Adjuvant and Neoadjuvant Therapies in Cutaneous Melanoma

Leveraging single-cell sequencing analysis and bulk-RNA sequencing analysis to forecast necroptosis in cutaneous melanoma prognosis

Cutaneous melanoma, a malignancy of melanocytes, presents a significant challenge due to its aggressive nature and rising global incidence. Despite advancements in treatment, the variability in patient responses underscores the need for further research into novel therapeutic targets, including the role of programmed cell death pathways such as necroptosis. The melanoma datasets used for analysis, GSE215120, GSE19234, GSE22153 and GSE65904, were downloaded from the GEO database. The melanoma data from TCGA were downloaded from the UCSC website. Using single-cell sequencing, we assess the heterogeneity of necroptosis in cutaneous melanoma, identifying distinct cell clusters and necroptosis-related gene expression patterns. A combination of 101 machine learning algorithms was employed to construct a necroptosis-related signature (NRS) based on key genes associated with necroptosis. The prognostic value of NRS was evaluated in four cohorts (one TCGA and three GEO cohorts), and the tumour microenvironment (TME) was analysed to understand the relationship between necroptosis, tumour mutation burden (TMB) and immune infiltration. Finally, we focused on the role of key target TSPAN10 in the prognosis, pathogenesis, immunotherapy relevance and drug sensitivity of cutaneous melanoma. Our study revealed significant heterogeneity in necroptosis among melanoma cells, with a higher prevalence in epithelial cells, myeloid cells and fibroblasts. The NRS, developed through rigorous machine learning techniques, demonstrated robust prognostic capabilities, distinguishing high-risk patients with poorer outcomes in all cohorts. Analysis of the TME showed that high NRS scores correlated with lower TMB and reduced immune cell infiltration, indicating a potential mechanism through which necroptosis influences melanoma progression. Finally, TSPAN10 has been identified as a key target for cutaneous melanoma and is highly associated with poor prognosis. The findings highlight the complex role of necroptosis in cutaneous melanoma and introduce the NRS as a novel prognostic tool with potential to guide therapeutic decisions.

Salidroside induces mitochondrial dysfunction and ferroptosis to inhibit melanoma progression through reactive oxygen species production

Reactive oxygen species (ROS) induces necroptotic and ferroptosis in melanoma cells. Salidroside (SAL) regulates ROS in normal cells and inhibits melanoma cell proliferation. This study used human malignant melanoma cells treated with SAL either alone or in combination with ROS scavenger (NAC) or ferroptosis inducer (Erastin). Through cell viability, wound healing assays, and a Seahorse analyze found that SAL inhibited cell proliferation, migration, extracellular acidification rate, and oxygen consumption rate. Metabolic flux analysis, complexes I, II, III, and IV activity of the mitochondrial respiratory chain assays, mitochondrial membrane potential assay, mitochondrial ROS, and transmission electron microscope revealed that SAL induced mitochondrial dysfunction and ultrastructural damage. Assessment of malondialdehyde, lipid ROS, iron content measurement, and Western blot analysis showed that SAL activated lipid peroxidation and promoted ferroptosis in A-375 cells. These effects were abolished after NAC treatment. Additionally, SAL and Erastin both inhibited cell proliferation and promoted cell death; SAL increased the Erastin sensitivity of cells while NAC antagonized it. In xenograft mice, SAL inhibited melanoma growth and promoted ROS-dependent ferroptosis. SAL induced mitochondrial dysfunction and ferroptosis to block melanoma progression through ROS production, which offers a scientific foundation for conducting SAL pharmacological research in the management of melanoma.

Identification of anoikis-related subtypes and development of risk stratification system in skin cutaneous melanoma

Background

Anoikis, a form of apoptosis induced by cell detachment, plays a key role in cancer metastasis. However, the potential roles of anoikis-related genes (ARGs) in assessing the prognosis of skin cutaneous melanoma (SKCM) and the tumor microenvironment (TME) remain unclear.

Methods

The data from TCGA corresponding to transcriptomic expression patterns for patients with SKCM were downloaded and utilized to screen distinct molecular subtypes by a non-negative matrix factorization algorithm. The prognostic signature was constructed by least absolute shrinkage and selection operator (LASSO) Cox regression and was validated in SKCM patients from the GEO cohort. Moreover, the relationship of the ARG_score with prognosis, tumor-infiltrating immune cells, gene mutation, microsatellite instability (MSI), and immunotherapy efficacy.

Results

We screened 100 anoikis-related differentially expressed genes between SKCM tissues and normal skin tissues, which could divide all patients into three different subtypes with significantly distinct prognosis and immune cell infiltration. Then, an anoikis-related signature was developed based on subtype-related DEGs, which could classify all SKCM patients into low and high ARG_score groups with differing overall survival (OS) rates. ARG_score was confirmed to be a strong independent prognostic indicator for SKCM patients. By combining ARG_score with clinicopathological features, a nomogram was constructed, which could accurately predict the individual OS of patients with SKCM. Moreover, low ARG_score patients presented with higher levels of immune cell infiltration, TME score, higher tumor mutation burden, and better immunotherapy responses.

Conclusions

Our comprehensive analysis of ARGs in SKCM provides important insights into the immunological microenvironment within the tumor of SKCM patients and helps to forecast prognosis and the response to immunotherapy in SKCM patients, thereby making it easier to tailor more effective treatment strategies to individual patients.

Patients with melanoma treated with immune checkpoint inhibitors who had non-thyroid endocrine and skin immune-related adverse events have better prognosis: A systematic review and meta-analysis

Background

Several studies have reported an association between the occurrence of immune-related adverse events (irAEs) and prognosis in patients with melanoma treated with immune checkpoint inhibitors (ICIs), but the results remain controversial. We conducted a systematic review and meta-analysis to investigate the association between irAEs and survival in patients with melanoma treated with ICIs.

Methods

We searched the PubMed, Web of Science, and China National Knowledge Infrastructure databases through May 5, 2022 for clinical studies evaluating the association between irAEs and in melanoma patients treated with ICIs. Combined hazard ratios (HRs) for overall survival (OS) and progression-free survival (PFS) were calculated using fixed- or random-effects models based on heterogeneity.

Results

A total of 60 articles were included, with 16,520 patients. In patients with melanoma treated with ICIs, the occurrence of irAEs was significantly associated with better OS (HR, 0.58; 95% confidence interval [CI], 0.51–0.66; P<0.00001) and PFS (HR, 0.61; 95%CI, 0.51–0.72; P<0.00001). Endocrine irAEs (OS, HR, 0.81; 95%CI, 0.72–0.92; P=0.001; PFS: HR, 0.84; 95%CI, 0.73–0.96, P=0.009), skin irAEs (OS, HR, 0.59; 95%CI, 0.41–0.85; P=0.004; PFS: HR, 0.43; 95%CI, 0.36–0.52; P<0.00001), vitiligo (OS, HR, 0.22; 95%CI, 0.15–0.31; P<0.00001; PFS, HR, 0.33; 95%CI, 0.25–0.44; P<0.00001), and grade 1–2 irAEs (OS, HR, 0.67; 95%CI, 0.58–0.78; P<0.00001; PFS, HR, 0.62; 95%CI, 0.51–0.76; P<0.00001) showed similar results. However, thyroid, lung, gastrointestinal, liver, and grade 3–4 irAEs were not significantly associated with OS and PFS. The occurrence of non-thyroid endocrine irAEs was significantly associated with better OS (HR, 0.22; 95%CI, 0.15–0.31; P<0.00001). In patients with melanoma treated with anti-programmed cell death protein 1 (OS, HR, 0.61; 95%CI, 0.51–0.72; P<0.00001; PFS, HR, 0.59; 95%CI, 0.47–0.74; P<0.00001), the association between irAEs and clinical benefit was clearer than in patients treated with anti-cytotoxic T-lymphocyte-associated protein 4 (OS, HR, 0.68; 95%CI, 0.52–0.89; P=0.005; PFS, HR, 0.93; 95%CI, 0.49–1.78; P=0.83).

Conclusion

Among patients with melanoma treated with ICIs, those who developed non-thyroid endocrine irAEs and cutaneous irAEs have better prognosis. This suggests that non-thyroid endocrine irAEs and cutaneous irAEs may be a prognostic biomarker for patients with melanoma treated with ICIs.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022338308.