Deciphering and overcoming Anti-PD-1 resistance in Melanoma: A comprehensive review of Mechanisms, biomarker Developments, and therapeutic strategies.

Worldwide, tens of thousands of people die from melanoma each year, making it the most frequently fatal form of cutaneous cancer. Immunotherapeutic advancements, particularly with anti-PD-1 medications, have significantly enhanced treatment outcomes over recent decades. With the broad application of anti-PD-1 therapies, insights into the mechanisms of resistance have evolved. Despite the development of combination treatments and early predictive biomarkers, a comprehensive synthesis of these advancements is absent in the current literature. This review underscores the prevailing knowledge of anti-PD-1 resistance mechanisms and underscores the critical role of robust predictive biomarkers in stratifying patients for targeted combinations of anti-PD-1 and other conventional or innovative therapeutic approaches. Additionally, we offer insights that may shape future melanoma treatment strategies.

Lovastatin/SN38 co-loaded liposomes amplified ICB therapeutic effect via remodeling the immunologically-cold colon tumor and synergized stimulation of cGAS-STING pathway.

Current immune checkpoint blockade (ICB) immunotherapeutics have revolutionized cancer treatment. However, many cancers especially the "immunologically cold" tumors, do not respond to ICB, prompting the search for additional strategies to achieve durable responses. The cGAS-STING pathway, as an essential immune response pathway, has been demonstrated for a potent target to sensitize ICB immunotherapy. However, the low efficiency of conventional STING agonists limits their clinical application. Recent studies have shown that DNA topoisomerase I (TOPI) inhibitor chemodrug SN38 can activate the cGAS-STING pathway and induce an immune response through DNA damage, while the traditional statins medication lovastatin was found to inhibit DNA damage repair, which may in turn upregulate the damaged DNA level. Herein, we have developed a liposomal carrier co-loaded with SN38 and lovastatin (SL@Lip), which can be accumulated in tumors and efficiently released SN38 and lovastatin, addressing the problem of weak solubility of these two drugs. Importantly, lovastatin can increase DNA damage and enhance the activation of cGAS-STING pathway, coordinating with SN38 chemotherapy and exhibiting the enhanced combinational immunotherapy of PD-1 antibody by remodeling the tumor microenvironment in mouse colorectal cancer of both subcutaneous and orthotopic xenograft models. Overall, this study demonstrates that lovastatin-assisted cGAS-STING stimulation mediated by liposomal delivery system significantly strengthened both chemotherapy and immunotherapy of colorectal cancer, providing a clinically translational strategy for combinational ICB therapy in the "immunologically cold" tumors.

Roflumilast enhances the melanogenesis and attenuates oxidative stress-triggered damage in melanocytes.

BACKGROUND: The management of vitiligo is challenging due to limited treatment options, and therapeutic strategy varies according to the active or stable stage of vitiligo. PDE4 inhibitor has been used to treat various skin diseases, but the efficacy in vitiligo treatment is mixed. OBJECTIVE: In this study, we aimed to investigate whether roflumilast, a PDE4 inhibitor, induces melanogenesis and attenuates oxidative stress-triggered damage in melanocytes, and if so, what is the mechanism. METHODS: Melanin content assay, qRT-PCR, western blotting, ELISA, immunofluorescence assays, immunohistochemistry, small interfering RNA, flow cytometry, and transmission electron microscopy were employed. RESULTS: Our results demonstrated that roflumilast alone only slightly increased melanogenesis, however, the combination of roflumilast and forskolin could boost cAMP levels, hence promoting melanogenesis more significantly. Moreover, roflumilast attenuated H2O2-induced apoptosis and mitochondrial morphological changes in melanocytes by reducing ROS levels. Furthermore, roflumilast activated AhR/Nrf2 pathway via cAMP whereas AhR silencing blocked roflumilast-induced Nrf2 nuclear translocation and reversed the inhibitory effect of roflumilast on H2O2-induced ROS production. Finally, we observed that the lesional skin of active vitiligo patients exhibited higher PDE4 expression levels. CONCLUSION: roflumilast enhances the melanogenesis effect of forskolin and protects melanocytes from H2O2-induced apoptosis by cAMP/AhR/Nrf2-activated ROS inhibition, highlighting its therapeutic potential in vitiligo treatment.

Effect of Urinary Albumin Creatinine Ratio on Cardiovascular Morbidity and Mortality in Diabetes Patients with Atherosclerotic Disease.

Background: Diabetes mellitus (DM) patients with increased urinary albumin creatinine ratio (uACR) have higher risk of mortality, while it is unclear in DM patients with atherosclerotic cardiovascular disease (ASCVD). Methods: We analysed 2832 DM patients with ASCVD in this multi-center registry cohort study Cardiorenal ImprovemeNt II (CIN-II) in 5 Chinese tertiary hospitals from 2007 to 2020. Patients were divided into 3 groups according to their uACR level (normal group: uACR <30mg/g, moderately increased group: 30mg/g≤ uACR <300mg/g, severely increased group: 300mg/g≤ uACR). The main outcome of the study was cardiovascular mortality and all-cause mortality. Results: During a median follow-up of 2.1 years, among 2832 patients (mean age: 63.3 ± 9.9 years, 29.1% women), 434 patients (15.3%) had moderately increased uACR, and 203 patients (7.2%) had severely increased uACR. Compared to patients in normal group, patients had higher cardiovascular mortality in moderately increased group and severely increased group (2.5% vs 9.9% vs 16.7%, P < 0.001), as well as all-cause mortality. After adjusting confounders, the risk of cardiovascular mortality remained higher in moderately increased group (adjusted hazard ratio [aHR]: 3.13; 95% confidence interval [CI]: 2.04-4.81) and severely increased group (aHR: 4.54; 95% CI: 2.58-8.01) than in normal group, as well as all-cause mortality. Conclusion: In our study, we found nearly a quarter of DM patients with ASCVD had increased uACR, and they have over 2- or 3-fold risk of cardiovascular mortality than those with normal uACR. UACR is a helpful indicator for risk stratification and treatment target for DM patients with ASCVD.

Sex Differences in Characteristics, Treatments, and In-hospital Outcomes of Patients Undergoing Coronary Angiography or Intervention.

Background: Whether women have a higher risk of adverse events compared with men following coronary angiography (CAG) and percutaneous coronary intervention (PCI) remains controversial. We aimed to investigate the sex differences in characteristics, treatments and outcomes among patients undergoing CAG and PCI in a large Chinese cohort. Methods: We analyzed patients undergoing CAG and/or PCI in this multi-center registry cohort study Cardiorenal ImprovemeNt II (CIN-II) in 5 Chinese tertiary hospitals from 2007 to 2020. Clinical characteristics, treatment (discharge medication and PCI) and in-hospital outcomes (mortality and major bleeding) were compared between women and men. Results: Totally 141,459 patients underwent CAG (44,362 [31.4%] women), of which 69,345 patients underwent PCI (15,376 [22.2%] women). Women were older (64.4 vs. 60.8 years), had more chronic comorbidities and lower PCI rate for stable coronary artery disease (CAD) than men (52.8 vs. 64.2%). Women received less CAG and PCI procedures. Among women undergoing PCI they received similar discharge medication treatment. In addition, women undergoing PCI had mildly lower rate of major bleeding (0.2 vs. 0.3%, P = 0.033) but higher in-hospital mortality (1.2 vs. 0.8%, P < 0.001). After adjustment, women had a higher risk in the major bleeding (adjusted odds ratio, 2.04 [95% CI: 1.07 to 3.62]), and the in-hospital mortality (adjusted odds ratio, 1.87 [95% CI: 1.36 to 2.56]). Conclusion: Among our Chinese cohort, women are older with more chronic comorbidities, receiving less PCI procedure and similar discharge medication treatment. Women have nearly 90% higher risk of in-hospital mortality and over 1-fold increased risk of major bleeding after PCI compared with men.

Four-Octyl Itaconate Attenuates UVB-Induced Melanocytes and Keratinocytes Apoptosis by Nrf2 Activation-Dependent ROS Inhibition.

Vitiligo is an acquired skin depigmentation disease in which excessive reactive oxygen species (ROS) play a critical pathogenic role in melanocyte destruction. The complex crosstalk between melanocytes and keratinocytes in vitiligo suggests that treatments aimed at protecting both the cells might be meaningful. In this study, we investigated the effect of 4-octyl itaconate (4-OI), an itaconate derivative, on ultraviolet B- (UVB-) induced apoptosis in HaCaT and PIG1 cells and the underlying mechanisms. HaCaT and PIG1 cells were pretreated with 4-OI (50 or 100 µM) for 24 h and then exposed to 300 mJ/cm2 UVB (emission range 290-320 nm, emission peak 310 nm). ROS levels and cell apoptosis were investigated using fluorescence microscopy and flow cytometry 24 h after irradiation. In addition, nuclear translocation and the expression of pathway-related proteins and mRNAs were detected using confocal microscopy, western blotting, and qRT-PCR, respectively. Our results demonstrated that UVB induced apoptosis in HaCaT and PIG1 cells, whereas inhibition of ROS production could reverse this effect. Furthermore, 4-OI attenuated UVB-induced apoptosis in HaCaT and PIG1 cells in a concentration-dependent manner by reducing the ROS levels. Moreover, 4-OI induced nuclear translocation and activation of nuclear factor erythroid 2-related factor 2 (Nrf2), and Nrf2 silencing reversed the inhibitory effect of 4-OI on the UVB-induced increase in ROS production and apoptosis in HaCaT and PIG1 cells. In addition, in vivo experiments using the Institute of Cancer Research mouse model showed that 4-OI via tail vein injection (10 mg/kg/day for six consecutive days) could reduce skin damage induced by UVB (400 mJ/cm2/day for five consecutive days). In conclusion, 4-OI can protect melanocytes and keratinocytes from UVB-induced apoptosis by Nrf2 activation-dependent ROS inhibition and can potentially treat skin disorders associated with oxidative stress, such as vitiligo.

Identification of Serum Biomarkers and Pathways of Systemic Lupus Erythematosus with Skin Involvement Through GC/MS-Based Metabolomics Analysis.

PURPOSE: Skin involvement is the second most common symptom of systemic lupus erythematosus (SLE), and the prevention of skin lesion development might benefit to lessen the system inflammation burden in SLE. However, the mechanisms of skin lesion in SLE remain unclear. PATIENTS AND METHODS: Metabolome based on gas chromatography-mass spectrometry (GC-MS) was used for comparison of serum metabolism among 11 SLE patients with skin lesion (SL), 10 SLE patients without skin lesion (SNL), and 16 healthy controls (HC). The analysis of metabolism profiles was through LUG database, Human Metabolome Database (HMDB) as well as Kyoto Encyclopedia of Genes and Genomes (KEGG). RESULTS: A total of 14 most meaningful metabolites were found in SL patients compared to SNL patients, and 19 metabolic pathways were enriched. Meanwhile, L-alpha-aminobutyric acid, dehydroascorbic acid, glycine, and L-tyrosine achieved an area under receiver-operating characteristic (ROC) curve of 0.8636, 0.8091, 0.7727, and 0.7636, respectively, indicating their diagnostic potential for SL patients. In addition, the combined model of L-alpha-aminobutyric acid and dehydroascorbic acid provided better diagnostic accuracy. CONCLUSION: The metabolomic features of SLE patients with skin lesion could be detected by GC/MS assay. Our study tried to provide new insights into the mechanism of SLE skin injury. Further validation of these findings through larger sample size studies may contribute to the use of metabolic profile analysis.

Change of dermatological practice after the COVID-19 outbreak resolves.

AIM: Dermatological care has already been deeply impacted by the coronavirus disease-2019 (COVID-19) epidemic. The consequences may continue long after the epidemic resolves. In this study, we aimed to evaluate the change of dermatological practice since the COVID-19 outbreak is almost controlled in mainland China. MATERIAL AND METHODS: Patients requesting a dermatology outpatient visit from January to May in 2019 and 2020 were retrospectively investigated. RESULTS: The number of patients decreased significantly shortly after the COVID-19 outbreak, and it started to increase after the spread of coronavirus was gradually controlled at the end of February in China. The three most common diseases were atopic dermatitis (11.0%), acne (10.2%), and warts (7.2%) in 2019, while acne (8.9%), warts (5.8%), and acute urticaria (5.6%) in 2020. The most statistically significant increased reasons for requesting an outpatient visit from March to May in 2020 was pet-related dermatophytoses, followed by cosmetic consultation and irritated contact dermatitis, an increase of 88.2%, 84.7%, and 58.8%, respectively, over the same period of 2019. CONCLUSION: Understanding the trends and impacts of dermatologic diseases on patients and health systems during this epidemic will allow for better preparation of dermatologists in the future.

RNA-Seq Identifies Marked Th17 Cell Activation and Altered CFTR Expression in Different Atopic Dermatitis Subtypes in Chinese Han Populations.

Background: Patients with atopic dermatitis (AD) exhibit phenotypic variability in ethnicity and IgE status. In addition, some patients develop other allergic conditions, such as allergic rhinitis (AR), in subsequent life. Understanding the heterogeneity of AD would be beneficial to phenotype-specific therapies. Methods: Twenty-eight Chinese AD patients and 8 healthy volunteers were enrolled in the study. High-throughput transcriptome sequencing was conducted on lesional and nonlesional skin samples from 10 AD patients and matched normal skin samples from 5 healthy volunteers. Identification of differentially expressed genes (DEGs), KEGG pathway analyses, and sample cluster analyses were conducted in the R software environment using the DEseq2, ClusterProfiler, and pheatmap R packages, respectively. qRT-PCR, Western blotting, and ELISA were used to detect gene expression levels among subtypes. Correlation analysis was performed to further investigate their correlation with disease severity. Results: A total of 25,798 genes were detected per sample. Subgroup differential expression analysis and functional enrichment analysis revealed significant changes in the IL17 signaling pathway in Chinese EAD patients but not in IAD patients. DEGs enriched in cytokine-cytokine receptor interactions and gland secretion were considered to be associated with atopic march. Further investigations confirmed a marked IL17A upregulation in Chinese EAD with a positive relationship with total IgE level and AD severity. In addition, increased IL17A in AD patients with AR demonstrated a closer association with AR severity than IL4R. Moreover, AQP5 and CFTR were decreased in the lesions of AD patients with AR. The CFTR mRNA expression level was negatively associated with the skin IL17A level and AR severity. Conclusion: Our research characterized marked Th17 activation in Chinese EAD patients, and altered expression of IL17A, IL4R, AQP5, and CFTR in AD patients with AR was associated with AR severity. It partially explained the phenotypic differences of AD subtypes and provided potential references for endotype-targeted therapy.

Reciprocal regulation of interleukin-17A and interleukin-22 secretion through aryl hydrocarbon receptor activation in CD4+ T cells of patients with vitiligo.

Previous studies have shown the participation of the cytokines interleukin (IL) 17A and IL22 in the development of vitiligo. The aryl hydrocarbon receptor (AhR) functions in the pathogenesis of vitiligo and can modulate cytokine production. The aim of the present study was to determine the relationship between AhR activation and the secretion of IL17A and IL22 in CD4+ T cells in vitiligo. A total of 20 newly diagnosed patients with progressive, unstable vitiligo and 20 healthy controls were recruited. CD4+ T cells and skin samples were collected. Immunohistochemistry, ELISA, reverse transcription-quantitative PCR, western blotting and RNA interference experiments were performed. The expression of AhR was significantly lower in the CD4+ T cells and skin, both lesional and nonlesional, of patients with vitiligo compared with healthy subjects. AhR expression was markedly lower in nonlesional compared with lesional skin of patients with vitiligo. The expression levels of IL17A and IL22 were significantly higher in patients with vitiligo compared with healthy subjects. Knockdown of AhR significantly increased the production of IL17A and markedly decreased IL22 levels in the CD4+ T cells of patients with vitiligo. Ginkgo biloba extract EGb 761 activated AhR, inhibited IL17A secretion and enhanced IL22 release in the CD4+ T cells of patients with vitiligo. In conclusion, reduced AhR expression is associated with progressive, unstable vitiligo. Activation of AhR with G. biloba extract EGb 761 may have therapeutic potential for decreasing IL17A levels and increasing IL22 levels in patients with vitiligo.

Identification of Candidate Genes and Pathways in Nonsegmental Vitiligo Using Integrated Bioinformatics Methods.

BACKGROUND: Nonsegmental vitiligo (NSV) is an acquired depigmentation disorder of unknown origin. Enormous interests focus on finding novel biomarkers and pathways responsible for NSV. METHODS: The gene expression level was obtained by integrating microarray datasets (GSE65127 and GSE75819) from the Gene Expression Omnibus database using the sva R package. Differentially expressed genes (DEGs) between each group were identified by the limma R package. The interaction network was constructed using STRING, and significant modules coupled with hub genes were identified by cytoHubba and molecular complex detection. Pathway analyses were conducted using generally applicable gene set enrichment and further visualized in R environment. RESULTS: A total of 102 DEGs between vitiligo lesional skin and healthy skin, 14 lesion-specific genes, and 29 predisposing genes were identified from the integrated dataset. Except for the anticipated decrease in melanogenesis, three major functional changes were identified, including oxidative phosphorylation, p53, and peroxisome proliferator-activated receptor (PPAR) signaling in lesional skin. PPARG, MUC1, S100A8, and S100A9 were identified as key hub genes involved in the pathogenesis of vitiligo. Besides, upregulation of the T cell receptor signaling pathway was considered to be associated with susceptibility of the skin in NSV patients. CONCLUSION: Our study reveals several potential pathways and related genes involved in NSV using integrated bioinformatics methods. It might provide references for targeted strategies for NSV.

Astragaloside IV Enhances Melanogenesis via the AhR-Dependent AKT/GSK-3ß/ß-Catenin Pathway in Normal Human Epidermal Melanocytes.

Astragalus membranaceus root has been widely used for repigmentation treatment in vitiligo, but its mechanism is poorly understood. We sought to investigate the effect of astragaloside IV (AS-IV), a main active extract of the Astragalus membranaceus root, on melanin synthesis in normal human epidermal melanocytes (NHEMs) and to elucidate its underlying mechanisms. Melanin content, tyrosinase activity, qPCR, western blot, and immunofluorescence were employed. Specific inhibitors and small interfering RNA were used to investigate the possible pathway. AS-IV stimulated melanin synthesis and upregulated the expression of melanogenesis-related genes in a concentration-dependent manner in NHEMs. AS-IV could activate the aryl hydrocarbon receptor (AhR), and AS-IV-induced melanogenesis was inhibited in si-AhR-transfected NHEMs. In addition, we showed that AS-IV enhanced the phosphorylation of AKT and GSK-3ß and nuclear translocation of ß-catenin. AS-IV-induced MITF expression upregulation and melanin synthesis were decreased in the presence of ß-catenin inhibitor FH353. Furthermore, AhR antagonist CH223191 inhibited the activation of AKT/GSK-3ß/ß-catenin signaling, whereas the expression of CYP1A1 (marker of AhR activation) was not affected by the AKT inhibitor in AS-IV-exposed NHEMs. Our findings show that AS-IV induces melanogenesis through AhR-dependent AKT/GSK-3ß/ß-catenin pathway activation and could be beneficial in the therapy for depigmented skin disorders.