A Case of Psoriasis Complicated by Breast Cancer after Systemic Treatments Including Biologics.

Psoriasis is a common chronic inflammatory skin disorder that is characterized by scaly, erythematous, sharply demarcated plaques. The treatment for psoriasis has dramatically changed over the last 10 years with the introduction of biologics. However, the risk of cancer induced by biologics for psoriasis has not been fully analyzed, since these agents have such a short history of use. Here we report the case of a 74-year-old woman with psoriasis vulgaris and psoriatic arthritis complicated by breast cancer after systemic treatments including etretinate, cyclosporine, methotrexate, adalimumab, and ustekinumab.

Analysis of All 34 Exons of the SPINK5 Gene in Japanese Atopic Dermatitis Patients.

Lympho-epithelial Kazal-type-related inhibitor (LEKTI) is a large multidomain serine protease inhibitor that is expressed in epidermal keratinocytes. Nonsense mutations of the SPINK5 gene, which codes for LEKTI, cause Netherton syndrome, which is characterized by hair abnormality, ichthyosis, and atopy. A single nucleotide polymorphism (SNP) of SPINK5, p.K420E, is reported to be associated with the pathogenesis of atopic dermatitis (AD). We studied all 34 exons of the SPINK5 gene in Japanese 57 AD patients and 50 normal healthy controls. We detected nine nonsynonymous variants, including p.K420E; these variants had already been registered in the SNP database. Among them, p.R654H (n=1) was found as a heterozygous mutation in the AD patients, but not in the control. No new mutation was detected. We next compared the data of the AD patients with data from the Human Genetic Variation Database provided by Kyoto University; a significant difference was found in the frequency of the p.S368N genotype distribution. PolyPhen-2 and SIFT, two algorithms for predicting the functional effects of amino acid substitutions, showed significant scores for p.R654H. Therefore, R654H might be a risk factor for epidermal barrier dysfunction in some Japanese AD patients.

TNF-α and IL-17A induce the expression of lympho-epithelial Kazal-type inhibitor in epidermal keratinocytes.

BACKGROUND: Serine proteases have important roles in skin barrier function and desquamation, and the aberrant expression or the dysfunction of serine proteases is associated with the pathogenesis of skin diseases. Serine protease activities are tightly regulated by serine proteases such as kallikrein-related peptidases (KLKs) and serine protease inhibitors such as lympho-epithelial Kazal-type related inhibitor (LEKTI). For a better understating of diseases' pathogenesis, the regulation mechanism of serine proteases and the inhibitors' expression in epidermal keratinocytes must be clarified. OBJECTIVES: To investigate the effects of the cytokines on the expression of LEKTI in epidermal keratinocytes. METHODS: Normal human epidermal keratinocytes (NHEKs) were stimulated with panels of inflammatory cytokines. The expression of serine protease inhibitors was analyzed using quantitative real-time PCR and ELISA. LEKTI expression in normal human skin and lesions from psoriasis or atopic dermatitis (AD) were analyzed by immunohistochemically and tape-stripping. Trypsin- and chymotrypsin-like serine protease activities in culture supernatants were measured by using specific substrates. RESULTS: TNF-α and IL-17A significantly induced the expression of LEKTI in NHEKs. The immunohistochemical and tape-stripping analysis revealed that psoriatic skin lesions had higher LEKTI expression compared to normal skin and AD lesions. Trypsin- and chymotrypsin-like protease activities in the culture media were upregulated 3-5 days later but attenuated 6-7 days later period by these cytokines. CONCLUSIONS: In epidermal keratinocytes, the Th1&Th17 cytokines TNF-α and IL-17A induce the expression of serine protease inhibitor LEKTI, and it might occur to suppress the increase in the serine protease activities under inflammation.

Toll-like receptor signaling induces the expression of lympho-epithelial Kazal-type inhibitor in epidermal keratinocytes.

BACKGROUND: Lympho-epithelial Kazal-type inhibitor (LEKTI) tightly controls the activities of serine proteases such as kallikrein-related peptidase (KLK) 5 and KLK7 in the epidermis. LEKTI is known to be an essential molecule for the epidermal skin barrier, as demonstrated by SPINK5 nonsense mutation, which results in Netherton syndrome. Toll-like receptors (TLRs) recognize pathogen-associated molecular patterns or damage-associated molecular patterns and produce inflammatory cytokines, chemokines, and antimicrobial peptides. However, the effect of TLR signaling on the expression of LEKTI is not clear. OBJECTIVE: To investigate whether TLR signaling can affect expression of LEKTI in epidermal keratinocytes. METHODS: We stimulated a panel of TLR ligands and investigated the expression of LEKTI in normal human epidermal keratinocytes (NHEKs). We further measured trypsin or chymotrypsin-like serine protease activity in NHEK cultured media under stimulation with TLR3 ligand, poly (I:C). Immunostaining for LEKTI was performed using skin samples from skin infectious diseases. RESULTS: TLR1/2, 3, 5, and 2/6 ligands induced the expression of LEKTI in NHEKs. The trypsin or chymotrypsin-like serine protease activity in NHEKs was up-regulated with the stimulation of poly (I:C). The gene expressions of KLK6, KLK10, KLK11, and KLK13 were also increased by poly (I:C). An immunohistochemical analysis demonstrated that the expression of LEKTI was up-regulated in the lesions of varicella, pyoderma, and rosacea. CONCLUSIONS: TLR signaling induces the expression of LEKTI in epidermal keratinocytes, which might contribute to the control of aberrant serine protease activities in inflammatory skin diseases.