Effect of opioid receptor antagonist on mitigating tumor necrosis factor-like weak inducer of apoptosis (TWEAK)-induced apoptolysis in pemphigus pathogenesis.

Pemphigus is a severe autoimmune blistering disease characterized by acantholysis triggered by autoantibodies against desmoglein 1 and 3 (DSG1/3). Apoptosis plays a pivotal role in facilitating acantholysis, yet the precise underlying mechanism remains obscure. Tumor necrosis factor-like weak inducer of apoptosis (TWEAK) is known to promote apoptosis and disrupt cell junctions, although its involvement in pemphigus pathogenesis remains ambiguous. Our study observed decreased DSG1/3 expression alongside increased TWEAK/fibroblast growth factor-inducible 14 (Fn14) expression and keratinocyte apoptosis in both lesional and perilesional skin. In vitro experiments revealed that TWEAK-stimulated keratinocytes exhibited enhanced apoptosis, STAT1 phosphorylation, and reduced intercellular DSG1/3 expression. Notably, bulk-RNA sequencing unveiled that CASPASE-3 was responsible for mediating the DSG1/3 depletion, as confirmed by direct interaction with DSG1/3 in a co-immunoprecipitation assay. Naloxone, known for preserving cellular adhesion and preventing cell death, effectively reduced apoptosis and restored DSG1/3 levels in TWEAK-stimulated keratinocytes. The anti-apoptotic properties of naloxone were further validated in a murine pemphigus model. Our findings elucidate that TWEAK facilitates keratinocyte apoptosis by augmenting caspase-3 activity, leading to DSG1/3 depletion and apoptosis in pemphigus. Importantly, naloxone can counter TWEAK-induced apoptosis in pemphigus pathogenesis, offering a potential therapeutic intervention.

Hypoxia-Induced Ephrin-B2 Facilitates Proliferation and Induces Glycolytic Metabolism in Cutaneous Squamous Cell Carcinoma by Modulating PKM2/HIF-1α Axis.

BACKGROUND: Cutaneous squamous cell carcinoma (cSCC) is a fatal disease characterized by metabolic dysregulation. The role of ephrin type-B receptor 2 (ephrin-B2), a crucial molecule in cancer cell biology, in regulating glycolysis and cell proliferation of cSCC is not well understood. This study aimed to investigate the biological pathways by which ephrin-B2 impacts the glycolysis and cell proliferation of cSCC. METHODS: Ephrin-B2 expression levels in cSCC were determined using quantitative reverse-transcription polymerase chain reaction (qRT-PCR) and Western blotting. Ephrin-B2 expression in cSCC cells was manipulated using overexpression and knockdown approaches. A series of in vitro assays, such as cell counting kit-8 (CCK-8), Transwell assay, immunofluorescence assay, enzyme-linked immunosorbent assay (ELISA), qRT-PCR, and Western blotting, were employed to delineate the biological roles of ephrin-B2/pyruvate kinase muscle isoenzyme 2 (PKM2)/hypoxia-inducible factor 1 alpha (HIF-1α) in proliferation, migration, invasion, and glucose metabolism of cSCC. RESULTS: This study highlights an upregulation of ephrin-B2 expression in cSCC. Knockdown of ephrin-B2 significantly suppressed the proliferation, migration, invasion, and glucose metabolism of cSCC cells. Moreover, ephrin-B2 expression was upregulated under hypoxic conditions. At the molecular level, ephrin-B2 knockdown resulted in the downregulation of PKM2 and HIF-1α expression. Additionally, the overexpression of PKM2 or HIF-1α successfully rescued the diminished proliferation, migration, invasion and glucose metabolism induced by ephrin-B2 knockdown in cSCC cells. CONCLUSION: These findings suggest that ephrin-B2 suppression may hinder cSCC cell proliferation and glycolytic metabolism, potentially via the PKM2/HIF-1α axis modulation.

Interferon-Alpha Induces Psoriatic Inflammation in Mice by Phosphorylating FOXO3.

Psoriasis is a chronic, immune-mediated inflammatory skin disease characterized by epidermal thickening and inflammatory cell infiltration. Excessive proliferation of keratinocytes and resistance to apoptosis lead to thickening of the epidermis. Plasmacytoid dendritic cells are involved in the occurrence of psoriasis mainly by secreting interferon-alpha (IFN-α). IFN-α is a glycoprotein with antiviral, antitumor, and immunomodulatory effects, but its role in psoriasis remains unclear. In this investigation, a mild psoriatic phenotype was observed in mice upon topical application of IFN-α cream, and the inflammation was exacerbated when combined with imiquimod (IMQ). Immunohistochemical analyses demonstrated that IFN-α induces psoriatic inflammation in mice by stimulating phosphorylation of forkhead box O3, consistent with the involvement of this protein in cell proliferation, apoptosis, and inflammation. Our results suggested that topical IFN-α caused psoriatic inflammation and that the psoriatic inflammation was exacerbated by the combination of IFN-α and IMQ, possibly due to the dysfunction of forkhead box O3.

Efficacy and safety of low-dose oral isotretinoin monotherapy versus combined therapy with picosecond laser for the treatment of acne scars in Asian population.

PURPOSE: Acne scars are common in patients with moderate to severe acne. Isotretinoin is the first-line treatment for those patients, but whether oral isotretinoin can improve acne scar is not clear. Picosecond lasers (FxPico) has been reported to improve acne scars. In the present study, we evaluated the clinical efficacy of low-dose isotretinoin with or without FxPico treatment for acne scars. MATERIALS AND METHODS: A total of 48 patients with acne scars were enrolled and were randomly assigned to receive low dose oral isotretinoin or not. For all the patients in both treatment groups, one side of face were randomly assigned to be treated with picosecond laser. Assessments, including photos, échelle d'évaluation clinique des cicatrices d'acné (ECCA) and Global Acne Grading System (GAGS) score, the number of lesions, melanin and erythema indexes, transepidermal water loss were assessed at 0, 1, 2, and 3 month. Side effects, Dermatology Life Quality Index (DLQI) and satisfaction were recorded before and after the study. RESULTS: A total of 44 patients completed the study (24 received oral low dose isotretinoin and 20 did not). Low dose oral isotretinoin treated group showed significant improvement on ECCA (from 112.5 [50-180] to 105 [50-160]), GAGS score (from 12.6 ± 3.3 to 10.1 ± 3.0), the count of papules (from 4.3 ± 3.7 to 1.0 ± 1.5) than the blank group, and higher improvement were noticed after isotretinoin combined with FxPico. All the side effects were temporary and tolerable, no adverse effects were observed. Higher DLQI and patients' satisfaction were achieved by oral isotretinoin alone and isotretinoin combined with FxPico. CONCLUSIONS: This is the first paper showing the improvement of scars by early low dose-isotretinoin intervention with or without the combination of picosecond laser. Early intervention with oral low-dose isotretinoin is effective for the treatment and prevention of acne scars, the combined therapy with FxPico can achieve better outcome.

Conjugation of the Fn14 Ligand to a SMAC Mimetic Selectively Suppresses Experimental Squamous Cell Carcinoma in Mice.

The mimetic of SMAC induced cell death in cancers by depleting the inhibitor of apoptosis proteins. Recent studies showed that Fn14 is overexpressed in the cells of squamous cell carcinoma (SCC), providing a promising candidate target for selective antitumor therapy. In this study, we conjugated a small-molecule SMAC mimetic MV1 to the ligand of Fn14, TWEAK. Our results showed that TWEAK‒MV1 conjugate retained adequate binding specificity to Fn14-positive SCC cells in vitro and accumulated selectively in tumor tissue of cutaneous SCC xenografts mice after intraperitoneal administration. This conjugation compound exhibited remarkable effectiveness in suppressing tumor growth and extending overall survival without causing significant side effects in SCC xenograft mice. Moreover, TWEAK‒MV1 conjugate greatly enhanced both apoptotic and necroptotic cell death both in vitro and in vivo, accompanied by a cellular inhibitor of apoptosis proteins degradation as well as activation of receptor-interacting protein kinase. Taken together, our preclinical data suggested that the designed conjugation compound of TWEAK and MV1 might provide a potential therapeutic strategy for cutaneous SCC with improved antitumor efficacy and negligible toxicity.

TWEAK Promotes the Proliferation of Squamous Cell Carcinoma Cells Through Activating cIAP1 Signals.

Recent studies showed that tumor necrosis factor (TNF)-like weak inducer of apoptosis (TWEAK) induces the proliferation of squamous cell carcinoma (SCC) cells. However, the precise mechanism underlying such effect of TWEAK remains unclear. This study was designed to elucidate the role of cellular inhibitor of apoptosis 1 (cIAP1) in TWEAK-induced proliferation of SCC cells. Human SCC cells (SCC-13, A431, and SCC-9) were cultured in vitro, receiving the stimulation of TWEAK or TNF-related apoptosis-inducing ligand (TRAIL). We found that TWEAK induced cytoplasmic cIAP1 importation and RIP1 ubiquitination in cells, followed by the activation of canonical nuclear factor kappa B signals. MV1, a cIAP1 inhibitor, abrogated TWEAK-induced proliferation of these cells. Moreover, the interaction between TWEAK and its receptor, fibroblast growth factor-inducible 14 (Fn14), enhanced the expression of TRAIL receptor types 3 and 4 (TRAIL-R3/4). Furthermore, the transfection of TRAIL-R3/4 siRNA abrogated the promotion effect of TWEAK on SCC-13 cell proliferation and cIAP1 expression. Therefore, TWEAK/Fn14 interaction promotes the proliferation of SCC cells through activating cIAP1 signals. Targeting the downstream cIAP1 signals might attenuate the effect of TWEAK on SCC cells.

Tumor Necrosis Factor (TNF) Receptor Expression Determines Keratinocyte Fate upon Stimulation with TNF-Like Weak Inducer of Apoptosis.

The interaction between tumor necrosis factor- (TNF-) like weak inducer of apoptosis (TWEAK) and fibroblast growth factor-inducible 14 (Fn14) regulates the fate of keratinocytes, depending on the relative expression of TNF receptor (TNFR) 1 or TNFR2. However, the precise mechanism underlying this TWEAK-mediated regulation remains unclear. The aim of this study was to provide comprehensive insight into the roles of Fn14, TNFR1/2, and other relevant molecules in the fate of keratinocytes. Further, we sought to elucidate the structural basis for the interaction of TWEAK and Fn14 in regulating cellular outcomes. Normal keratinocytes (mainly expressing TNFR1) and TNFR2-overexpressing keratinocytes were stimulated with TWEAK. Through immunoprecipitation and Western blotting of keratinocyte lysates, we elucidated the associations between Fn14, TNFR-associated factor 2 (TRAF2), cellular inhibitor of apoptosis protein 1 (cIAP1), and TNFR1/2 molecules. Additionally, we found that TRAF2 exhibited binding to Fn14, cIAP1, and TNFR1/2. Our data suggest that TWEAK induces apoptosis in normal keratinocytes and proliferation in TNFR2-overexpressing keratinocytes in a TNF-α-independent manner; however, inhibition of TRAF2 appears to reverse this effect. Interestingly, the interaction between TWEAK and Fn14 increased TNFR1-associated death domain protein and caspase-8 expression in normal keratinocytes and promoted cytoplasmic import of cIAP1 in TNFR2-overexpressing keratinocytes. In conclusion, we found that the Fn14-TRAF2-TNFR signaling axis mediates TWEAK's regulation of the fate of keratinocytes, possibly in a manner involving the TNF-α-independent TNFR signal transduction.

CDC20 contributes to the development of human cutaneous squamous cell carcinoma through the Wnt/ß­catenin signaling pathway.

Cell division cycle 20 (CDC20) is a regulatory molecule and serves critical roles at multiple points of the cell cycle. Recent evidence indicates that CDC20 may serve an oncogenic role in a number of human cancer types. However, the role of CDC20 in primary cutaneous squamous cell carcinoma (cSCC) has not been studied, to the best of our knowledge. The aim of the present study was to investigate whether and how CDC20 is involved in the tumorigenesis of cSCC. The results revealed that CDC20 expression was significantly increased in cSCC tissues and cell lines, and its expression was associated with pathological differentiation. Downregulation of CDC20 inhibited cell proliferation, induced cell cycle arrest, promoted apoptosis and reduced migratory ability through inhibition of the Wnt/ß­catenin signaling pathway. Furthermore, all­trans­retinoic acid treatment significantly downregulated CDC20 expression in cSCC. The present results revealed that CDC20 may serve a crucial role in human cSCC, and suggested that CDC20 may be a novel biomarker for the prevention, diagnosis and treatment of cSCC.

TWEAK/Fn14 Interaction Confers Aggressive Properties to Cutaneous Squamous Cell Carcinoma.

Recent studies showed that TWEAK/Fn14 signaling participates in the progression of internal malignancies. However, its role in the biological properties of cutaneous squamous cell carcinoma (SCC) remains unclear. This study was designed to explore the effect of TWEAK/Fn14 activation on cutaneous SCC as well as the relevant mechanism. The expression of TWEAK and Fn14 was determined in tissue samples of patients with cutaneous SCC. Human primary keratinocytes and SCC cell lines were cultured in vitro, receiving stimulation of TWEAK. The xenografts of SCC were generated subcutaneously in BALB/c nude mice. The results showed that both TWEAK and Fn14 were highly expressed in human cutaneous SCC. Moreover, TWEAK/Fn14 activation promoted the proliferation, migration, and invasion of cultured SCC cells. Interestingly, TNFR2 was upregulated in cultured SCC cells, and the transfection of TNFR2 small interfering RNA abrogated the effect of TWEAK on these cells. Finally, the favorable effect of TWEAK/Fn14 signals was confirmed in BALB/c nude mice with SCC xenografts. In conclusion, TWEAK/Fn14 signals contribute to the progression of cutaneous SCC, possibly involving the TNF-α-independent TNFR2 signal transduction.

Concomitant Use of 1,550-nm Nonablative Fractional Laser With Low-Dose Isotretinoin for the Treatment of Acne Vulgaris in Asian Patients: A Randomized Split-Face Controlled Study.

BACKGROUND: Nonablative fractional laser (NAFL) has been shown to improve the appearance of inflammatory acne and acne scars. Isotretinoin is effective for the treatment of moderate-to-severe cases of recalcitrant acne. However, the recommended dose of isotretinoin can have profound effects. OBJECTIVE: To investigate the clinical efficacy and safety of performing NAFL treatment in patients with moderate-to-severe acne vulgaris under treatment with low-dose oral isotretinoin. METHODS AND MATERIALS: Eighteen patients who received 10-mg oral isotretinoin per day completed 3 sessions of NAFL treatment on one half of the face and presented for each scheduled follow-up appointment. RESULTS: Low-dose isotretinoin was effective in managing papules and nodule lesions (p < .001). Comedo lesions were significantly improved on NAFL-treated half-faces, compared with untreated half-faces (p < .05) as well as on the appearance of atrophic boxcar scars (superficial boxcar scar, p < .05; deep boxcar scar, p < .01). The most common side effects of oral isotretinoin were xerostomia and cheilitis. The most common discomforts associated with NAFL treatment were mild transient erythema and edema in the treated area. CONCLUSION: The combination of NAFL with low-dose isotretinoin is a safe and effective treatment for moderate-to-severe acne.

TWEAK/Fn14 signaling in tumors.

TWEAK (tumor necrosis factor-related weak inducer of apoptosis), a member of the tumor necrosis factor superfamily, acts on cells by binding to its only receptor named Fn14 (fibroblast growth factor-inducible 14). Their engagement activates a number of intracellular signal transduction cascades and consequently leads to cell death, proliferation, migration, or survival depending on the cellular contexts. Studies have indicated that the expression of TWEAK and Fn14 is upregulated in many solid tumors compared with healthy tissues. The activation of TWEAK/Fn14 signaling enhances the proliferation, invasion, and migration of tumor cells. Moreover, the angiogenesis, pro-inflammatory cytokine expression, and epithelial-mesenchymal transitions are promoted upon TWEAK/Fn14 activation. Currently, the tumor necrosis factor receptor-associated factor and nuclear factor kappa B signaling pathways are considered two main downstream pathways activated by TWEAK/Fn14 interaction. In view of these facts, some TWEAK- or Fn14-targeting agents are generated to inhibit the progression of tumors and have achieved initial success in clinical and pre-clinical trials. These agents include monoclonal antibodies, fusion proteins, immunotoxins, and nanoparticles. In addition, some relevant signaling pathways are studied to identify new potential therapeutic targets. Overall, these findings suggest that the TWEAK/Fn14 pathway is critical in the development of tumors, and targeting this signaling is a potential therapeutic approach in future tumor therapy.

The long-term effect of 1550 nm erbium:glass fractional laser in acne vulgaris.

We evaluated the short-term and long-term effects of the 1550 nm erbium:glass (Er:glass) fractional laser in the treatment of facial acne vulgaris. Forty-five (9 male and 36 female) acne patients were treated 4 times at 4-week intervals with the following parameters: 169 spot density and 15-30 mJ/cm(2) fluence. There was no control group. The laser spots were adjustable (maximum overlap: 20%) according to the treatment area, and delivered in rows in order to cover all the face. Clinical photographs were taken. The IGA scores and lesion counts were performed for each treatment. Their current state was obtained by phone call follow-up to determine the long-term effect and photographs were offered by themselves or taken in hospital. After four treatments, all patients had an obvious reduction of lesion counts and IGA score and the peak lesion counts decreased to 67.7% after the initial four treatment sessions. For long-term effect, 8 patients lost follow-up, hence 37 patients were followed-up. 8 patients were 2-year follow up, 27 at the 1-year follow-up, and all patients at the half-year follow-up. The mean percent reduction was 72% at the half-year follow-up, 79 at the 1-year follow-up and 75% at the 2-year follow-up. Side effects and complications were limited to transient erythema and edema, and few patients suffered from transient acne flare-ups and sensitivity. All patients responded that their skin was less prone to oiliness. In conclusion, acne can be successfully treated by 1550 nm Er:glass fractional laser, with few side effects and prolonged acne clearing.