Experimental Dermatology

Abstract Background: Immune-mediated skin diseases frequently co-occur, but the molecular architecture connecting clinically distinct disorders, and the extent to which molecular proximity predicts shared therapeutic opportunity, remain incompletely defined. We constructed a multilayer skin diseasome integrating transcriptomic overlap, pathway enrichment, protein-interactome topology, curated disease associations, real-world clinical co-occurrence, and drug-perturbation signatures across psoriasis (PS), atopic dermatitis (AD), hidradenitis suppurativa (HS), vitiligo (VL), and chronic spontaneous urticaria (CSU), using sodium lauryl sulfate-induced irritant contact dermatitis (SLS-ICD) as a mechanistically distinct barrier-injury comparator. Methods: Differentially expressed genes (DEGs) were derived from publicly available NCBI Gene Expression Omnibus datasets and compared using exclusive pairwise and higher-order intersections. Gene Ontology biological-process enrichment characterized shared and condition-specific programs. Interactome-based network separation (S_AB) quantified the relative topological proximity of disease modules. DisGeNET enrichment generated candidate disease +associations, a selected subset of which was examined descriptively for patient co-occurrence in TriNetX. Candidate compounds were ranked by reversal of disease-associated expression signatures against LINCS L1000 perturbation profiles. Results: The largest exclusive DEG intersection occurred between PS and HS (2,060 genes), followed by AD-PS-HS (490), VL-PS (464), AD-PS (402), and VL-PS-HS (379). Fourteen genes were shared across PS, AD, HS, VL, and CSU but not SLS-ICD. Neutrophil-associated processes recurred across the immune-mediated conditions, whereas SLS-ICD was dominated by keratinization and epidermal-differentiation programs. PS and HS had the lowest observed network-separation value (S_AB = -0.594); SLS-ICD had positive S_AB values in all five comparisons, although this separation did not persist once module sizes were harmonized. DisGeNET linked the index conditions to diverse immune, cardiovascular, neurologic, and neoplastic categories; 42 of these candidate diseases were observed to co-occur with an index condition in the queried TriNetX cohorts. Drug-signature overlap was greatest between PS and CSU, despite their marginal interactome separation, indicating that interactome proximity and predicted pharmacologic reversal capture different dimensions of disease relatedness. mTOR/PI3K-pathway inhibitors were prominent among the psoriasis reversal candidates, while methotrexate and mycophenolate mofetil emerged from both the CSU signature and the curated gene set associated with HIV infection. Conclusion: Multilayer integration identified a connected molecular core among five immune-mediated skin diseases and a distinct SLS-ICD injury module. The discordance between interactome proximity and drug-signature overlap suggests that no single layer adequately defines disease relatedness. These findings provide a hypothesis-generating framework for prioritizing disease links and repurposing candidates, but controlled epidemiologic analyses and experimental validation are required before clinical or therapeutic inference.

Pannexin 1 (PANX1) is a channel-forming glycoprotein that has been implicated in regulating melanoma cell properties such as growth, migration, and invasion. Here we report that the CRISPR-Cas9 mediated ablation of PANX1 or channel inhibition with probenecid shifted A375-P cell cycle distribution towards G2/M, while channel inhibition with spironolactone stalled cell cycle progression at the G1/S checkpoint regardless of PANX1 expression. Bulk RNA sequencing revealed cell cycle related gene expression was downregulated with PANX1 targeting strategies and this was exacerbated when PANX1 deficient cells were treated with spironolactone. When grown as spheroids, we found the deletion and inhibition of PANX1 disrupted spheroid compaction, with spheroids displaying poorly defined borders and reduced circularity. The deletion of PANX1 increased spheroid fragmentation, and this phenotype was intensified when spheroids devoid of PANX1 were treated with spironolactone, highlighting a potential synthetic lethal effect. Using liquid chromatography mass spectrometry, we sought to determine whether PANX1 had binding partners that may act to stabilize spheroid integrity and found that PANX1 co-immunoprecipitated various cell adhesion molecules such as {beta}-actin and F-actin-capping protein subunit -1, suggesting PANX1 and its interacting partners may stabilize cell-cell contacts. When control and PANX1 ablated cells were grown in chick chorioallantoic membrane xenografts to assess their tumour growth characteristics, we discovered that the deletion of PANX1 reduced tumour surface area and viability. Our findings indicate that PANX1 regulates cell cycle progression and the structural architecture of A375-P melanoma tumours, highlighting the therapeutic utility of targeting PANX1 in melanoma.

Hypothyroidism has been associated with increased skin cancer risk, whereas greater genetic susceptibility to hypothyroidism is associated with lower risk. These opposing associations suggest that the average risk associated with hypothyroidism may conceal substantial heterogeneity among patients, and that genetic background could help identify those at highest risk. In this study, we analyzed more than 650,000 individuals across All of Us and FinnGen cohorts to determine whether a hypothyroidism polygenic risk score (H-PRS) stratifies skin cancer risk among patients with autoimmune hypothyroidism and whether integration of a skin cancer polygenic risk score (SC-PRS) further refines risk. In FinnGen, autoimmune hypothyroidism was associated with increased skin cancer hazard (hazard ratio [HR] = 1.10; 95% CI [1.06, 1.15]), whereas H-PRS was inversely associated with risk (HR=0.97 per 1-SD increase; 95% CI [0.95, 0.98]). The hypothyroidism x H-PRS interaction was also negative (HR=0.94; 95% CI [0.91, 0.98]), indicating greater hypothyroidism-associated risk at lower H-PRS. The hypothyroidism and H-PRS associations replicated in All of Us, and similar H-PRS risk gradients were observed for melanoma, basal cell carcinoma, and squamous cell carcinoma in both cohorts. Among hypothyroid patients, predicted 10-year risk increased with higher SC-PRS and lower H-PRS. Combined clinical-genetic profiles had HRs ranging from 2.32 at the 20th H-PRS/80th SC-PRS percentiles to 3.37 at the 5th/95th percentiles, exceeding published point estimates for the established dermatological risk factors. Among women aged 55, representing the more commonly affected sex at approximately the median age of diagnosis, 10-year risk of skin cancer was 14.9% (95% CI [8.4%, 20.9%]) in the highest-SC-PRS/lowest-H-PRS quartiles versus 2.8% (95% CI [1.0%, 4.7%]) in the opposite quartiles. Overall, these findings support PRS-guided risk stratification for targeted skin cancer prevention and surveillance.

Aging is associated with impaired skin wound healing, but the molecular mechanisms underlying this decline remain incompletely understood. In particular, how aging affects the temporal regulation of mechanosensitive signaling during tissue repair is poorly understood. In this study, we investigated age-associated changes in cutaneous wound healing, with a focus on Yes-associated protein (YAP)-associated mechanosensitive responses, and examined whether ICE mice, an inducible model of epigenetic aging, reproduce age-associated impairment in wound repair. Splinted full-thickness excisional wounds were generated in young and naturally aged mice, and wound closure, gene expression, and active YAP were evaluated over time. Aged mice exhibited delayed wound closure, particularly during the mid-to-late phases of repair. Expression of the fibrosis-related genes Tgfb1, Col1a1, and Col3a1, and the YAP-associated genes Ctgf, Cyr61, and Arhgap18 did not differ significantly between young and aged wounds at the examined time points. In contrast, Ankrd1 was selectively elevated in aged wounds at postoperative day 14. Active YAP immunofluorescence showed age-associated differences in staining patterns during wound healing, indicating altered regulation of mechanosensitive signaling with aging. Furthermore, ICE mice exhibited delayed wound closure compared with Cre control mice, reproducing a major functional feature observed in naturally aged mice. These findings suggest that age-associated impairment of wound healing is characterized not by uniform activation or suppression of YAP-related signaling, but by altered temporal regulation of mechanosensitive responses together with selective Ankrd1 elevation. ICE mice could provide a useful experimental model for investigating age-associated defects in cutaneous wound healing.

Nurse-led skin cancer screening extends specialist reach but depends on the nurse selecting which lesions to forward for diagnosis, and performance varies with experience. We evaluated whether real-time decision support using artificial intelligence (AI) improves malignancy detection in routine nurse-led teledermoscopy screening across MoleMap clinics in New Zealand and Australia (January 2024-July 2025). In this real-world study, clinics using AI decision support were compared with standard clinics. Nurses examined patients, captured dermoscopic images, and forwarded selected lesions to teledermatologists, who provided the reference diagnosis. The analytic cohort comprised 1,102,382 lesions from 98,422 patients across 577 sites. AI-assisted screening was associated with a higher malignancy detection rate than standard screening (25.5 vs 15.7 malignancies per 1,000 lesions; odds ratio adjusted for nurse experience 1.73, 95% CI 1.68-1.77), a finding consistent across all nurse-experience tiers and the three major malignant subtypes. AI assistance was also associated with a shift in recommended management: 21 additional intervention recommendations and 13 additional safety-netting recommendations (self-monitoring, short-term follow-up, or specialist referral) per 1,000 lesions, approximately balanced by 34 fewer no-action recommendations. The reference standard was teledermatologist diagnosis and allocation was not randomised; findings are therefore associational and require prospective, outcome-based confirmation.

Background Vitiligo is an acquired depigmenting disorder characterised by melanocyte loss. While immune responses against melanocytes are implicated in its pathogenesis, melanocyte detachment, melanocyte senescence and aberrant epidermal differentiation are increasingly characterised as additional pathological features. Granzyme B (GzmB), classically recognised as an intracellular effector of perforin-dependent cytotoxicity, is increased in vitiligo lesions; however, its extracellular contribution to vitiligo pathology remains unclear. Objectives To determine whether extracellular GzmB contributes to depigmentation and epidermal pathological features relevant to vitiligo, and to define its cellular source and underlying mechanisms. Methods Human vitiligo skin samples, murine depigmentation models and cultured human epidermal cells were analysed. The functional effects of extracellular GzmB were examined by subcutaneous administration of recombinant GzmB in mice. A rhododendrol (RD)-induced leukoderma model was used to evaluate the disease relevance of GzmB and the therapeutic effect of topical GzmB inhibition with VTI-1002. Results GzmB-positive cells were markedly increased in active vitiligo lesions and were predominantly associated with tryptase-positive cells, with limited co-distribution with CD8 or perforin. Vitiligo lesions also showed melanocyte detachment, increased p16INK4A-positive melanocytes and aberrant keratinocyte differentiation. These pathological features were recapitulated in vivo by extracellular GzmB administration, accompanied by focal depigmentation. In cultured melanocytes, GzmB exerted no cytotoxic effects but reduced attachment strength and induced a senescence-associated phenotype characterised by decreased extracellular matrix- and adhesion-related gene expression, increased p16INK4A level, elevated senescence-associated {beta}-galactosidase activity and activation of transforming growth factor-{beta}/SMAD signalling. In keratinocytes, extracellular GzmB promoted aberrant differentiation associated with activation of p53 signalling. Topical inhibition of GzmB in RD-induced leukoderma attenuated depigmentation progression, melanocyte detachment, melanocyte senescence and abnormal epidermal differentiation. Conclusions Extracellular GzmB promotes depigmentation associated with inducing melanocyte detachment, melanocyte senescence and aberrant keratinocyte differentiation. These findings identify extracellular GzmB as a previously underrecognised pathogenic mediator and potential therapeutic target in vitiligo-associated depigmentation.

Purpose: Uveal melanoma (UM) is a rare but aggressive intraocular malignancy originating in the uvea (choroid, iris, and ciliary body). Despite primary treatment, 50% of UM patients develop metastases to the liver, lungs, bones, and skin. Topotecan, a topoisomerase I inhibitor, and SP141, an MDM2 inhibitor, have been studied in cancers, including retinoblastoma. This study explores a combined approach with these drugs in the 92-1 UM cell line. Methods: Primary choroidal melanoma-derived 92-1 cells were treated with topotecan and SP141 individually to determine IC50 values. Cell viability and proliferation were assessed using the MTT assay and the xCELLigence real-time monitoring system. The synergistic effects were analyzed quantitatively using the Loewe Additivity and Highest Single-Agent (HSA) models. Flow cytometry was employed to analyze cell cycle distribution, while cell death and apoptosis were monitored via high-throughput, real-time quantitative analysis using the IncuCyte live-cell kinetic imaging system. Results: Both Topotecan and SP141 induced significant cell death in 92-1 cells. xCELLigence showed dose- and time-dependent inhibition of proliferation. Combining sub-IC50 concentrations of topotecan and SP141 exhibited significant synergistic effects, markedly reducing growth. Cell cycle analysis revealed that topotecan causes a dose-dependent biphasic arrest in G2 and S phases, while SP141 causes G2/M arrest, leading to cell death. Cytotoxicity assays corroborated increased cell death following combination therapy, and the Caspase 3/7 assay indicated that apoptosis is the mechanism underlying cell death. Conclusions: The multi-targeted approach combining topotecan and SP141 drugs demonstrated synergistic therapeutic effects in 92-1 cells, suggesting a potential treatment strategy for managing UM.

Validated biomarkers for identifying patients with early-stage melanomas at high risk of metastasis are limited. We have previously shown that loss of Activating Molecule in Beclin-1-Regulated Autophagy (AMBRA1) and loricrin in the epidermal microenvironment is associated with tumour recurrence. Here we show that endothelial AMBRA1 deficiency contributes to vascular dysfunction and melanoma progression. Melanoma-conditioned media or exposure to TGF{beta}1-3 ligands induced post-transcriptional loss of AMBRA1 in endothelial cells. Transcriptomic profiling in both in vitro and human melanoma single-cell RNA sequencing datasets showed activation of cell-cycle and metabolic programmes alongside suppression of endothelial junction, adhesion and immune-supportive pathways in AMBRA1-deficient endothelial cells. Functionally, AMBRA1 loss increased endothelial cell proliferation, accelerated early tubulogenesis, impaired three-dimensional spheroid adhesion, stabilised endothelial-to-mesenchymal transition-associated transcription factors Slug and Snail, and reduced Claudin-5, VE-cadherin and N-cadherin, indicative of endothelial plasticity and dysfunction. Furthermore, loss of AMBRA1 in a subset of intratumoural and peritumoural blood and lymphatic vessels correlated significantly with metastatic progression in a cohort of 121 non-ulcerated primary AJCC stage I/II melanomas classified as AMBLor at-risk. Collectively, these findings position endothelial AMBRA1 as a regulator of vascular plasticity, dysfunction, and immune-supportive endothelial function in early-stage melanomas, and a marker of a permissive microenvironment associated with metastasis.

Purpose: The neural retina and retinal pigment epithelium/choroid (RPE/Cho) are metabolically coupled. Metabolic dysfunction of the RPE/Cho contributes to photoreceptor death in age-related macular degeneration (AMD). This study aimed to determine how aging, a major risk factor for AMD, alters the proteome and metabolic pathways in the retina and RPE/Cho. Methods: We performed quantitative proteomics on neural retina and RPE/Cho from young (8-week) and old (73-week) C57BL/6J mice. The differentially expressed proteins between old and young, as well as between the retina and RPE/Cho, were visualized using volcano plots and heatmaps, and functional analyses were assessed by Gene Ontology enrichment tools. Results: Aging altered the expression of 85 retinal proteins and 272 RPE/Cho, with 16 shared between tissues. In the aged retina, proteins associated with NADP(H) metabolism, neurodegeneration, and immunity were mostly upregulated, while proteins in lipid metabolism, transcription, and epigenetic regulation decreased. In the aged RPE/Cho, all 21 significantly altered lysosomal enzymes and transport proteins increased, together with complement components, and photoreceptor outer segment proteins. These changes accompanied increases in proteins associated with lipid metabolism and protection against lipid peroxidation, while several glutathione metabolism enzymes decreased. Seven shared proteins involved in lipid and NADP(H) metabolism, changed in opposite directions between retina and RPE/Cho. Comparison of the retinal and RPE/Cho proteomes identified 3073 differentially abundant proteins, of which 2452 maintained tissue-specific differences across both age groups, while approximately 17% showed age-dependent shifts in tissue enrichment. These shifts involved proteins associated with metabolism, extracellular matrix, visual function, lysosomal pathways, and innate immunity. Within the metabolic proteome, several glycolytic and fatty acid oxidation proteins showed greater relative enrichment in RPE/Cho with age, whereas glucose transporters and mitochondrial complexes shifted toward the retina. Conclusions: Overall, these findings show that aging differentially remodels the retina and RPE/Cho proteome, accompanied by altered metabolic specialization between the two tissues.

Purpose: Age is the leading factor for age-related macular degeneration (AMD), in which retinal pigmented epithelium (RPE) atrophy is a hallmark. The nuclear factor-erythroid 2-related factor 2 (Nrf2), a major anti-stress transcription factor, decreases in AMD, suggesting bioenergetic stress interacts with age during AMD pathogenesis. We profiled visual function and gene expression of the retina and RPE-choroid with Nrf2 deletion and aging. Methods: We tested 3mo and 14mo Nrf2 null (Nrf2 KO) and Nrf2 WT mice for optokinetic tracking (OKT) and dark-adapted electroretinography (ERG) responses. Eyes were harvested for retina outer nuclear layer (ONL) thickness analysis and retina and RPE-choroid cup RNA isolation for RNAseq profiling. Results: Visual acuity was reduced with aging with lower values in the Nrf2 KO vs Nrf2 WT comparison at 14mo. We observed aged-related reduction of a-, b-, and c-wave ERG amplitudes in both WT and KO mice. Age-related c-wave decline was exacerbated by Nrf2 loss. By RNAseq, two-way ANOVA of RPE-choroid samples revealed differentially expressed genes (DEGs) with age and genotype main effects, as well as DEGs with age and genotype interaction effects. Age DEGs were over-represented in pathways related to inflammation and phagocytosis. Genotype DEGs were associated with alterations in antioxidant and inflammatory processes. Retina RNAseq showed age and genotype DEGs. Conclusions: Ablation of Nrf2 exacerbates age-related declines suggesting that decrease in Nrf2 with aging has functional consequences for inflammation/resiliency. We provide retina and RPE-choroid bulk-RNAseq datasets from the same cohort of mice that can be interrogated to better understand degeneration of retina/RPE-choroid.

Background: Self-supervised learning may improve segmentation when labelled data are limited, but its benefit may depend on model and initialisation strategy. This study evaluated in-domain masked-reconstruction pretraining across limited annotation budgets. Methods: The International Skin Imaging Collaboration (ISIC) 2016 development set was partitioned into 765 images for self-supervised pretraining, 94 for fine-tuning and 41 for validation. Five nested annotation budgets (12-94 images) and five seeds were evaluated on the 379-image test set. A custom U-Net compared random and in-domain self-supervised initialisation; a ResNet-34 U-Net compared random, ImageNet, in-domain self-supervised and sequential ImageNet-to-self-supervised initialisation. Models trained with 94 labelled images were evaluated without adaptation on ISIC 2017. A separate experiment examined restoration-based pretraining. Results: In the custom U-Net, self-supervised pretraining achieved higher mean Dice than random initialisation at all five budgets, including 0.664 versus 0.615 with 12 labels and 0.811 versus 0.768 with 94 labels. Seed-level 95% confidence intervals for paired differences excluded zero at 47 and 94 labels but not at the other budgets. With 47 labels, the self-supervised model achieved mean Dice of 0.789, compared with 0.768 for random initialisation with 94 labels. In ResNet-34, ImageNet initialisation achieved higher mean Dice than in-domain self-supervised pretraining at all five budgets, and adding self-supervised pretraining after ImageNet reduced mean Dice at four of five budgets. All six 94-label configurations achieved lower mean Dice on ISIC 2017 than ISIC 2016. In the restoration experiment, mean Dice was 0.686 with random initialisation and 0.638-0.642 following pretraining. Conclusions: In-domain masked-reconstruction pretraining improved mean Dice relative to random initialisation in the custom U-Net, but not consistently in the ResNet-34 U-Net, where ImageNet initialisation performed better at every budget. Adding self-supervised pretraining after ImageNet provided no consistent gain. These findings are specific to the dermoscopic lesion-segmentation experiments and do not establish melanoma-specific diagnostic or clinical performance.

A cardinal feature of nonexudative age-related macular degeneration (AMD) is the accumulation of drusen between the retinal pigment epithelium (RPE) and Bruch's membrane, yet the mechanisms that initiate and promote drusen formation remain to be fully understood. Hydroxyapatite (HAP), a calcium-phosphate mineral identified within human drusen, has been proposed to contribute to drusen nucleation and is associated with increased likelihood of RPE atrophy. However, mechanistic studies providing insight into RPE-associated mineralization have been limited by a lack of easy-to-use and manipulatable culture models. Here, we established a rapid, inducible ARPE-19-based model of HAP mineralization. We found that ARPE-19 cells cultured in minimum essential media (MEM) supplemented with nicotinamide (NIC), sodium phosphate, and ascorbic acid (NaPAA) reproducibly formed HAP positive deposits, whereas mineralization was not observed while using standard DMEM/F12 medium, DMEM/F12 with NaPAA, MEM-NIC medium, or MEM-NIC medium with alternative osteogenic supplements (such as beta-glycerophosphate, ascorbic acid, and dexamethasone). Scanning electron microscopy with energy dispersive X ray spectroscopy demonstrated that the formed deposits were enriched in calcium (Ca) and phosphorus (P) with Ca/P ratios comparable to drusen-associated HAP deposits from AMD donor tissue. ARPE-19-based HAP deposits were also closely associated with neutral lipid-rich material, staining positive for BODIPY around their core structure. Bulk RNA sequencing of mineralized ARPE-19 cells revealed extracellular matrix, angiogenic, inflammatory, and metabolic transcriptional changes in the absence of strong enrichment of canonical osteogenic pathways. Co-treatment of mineralizing cells with either pyrophosphate, EDTA, or sodium citrate significantly reduced mineral deposition, but these approaches were not able to reverse it. Together, these findings establish a tractable RPE mineralization model that recapitulates key features of AMD-associated HAP and provides a platform for investigating mechanisms of drusen-associated mineral formation.

Introduction: Lichen sclerosus (LS) is a chronic inflammatory dermatosis predominantly affecting the anogenital region of both women and men. Sexual dysfunction remains among the most debilitating and overlooked consequences of the disease, as available patient-reported outcome measures are either restricted to one sex or capture sexual health only partially. The aim of the present work is to validate the Qualisex questionnaire (in its the Italian version) in patients with LS and to evaluate its psychometric properties, factor structure, convergent, discriminant validity, and sex symmetry. Methods: A cross-sectional study was conducted on 211 patients (167 women, 44 men; mean age 52.9 years) with a confirmed diagnosis of LS. Participants completed the Italian Qualisex, Skindex-29, DASS-21, and sexual-health-specific scales, the Female Sexual Function Index (FSFI) for women, and the International Index of Erectile Function (IIEF) for men. Construct validity was assessed via Principal Component Analysis (PCA), and reliability via Cronbach's alpha. Convergent and discriminant validities were evaluated against standard psychometric batteries. Results: Item 2 was removed due to low communality (0.167). PCA on the remaining 9 items revealed a two-factor structure accounting for 72.5% of total variance: Component 1 (Sexual Functioning and Satisfaction, 59.89%) and Component 2 (Partner Devaluation, 12.66%). Internal consistency was high (alpha= 0.911 overall; alpha= 0.841 in women; alpha= 0.899 in men). Qualisex scores correlated strongly with Skindex-29 Social Functioning (r = 0.582) and Emotions (r = 0.531) subscales, as well as FSFI (r = -0.391) and IIEF (alpha= -0.566). Discriminant validity was supported by low-to-moderate correlations with DASS-21 domains (r < 0.38). While FSFI and IIEF showed significant negative correlations with age (p = 0.002), Qualisex remained age-independent across sexes (p > 0.05). Conclusion. The 9-item Italian Qualisex is a reliable, sex-symmetrical, and age-independent patient-reported outcome measure for assessing sexual health impairment in LS, successfully isolating disease-specific distress from physiological aging and general distress.

Background: Epidemiological studies have highlighted an inverse association between cancer and Alzheimers disease (AD), but the mechanisms underlying this association are not currently understood. Amyloid precursor protein (APP) and its cleavage may represent one potential mechanism. Its importance has been heavily researched due to it giving rise to the production of amyloid-beta, a pathological hallmark of AD. APP, however, has not been extensively investigated in cancer. Methods: FFPE prostate tumour and adjacent benign tissue immunohistochemically stained for APP, androgen receptor and the insulin-like growth factor-I receptor (IGF1R). Normal prostate PNT2, androgen sensitive LNCaP and androgen insensitive PC3 in vitro were used to assess the effects of androgen, IGF-I and their inhibitors on APP and its cleavage; changes in protein abundance were measured by western blot; interactions between proteins using co-immunoprecipitation and effects on cell proliferation, apoptosis and cell signalling of APP silenced cells using a BrdU proliferation assay, Muse Cell Analyser and by TMT proteomic analysis respectively. Results: Data showed that APP was upregulated in prostate tumour tissue compared to adjacent benign. Furthermore, in cancer cell models, in contrast to normal prostate epithelial cells, it was observed that APP was critical for prostate cancer cell survival by interacting with androgen and IGF-I signalling pathways. Conclusions: Drugs that target APP have already been developed for AD and our data suggests they offer an exciting opportunity for repurposing in the treatment of prostate cancer.

Radiotherapy significantly improves the survival of head and neck cancer patients. However, it frequently damages the salivary glands, causing persistent hyposalivation and xerostomia. Radiation-induced cellular senescence within the salivary gland stem/progenitor cell niche contributes to hyposalivation, suggesting that selective elimination of senescent cells could promote tissue recovery. However, the effectiveness of senolytic compounds is strongly context dependent, varying with tissue of origin and potentially impairing regenerative cells required for functional restoration. Here, we developed a two-step organoid-based screening methodology that integrates the preferential induction of apoptosis in irradiated, senescence enriched, salivary gland organoids with the preservation of stem/progenitor cell regenerative capacity. As a first step, the senolytic activity of candidate drugs was tested to identify drugs that induced apoptosis in senescent cells of irradiated organoids but were not or less toxic to unirradiated organoids. As a second step, the confirmed senolytic compounds were tested for effects on stem cell self-renewal potential. Using this approach, we identified Nutlin3a, an MDM2 inhibitor and p53 activator, as the compound with the most favorable toxicity profile in salivary glands. Last, we confirmed the anti-senescence and pro-regenerative potential of Nutlin3a in an in vivo mouse model of radiation-induced hyposalivation, where localized Nutlin3a delivery resulted in a robust increase in saliva production, as early as two weeks after administration. These findings establish an organoid-based strategy for identifying tissue-adapted senolytic interventions and propose transient local p53 activation with Nutlin3a as a potential approach to mitigate radiation-induced salivary gland dysfunction.

Epidermodysplasia verruciformis (EV) is characterized by susceptibility to cutaneous {beta}-human papillomaviruses, persistent viral lesions and an increased risk of cutaneous squamous cell carcinoma (cSCC). We investigated whether expression of Toll-like receptors 3, 4, 5 and 9 (TLR3, TLR4, TLR5 and TLR9) differs across histological states within EV. Immunoreactivity was quantified by digital H-score using QuPath in 97 specimens from 28 patients, comprising 13 lesion-free skin samples, 15 flat warts and 69 cSCCs. Prespecified comparisons evaluated flat wart versus lesion-free skin, cSCC versus non-neoplastic tissue and invasive versus in situ cSCC, with invasive tumour differentiation assessed secondarily. Patient-clustered generalized estimating equations and false-discovery-rate (FDR) correction were used for inference. After correction for multiple testing, TLR9 H-scores were higher in flat warts than in lesion-free skin ({beta}=60.58; q=0.0332). Compared with non-neoplastic tissue, cSCC showed lower TLR3 ({beta}=-81.40; q=0.00745), higher TLR4 ({beta}=55.59; q=0.04793) and lower TLR9 expression ({beta}=-34.80; q=0.03412). TLR5 showed a nominal increase in cSCC that did not meet the FDR threshold. None of the four receptors differed significantly between invasive and in situ cSCC, and no differentiation trend remained significant after FDR correction. These findings show receptor-specific differences in TLR expression across histological states of EV, particularly involving TLR3, TLR4 and TLR9, although the diagnostic and prognostic significance of these tissue patterns remains to be established.

Breast cancer is a heterogeneous disease comprising molecular subtypes with distinct therapeutic vulnerabilities. Among emerging therapeutic strategies, copper-based nanoparticles have shown anticancer activity. However, whether these responses differ across breast cancer subtypes and which molecular programs underlie copper sensitivity remain poorly understood. We investigated subtype-specific responses to Polyvinylpyrrolidone-assisted copper nanoparticles (CuNP-PVP) in breast cancer cell lines and the molecular programs underlying copper adaptation. CuNP-PVP were synthesized and evaluated in luminal (MCF-7), HER2-positive (SKBR3), and triple-negative (MDA-MB-231) breast cancer cell lines, with transcriptomic analyses integrated with CCLE and TCGA-BRCA datasets. UV-Vis spectroscopy revealed a plasmon resonance band at 591 nm, while TEM showed spherical nanoparticles with an average diameter of 76.1 +/- 21.0 nm. DLS indicated a larger hydrodynamic diameter, consistent with PVP coating; {zeta}-potential measurements showed a surface charge of -13 mV, and XPS confirmed mixed reduced and Cu(I)/Cu(II) oxidation states. Exposure to 100 g/mL CuNP-PVP induced subtype-dependent effects on cell viability, with MCF-7 showing greater sensitivity, whereas MDA-MB-231 and SKBR3 were less affected. Baseline transcriptomic analyses revealed enrichment of oxidative stress, metabolic adaptation, and lysosomal programs in less sensitive cells, whereas MCF-7 showed higher expression of lipoylation-related genes. These features supported the development of a Potential Biological Copper-Response Index (PBCRI), which captured subtype-associated transcriptional patterns across independent cell lines and patient tumors, with luminal models showing lower scores and basal/TNBC models showing higher scores. Together, these findings identify candidate transcriptional programs associated with subtype-specific responses to CuNP and provide a framework for investigating potential molecular determinants of copper sensitivity.

Chronic alcohol consumption is associated with increased breast cancer risk; however, the long-term effects of alcohol exposure on DNA damage response (DDR) signaling and therapeutic vulnerability in breast epithelial cells remain incompletely understood. In the present study, we established a chronic alcohol exposure model using immortalized human breast epithelial MCF-10A cells to investigate persistent alterations in DNA damage signaling and sensitivity to poly (ADP-ribose) polymerase (PARP) inhibition. MCF-10A cells that chronically exposed to 0.2% alcohol for 20 weeks and then withdrew alcohol treatment for 4 weeks still retained elevated {gamma}H2AX levels and sustained activation of ATM/ATR-associated DDR pathways. Chronic alcohol-exposed cells also exhibited increased sensitivity to the PARP inhibitors olaparib and veliparib, as demonstrated by reduced cell viability, decreased clonogenic survival, and enhanced apoptosis. Mechanistically, olaparib induced greater G2/M checkpoint activation and replication-associated DNA damage in chronic alcohol-exposed cells compared with control cells. In addition, chronic alcohol exposure increased PARP expression and enhanced activation of DDR signaling following PARP inhibition. These findings demonstrate that chronic alcohol exposure induces persistent DNA repair stress and sensitizes breast epithelial cells to PARP inhibition. Our study suggests that chronic alcohol-associated genomic stress may create potential vulnerability to PARP inhibition.

Digital photography remains the gold standard for dermatological assessment, but reliance on standardized stationary image-capture systems limits trial scalability, whereas smartphones combined with computer vision artificial intelligence (AI) could enable hybrid and decentralized clinical trials (DCTs). This study assessed the facial feature grading of an AI-based system against expert panel consensus across three settings with decreasing acquisition control: Standard Studio Imaging (SSI), Clinic Smartphone Imaging (CSI), and Home Smartphone Imaging (HSI). Expert inter-rater reliability was good to excellent (median ICC 0.84-0.90), and the system showed high operator-independent test-retest repeatability across independently captured images (median ICC 0.97-0.98). Agreement with experts was maintained across all settings for macro-geometric features (ptosis {rho} = 0.74-0.81, nasolabial fold {rho} = 0.68-0.79) and for discrete pigmentation and inflammatory lesions (pigmented spot density {rho} = 0.62-0.76), declined for fine-texture features under uncontrolled acquisition (forehead wrinkles {rho} = 0.76 to 0.48), and remained limited for color-dependent features irrespective of setting. These findings support the AI-based system as an objective grading tool for a defined subset of facial endpoints in hybrid and DCTs in dermatology.

Kaposi's sarcoma (KS) is an angioproliferative tumor associated with infection by human herpesvirus 8 (HHV-8), also known as Kaposi's sarcoma-associated herpesvirus (KSHV). Among the viral genes involved in KS pathogenesis, the viral G protein-coupled receptor (vGPCR) plays a key role in oncogenic transformation and angiogenesis, and its sustained activity contributes to tumor development and maintenance. Quercetin (QUE), a naturally occurring flavonoid with well-recognized anticancer properties, has been shown to reduce cell viability and proliferation and to induce apoptosis in vGPCR-transformed endothelial cells. This study further investigated the mechanisms underlying the antineoplastic effects of QUE in vGPCR cells, an in vitro model of Kaposi's sarcoma. Initially, QUE promoted the activation of MAPK signaling pathways in vGPCR cells, increasing the phosphorylation levels of ERK1/2, JNK1/2, and p38, without affecting AKT phosphorylation. In parallel, QUE increased intracellular oxidant levels, followed by lipid peroxidation and DNA damage, supporting a link between oxidative imbalance and genotoxicity. However, increased total glutathione content, and unaltered Gpx4 mRNA expression, suggest the induction of oxidative stress and compensatory antioxidant responses. Furthermore, increased intracellular oxidant levels were associated with MAPK signaling activation, particularly JNK1/2, whereas ERK1/2 and p38 activation may reflect a compensatory response that is insufficient to overcome QUE-induced cytotoxicity. Taken together, these findings indicate that QUE exerts antiproliferative effects in vGPCR cells through a mechanism involving oxidative stress, MAPK activation, and DNA damage, supporting its potential relevance in the study of therapeutic strategies for virus-associated malignancies.