Pyoderma gangrenosum and impact on quality of life: A narrative review.

Pyoderma gangrenosum (PG) is an autoinflammatory disorder typically characterized by progressive ulcers with dense neutrophilic infiltrates in the absence of infectious causes. The chronic nature of this disease significantly impacts the patients' quality of life (QoL). Yet there is currently a dearth of information in the literature regarding standardised treatment guidelines and the impact of PG on patients' QoL. We conducted a literature search on PubMed using the terms "pyoderma gangrenosum" AND "quality of life." We identified nine relevant articles that provide insight into which domains are affected and what treatment can improve QoL. The most common domains involved are physical, emotional, and psychological. Patients tend to feel depressed/anxious, isolated, and embarrassed secondary to PG manifestations. Comorbidities such as Crohn's disease, monoclonal gammopathy of dermatologic significance, and ulcerative colitis can worsen the impact on these patients' QoL. Pain is also a significant contributor to decreasing patients' QoL. Treatments such as topical steroids, adalimumab, and canakinumab may help improve QoL scores. We believe this information can help clinicians guide the care of patients with PG and highlight the need for more studies and clinical trials focusing on PG treatments' impact on QoL.

GABA Regulates Electrical Activity and Tumor Initiation in Melanoma.

Oncogenes can initiate tumors only in certain cellular contexts, which is referred to as oncogenic competence. In melanoma, whether cells in the microenvironment can endow such competence remains unclear. Using a combination of zebrafish transgenesis coupled with human tissues, we demonstrate that GABAergic signaling between keratinocytes and melanocytes promotes melanoma initiation by BRAFV600E. GABA is synthesized in melanoma cells, which then acts on GABA-A receptors in keratinocytes. Electron microscopy demonstrates specialized cell-cell junctions between keratinocytes and melanoma cells, and multielectrode array analysis shows that GABA acts to inhibit electrical activity in melanoma/keratinocyte cocultures. Genetic and pharmacologic perturbation of GABA synthesis abrogates melanoma initiation in vivo. These data suggest that GABAergic signaling across the skin microenvironment regulates the ability of oncogenes to initiate melanoma. SIGNIFICANCE: This study shows evidence of GABA-mediated regulation of electrical activity between melanoma cells and keratinocytes, providing a new mechanism by which the microenvironment promotes tumor initiation. This provides insights into the role of the skin microenvironment in early melanomas while identifying GABA as a potential therapeutic target in melanoma. See related commentary by Ceol, p. 2128. This article is featured in Selected Articles from This Issue, p. 2109.