梅垣 知子
   Department   School of Medicine(Tokyo Women's Medical University Adachi Medical Center), School of Medicine
   Position   Associate Professor
Article types Original article
Language English
Peer review Peer reviewed
Title Clonal Expansion of Second-Hit Cells with Somatic Recombinations or C>T Transitions Form Porokeratosis in MVD or MVK Mutant Heterozygotes.
Journal Formal name:The Journal of investigative dermatology
Abbreviation:J Invest Dermatol
ISSN code:15231747/0022202X
Domestic / ForeginForegin
Volume, Issue, Page 139(12),pp.2458-2466.e9
Author and coauthor Kubo Akiharu, Sasaki Takashi, Suzuki Hisato, Shiohama Aiko, Aoki Satomi, Sato Showbu, Fujita Harumi, Ono Noriko, Umegaki-Arao Noriko, Kawai Tomoko, Nakabayashi Kazuhiko, Hata Kenichiro, Yamada Daisuke, Matsubara Yoichi, Kosaki Kenjiro, Amagai Masayuki
Publication date 2019/12
Summary Patients with disseminated superficial actinic porokeratosis (DSAP) and linear porokeratosis (LP) exhibit monoallelic germline mutations in genes encoding mevalonate pathway enzymes, such as MVD or MVK. Here, we showed that each skin lesion of DSAP exhibited an individual second hit genetic change in the wild-type allele of the corresponding gene specifically in the epidermis, indicating that a postnatal second hit triggering biallelic deficiency of the gene is required for porokeratosis to develop. Most skin lesions exhibited one of two principal second hits, either somatic homologous recombinations rendering the monoallelic mutation biallelic or C>T transition mutations in the wild-type allele. The second hits differed among DSAP lesions but were identical in those of congenital LP, suggesting that DSAP is attributable to sporadic postnatal second hits and congenital LP to a single second hit in the embryonic period. In the characteristic annular skin lesions of DSAP, the central epidermis featured mostly second hit keratinocytes, and that of the annular ring featured a mixture of such cells and naïve keratinocytes, implying that each lesion reflects the clonal expansion of single second hit keratinocytes. DSAP is therefore a benign intraepidermal neoplasia, which can be included in the genetic tumor disorders explicable by Knudson's two-hit hypothesis.
DOI 10.1016/j.jid.2019.05.020
PMID 31207227