stands as an effective approach for psoriasis treatment, the potential efficacy of topical application of TYK2i remains unexplored. Herein, the carbomer/alginic acid hydrogel is embedded with borneol (BO) as a new topical carrier of TYK2i for achieving enhanced transdermal permeation and anti-psoriasis efficacy. The hydrogel system, i.e., TYK2i-BO-gel, exhibits significantly improved preventative and therapeutic effects in mice models of psoriasiform dermatitis, as evidenced by phenotypical images, psoriasis severity score index (PSI), histology, immunohistochemical staining, and PCR analysis. Remarkably, TYK2i-BO-gel outperforms conventional topical corticosteroid therapy by significantly preventing psoriatic lesion recurrence as measured by a nearly 50 % reduction in ear thickness changes (p < 0.0001), PSI (p < 0.0001) and epidermal thickness (p < 0.05). Moreover, a strengthened anti-inflammatory effect caused by TYK2i-BO-gel is seen in a human skin explant model, implying its potential application for human patients. With the addition of BO, the TYK2i-BO-gel not only increases skin permeability but also inhibits the expression of antimicrobial peptides in keratinocytes and facilitates the anti-Th17 response of TYK2i with suppressed activation of STAT3. Therefore, this work represents the accessibility and effectiveness of TYK2i-BO-hydrogel as a new topical formulation for antipsoriasis management and shows great potential for clinical application.

Psoriasis is an inflammatory disease that is initiated by pathogenic T cells within skin lesions that correlates with hyperproliferation of keratinocytes and the release of cytokines and damage-associated molecular pattern molecules into the circulation (Wang and Jin, 2020). Exposure to damage-associated molecular patterns and low levels of cytokines and chemokines shift neutrophils from a quiescent to a primed state characterized by increased sensitivity to subsequent stimulation that induces amplified adhesive and effector function at sites of tissue inflammation (Miralda et al, 2017).

Background Chemokines represent a superfamily of immune-modulatory small protein molecules that regulate leukocyte migration to inflammatory sites through their chemoattractant and cell signaling properties. This review focuses on the immunological functions of the CCR6 chemokine receptor and is chemokine ligand, CCL20, that contribute to it role in inflammation in human psoriasis. Methods Peer-reviewed relevant articles are searched and selected from 2000 to 2022 using the search engines including PubMed and Google Scholar. Results After selectively reviewing and evaluating over seventy articles, a comprehensive overview on the immunology of CCL20-CCR6 axis in psoriasis and psoriatic arthritis, the X-ray crystal structures of CCL20 monomers, and the potential of developing clinical therapies targeting this axis is summarized. Conclusions Over the past decade, preclinical studies carried out in animal models of psoriasis involving agents targeting CCL20-CCR6 axis have yielded promising results. Other studies that this axis may play a role in a number of other autoimmune diseases, including rheumatoid arthritis, suggesting a rationale for further investigation into this key signaling/migratory pathway.

Background Bile acids (BAs) are cholesterol-based amphipathic surfactants that are most widely known for their contributions to lipid metabolism, but more recently have been increasingly recognized as a key signaling molecule in inflammatory diseases as well as, potentially, psoriatic disease. Objective This brief review reviews relevant literature in order to briefly describe the synthesis of bile acids and their subsequent metabolism and to analyze recent animal and human data that supports anti-inflammatory activity of some BAs in psoriasiform dermatitis. Methods Pubmed and other public sources were used to survey the literature relevant to the topic of bile acids and their potential use in psoriasis. Conclusion There is clinical and preclinical evidence to support a potential role for BA Supplementation (or modulation BA metabolism and signaling) in the treatment of psoriasis.

MicroRNA-22 (miR-22) can be induced by beneficial metabolites that have metabolic and immune effects, including retinoic acids, bile acids, vitamin D3, and short-chain fatty acids. The tumor suppressor effects of miR-22 have been suggested, but whether miR-22 treats orthotopic hepatocellular carcinoma (HCC) is not established. The role of miR-22 in regulating tumor immunity is also poorly understood. Our data showed that miR-22 delivered by adeno-associated virus serotype 8 effectively treated HCC. Compared with FDA-approved lenvatinib, miR-22 produced better survival outcomes without noticeable toxicity. miR-22 silenced hypoxia-inducible factor 1 (HIF1a) and enhanced retinoic acid signaling in both hepatocytes and T cells. Moreover, miR-22 treatment improved metabolism and reduced inflammation. In the liver, miR-22 reduced the abundance of IL17-producing T cells and inhibited IL17 signaling by reducing the occupancy of HIF1a in the Rorc and Il17a genes. Conversely, increasing IL17 signaling ameliorated the anti-HCC effect of miR-22. Additionally, miR-22 expanded cytotoxic T cells and reduced regulatory T cells (Treg). Moreover, depleting cytotoxic T cells also abolished the anti-HCC effects of miR-22. In patients, miR-22 high HCC had upregulated metabolic pathways and reduced IL17 pro-inflammatory signaling compared with miR-22 low HCC. Together, miR-22 gene therapy can be a novel option for HCC treatment.

The transcription factor nuclear factor-κB (NF-κB) plays a complicated role in multiple tumors. Mounting evidence demonstrates that NF-κB activation supports tumorigenesis and development by enhancing cell proliferation, invasion, and metastasis, preventing cell death, facilitating angiogenesis, regulating tumor immune microenvironment and metabolism, and inducing therapeutic resistance. Notably, NF-κB functions as a double-edged sword exerting positive or negative influences on cancers. In this review, we summarize and discuss recent research on the regulation of NF-κB in cancer cell deaths, therapy resistance, and NF-κB-based nano delivery systems.

Context:The expression of programmed cell death ligand1 (PDL1) is a research hotspot of immunotherapy. The treatment targeted for its expression has shown effectiveness in many tumors. Objective:The aim of the study was to determine PD-L1 expression in urothelial carcinoma (UC) and to compare the PD-L1 expression in muscle invasive bladder carcinoma (MIBC) and upper urinary tract urothelial carcinoma (UTUC). The predictive value of CD8+ tumor-infiltrating lymphocyte (TIL) density for the diagnosis of PD-L1 positivity and the association between CD8+ TIL density and prognosis in MIBC were also explored. Materials and Methods:Immunohistochemistry (IHC) staining for PD-L1 (SP263), CK5/6, CK20, CD44, and p53 was carried out using a 3D Histech digital scanner to scan and determine CD8+ TIL density. Results:122 patients received radical cystectomy, and the overall PD-L1 positivity was 34.43% (42/122). PD-L1 positivity in whole sections was higher than in tissue micro-array (TMA) (all P < 0.05). If multiple lesions were detected simultaneously, the number of patients with positive results increased from 42 to 49. The areas under the curve (AUCs) of CD8+ TIL density for the diagnosis of PD-L1 positivity were 0.739, 0.713, and 0.826. Univariate cox regression analysis demonstrated that high CD8+ TIL density and CD8highPDL1+ were protective factors of overall survival (OS), and multivariate cox analyses showed that only CD8+ TIL density was an independent prognostic factor for OS. For UTUC, the overall PD-L1 expression was 40.0% (16/40). Conclusions:Our study results emphasize the importance of detecting PD-L1 expression in multiple tumor lesions from the same patient. In MIBC, CD8+ TIL density could be used as a prognostic marker for predicting the status of PD-L1 expression.

There is growing evidence that supports a role of gut dysbiosis in the pathogenesis of psoriasis (Pso). Thus, probiotic supplementation and fecal microbiota transplantation may serve as promising preventive and therapeutic strategies for patients with Pso. One of the basic mechanisms through which the gut microbiota interacts with the host is through bacteria-derived metabolites, usually intermediate or end products produced by microbial metabolism. In this study, we provide an up-to-date review of the most recent literature on microbial-derived metabolites and highlight their roles in the immune system, with a special focus on Pso and one of its most common comorbidities, psoriatic arthritis.

A novel engineered CCL20 locked dimer (CCL20LD) is nearly identical to the naturally occurring chemokine CCL20 but blocks CCR6-mediated chemotaxis and offers a new approach to treat the diseases of psoriasis and psoriatic arthritis. Methods for quantifying CCL20LD serum levels are needed to assess pharmacokinetics parameters and evaluate drug delivery, metabolism, and toxicity. Existing ELISA kits fail to discriminate between CCL20LD and the natural chemokine, CCL20WT (the wild type monomer). Herein, we tested several available CCL20 monoclonal antibodies to be able to identify one clone that can be used both as a capture and a detection antibody (with biotin-labeling) to specifically detect CCL20LD with high specificity. After validation using recombinant proteins, the CCL20LD-selective ELISA was used to analyze blood samples from CCL20LD treated mice, demonstrating the utility of this novel assay for preclinical development of a biopharmaceutical lead compound for psoriatic disease.

Transient receptor potential melastatin 4 (TRPM4) is a Ca2+-activated, monovalent cation channel that is expressed in a wide range of cells. We previously reported two gain-of-function (GoF) mutations of TRPM4 as the cause of progressive symmetric erythrokeratodermia (PSEK), which shares similar clinical and histopathological features with psoriasis. Using CRISPR/Cas9 technology, we generated TRPM4I1029M mice that have the equivalent mutation to one of the two genetic mutations found in human PSEK (equivalent to human TRPM4I1033M). Using this mutant mice, we examined the effects of TRPM4 GoF at the cellular and phenotypic levels to elucidate the pathological mechanisms underlying PSEK. In the absence of experimental stimulation, TRPM4I1029M mice did not show a phenotype. When treated with imiquimod (IMQ), however, TRPM4I1029M mice were predisposed to more severe psoriasiform dermatitis (PsD) than wild-type (WT), which was characterized by greater accumulation of CCR6-expressing γδ T cells and higher mRNA levels of Il17a. In TRPM4I1029M mice, dendritic cells showed enhanced migration and keratinocytes exhibited increased proliferation. Moreover, a TRPM4 inhibitor, glibenclamide, ameliorated PsD in WT and TRPM4I1029M mice. Our results indicate elevated TRPM4 activities boosted susceptibility to cutaneous stimuli, likely through elevation of membrane potential and alteration of downstream cellular signaling, resulting in enhanced inflammation. Our results further suggest a possible therapeutic application of TRPM4 inhibitors in psoriasis.

BackgroundMolecular information about bladder cancer is significant for treatment and prognosis. The immunohistochemistry (IHC) method is widely used to analyze the specific biomarkers to determine molecular subtypes. However, procedures in IHC and plenty of reagents are time and labor-consuming and expensive. This study established a computer-aid diagnosis system for predicting molecular subtypes, p53 status, and programmed death-ligand 1 (PD-L1) status of bladder cancer with pathological images. Materials and MethodsWe collected 119 muscle-invasive bladder cancer (MIBC) patients who underwent radical cystectomy from January 2016 to September 2018. All the pathological sections are scanned into digital whole slide images (WSIs), and the IHC results of adjacent sections were recorded as the label of the corresponding slide. The tumor areas are first segmented, then molecular subtypes, p53 status, and PD-L1 status of those tumor-positive areas would be identified by three independent convolutional neural networks (CNNs). We measured the performance of this system for predicting molecular subtypes, p53 status, and PD-L1 status of bladder cancer with accuracy, sensitivity, and specificity. ResultsFor the recognition of molecular subtypes, the accuracy is 0.94, the sensitivity is 1.00, and the specificity is 0.909. For PD-L1 status recognition, the accuracy is 0.897, the sensitivity is 0.875, and the specificity is 0.913. For p53 status recognition, the accuracy is 0.846, the sensitivity is 0.857, and the specificity is 0.750. ConclusionOur computer-aided diagnosis system can provide a novel and simple assistant tool to obtain the molecular subtype, PD-L1 status, and p53 status. It can reduce the workload of pathologists and the medical cost.

Bile acids (BAs), produced in the liver and further transformed in the gut, are cholesterol-derived molecules involved in essential physiological processes. Recent studies suggest that BAs regulate T helper 17 cell function, but the underlying mechanism of this action and their therapeutic value in disease models remains unclear. Using an IL-23 minicircle DNA-based murine model of psoriasiform dermatitis, we showed that oral administration of secondary BAs, including lithocholic acid (LCA), deoxycholic acid, and 3-oxoLCA, significantly improved psoriasiform dermatitis without inducing apparent hepatotoxicity. Of the BAs tested, LCA possessed the greatest potency in treating psoriasiform dermatitis. Intravenous administration of LCA at a much lower dosage (compared with oral treatment) showed a comparable antipsoriatic effect and markedly suppressed the IL-17A response. Ex vivo experiments revealed that LCA reduced IL-17A production in IL-23-stimulated murine T cells in the absence of BA receptors TGR5 or FXR. Strikingly, BAs inhibited CCL20 expression in keratinocytes, which led to reduced migration of CCR6-expressing Jurkat cells cultured in the conditioned medium of stimulated keratinocytes. Thus, BAs improve psoriasiform dermatitis with minimal toxicity via direct inhibition of IL-17A production and blockade of CCL20-mediated trafficking, supporting the potential use of BAs in psoriasis.