UV-Mediated Gene Expression
Yang et al. identified potential genes that participate in the melanocytic response to ultraviolet radiation (UVR). Using primary melanocyte cultures to assess for alterations in over 47,000 transcripts, they identified the 100 most statistically robust changes in transcript level; 84 genes were suppressed, and 99 genes were induced, more than twofold by UVR. About half the genes were novel transcripts. Further analysis showed that a group of select p53 target genes were also consistently elevated by UVR. The specific identity of these genes generates new avenues for investigation in the UVR biology of melanocytes and possibly melanoma tumorigenesis. See page 2490
Harlequin Gene Unmasked
Thomas et al. have shown previously that mutations in the ABCA12 gene, encoding an ATP-binding cassette (ABC) transporter, underlie the skin disease harlequin ichthyosis (HI). A multinational team of investigators has now sequenced the ABCA12 gene in an additional 14 patients. All show the mutations; the majority are either nonsense substitution or frameshift mutations. Eleven HI patients had biallelic ABCA12, and in the other three patients, ABCA12 mutations were detected on only one allele. These mutation data firmly establish ABCA12 as the major HI gene. See page 2408
Measles Kills CTCL
Measles virus (MV) has shown promise as an oncolytic virus in the treatment of tumor models including cutaneous T-cell lymphoma (CTCL). Künzi and colleagues investigated the effect of a recombinant MV (rMV) vaccine strain in CTCL cell cultures and in vivo in CTCL xenografts in nude mice. In those mice, intratumoral injection of rMV induced complete regression of large established human CTCL tumors, whereas control-treated tumors progressed exponentially. Analysis of tumor biopsies after intratumoral treatment demonstrated replication of MV within the tumors. MV appears to have potential as a therapeutic agent against CTCL. See page 2525
Psoriatic Plaque Phenotype (PPP)
The 500 participants in the Utah Psoriasis Initiative self-assessed plaque thickness when their disease was at its worst. Preliminary evidence showed that plaque thickness is an easily measured trait linked with other clinical features of psoriasis: thick plaques are associated with male gender, increased body mass index, nail disease, psoriatic arthritis, larger plaques, more body sites and greater total body surface area affected. Thin plaques are associated with eczema, guttate psoriasis, and skin cancer. Christensen and colleagues suggest that stratification on this phenotype may be useful in further defining the genetic basis of psoriasis. See page 2397
It's the Fetus, Not the Mother
Pittman and colleagues used several molecular genetic techniques to explore whether hemangioma endothelial cells (HECs) were maternal in origin. Their analyses revealed that in seven informative mother–child pairs, HECs matched the genotype of the child. In an enriched cell population, again only the genotype of the child was exhibited. The authors concluded that the phenotype is not due to any maternal component represented in the tumor, and therefore the clonal expansion of endothelial cells in the tumor stems from the fetus. See page 2533
