Keratinocyte Proliferation Research Articles

Pivotal Role of mTOR in Non-Skin Manifestations of Psoriasis.

Psoriasis is a chronic inflammatory condition affecting 2% of the Western population. It includes diverse manifestations influenced by genetic predisposition, environmental factors, and immune status. The sustained activation of mTOR is a key element in psoriasis pathogenesis, leading to an uncontrolled proliferation of cytokines. Furthermore, mTOR activation has been linked with the transition from psoriasis to non-skin manifestations such as psoriatic arthritis and cardiovascular events. While therapies targeting pro-inflammatory cytokines have shown efficacy, additional pathways may offer therapeutic potential. The PI3K/Akt/mTOR pathway, known for its role in cell growth, proliferation, and metabolism, has emerged as a potential therapeutic target in psoriasis. This review explores the relevance of mTOR in psoriasis pathophysiology, focusing on its involvement in cutaneous and atheromatous plaque proliferation, psoriatic arthritis, and cardiovascular disease. The activation of mTOR promotes keratinocyte and synovial cell proliferation, contributing to plaque formation and joint inflammation. Moreover, mTOR activation may exacerbate the cardiovascular risk by promoting pro-inflammatory cytokine production and dysregulation lipid and glucose metabolism. The inhibition of mTOR has shown promise in preclinical studies, reducing skin inflammation and plaque proliferation. Furthermore, mTOR inhibition may mitigate cardiovascular risk by modulating cholesterol metabolism and attenuating atherosclerosis progression. Understanding the role of mTOR in psoriasis, psoriatic arthritis, and cardiovascular disease provides insight into the potential treatment avenues and sheds light on the complex interplay of the immune and metabolic pathways in these conditions.

In Vitro and In Vivo Antipsoriatic Efficacy of Protected and Unprotected Sugar-Zinc Phthalocyanine Conjugates.

Psoriasis, a chronic immune-mediated skin disorder affecting over 125 million people globally, is characterized by abnormal keratinocyte proliferation and immune cell infiltration. Photodynamic therapy (PDT) remains underutilized in the treatment of psoriasis despite its potential as a promising and effective therapeutic approach. This study aimed to explore the efficacy of zinc phthalocyanine (ZnPc) and its sugar conjugates as potential antipsoriatic agents. We successfully synthesized protected and unprotected sugar-conjugated zinc phthalocyanines and evaluated their potential against cytokine-stimulated HaCaT keratinocytes, as well as an established IMQ psoriasis-like in vivo model. Tetrasubstituted protected glucose-ZnPc (Glu-4-ZnPc-P) demonstrated superior phototoxicity (IC50 = 2.55 µM) compared to unprotected glucose conjugate (IC50 = 22.7 µM), protected galactose-ZnPc (IC50 = 7.13 µM), and free ZnPc in cytokine-stimulated HaCaT cells (IC50 = 5.84 µM). Cellular uptake analysis revealed that IL-17A, a cytokine that plays a central role in the pathogenesis of psoriasis, enhanced unprotected Glu-4-ZnPc uptake by 56.3%, while GLUT1 inhibitor BAY-876 reduced its accumulation by 23.8%. Intracellular ROS generation following Glu-4-ZnPc-P-PDT was significantly increased after stimulation with IL-17A, correlating with in vitro photocytotoxicity. In vivo PDT using Glu-4-ZnPc-P exhibited significant improvement in Psoriasis Area and Severity Index (PASI), inhibiting splenomegaly and restoring normal skin morphology. This study highlights sugar-conjugated zinc phthalocyanines as potential candidates for targeted PDT in psoriasis, providing a basis for further clinical investigations.

Biodegradable Silk Fibroin Matrices for Wound Closure in a Human 3D Ex Vivo Approach.

In this study, the potential of silk fibroin biomaterials for enhancing wound healing is explored, focusing on their integration into a human 3D ex vivo wound model derived from abdominoplasties. For this purpose, cast silk fibroin membranes and electrospun nonwoven matrices from Bombyx mori silk cocoons were compared to untreated controls over 20 days. Keratinocyte behavior and wound healing were analyzed qualitatively and quantitatively by histomorphometric and immune histochemical methods (HE, Ki67, TUNEL). Findings reveal rapid keratinocyte proliferation on both silk fibroin membrane and nonwoven matrices, along with enhanced infiltration in the matrix, suggesting improved early wound closure. Silk fibroin membranes exhibited a significantly improved early regeneration, followed by nonwoven matrices (p < 0.05) compared to untreated wounds, resulting in the formation of multi-layered epidermal structures with complete regeneration. Overall, the materials demonstrated excellent biocompatibility, supporting cell activity with no signs of increased apoptosis or early degradation. These results underscore silk fibroin's potential in clinical wound care, particularly in tissue integration and re-epithelialization, offering valuable insights for advanced and-as a result of the electrospinning technique-individual wound care development. Furthermore, the use of an ex vivo wound model appears to be a viable option for pre-clinical testing.

Sappanone A ameliorated imiquimod-induced psoriasis-like dermatitis in BALB/c mice via suppressing Mmp8 expression and IL-17 signaling pathway

Psoriasis is a prevalent immune-mediated inflammatory skin disease characterized by excessive abnormal proliferation of keratinocytes and infiltration of immune cells, which have significant impact on the life quality of individuals. Although biological agents and small molecule targeted drugs have brought significant clinical benefits to psoriasis patients, adverse reactions and high prices remains key issues in clinical medication of psoriasis, while natural product monomers possess high efficiency, low toxicity, anti-inflammatory and immunomodulatory properties, and bring new hope for the clinical treatment of psoriasis. Sappanone A (SA), a small molecule compound isolated from Caesalpinia sappan L, exhibits significant anti-inflammatory properties in various models, such as kidney inflammation and LPS-induced mice inflammation. Among these effects, the anti-inflammatory property of SA has received significant attention. In our study, we found that SA exhibited anti-proliferation and anti-inflammatory effects in HaCaT cells, and significantly alleviated imiquimod-induced psoriasis-like skin lesions via the inhibition of the excessive proliferation of keratinocytes and the infiltration of lymphocytes. Furthermore, the combinational analysis of network pharmacology and transcriptome sequencing revealed that SA exerted anti-psoriasis effects by inhibiting the matrix metalloproteinase 8 (Mmp8) expression and IL-17 pathway activation. In summary, we have first demonstrated that SA can be used as a novel anti-psoriasis drug, which may provide a novel strategy for the clinical treatment of psoriasis.

LncRNA MIR181A2HG inhibits keratinocytes proliferation through miR-223-3p/SOX6 axis.

Psoriasis is a complex and recurrent chronic inflammatory skin disease, and the abnormal proliferation of keratinocytes plays a crucial role in the pathogenesis of psoriasis. Long non-coding RNAs (lncRNAs) play an indispensable role in regulating cellular functions. This research aims to explore the potential impact of lncRNA MIR181A2HG on the regulation of keratinocyte proliferation. The expression level of MIR181A2HG and the mRNA level of KRT6, KRT16, and SOX6 were assessed using qRT-PCR. The viability and proliferation of keratinocytes were evaluated using CCK-8 and EdU assays. Cell cycle analysis was performed using flow cytometry. Dual-luciferase reporter assays were applied to test the interaction among MIR181A2HG/miR-223-3p/SOX6. Protein level was detected by Western blotting analysis. The findings indicated that psoriasis lesions tissue exhibited lower levels of MIR181A2HG expression compared to normal tissue. The overexpression of MIR181A2HG resulted in the inhibition of HaCaT keratinocytes proliferation. The knockdown of MIR181A2HG promoted cell proliferation. The dual-luciferase reporter assay and rescue experiments provided evidence of the interaction among MIR181A2HG, SOX6, and miR-223-3p. The lncRNA MIR181A2HG functions as a miR-223-3p sponge targeting SOX6 to regulate the proliferation of keratinocytes, which suggested that MIR181A2HG/miR-223-3p/SOX6 might be potential diagnostic and therapeutic targets for psoriasis.

Current strategies for the management of psoriasis with potential pharmacological pathways using herbals and immuno-biologicals.

Psoriasis is an acute to chronic multifunctional inflammatory skin disorder mediated through T-cell activation, dendritic cell intervention, local vascular variations, atypical keratinocyte proliferation, and neutrophil activation, leading to a skin disorder with no permanent cure. This review aims to find a potent, secure, and dependable medication, with a more scientific examination of herbal resources and recent targeted immunobiological therapies. Reports evaluating the effectiveness of biologics & herbal remedies for the topical therapy of psoriasis against control therapies were taken into consideration (placebo or active therapy). The work examined cellular circuits involved in inflammation with its immunogenetic mechanism behind various options available for treating psoriasis in addition to the role of agents inducing psoriasis. The extent of psoriasis can range from small, localized spots to total body coverage, and it can happen at any stage of life. Several theories exist for clarification however, the exact cause of psoriasis is not entirely understood. Researchers have discovered genetic loci linkages, environmental changes, drug induction, lifestyle conditions, some infections, etc. resulting in this disorder. There are numerous known conventional medical treatments for psoriasis, ranging from topical and systemic medicines to phototherapy or combinations of both with recent immunobiological treatment. However, the majority of these treatments are ineffective and have a variety of side effects that limit their long-term usage, such as cutaneous atrophy, tissue toxicity, mutagenicity, and immunosuppression. Herbal extracts or isolated compounds can be considered as a substitute for conventional psoriasis treatment. Unfortunately, many investigations often provide a small amount of facts about the safety and effectiveness of topically applied herbal remedies for the treatment of psoriasis. Thus, further factual evidences and validations are needed to promote herbal options, which must be supported by rigorous animal studies or clinical trials using standardised materials and compositions.

Granzyme K mediates IL-23-dependent inflammation and keratinocyte proliferation in psoriasis.

Psoriasis is an inflammatory disease with systemic manifestations that most commonly presents as itchy, erythematous, scaly plaques on extensor surfaces. Activation of the IL-23/IL-17 pro-inflammatory signaling pathway is a hallmark of psoriasis and its inhibition is key to clinical management. Granzyme K (GzmK) is an immune cell-secreted serine protease elevated in inflammatory and proliferative skin conditions. In the present study, human psoriasis lesions exhibited elevated GzmK levels compared to non-lesional psoriasis and healthy control skin. In an established murine model of imiquimod (IMQ)-induced psoriasis, genetic loss of GzmK significantly reduced disease severity, as determined by delayed plaque formation, decreased erythema and desquamation, reduced epidermal thickness, and inflammatory infiltrate. Molecular characterization in vitro revealed that GzmK contributed to macrophage secretion of IL-23 as well as PAR-1-dependent keratinocyte proliferation. These findings demonstrate that GzmK enhances IL-23-driven inflammation as well as keratinocyte proliferation to exacerbate psoriasis severity.

FBP1 orchestrates keratinocyte proliferation/differentiation and suppresses psoriasis through metabolic control of histone acetylation

Keratinocyte proliferation and differentiation in epidermis are well-controlled and essential for reacting to stimuli such as ultraviolet light. Imbalance between proliferation and differentiation is a characteristic feature of major human skin diseases such as psoriasis and squamous cell carcinoma. However, the effect of keratinocyte metabolism on proliferation and differentiation remains largely elusive. We show here that the gluconeogenic enzyme fructose-1,6-bisphosphatase 1 (FBP1) promotes differentiation while inhibits proliferation of keratinocyte and suppresses psoriasis development. FBP1 is identified among the most upregulated genes induced by UVB using transcriptome sequencing and is elevated especially in upper epidermis. Fbp1 heterozygous mice exhibit aberrant epidermis phenotypes with local hyperplasia and dedifferentiation. Loss of FBP1 promotes proliferation and inhibits differentiation of keratinocytes in vitro. Mechanistically, FBP1 loss facilitates glycolysis-mediated acetyl-CoA production, which increases histone H3 acetylation at lysine 9, resulting in enhanced transcription of proliferation genes. We further find that the expression of FBP1 is dramatically reduced in human psoriatic lesions and in skin of mouse imiquimod psoriasis model. Fbp1 deficiency in mice facilitates psoriasis-like skin lesions development through glycolysis and acetyl-CoA production. Collectively, our findings reveal a previously unrecognized role of FBP1 in epidermal homeostasis and provide evidence for FBP1 as a metabolic psoriasis suppressor.

Nuclear receptors for epidermal lipid barrier: Advances in mechanisms and applications.

The skin plays an essential role in preventing the entry of external environmental threats and the loss of internal substances, depending on the epidermal permeability barrier. Nuclear receptors (NRs), present in various tissues and organs including full-thickness skin, have been demonstrated to exert significant effects on the epidermal lipid barrier. Formation of the lipid lamellar membrane and the normal proliferation and differentiation of keratinocytes (KCs) are crucial for the development of the epidermal permeability barrier and is regulated by specific NRs such as PPAR, LXR, VDR, RAR/RXR, AHR, PXR and FXR. These receptors play a key role in regulating KC differentiation and the entire process of epidermal lipid synthesis, processing and secretion. Lipids derived from sebaceous glands are influenced by NRs as well and participate in regulation of the epidermal lipid barrier. Furthermore, intricate interplay exists between these receptors. Disturbance of barrier function leads to a range of diseases, including psoriasis, atopic dermatitis and acne. Targeting these NRs with agonists or antagonists modulate pathways involved in lipid synthesis and cell differentiation, suggesting potential therapeutic approaches for dermatosis associated with barrier damage. This review focuses on the regulatory role of NRs in the maintenance and processing of the epidermal lipid barrier through their effects on skin lipid synthesis and KC differentiation, providing novel insights for drug targets to facilitate precision medicine strategies.

Electric fields reverse the differentiation of keratinocyte monolayer by down-regulating E-cadherin through PI3K/AKT/Snail pathway

Re-epithelialization is an important step in skin wound healing, referring to the migration, proliferation, and differentiation of keratinocytes around the wound. During this process, the edges of the wound begin to form new epithelial cells, which migrate from the periphery of the wound towards the center, gradually covering the entire wound area. These newly formed epithelial cells proliferate and differentiate, ultimately forming a protective layer over the exposed dermal surface. Wound endogenous electric fields (EFs) are known as the dominant factor to facilitate the epidermal migration to wound center. However, the precise mechanisms by which EFs promote epidermal migration remains elusive. Here, we found that in a model of cultured keratinocyte monolayer in vitro, EFs application reversed the differentiation of cells, as indicated by the reduction of the early differentiation markers K1 and K10. Genetic manipulation confirmed that EFs reversed keratinocyte differentiation through down-regulating the E-cadherin-mediated adhesion. By RNA-sequencing analysis, we screened out Snail as the transcription suppressor of E-cadherin. Snail knockdown abolished the down-regulation of E-cadherin and the reversal of differentiation induced by EFs. KEGG analysis identified PI3K/AKT signaling for Snail induction under EFs. Inhibition of PI3K by LY294002 diminished the EFs-induced AKT activation and Snail augmentation, largely restoring the level of E-cadherin reduced by EFs. Finally, in model of full-thickness skin wounds in pigs, we found that weakening of the wound endogenous EFs by the direction-reversed exogenous EFs resulted in an up-regulation of E-cadherin and earlier differentiation in newly formed epidermis in vivo. Our research suggests that electric fields (EFs) decrease E-cadherin expression by suppressing the PI3K/AKT/Snail pathway, thereby reversing the differentiation of keratinocytes. This discovery provides us with new insights into the role of electric fields in wound healing. EFs intervene in intracellular signaling pathways, inhibiting the expression of E-cadherin, which results in a lower differentiation state of keratinocytes. In this state, keratinocytes exhibit increased migratory capacity, facilitating the migration of epidermal cells and wound reepithelialization.

The Perspective of Cannabidiol in Psoriasis Therapy.

Psoriasis is a chronic skin condition that can significantly impact the quality of life of those affected. As an autoimmune disease, it can lead to itchy, painful, and scaly patches on the skin. Although various treatments, including topical creams, phototherapy, and systemic medications, are currently available, they may not always offer effective relief and can have side effects. Researchers have thus been exploring the potential benefits of non-psychoactive compounds such as CBD, found in Cannabis sativa plants, for treating psoriasis. CBD treatment may reduce inflammation, oxidative stress, itching, abnormal proliferation of keratinocytes, and may increase hydration. This review aims to provide an overview of the existing literature on the potential uses of CBD for psoriasis treatment.

C10orf99 regulates angiogenesis by regulating VEGF and MMP2 in psoriasis

AbstractBackgroundPsoriasis is a common chronic inflammatory skin disease characterized by epidermal hyperplasia, inflammatory cell infiltration and excessive neovascularization. It was previously found that C10orf99 regulates keratinocyte proliferation and inflammation in psoriasis. However, the role of C10orf99 on angiogenesis associated with psoriasis is unknown.MethodsWe used imiquimod (IMQ)‐induced psoriasis mice and M5‐induced cellular model of psoriasis to research the effects of C10orf99 knockdown on angiogenesis in psoriasis in vivo and in vitro.ResultsIn this study, our data showed that C10orf99 knockdown ameliorated imiquimod (IMQ)‐induced red plaques in mice and reduced the number of microvessels. Furthermore, we found such an effect was achieved by down‐regulating the expression of vascular endothelial growth factor (VEGF) and metallomatrix proteinase 2 (MMP2). Consistently, C10orf99 knockdown significantly downgraded the expression of MMP2 and VEGF in cellular model of psoriasis.ConclusionThese results suggested that C10orf99 could regulate angiogenesis in psoriasis and it might be a promising potential target of psoriasis.

Increased serum levels of proNGF, mature NGF and interleukins in burn-injured children.

Burns are among the most common injuries in children. In burns of more than 20% of the total body surface area, a systemic inflammatory response involving several chemical mediators occurs. Among them, nerve growth factor (NGF) regulates the inflammatory response related to wound healing and promotes keratinocyte proliferation and angiogenesis. The aim of our study was to investigate the physiological response to injury in children with moderate-severe burns, assaying proNGF, mature NGF (mNGF), interleukins (IL)-1β, and Il-10 serum levels. This is a prospective observational study, including twelve children hospitalized for moderate-severe burns at the Gemelli Hospital (Rome). Their laboratory features were compared to those of patients with obstructive hydrocephalus who underwent surgery. Our results showed an increase in proNGF and mNGF serum levels. In burn patients, proNGF levels increased before mNGF, and serum concentrations of both were not correlated with burn extension and depth. The most significant levels of mNGF and proNGF were reported in scalds involving the face. Serum IL-1β and IL-10 peak levels were reached with a time-course pattern similar to proNGF. Our preliminary results validate the hypothesis that serum levels of proNGF and mNGF may represent inflammatory biomarkers useful for monitoring burn patients and defining new strategies for their treatment.

GPR15LG regulates psoriasis-like inflammation by down-regulating inflammatory factors on keratinocytes.

Psoriasis is a common chronic inflammatory skin disease characterized by aberrant proliferation of keratinocytes and infiltration of immune cells. We previously found that GPR15LG protein is highly expressed in psoriasis lesional skin and it positively regulates psoriatic keratinocyte proliferation. Our data also showed that GPR15LG could regulate the activity of NF-κB pathway, which is associated with psoriatic inflammation. In the present study, we demonstrated that Gpr15lg (ortholog of GPR15LG) knockdown attenuated the severity of imiquimod (IMQ)-induced psoriasis-like inflammation in mice. Such an effect was achieved by down-regulating the expression of inflammatory cytokines interleukin (IL)-1α, IL-1β, tumor necrosis factor (TNF)-α and S100A7. Consistently, GPR15LG knockdown in vitro significantly downgraded the expression of inflammatory factors in the cellular model of psoriasis. These results suggested that GPR15LG could be involved in the development of psoriasis by regulating inflammation.

Efficacy of antioxidants in the management of psoriasis: A case control study

Introduction: Psoriasis is a chronic, immune-mediated inflammatory dermatosis. The pathophysiology of the disease is still incompletely elucidated and multiple factors are said to be involved in its initiation and perpetuation, e.g., stressors, genetic factors, environmental factors. In the last decade, a new theory is trying to explain the pathophysiology of this disease by looking at the role played by oxidative stress and chronic inflammation in the initiation of keratinocyte proliferation and differentiation. Keeping in consideration the increased oxidative stress in the patients of psoriasis, the anti-oxidant drugs can form an important part of the therapeutic ladder of psoriasis. Materials and Methods: The aim of this study was to measure the possible role of oxidative stress in psoriasis patient by measuring SOD level and comparing it with normal individuals and administer antioxidants supplements to the patients group to see the efficacy. It was a Case- Control study (1st part) and Clinical Trial without control group (2nd part). The study was carried out in Psoriasis awareness Club from June 2023 to December 2023. Purposive sampling done who fulfill the inclusion &amp; exclusion criteria. 23 patients with psoriasis and 23 age and sex matched control subjects were recruited for this study. Clinical severity of the disease was determined by PASI score. All patients and control subjects were examined for plasma SOD level. 23 psoriatic patients were given antioxidant therapy in the form of once daily tablet for 30 days. PASI score, DLQI and SOD (Superoxide dismutase) level were measured before therapy (day 0) and after therapy (day 30) in patients group. Statistical analysis and Results: Data were expressed as mean ± standard deviation (SD) for quantitative variables and numbers. For comparison of two means (t test) and (ANOVA "F") test were used for several means. Chi-square (χ2 ) or fisher exact test were used when appropriate, (P&lt;0.05) was considered statistically significant. The mean age of the patients and control subjects were 37.64 (±5.89) and 33.6 (11.02) years, respectively. The mean duration of the disease was 12.43 (±8) years. No significant difference was observed between SOD level of psoriatic patients &amp; controls. No significant correlations of SOD level with severity of psoriasis and duration of disease were found. We observed no statistically significant difference in PASI and DLQI scores before and after antioxidant therapy but there was significant increase in the level of SOD after treatment. Conclusion: It is indisputable that antioxidant supplementation can reduce the overall morbidity, enhance the prognosis of psoriasis. Notably, in most cases, antioxidants alone are not able to induce significant clinical changes in the aspect and/or course of the disease, except perhaps in mild forms. They must be used in conjunction with standard pharmacological treatments to achieve measurable results.

In Silico and In Vitro Studies on an Asymmetrical Porphyrin Derivative with Therapeutic Potential in Skin Disorders.

For developing novel photosensitizers with therapeutic potential in non-malignant and malignant cutaneous disorders, the unsymmetrical porphyrin, 5-(2-hydroxy-3-methoxyphenyl)-10, 15, 20-tris-(4-carboxymethylphenyl) porphyrin, was evaluated in silico and in vitro. The cellular uptake of the investigated porphyrin and its ability to perform photodynamic therapy were investigated in terms of the viability, proliferation, and necrosis of human HaCaT keratinocytes and human Hs27 skin fibroblasts, in correlation with the predictions regarding diffusion through cell membranes, ADMET profile (absorption, distribution, metabolism, elimination, toxicity), and potential pharmacological mechanism. Molecular docking and 250 ns molecular dynamics simulations revealed that P5.2 has the potential to form a relatively stable complex with the carbonic anhydrase IX catalytic site, the lowest predicted free energy of binding (MM/PBSA) being -39.097 kcal/mol. The results of the in vitro study showed that P5.2 is incorporated within 24 h in the investigated cells, especially in HaCaT keratinocytes, indicating its photosensitizing ability. Nevertheless, P5.2 does not exert significant cytotoxicity in "dark" conditions. In turn, PDT induced a decrease in the number of metabolically active HaCaT keratinocytes within 24 h, accompanied by a 4-fold increase in lactate dehydrogenase release, indicating its ability to perform PDT in human skin cells. The experimental results suggest that the asymmetrical porphyrin is a promising candidate theranostics agent for skin disorders.

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.

MiR-181a/b-5p negatively regulates keratinocytes proliferation by targeting MELK.

Accumulating evidence indicates that microRNAs (miRNAs) have a vital effect on the pathogenesis of psoriasis. This study is conducted to investigate the potential involvement of miR-181a-5p and miR-181b-5p in the proliferation of HaCaT keratinocytes. Cell viability and proliferation were evaluated respectively in this study using the CCK-8 and the 5-ethynyl-2'-deoxyuridine (EdU) assays. The expression of Maternal Embryonic Leucine Zipper Kinase (MELK) and Keratin 16 (KRT16) mRNA and protein in tissues and cells was assessed using quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting. The Luciferase reporter system analyzes the connection between miR-181a-5p/miR-181b-5p and MELK. The results showed that miR-181a/b-5p expression was downregulated in the psoriasis lesions and negatively regulated the proliferation of keratinocytes. MELK was directly targeted by miR-181a-5p/miR-181b-5p. In addition, HaCaT keratinocytes proliferation was inhibited by knockdown of MELK while promoted dramatically by MELK overexpression. Notably, miR-181a/b-5p mimics could attenuate the effects of MELK in keratinocytes. In conclusion, our research findings suggested miR-181a-5p and miR-181b-5p negatively regulate keratinocyte proliferation by targeting MELK, providing potential diagnostic biomarkers and therapeutic targets for psoriasis.

Multiple cutaneous squamous cell carcinoma of the forehead in a patient with skin of color treated by wide local excision with adjuvant radiotherapy: a case report

Cutaneous squamous cell carcinoma is the second most common non-melanoma skin cancer, characterized by the proliferation of keratinocytes, with an increasing incidence worldwide. In cases of perineural invasion, surgical excision followed by adjuvant radiotherapy is the preferred treatment. An intraoperative frozen section is necessary to determine the cancer-cell-free margin. A 80-year-old male presented to the outpatient department of our hospital with two fungating growths over his right forehead (size 2.7×1.2 cm) and right temple region (size 4×1.2 cm) for 5 years. An incisional biopsy of the growths revealed well-differentiated squamous cell carcinoma. There was no evidence of lymphadenopathy. The patient was treated successfully by wide local excision of the growths with an intraoperative frozen section to determine negative margins. Local defects of the forehead and right temple were reconstructed with a scalp rotation flap and a split skin thickness graft, respectively. The final histopathological examination showed moderately differentiated squamous cell carcinoma with resection-free margins. Forehead growth showed perineural invasion. The patient underwent 30 fractions of image-guided adjuvant radiotherapy in view of perineural invasion and to avoid local recurrence. The patient recovered well without any recurrences or complications. Surgical excision and reconstruction followed by adjuvant radiotherapy is the most effective method for treating cutaneous squamous cell carcinomas with perineural or lymphovascular invasion. Intraoperative frozen section is necessary to reduce recurrence rates and metastasis. Ours is a rare case of multiple cutaneous squamous cell carcinomas involving the forehead region.

WTAP mediated m6A-modified circ_0056856 contributes to the proliferation, migration, and invasion of IL-22-stimulated human keratinocyte by miR-197-3p/CDK1 axis.

Psoriasis is a chronic inflammation-associated skin disorder, and interleukin-22 (IL-22) is involved in psoriasis pathogenesis by boosting the proliferation and migration of keratinocytes. Mounting evidence has shown that circRNAs might play an important role in several aspects of psoriasis. This study is designed to explore the role and mechanism of circ_0056856 in regulating the phenotypes of IL-22-induced keratinocytes (HaCaT cells). Circ_0056856, microRNA-197-3p (miR-197-3p), Cyclin-dependent kinase 1 (CDK1), and Wilms tumor 1-associated protein (WTAP) levels were detected using real-time quantitative polymerase chain reaction (RT-qPCR). Cell viability, proliferation, migration, and invasion were analyzed using 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT), 5-ethynyl-2'-deoxyuridine (EdU), Wound scratch, and Transwell assays. After being predicted by Circinteractome or TargetScan, binding between miR-197-3p and circ_0056856 or CDK1 was verified by a dual-luciferase reporter assay. CDK1 and WTAP protein levels were determined using Western blot. Interaction between WTAP and circ_0056856 was assessed using methylated RNA immunoprecipitation (MeRIP) assay. Increased circ_0056856, CDK1, and WTAP were observed in psoriasis patients and IL-22-treated HaCaT cells. Moreover, circ_0056856 knockdown might repress IL-22-induced HaCaT cell proliferation, migration, and invasion in vitro. In mechanism, circ_0056856 might function as a sponge of miR-197-3p to modulate CDK1 expression, and WTAP improved circ_0056856 expression via m6A methylation. WTAP-guided m6A modified circ_0056856 facilitates IL-22-stimulated HaCaT cell damage through the miR-197-3p/CDK1 axis, which could provide novel insights into psoriasis treatment.