p300 KAT regulates SOX10 stability and function in human melanoma.

SOX10 is a lineage-specific transcription factor critical for melanoma tumor growth, while SOX10 loss-of-function drives the emergence of therapy-resistant, invasive melanoma phenotypes. A major challenge has been developing therapeutic strategies targeting SOX10's role in melanoma proliferation, while preventing a concomitant increase in tumor cell invasion. Here, we report that the lysine acetyltransferase (KAT) EP300 and SOX10 gene loci on Chromosome 22 are frequently co-amplified in melanomas, including UV-associated and acral tumors. We further show that p300 KAT activity mediates SOX10 protein stability and that the p300 inhibitor, A-485, downregulates SOX10 protein levels in melanoma cells via proteasome-mediated degradation. Additionally, A-485 potently inhibits proliferation of SOX10+ melanoma cells while decreasing invasion in AXLhigh/MITFlow melanoma cells through downregulation of metastasis-related genes. We conclude that the SOX10/p300 axis is critical to melanoma growth and invasion, and that inhibition of p300 KAT activity through A-485 may be a worthwhile therapeutic approach for SOX10-reliant tumors.

Assessment of lipid and pigment content in suspicious melanocytic lesions to improve melanoma detection.

Melanoma is a highly aggressive form of skin cancer and the most frequent lethal malignancy diagnosed by dermatologists. Although there have been advances for predicting melanoma prognosis, there are few highly sensitive and specific diagnostic tools for clinically evaluating suspicious melanocytic lesions prior to biopsy. We have recently determined that alterations in cellular lipid and pigment content are associated with tumor progression and melanoma metastasis. Here, we seek to determine if lipid droplet and pigment content assessments near the skin's surface are able to distinguish benign from malignant melanocytic lesions. We obtained 14 benign melanocytic lesions, classified as Melanocytic Pathology Assessment Tool and Hierarchy for Diagnosis (MPATH-Dx) class 1, and 22 malignant melanomas, classified as MPATH-Dx class 4 or 5, from Boston Medical Center. The malignant melanomas had an average greatest thickness of 1.8 ±â€…2.1 mm with 7/22 biopsies showing the presence of ulceration. Tissues were stained with the Fontana Masson stain to detect pigment or immunohistochemically stained for adipophilin, the main protein component of lipid droplets, to detect lipid droplets. Pigment and lipid droplets were quantified using ImageJ and CellProfiler, respectively. We found no significant difference in total pigment area between benign melanocytic lesions and malignant melanoma, and a 66% decrease in lipid content and 68% reduction in lipid/pigment content between benign melanocytic lesions and malignant melanoma ( P  < 0.05). Our results suggest that lipid content and lipid/pigment content ratios may distinguish benign and malignant melanocytic lesions, which may be useful as a diagnostic tool for histopathologically challenging pigmented lesions.

Epigenetic Dysregulation in Autoimmune and Inflammatory Skin Diseases.

Epigenetics is the study of heritable, reversible gene expression patterns that do not originate from alterations in the DNA sequence. Epigenetic modifications influence gene expression patterns and include DNA methylation, histone modifications, and gene regulation via non-coding RNAs. While the study of epigenetics has been most broadly applied to neoplastic diseases, the role of the epigenome in a wide range of disease processes including autoimmune, allergic, and inflammatory processes is increasingly being recognized. Recent advances in the study of the epigenome have led to novel insights into the pathogenesis and potential therapeutic targets of various pathologic entities including inflammatory diseases. In this review, we examine the nature of epigenetic modifications in several well-studied autoimmune, allergic, and/or inflammatory disorders of the skin including systemic lupus erythematosus, vitiligo, systemic sclerosis, alopecia areata, pemphigus, psoriasis, atopic dermatitis, keloidal scarring, and hidradenitis suppurativa with the aim to determine how such epigenetic changes may be targeted for therapeutic benefit.

Eruptions and related clinical course among 296 hospitalized adults with confirmed COVID-19.

BACKGROUND: Limited information exists on mucocutaneous disease and its relation to course of COVID-19. OBJECTIVE: To estimate prevalence of mucocutaneous findings, characterize morphologic patterns, and describe relationship to course in hospitalized adults with COVID-19. METHODS: Prospective cohort study at 2 tertiary hospitals (Northwell Health) between May 11, 2020 and June 15, 2020. RESULTS: Among 296 hospitalized adults with COVID-19, 35 (11.8%) had at least 1 disease-related eruption. Patterns included ulcer (13/35, 37.1%), purpura (9/35, 25.7%), necrosis (5/35, 14.3%), nonspecific erythema (4/35, 11.4%), morbilliform eruption (4/35, 11.4%), pernio-like lesions (4/35, 11.4%), and vesicles (1/35, 2.9%). Patterns also showed anatomic site specificity. A greater proportion of patients with mucocutaneous findings used mechanical ventilation (61% vs 30%), used vasopressors (77% vs 33%), initiated dialysis (31% vs 9%), had thrombosis (17% vs 11%), and had in-hospital mortality (34% vs 12%) compared with those without mucocutaneous findings. Patients with mucocutaneous disease were more likely to use mechanical ventilation (adjusted prevalence ratio, 1.98; 95% confidence interval, 1.37-2.86); P < .001). Differences for other outcomes were attenuated after covariate adjustment and did not reach statistical significance. LIMITATIONS: Skin biopsies were not performed. CONCLUSIONS: Distinct mucocutaneous patterns were identified in hospitalized adults with COVID-19. Mucocutaneous disease may be linked to more severe clinical course.