Identification of novel disulfidptosis-related lncRNA signatures to predict the prognosis and immune microenvironment of skin cutaneous melanoma patients.

BACKGROUND: Skin cutaneous melanoma (SKCM) is an aggressive form of malignant melanoma with poor prognosis and high mortality rates. Disulfidptosis is a newly discovered cell death regulatory mechanism caused by the abnormal accumulation of disulfides. This unique pathway is guiding significant new research to understand cancer progression for targeted treatment. However, the correlation between disulfidptosis with long non-coding RNAs (lncRNAs) in SKCM remains unknown at present. METHODS: The Cancer Genome Atlas database furnished lncRNA expression data and clinical information for SKCM patients. Pearson correlation and Cox regression analyses identified disulfidptosis-related lncRNAs associated with SKCM prognosis. ROC curves and a nomogram validated the model. TME, immune infiltration, GSEA analysis, immune checkpoint gene expression profiling, and drug sensitivity were assessed in high and low-risk groups. Consistent clustering categorized SKCM patients for personalized clinical treatment guidance. RESULTS: A total of twelve disulfidptosis-related lncRNAs were identified for the development of prognosis prediction models. The area under the curve (AUC) values of the ROC curve and the nomogram provided reliable discrimination to evaluate the prognostic potential for SKCM patients. The TME played a crucial role in tumorigenesis, progression and prognosis, and the risk scores were closely related to immune cell infiltration. Meanwhile, the combination of chemotherapy, targeted therapy, and immunotherapy was recommended for low-risk patients based on drug sensitivity and immune efficacy analyses. CONCLUSION: We identified a risk model of twelve disulfidptosis-related lncRNAs that could be used to predict the prognosis of SKCM patients and help guide immunotherapy and chemotherapy for personalized treatment plans.

Real-world incidences and risk factors of immune-related adverse events in patients treated with immune checkpoint inhibitors: A nationwide retrospective cohort study.

Immune-related adverse events (irAEs) caused by immune checkpoint inhibitors (ICIs) are rare but fatal, requiring systemic steroid use. Therefore, to examine the outcomes, incidence, timing, and risk factors of ICI-associated steroid-requiring severe irAEs, we conducted a nationwide, retrospective, cohort study utilizing the Korean Health Insurance and Review Assessment database. We identified 357,010 patients with lung cancer, bladder cancer, or skin melanoma, eligible for ICI reimbursement in Korea between January 2012 to June 2020. Steroid-requiring severe irAEs following ICI treatment or treatment-emergent AEs following cytotoxic chemotherapy were defined as moderate- or high-dose steroid administration for over 2 consecutive days, along with corresponding ICD-10 codes indicating affected organ systems. The ICI-exposed group (N = 10,118) was compared to a matched cohort of 55,436 ICI-unexposed patients treated with cytotoxic chemotherapy. Incidences of acute severe irAEs requiring moderate- and high-dose steroids were higher in the ICI-exposed group (1.95% and 6.42%, respectively). The ICI-exposed group also had a higher risk of developing delayed severe irAEs requiring moderate- and high-dose steroid use (3.89% and 7.39%). Male sex, high comorbidity index, or previously diagnosed autoimmune diseases were associated with an increased risk of severe irAEs. Notably, 27.4-38.8% of the patients experienced recurrent severe irAEs after re-challenge with ICIs following moderate- or high-dose steroid use, with the severity matching the initial episode. Steroid-requiring severe irAEs were significantly more prevalent among patients exposed to ICIs than among those treated with chemotherapy in acute and delayed periods.

Tumor-Infiltrating T Cells in Skin Basal Cell Carcinomas and Squamous Cell Carcinomas: Global Th1 Preponderance with Th17 Enrichment-A Cross-Sectional Study.

Basal cell carcinomas (BCCs) and squamous cell carcinomas (SCCs) are high-incidence, non-melanoma skin cancers (NMSCs). The success of immune-targeted therapies in advanced NMSCs led us to anticipate that NMSCs harbored significant populations of tumor-infiltrating lymphocytes with potential anti-tumor activity. The main aim of this study was to characterize T cells infiltrating NMSCs. Flow cytometry and immunohistochemistry were used to assess, respectively, the proportions and densities of T cell subpopulations in BCCs (n = 118), SCCs (n = 33), and normal skin (NS, n = 30). CD8+ T cells, CD4+ T cell subsets, namely, Th1, Th2, Th17, Th9, and regulatory T cells (Tregs), CD8+ and CD4+ memory T cells, and γδ T cells were compared between NMSCs and NS samples. Remarkably, both BCCs and SCCs featured a significantly higher Th1/Th2 ratio (~four-fold) and an enrichment for Th17 cells. NMSCs also showed a significant enrichment for IFN-γ-producing CD8+T cells, and a depletion of γδ T cells. Using immunohistochemistry, NMSCs featured denser T cell infiltrates (CD4+, CD8+, and Tregs) than NS. Overall, these data favor a Th1-predominant response in BCCs and SCCs, providing support for immune-based treatments in NMSCs. Th17-mediated inflammation may play a role in the progression of NMSCs and thus become a potential therapeutic target in NMSCs.

Developing a prognostic model for skin melanoma based on the persistent tumor mutation burden and determining IL17REL as a therapeutic target.

BACKGROUND: One popular and well-established marker for the immune checkpoint blockade (ICB) response is tumor mutation burden (TMB). Persistent TMB (pTMB), a subset of TMB, provides a better indicator to predict patient ICB therapy outcomes, as shown by some studies. Immune checkpoint drugs have significantly changed how melanoma is treated in recent years. METHODS: In this study, we integrated the TCGA-SKCM database and data of pTMB of TCGA from the paper that first mentioned pTMB and analyzed mutational and Immune characteristics associated with pTMB level in SKCM. Next, the predictive DEGs were identified the subgroups of pTMB by Cox regression and LASSO analyses to construct a pTMB-related signature. Finally, the expression and Biological functions of signature genes was detected, and further validated in vitro assay. RESULTS: In the current research, we explored the mutational and immunological features related to the level of TMB in cutaneous melanoma (CM). The high-pTMB subgroup exhibited an increasing incidence of gene changes and higher levels of immune cell infiltration. Subsequently, we established a pTMB-related signature based on the predictive DEGs and found the biological features and immune-associated variables between two distinct risk groups. Lastly, the results of the clinical sample validation demonstrated that the expression of IL17REL was down-regulated in the collected samples of individuals with CM. The in vitro assay results indicated that IL17REL effectively suppressed the proliferation, clonality, and migration of CM cells. CONCLUSION: In conclusion, we have developed a prediction model associated with TMB and subsequently validated the potential influence of IL17REL on Overall Survival (OS) in patients diagnosed with melanoma.

Developing Engineered Nano-Immunopotentiators for the Stimulation of Dendritic Cells and Inhibition and Prevention of Melanoma.

OBJECTIVE: This study aims to utilize PEGylated poly (lactic-co-glycolic acid) (PLGA) nanoparticles as a delivery system for simultaneous administration of the BRAFV600E peptide, a tumor-specific antigen, and imiquimod (IMQ). The objective is to stimulate dendritic cell (DC) maturation, activate macrophages, and facilitate antigen presentation in C57BL6 mice. METHODS: PEG-PLGA-IMQ-BRAFV600E nanoparticles were synthesized using a PLGA-PEG-PLGA tri-block copolymer, BRAFV600E, and IMQ. Characterization included size measurement and drug release profiling. Efficacy was assessed in inhibiting BPD6 melanoma cell growth and activating immature bone marrow DCs, T cells, macrophages, and splenocyte cells through MTT and ELISA assays. In vivo, therapeutic and immunogenic effects potential was evaluated, comparing it to IMQ + BRAFV600E and PLGA-IMQ-BRAFV600E nanoparticles in inhibiting subcutaneous BPD6 tumor growth. RESULTS: The results highlight the successful synthesis of PEG-PLGA-IMQ-BRAFV600E nanoparticles (203 ± 11.1 nm), releasing 73.4% and 63.2% of IMQ and BARFV600E, respectively, within the initial 48 h. In vitro, these nanoparticles demonstrated a 1.3-fold increase in potency against BPD6 cells, achieving ~ 2.8-fold enhanced cytotoxicity compared to PLGA-IMQ-BRAFV600E. Moreover, PEG-PLGA-IMQ-BRAFV600E exhibited a 1.3-fold increase in potency for enhancing IMQ cytotoxic effects and a 1.1- to ~ 2.4-fold increase in activating DCs, T cells, macrophages, and splenocyte cells compared to IMQ-BRAFV600E and PLGA-IMQ-BRAFV600E. In vivo, PEG-PLGA-IMQ-BRAFV600E displayed a 1.3- to 7.5-fold increase in potency for inhibiting subcutaneous BPD6 tumor growth compared to the other formulations. CONCLUSIONS: The findings suggest that PEG-PLGA nanoparticles effectively promote DC maturation, T cell activation, and potentially macrophage activation. The study highlights the promising role of this nanocomposite in vaccine development.

Cancer cell plasticity defines response to immunotherapy in cutaneous squamous cell carcinoma.

Immune checkpoint blockade (ICB) approaches have changed the therapeutic landscape for many tumor types. However, half of cutaneous squamous cell carcinoma (cSCC) patients remain unresponsive or develop resistance. Here, we show that, during cSCC progression in male mice, cancer cells acquire epithelial/mesenchymal plasticity and change their immune checkpoint (IC) ligand profile according to their features, dictating the IC pathways involved in immune evasion. Epithelial cancer cells, through the PD-1/PD-L1 pathway, and mesenchymal cancer cells, through the CTLA-4/CD80 and TIGIT/CD155 pathways, differentially block antitumor immune responses and determine the response to ICB therapies. Accordingly, the anti-PD-L1/TIGIT combination is the most effective strategy for blocking the growth of cSCCs that contain both epithelial and mesenchymal cancer cells. The expression of E-cadherin/Vimentin/CD80/CD155 proteins in cSCC, HNSCC and melanoma patient samples predicts response to anti-PD-1/PD-L1 therapy. Collectively, our findings indicate that the selection of ICB therapies should take into account the epithelial/mesenchymal features of cancer cells.

The Expression of Forkhead Box P3 T Regulatory Lymphocytes as a Prognostic Factor in Malignant Melanomas.

Since transcription factor Forkhead Box P3 (FoxP3) was identified as a specific regulatory T cell (Treg) marker, researchers have scrutinized its value as a potential novel therapeutic target or a prognostic factor in various types of cancer with inconsistent results. The present analysis was performed to assess the influence of Treg FoxP3 expression on the prognosis of primary melanoma and to evaluate the correlations with various clinicopathological prognostic factors. We analyzed all eligible patients with stage pT3 primary malignant melanomas treated in a tertiary cancer center. Immunohistochemical staining for Treg FoxP3 expression was performed on retrospectively identified paraffin blocks and subsequently correlated with the outcomes of the patients. A total of 81% of the patients presented a positive Treg FoxP3 expression, being correlated with a higher risk of lymph node metastasis, tumor relapse, and death. Moreover, positive expression was statistically associated with a shorter OS. The tumor relapse rate was estimated at 36.7%. A positive expression of Treg FoxP3 and lymph node metastasis were associated with a higher risk of death based on multivariate analysis. Treg FoxP3 expression may be used as an independent prognostic factor in patients with malignant melanoma to evaluate tumor progression and survival.

Development of a biomarker signature associated with anoikis to predict prognosis and immunotherapy response in melanoma.

Skin cutaneous melanoma (SKCM) is malignant cancer known for its high aggressiveness and unfavorable prognosis, particularly in advanced tumors. Anoikis is a specific pattern of programmed cell death associated with tumor regeneration, migration, and metastasis. Nevertheless, limited research has been conducted to investigate the function of anoikis in SKCM. Anoikis-related genes (ARGs) were extracted from Genecards to identify SKCM subtypes and to explore the immune microenvironment between the different subtypes. Prognostic models of SKCM were developed by LASSO COX regression analysis. Subsequently, the predictive value of risk scores in SKCM and the association with immunotherapy were further explored. Finally, the expression of 6 ARGs involved in the model construction was detected by immunohistochemistry and PCR. This study identified 20 ARGs significantly associated with SKCM prognosis and performed disease subtype analysis of samples based on these genes, different subtypes exhibited significantly different clinical features and tumor immune microenvironment (TIME) landscapes. The risk score prognostic model was generated by further screening and identification of the six ARGs. The model exhibited a high degree of sensitivity and specificity to predict the prognosis of individuals with SKCM. These high- and low-risk populations showed different immune statuses and drug sensitivity. Further immunohistochemical and PCR experiments identified significant differential expression of the six ARGs in tumor and normal samples. Anoikis-based features may serve as novel prognostic biomarkers for SKCM and may provide important new insights for survival prediction and individualized treatment development.

Based on scRNA-seq and bulk RNA-seq to establish tumor immune microenvironment-associated signature of skin melanoma and predict immunotherapy response.

Skin cutaneous melanoma (SKCM), a form of skin cancer, ranks among the most formidable and lethal malignancies. Exploring tumor microenvironment (TME)-based prognostic indicators would help improve the efficacy of immunotherapy for SKCM patients. This study analyzed SKCM scRNA-seq data to cluster non-malignant cells that could be used to explore the TME into nine immune/stromal cell types, including B cells, CD4 T cells, CD8 T cells, dendritic cells, endothelial cells, Fibroblasts, macrophages, neurons, and natural killer (NK) cells. Using data from The Cancer Genome Atlas (TCGA), we employed SKCM expression profiling to identify differentially expressed immune-associated genes (DEIAGs), which were then incorporated into weighted gene co-expression network analysis (WGCNA) to investigate TME-associated hub genes. Discover candidate small molecule drugs based on pivotal genes. Tumor immune microenvironment-associated genes (TIMAGs) for constructing TIMAS were identified and validated. Finally, the characteristics of TIAMS subgroups and the ability of TIMAS to predict immunotherapy outcomes were analyzed. We identified five TIMAGs (CD86, CD80, SEMA4D, C1QA, and IRF1) and used them to construct TIMAS. In addition, five potential SKCM drugs were identified. The results showed that TIMAS-low patients were associated with immune-related signaling pathways, high MUC16 mutation frequency, high T cell infiltration, and M1 macrophages, and were more favorable for immunotherapy. Collectively, TIMAS constructed by comprehensive analysis of scRNA-seq and bulk RNA-seq data is a promising marker for predicting ICI treatment outcomes and improving individualized therapy for SKCM patients.

Unravelling drivers of cutaneous squamous cell carcinoma in recessive dystrophic epidermolysis bullosa.

Epidermolysis bullosa (EB) is an umbrella term for a group of rare inherited skin disorders characterised by mucocutaneous fragility. Patients suffer from blisters and chronic wounds that arise spontaneously or following minor mechanical trauma, often resulting in inflammation, scarring and fibrosis due to poor healing. The recessive form of dystrophic EB (RDEB) has a particularly severe phenotype and is caused by mutations in the COL7A1 gene, encoding the collagen VII protein, which is responsible for adhering the epidermis and dermis together. One of the most feared and devastating complications of RDEB is the development of an aggressive form of cutaneous squamous cell carcinoma (cSCC), which is the main cause of mortality in this patient group. However, pathological drivers behind the development and progression of RDEB-associated cSCC (RDEB-cSCC) remain somewhat of an enigma, and the evidence to date points towards a complex process. Currently, there is no cure for RDEB-cSCC, and treatments primarily focus on prevention, symptom management and support. Therefore, there is an urgent need for a comprehensive understanding of this cancer's pathogenesis, with the aim of facilitating the discovery of drug targets. This review explores the current knowledge of RDEB-cSCC, emphasising the important role of the immune system, genetics, fibrosis, and the tumour-promoting microenvironment, all ultimately intricately interconnected.

Administration of intratumoral GD2-directed interleukin-2 immunocytokine and local radiation therapy to activate immune rejection of spontaneous canine melanoma.

Canine malignant melanoma provides a clinically relevant, large animal parallel patient population to study the GD2-reactive hu14.18-IL-2 immunocytokine as it is similar to human melanoma and expresses GD2. The objectives of this study were to evaluate safety, radiation fractionation, and identify informative biomarkers of an in-situ tumor vaccine involving local radiation therapy plus intratumoral-immunocytokine in melanoma tumor-bearing dogs. Twelve dogs (six dogs/arm) with locally advanced or metastatic melanoma were randomized to receive a single 8 Gy fraction (arm A) or three 8 Gy fractions over 1 week (arm B) to the primary site and regional lymph nodes (when clinically involved) with the single or last fraction 5 days before intratumoral-immunocytokine at 12 mg/m 2 on 3 consecutive days. Serial tumor biopsies were obtained. All 12 dogs completed protocol treatment, and none experienced significant or unexpected adverse events. Evidence of antitumor activity includes one dog with a complete response at day 60, one dog with a partial response at day 60, and four dogs with mixed responses. Histology of serial biopsies shows a variably timed increase in intratumoral lymphocytic inflammation in some dogs. Canine NanoString analyses of serial biopsies identified changes in gene signatures of innate and adaptive cell types versus baseline. There were no significant differences in NanoString results between arm A and arm B. We conclude that intratumoral-immunocytokine in combination with local radiation therapy in canine melanoma is well tolerated and has antitumor activity with the potential to inform clinical development in melanoma patients.

Low skeletal muscle mass predicts melanoma-specific survival in melanoma patients treated with adjuvant immune checkpoint blockade.

PURPOSE: Adjuvant immunotherapy with immune checkpoint blockade(ICB) has greatly reduced the risk of recurrence and metastatic spread in early and advanced melanoma. However, not all patients benefit from adjuvant treatment: many patients show disease recurrence despite therapy, while those without recurrence harbor the risk for potentially irreversible adverse events. Biomarkers to select patients benefitting most from adjuvant therapy are currently lacking. As body composition assessment using CT images has shown promising results as a prognostic biomarker in stage IV melanoma, we aim to study the applicability of body composition parameters also in adjuvant melanoma treatment. METHODS: We analyze body composition features via CT scans in a retrospective cohort of 109 patients with resected stage IIB-IV melanoma receiving an adjuvant first-line treatment with ICB in our department. In this analysis, we focus on the impact of body composition, especially the presence of low skeletal muscle mass (LSMM), on patients' survival and occurrence of adverse events (AEs). RESULTS: In uni- and multivariate analyses, we identify an association between CT-measured LSMM and melanoma-specific survival in patients treated with adjuvant ICB. Furthermore, LSMM is associated with a lower risk for therapy-related AEs, especially hypothyroidism, fatigue, and xerostomia. Conventional serological biomarkers e.g. S100 and LDH and measures of adipose tissue compartments did not show a correlation with survival or the occurrence of AEs. CONCLUSIONS: LSMM constitutes a novel biomarker for melanoma-specific survival in patients treated with adjuvant ICB.

Proteomic analysis of pleomorphic dermal sarcoma reveals a fibroblastic cell of origin and distinct immune evasion mechanisms.

Pleomorphic dermal sarcomas are infrequent neoplastic skin tumors, manifesting in regions of the skin exposed to ultraviolet radiation. Diagnosing the entity can be challenging and therapeutic options are limited. We analyzed 20 samples of normal healthy skin tissue (SNT), 27 malignant melanomas (MM), 20 cutaneous squamous cell carcinomas (cSCC), and 24 pleomorphic dermal sarcomas (PDS) using mass spectrometry. We explored a potential cell of origin in PDS and validated our findings using publicly available single-cell sequencing data. By correlating tumor purity (TP), inferred by both RNA- and DNA-sequencing, to protein abundance, we found that fibroblasts shared most of the proteins correlating to TP. This observation could also be made using publicly available SNT single cell sequencing data. Moreover, we studied relevant pathways of receptor/ligand (R/L) interactions. Analysis of R/L interactions revealed distinct pathways in cSCC, MM and PDS, with a prominent role of PDGFRB-PDGFD R/L interactions and upregulation of PI3K/AKT signaling pathway. By studying differentially expressed proteins between cSCC and PDS, markers such as MAP1B could differentiate between these two entities. To this end, we studied proteins associated with immunosuppression in PDS, uncovering that immunologically cold PDS cases shared a "negative regulation of interferon-gamma signaling" according to overrepresentation analysis.

Integrative molecular and spatial analysis reveals evolutionary dynamics and tumor-immune interplay of in situ and invasive acral melanoma.

In acral melanoma (AM), progression from in situ (AMis) to invasive AM (iAM) leads to significantly reduced survival. However, evolutionary dynamics during this process remain elusive. Here, we report integrative molecular and spatial characterization of 147 AMs using genomics, bulk and single-cell transcriptomics, and spatial transcriptomics and proteomics. Vertical invasion from AMis to iAM displays an early and monoclonal seeding pattern. The subsequent regional expansion of iAM exhibits two distinct patterns, clonal expansion and subclonal diversification. Notably, molecular subtyping reveals an aggressive iAM subset featured with subclonal diversification, increased epithelial-mesenchymal transition (EMT), and spatial enrichment of APOE+/CD163+ macrophages. In vitro and ex vivo experiments further demonstrate that APOE+CD163+ macrophages promote tumor EMT via IGF1-IGF1R interaction. Adnexal involvement can predict AMis with higher invasive potential whereas APOE and CD163 serve as prognostic biomarkers for iAM. Altogether, our results provide implications for the early detection and treatment of AM.

Vaccimel immunization is associated with enhanced response to treatment with anti-PD-1 monoclonal antibodies in cutaneous melanoma patients - a case reports study.

Cancer vaccines are gaining ground as immunotherapy options. We have previously demonstrated in cutaneous melanoma (CM) patients that adjuvant treatment with VACCIMEL, a mixture of four irradiated CM cell lines co-adjuvanted with BCG and GM-CSF, increases the cellular immune response to melanocyte differentiation antigens, cancer-testis antigens and neoantigens, with respect to basal levels. On the other hand, it is also known that treatment with anti-PD-1 monoclonal antibodies (MAbs), acting on pre-existing tumor-reactive lymphocytes, induces clinical responses in CM patients, albeit in a fraction of treated patients. A combination of both treatments would appear therefore desirable. In this paper, we describe CM patients who, having progressed even years after vaccination, were treated with anti-PD-1 MAbs. In 5/5 of such progressor patients, complete responses were obtained which lasted between 3 and 65+ months. Three of the patients remain disease-free and two recurred. One of the patients passed away after a recurrence of brain metastases. We suggest that clonally expanded reactive lymphocytes induced by VACCIMEL partially remain as memory cells, which may be recalled after tumor recurrence and may foster ulterior activity of anti-PD-1 MAbs.

The Immune Response of Cutaneous Basosquamous- and Squamous-Cell Carcinoma Associated with Sun Exposure.

In recent years, there has been an observed increase in the frequency of cutaneous carcinoma, which correlates with sun exposure. This study aims to explore the variances of tumor characteristics and immune response markers among patients diagnosed with cutaneous squamous-cell carcinoma (SCC) and basosquamous-cell carcinoma (BSC) with varying levels of sun exposure. The objective is to elucidate the potential influence of sun exposure on tumor progression and immune response in these types of carcinomas. We conducted a retrospective observational study that included 132 patients diagnosed with SCC and BSC. Participants were separated into high- and low-sun exposure groups. Tumor characteristics and immune response markers, including lymphocyte percentage (LY%), neutrophil-to-lymphocyte ratio (NLR), and lymphocyte-to-monocyte ratio (LMR), were assessed using the Mann-Whitney U test. Our findings revealed the interplay between sun exposure, inflammation, aging, and immune response. In 80% of cases, it was found that individuals had high sun exposure throughout their lifetime. Patients in the high sun exposure category had a significantly higher LY% than those with low sun exposure (24.22 ± 7.64 vs. 20.71 ± 8.10, p = 0.041). Also, the NLR was lower in patients with high sun exposure (3.08 ± 1.47 vs. 3.94 ± 2.43, p = 0.023). Regarding inflammatory markers, the erythrocyte sedimentation rate (ESR), LY%, NLR, and LMR showed significant differences between the two groups. Patients who were diagnosed with SCC had higher ESR values (p = 0.041), higher LY% (p = 0.037), higher NLR (p = 0.041), and lower LMR (p = 0.025). This study provides evidence supporting distinct tumor characteristics and immune response patterns in patients diagnosed with SCC and BSC with a high sun exposure history. These findings imply that sun exposure may contribute to tumor progression and influence the immune response in individuals with SCC and BSC.