ALDH1A3 is epigenetically regulated during melanocyte transformation and is a target for melanoma treatment

Despite the promising targeted and immune-based interventions in melanoma treatment, long-lasting responses are limited. Melanoma cells present an aberrant redox state that leads to the production of toxic aldehydes that must be converted into less reactive molecules. Targeting the detoxification machinery constitutes a novel therapeutic avenue for melanoma. Here, using 56 cell lines representing nine different tumor types, we demonstrate that melanoma cells exhibit a strong correlation between reactive oxygen species amounts and aldehyde dehydrogenase 1 (ALDH1) activity. We found that ALDH1A3 is upregulated by epigenetic mechanisms in melanoma cells compared with normal melanocytes. Furthermore, it is highly expressed in a large percentage of human nevi and melanomas during melanocyte transformation, which is consistent with the data from the TCGA, CCLE and protein atlas databases. Melanoma treatment with the novel irreversible isoform-specific ALDH1 inhibitor [4-dimethylamino-4-methyl-pent-2-ynthioic acid-S methylester] di-methyl-ampal-thio-ester (DIMATE) or depletion of ALDH1A1 and/or ALDH1A3, promoted the accumulation of apoptogenic aldehydes leading to apoptosis and tumor growth inhibition in immunocompetent, immunosuppressed and patient-derived xenograft mouse models. Interestingly, DIMATE also targeted the slow cycling label-retaining tumor cell population containing the tumorigenic and chemoresistant cells. Our findings suggest that aldehyde detoxification is relevant metabolic mechanism in melanoma cells, which can be used as a novel approach for melanoma treatment.

Angiolymphoid hyperplasia with eosinophilia affecting the oral mucosa: report of a case and a review of the literature

Angiolymphoid hyperplasia with eosinophilia (ALHE) is an uncommon disorder of unknown aetiology. Clinically, it is characterized by cutaneous papules or nodules on the head and neck, and extracutaneous involvement is rare. We report a 30-year-old woman who had an asymptomatic submucosal nodule on the upper lip, which histopathologically showed features of ALHE, and review the previously described 15 cases of oral ALHE.

Early skin metastasis of endometrial adenocarcinoma: case report and review of the literature

A seventy-seven-year-old patient presented with skin metastasis from endometrial adenocarcinoma in a laparotomy scar, seven months after surgery. On reviewing current literature, it was clear that this was an unusual site for metastasis. We review the possible pathologic mechanism of this recurrence, its prognosis, and treatment.