Pathogenic variants in genes that cause dilated cardiomyopathy (DCM) and arrhythmogenic cardiomyopathy (ACM) convey high risks for the development of heart failure through unknown mechanisms. Using single-nucleus RNA sequencing, we characterized the transcriptome of 880,000 nuclei from 18 control and 61 failing, nonischemic human hearts with pathogenic variants in DCM and ACM genes or idiopathic disease. We performed genotype-stratified analyses of the ventricular cell lineages and transcriptional states. The resultant DCM and ACM ventricular cell atlas demonstrated distinct right and left ventricular responses, highlighting genotype-associated pathways, intercellular interactions, and differential gene expression at single-cell resolution. Together, these data illuminate both shared and distinct cellular and molecular architectures of human heart failure and suggest candidate therapeutic targets.

Introduction: Acral lentiginous melanoma (ALM), a rare subtype, accounts for 2–3% of melanoma cases, primarily affecting the palms, soles, and nail beds and disproportionately affects people of color. This review focuses on clinical insights into ALM and its management, with a focus on race and ethnicity. Methods: A comprehensive literature search was conducted in public databases using the search term “acral melanoma,” and studies focusing on epidemiology, clinical presentation, and treatment outcomes of ALM in various racial and ethnic groups were reviewed. Results: Significant disparities in ALM outcomes exist across racial and ethnic groups, with African, Hispanic, and Asian individuals presenting with thicker, more advanced tumors at diagnosis. These populations encounter unique challenges, including limited access to dermatologic care, under-recognition of melanoma presentation in darker skin types, and socioeconomic barriers leading to delayed diagnosis and treatment. Surgical management may require specialized approaches, such as partial amputation for subungual melanomas. Additionally, there is uncertainty regarding the tumor immune microenvironment (TME) in ALM, with some studies suggesting that it might be less favorable, resulting in a lower response to immunotherapy. Conclusions: ALM affects diverse populations, and the impact of ethnic and racial origin on ALM biology is largely unknown. Addressing disparities in ALM outcomes among racial and ethnic groups is critical for improving patient care. Increased awareness of melanoma risk in individuals with darker skin can significantly impact early detection and treatment. Future research should focus on the genetic and biological factors contributing to morbidity and mortality in ALM patients.

In the published publication [...].