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Published on: September 7, 2013
[Genetic basis of seborrheic keratosis and epidermal nevi]
C Hafner1, H Hafner, L Groesser
1Dermatohistologisches Labor, Sonnenstr. 7, 80331, München, Deutschland, christian.hafner@ukr.de.
Abstract:
Seborrheic keratosis (SK) and epidermal nevi (EN) represent benign skin tumors and congenital lesions, respectively. Oncogenic mutations are fundamentally involved in their pathogenesis and SK is characterized by a broad spectrum of somatic mutations in the FGFR3, PIK3CA, RAS, AKT1 and EGFR genes. In contrast to malignant tumors, SK is genetically stable without alterations of tumor suppressor genes. The ENs are caused by postzygotic activating hot spot mutations in FGFR3, PIK3CA and particularly HRAS, resulting in a genetic mosaicism. The size of the lesions and the differentiation potential of the mutated cell into various tissue types depends on the time point of the mutation during embryogenesis. The genetic mosaic may predispose to a later growth of benign and malignant (adnexal) tumors.
Insights
Seborrheic keratosis and epidermal nevi arise from specific gene mutations. These benign skin conditions involve genetic mosaicism, potentially influencing future tumor development.
Area of Science:
- Dermatology
- Oncology
- Genetics
Context:
- Seborrheic keratosis (SK) and epidermal nevi (EN) are common benign skin growths.
- Understanding their genetic underpinnings is crucial for differentiating them from malignant conditions.
- Somatic mutations play a key role in the development of these lesions.
Purpose:
- To investigate the genetic mutations responsible for the development of seborrheic keratosis and epidermal nevi.
- To explore the role of genetic mosaicism in epidermal nevi.
- To determine if these benign conditions predispose to future tumor formation.
Summary:
- Seborrheic keratosis (SK) involves somatic mutations in genes like FGFR3, PIK3CA, RAS, AKT1, and EGFR, without tumor suppressor gene alterations.
- Epidermal nevi (EN) are caused by postzygotic mutations in FGFR3, PIK3CA, and HRAS, leading to genetic mosaicism.
- The timing of mutations during embryogenesis influences lesion size and differentiation, with potential predisposition to adnexal tumors.
Impact:
- Provides insight into the molecular pathogenesis of benign skin tumors and congenital lesions.
- Highlights the genetic stability of SK, contrasting with malignant tumors.
- Suggests a link between genetic mosaicism in EN and the potential development of future benign and malignant adnexal tumors.
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