Melanoma and subcutaneous adipose tissue: Role of peritumoral adipokines in disease characterization and prognosis

Association between triglyceride‑glucose index as a marker of insulin resistance and the risk of malignant melanoma: A retrospective study

Malignant melanoma, a highly malignant tumor predominantly found on the skin surface, has exhibited an alarming rise in both incidence and mortality rates annually since 2012. Despite its relatively low occurrence among skin malignancies, the mortality rate of malignant melanoma remains disproportionately high. The prognosis relies heavily on early stage detection, with a significant disparity in survival rates between stage I and stage IV patients. Studies exploring insulin resistance (IR) as a potential risk factor for malignant melanoma are scarce. The present study therefore investigated the association between the triglyceride glucose (TyG) index, an indicator of IR, and malignant melanoma incidence. Retrospective data from patients diagnosed with malignant melanoma at the First Affiliated Hospital of Nanjing Medical University (Nanjing, China) between January 2019 and January 2024 were collected. Basic information, including age, sex and body mass index, and hematological test results, such as those for fasting triglycerides and fasting blood glucose, were analyzed. Logistic regression analysis and receiver operating characteristic (ROC) curve analysis were employed to explore the association between melanoma risk and the TyG index. A total of 403 participants, including 272 patients with malignant melanomas and 131 patients with nevi, were included in the study. The melanoma group exhibited significantly higher levels of the TyG index compared with the control group (P<0.001). Univariate and multivariable logistic regression analyses revealed the TyG index as an independent risk factor for melanoma incidence (OR, 6.33; 95% CI, 3.56-11.27; P<0.001). Incidence rates of melanoma significantly increased across tertiles of the TyG index (P<0.001). The ROC curve analysis identified a clinically acceptable predictive cutoff point for the TyG index. The present study therefore provides evidence that the TyG index is a significant risk factor for the incidence of malignant melanoma. The findings underscore the potential utility of the TyG index as a biomarker for diagnosing melanoma and suggest new avenues for melanoma treatment strategies.

Identification of key genes in periodontitis

Periodontitis, a prevalent global oral health issue, is primarily characterized by chronic inflammation resulting from bacterial infection. Periodontitis primarily affects the tissues surrounding and supporting the teeth, encompassing the gingival tissue, periodontal attachment apparatus, and the bony socket. The disease mechanism results from intricate interactions between hereditary factors, the body's defense mechanisms, and shifts in the composition of oral microbiota, with each element playing a crucial role in the initiation and advancement of the pathological process. The early symptoms of periodontitis are often not obvious, resulting in patients often not seeking medical attention until they are seriously ill, so finding biomarkers for periodontitis is essential for timely diagnosis and treatment. In this study, we selected two datasets (GSE10334 and GSE16134) by in-depth analysis of publicly available sequencing data of affected and unaffected gum tissue in periodontitis patients in the GEO database. To identify key genes associated with periodontitis pathogenesis and explore potential therapeutic biomarkers, we employed two complementary computational approaches: Random Forest, a robust machine learning algorithm for feature selection, and Weighted Gene Co-expression Network Analysis (WGCNA), a systems biology method for identifying co-expressed gene modules. Through comprehensive analysis of these combined datasets, our objective is to elucidate the underlying molecular pathways governing periodontal disease progression, thereby identifying novel therapeutic targets that may facilitate the design of improved clinical interventions for this condition. This study establishes a substantial scientific foundation that contributes to both clinical applications and fundamental research in periodontitis. The findings not only offer valuable insights for developing early diagnostic strategies and therapeutic interventions but also provide a robust theoretical framework to guide future investigations into the molecular mechanisms underlying this complex disease.

The Multifaceted Role of Endothelial Sirt1 in Vascular Aging: An Update

NAD+-dependent deacetylase sirtuin-1 (Sirt1) belongs to the sirtuins family, known to be longevity regulators, and exerts a key role in the prevention of vascular aging. By aging, the expression levels of Sirt1 decline with a severe impact on vascular function, such as the rise of endothelial dysfunction, which in turn promotes the development of cardiovascular diseases. In this context, the impact of Sirt1 activity in preventing endothelial senescence is particularly important. Given the key role of Sirt1 in counteracting endothelial senescence, great efforts have been made to deepen the knowledge about the intricate cross-talks and interactions of Sirt1 with other molecules, in order to set up possible strategies to boost Sirt1 activity to prevent or treat vascular aging. The aim of this review is to provide a proper background on the regulation and function of Sirt1 in the vascular endothelium and to discuss the recent advances regarding the therapeutic strategies of targeting Sirt1 to counteract vascular aging.

Determinants of resistance and response to melanoma therapy

Metastatic melanoma is among the most enigmatic advanced cancers to clinically manage despite immense progress in the way of available therapeutic options and historic decreases in the melanoma mortality rate. Most patients with metastatic melanoma treated with modern targeted therapies (for example, BRAFV600E/K inhibitors) and/or immune checkpoint blockade (for example, anti-programmed death 1 therapy) will progress, owing to profound tumor cell plasticity fueled by genetic and nongenetic mechanisms and dichotomous host microenvironmental influences. Here we discuss the determinants of tumor heterogeneity, mechanisms of therapy resistance and effective therapy regimens that hold curative promise.

The Effect of Body Mass Index on Melanoma Biology, Immunotherapy Efficacy, and Clinical Outcomes: A Narrative Review

Recent studies indicate that a higher body mass index (BMI) might correlate with improved responses to melanoma treatment, especially with immune checkpoint inhibitors (ICIs), despite the general association of obesity with an increased risk of cancer and higher mortality rates. This review examines the paradoxical relationship between BMI and clinical outcomes in melanoma patients by exploring molecular links, the efficacy of immunotherapy, and patient survival outcomes. Our comprehensive literature search across the PubMed and Embase databases revealed a consistent pattern: increased BMI is associated with a better prognosis in melanoma patients undergoing ICI treatment. This "obesity paradox" might be explained by the metabolic and immunological changes in obesity, which could enhance the effectiveness of immunotherapy in treating melanoma. The findings highlight the complexity of the interactions between obesity and melanoma, suggesting that adipose tissue may modulate the immune response and treatment sensitivity favorably. Our review highlights the need for personalized treatment strategies that consider the metabolic profiles of patients and calls for further research to validate BMI as a prognostic factor in clinical settings. This nuanced approach to the obesity paradox in melanoma could significantly impact treatment planning and patient management.

Alterations in Plasma Lipid Profiles Associated with Melanoma and Therapy Resistance

Dysfunctions of lipid metabolism are associated with tumor progression and treatment resistance of cutaneous melanoma. BRAF/MEK inhibitor resistance is linked to alterations of melanoma lipid pathways. We evaluated whether a specific lipid pattern characterizes plasma from melanoma patients and their response to therapy. Plasma samples from patients and controls were analyzed for FASN and DHCR24 levels and lipidomic profiles. FASN and DHCR24 expression resulted in association with disease condition and related to plasma cholesterol and triglycerides in patients at different disease stages (n = 144) as compared to controls (n = 115). Untargeted lipidomics in plasma (n = 40) from advanced disease patients and controls revealed altered levels of different lipids, including fatty acid derivatives and sphingolipids. Targeted lipidomics identified higher levels of dihydroceramides, ceramides, sphingomyelins, ganglioside GM3, sphingosine, sphingosine-1-phosphate, and dihydrosphingosine, saturated and unsaturated fatty acids. When melanoma patients were stratified based on a long/short-term clinical response to kinase inhibitors, differences in plasma levels were shown for saturated fatty acids (FA 16:0, FA18:0) and oleic acid (FA18:1). Our results associated altered levels of selected lipid species in plasma of melanoma patients with a more favorable prognosis. Although obtained in a small cohort, these results pave the way to lipidomic profiling for melanoma patient stratification.