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American Journal of Human Genetics May 2024Porokeratosis is a clonal keratinization disorder characterized by solitary, linearly arranged, or generally distributed multiple skin lesions. Previous studies showed...
Porokeratosis is a clonal keratinization disorder characterized by solitary, linearly arranged, or generally distributed multiple skin lesions. Previous studies showed that genetic alterations in MVK, PMVK, MVD, or FDPS-genes in the mevalonate pathway-cause hereditary porokeratosis, with skin lesions harboring germline and lesion-specific somatic variants on opposite alleles. Here, we identified non-hereditary porokeratosis associated with epigenetic silencing of FDFT1, another gene in the mevalonate pathway. Skin lesions of the generalized form had germline and lesion-specific somatic variants on opposite alleles in FDFT1, representing FDFT1-associated hereditary porokeratosis identified in this study. Conversely, lesions of the solitary or linearly arranged localized form had somatic bi-allelic promoter hypermethylation or mono-allelic promoter hypermethylation with somatic genetic alterations on opposite alleles in FDFT1, indicating non-hereditary porokeratosis. FDFT1 localization was uniformly diminished within the lesions, and lesion-derived keratinocytes showed cholesterol dependence for cell growth and altered expression of genes related to cell-cycle and epidermal development, confirming that lesions form by clonal expansion of FDFT1-deficient keratinocytes. In some individuals with the localized form, gene-specific promoter hypermethylation of FDFT1 was detected in morphologically normal epidermis adjacent to methylation-related lesions but not distal to these lesions, suggesting that asymptomatic somatic epigenetic mosaicism of FDFT1 predisposes certain skin areas to the disease. Finally, consistent with its genetic etiology, topical statin treatment ameliorated lesions in FDFT1-deficient porokeratosis. In conclusion, we identified bi-allelic genetic and/or epigenetic alterations of FDFT1 as a cause of porokeratosis and shed light on the pathogenesis of skin mosaicism involving clonal expansion of epigenetically altered cells.
Topics: Porokeratosis; Humans; Mosaicism; Epigenesis, Genetic; DNA Methylation; Keratinocytes; Promoter Regions, Genetic; Male; Alleles; Female
PubMed: 38653249
DOI: 10.1016/j.ajhg.2024.03.017 -
International Journal of Dermatology Apr 2024
PubMed: 38650077
DOI: 10.1111/ijd.17202 -
Journal of Cosmetic Dermatology Apr 2024
PubMed: 38597574
DOI: 10.1111/jocd.16325 -
Indian Journal of Dermatology,... Apr 2024
PubMed: 38594979
DOI: 10.25259/IJDVL_880_2023 -
The American Journal of Dermatopathology Jul 2024Spiny keratoderma is a rare entity presenting with minute keratotic spines on the palms and soles. Spiny keratoderma can be inherited or acquired, and the acquired form...
Spiny keratoderma is a rare entity presenting with minute keratotic spines on the palms and soles. Spiny keratoderma can be inherited or acquired, and the acquired form may be associated with underlying malignancy or systemic disease. Clinically, the differential diagnosis includes other digitate keratoses on acral sites, most notably arsenical keratosis, filiform verruca, and punctate porokeratosis. Biopsy findings typically include a column of parakeratosis overlying a diminished granular cell layer. In this article, we present 3 cases of acquired spiny keratoderma in patients with various systemic diseases, but no underlying malignancy.
Topics: Humans; Female; Male; Middle Aged; Keratoderma, Palmoplantar; Aged; Biopsy; Adult
PubMed: 38574081
DOI: 10.1097/DAD.0000000000002705 -
Cureus Feb 2024Porokeratosis encompasses a diverse group of dermatoses, both acquired and genetic, marked by a keratinization disorder. Porokeratosis of Mibelli (PKM) presents as...
Porokeratosis encompasses a diverse group of dermatoses, both acquired and genetic, marked by a keratinization disorder. Porokeratosis of Mibelli (PKM) presents as solitary plaques or multiple papules/macules with central atrophy and raised hyperkeratotic borders. Here, we present a case of giant porokeratosis (GPK), a rare form often considered a morphological variant of PKM, with unique clinical and histopathological aspects. Our case involves a 29-year-old patient with a 15 × 10 cm irregular plaque on the dorsal aspect of the right hand. The patient was previously prescribed various topical treatments (retinoids, calcineurin inhibitors, and combinations of corticosteroids with vitamin D3 analogs) and systemic retinoids without improvement before presenting to our department. Due to the high risk of neoplastic transformation and the unavailability of imiquimod, the patient was recommended topical 5-fluorouracil treatment. The trajectory of the lesion under treatment revealed a favorable evolution, and the patient was subjected to regular monitoring every three months to assess the ongoing progress. Recognizing GPK as a high-risk variant is crucial for dermatologists, and it requires a personalized approach. Regular monitoring is advised to detect potential malignant transformations promptly. Future research holds promise for diagnostic advancements, refined treatment modalities, and a deeper understanding of the molecular mechanisms underlying malignancy in porokeratosis.
PubMed: 38558715
DOI: 10.7759/cureus.55155 -
Nagoya Journal of Medical Science Feb 2024Whole-exome and whole-genome sequencing have become widespread in approximately the last 15 years, and the predisposing factors and pathomechanisms of inflammatory... (Review)
Review
Whole-exome and whole-genome sequencing have become widespread in approximately the last 15 years, and the predisposing factors and pathomechanisms of inflammatory keratinization diseases, which have been unknown for a long time, have gradually been revealed. Hence, various inflammatory keratinization diseases are recognized to cause innate immunity hyperactivation. Therefore, we have been advocating for the clinical entity, "autoinflammatory keratinization diseases (AiKDs)" since 2017. AiKDs are inflammatory keratinization diseases caused by autoinflammatory-related pathomechanisms in the skin. The aberrant activation of innate immunity and the resultant autoinflammation in the epidermis and the superficial dermis in AiKDs cause hyperkeratosis in the epidermis. Our initially proposed concept of AiKDs included generalized pustular psoriasis and related conditions, pityriasis rubra pilaris type V, and familial keratosis lichenoides chronica. Since then, the number of diseases known to be AiKDs has increased as previously unknown disease-causing factors and pathogenetic mechanisms of inflammatory keratinization diseases have been clarified one by one. To date, porokeratosis, hidradenitis suppurative, keratosis linearis with ichthyosis congenita and sclerosing keratoderma (KLICK) syndrome, and AiKDs associated with epidermal growth factor receptor (EGFR) deficiency or with hepatitis and autism have been recognized as AiKDs. The concept of AiKDs is considered extremely useful in our precise understanding of the pathogeneses behind inflammatory keratinization diseases and our appropriate treatment method selection. The number of AiKDs is expected to grow with the clarification of the pathomechanisms of further inflammatory keratinization diseases.
Topics: Humans; Keratosis; Skin; Skin Neoplasms; Syndrome
PubMed: 38505726
DOI: 10.18999/nagjms.86.1.1 -
Skinmed 2024
Topics: Humans; Porokeratosis; Keratosis, Actinic
PubMed: 38494616
DOI: No ID Found -
The Australasian Journal of Dermatology Jun 2024
Topics: Humans; Porokeratosis; Dermoscopy; Ultraviolet Rays; Male; Fluorescence; Female
PubMed: 38421822
DOI: 10.1111/ajd.14241