Increased Cthrc1 Activates Normal Fibroblasts and Suppresses Keloid Fibroblasts by Inhibiting TGF-ß/Smad Signal Pathway and Modulating YAP Subcellular Location.

Keloid may induce severe impairment of life quality for the patients, although keloid is a cutaneous benign tumor. Collagen triple helix repeat containing protein 1 (Cthrc1) was identified as a novel gene that was originally found in adventitial fibroblasts after arterial injury. To address the role of Cthrc1 in keloid, the expression level of Cthrc1 was assessed in normal skin and keloid tissue, as well as in normal fibroblasts (NFs) and keloid fibroblasts (KFs) by using quantitative PCR, Western blotting and immunohistochemical analysis. The results showed that Cthrc1 was increased in keloid tissue and KFs as compared with normal skin and NFs. Meanwhile, CCK8 and Transwell assays found the cellular proliferation and migration of KFs were increased as compared with NFs. Further, to verify the function of Cthrc1 in NFs and KFs, we increased Cthrc1 expression by transfecting lentivirus (LV) vectors LV-Cthrc1. The cellular proliferation and migration, collagen synthesis and the influence on TGF-ß and YAP signaling were tested. The cellular proliferation and migration were increased in NFs-Cthrc1 as compared with NFs-control. Meanwhile, YAP expression and nuclear-location was increased in NFs-Cthrc1. On the contrary, when Cthrc1 was overexpressed in KFs, the cellular migration was suppressed and YAP expression was reduced and transferred to cytoplasm in KFs-Cthrc1 as compared with KFs-control. But the expression level of collagen I was decreased and pSmad2/3 nucleus transfer was suppressed in both NFs-Cthrc1 and KFs-Cthrc1 by using Western blotting and immunofluorescence. Increased Cthrc1 activated NFs by promoting YAP nucleus translocation, whereas suppressed KFs by inhibiting YAP nucleus translocation. Enhanced Cthrc1 decreased collagen I in both NFs and KFs by inhibiting TGF-ß/Smad pathway. In conclusion, Cthrc1 may play a role in the pathogenesis of keloid by inhibiting collagen synthesis and fibroblasts migration via suppressing TGF-ß/Smad pathway and YAP nucleus translocation.

Association analyses identify three susceptibility Loci for vitiligo in the Chinese Han population.

To identify susceptibility loci for vitiligo, we extended our previous vitiligo genome-wide association study with a two-staged replication study that included 6,857 cases and 12,025 controls from the Chinese Han population. We identified three susceptibility loci, 12q13.2 (rs10876864, P(combined)=8.07 × 10(-12), odds ratio (OR)=1.18), 11q23.3 (rs638893, P(combined)=2.47 × 10(-9), OR=1.22), and 10q22.1 (rs1417210, P(combined)=1.83 × 10(-8), OR=0.88), and confirmed three previously reported loci for vitiligo, 3q28 (rs9851967, P(combined)=8.57 × 10(-8), OR=0.88), 10p15.1 (rs3134883, P(combined)=1.01 × 10(-5), OR=1.11), and 22q12.3 (rs2051582, P(combined)=2.12 × 10(-5), OR=1.14), in the Chinese Han population. The most significant single-nucleotide polymorphism in the 12q13.2 locus is located immediately upstream of the promoter region of PMEL, which encodes a major melanocyte antigen and has expression loss in the vitiligo lesional skin. In addition, both 12q13.2 and 11q23.3 loci identified in this study are also associated with other autoimmune diseases such as type 1 diabetes and systemic lupus erythematosus. These findings provide indirect support that vitiligo pathogenesis involves a complex interplay between immune regulatory factors and melanocyte-specific factors. They also highlight similarities and differences in the genetic basis of vitiligo in Chinese and Caucasian populations.

Psoriasis regression analysis of MHC loci identifies shared genetic variants with vitiligo.

Psoriasis is a common inflammatory skin disease with genetic components of both immune system and the epidermis. PSOR1 locus (6q21) has been strongly associated with psoriasis; however, it is difficult to identify additional independent association due to strong linkage disequilibrium in the MHC region. We performed stepwise regression analyses of more than 3,000 SNPs in the MHC region genotyped using Human 610-Quad (Illumina) in 1,139 cases with psoriasis and 1,132 controls of Han Chinese population to search for additional independent association. With four regression models obtained, two SNPs rs9468925 in HLA-C/HLA-B and rs2858881 in HLA-DQA2 were repeatedly selected in all models, suggesting that multiple loci outside PSOR1 locus were associated with psoriasis. More importantly we find that rs9468925 in HLA-C/HLA-B is associated with both psoriasis and vitiligo, providing first important evidence that two major skin diseases share a common genetic locus in the MHC, and a basis for elucidating the molecular mechanism of skin disorders.

Olmsted syndrome: a case report and review of literature.

We report a case of an 18-month-old boy with slightly whitened fingernails and toenails since birth. At the age of 100 days, he progressively developed bilateral palmoplantar keratoderma which resulted in painful walking and disabled grasping. Perianal keratotic plaques and perioral hyperkeratotic erythema could also be observed. Both fingernails and toenails were dystrophic. Scalp hairs were sparse, but total alopecia was no present. The histopathologic changes of the biopsy from the inner side of the right foot showed nonspecific changes, which mainly showed highly hyperkeratosis and acanthosis with slight superficial perivascular inflammatory infiltration. A clinical diagnosis of Olmsted syndrome was established according to the typical feature of the lesions, which is the presence of symmetrical palmoplantar keratoderma with periorificial keratotic plaques. We review the literature and present a summary of all reported cases to date.