Pruritic and antipruritic colors: An exploratory pilot study.

Itch is the commonest skin-related symptom and can be influenced by visual cues as exemplified by the phenomenon of "contagious itch." Colors are visual cues able to modify somatosensory inputs. We explored the relationship of colors and itch and the impact of color viewing on itch intensity. In this cross-sectional study, patients suffering from itch with a mean intensity of ≥2 on a Numerical Rating Scale during the last 7 days were evaluated. The study consisted of a questionnaire-based part using The Manchester Color Wheel and the ItchyQoL, followed by an interventional part. All 72 itch patients were able to match their itchy sensation with a color: In 68 patients (94.4%) this "pruritic" basic color was red. Likewise, all patients were able to define a subjective "antipruritic" color: The leading basic color choice was blue (31/72, 43.0%) followed by green (21/72, 29.1%), yellow (7/72,9.7%) and others. The impairment of the itch-related quality of life (as measured by the ItchyQoL) correlated with the brightness and saturation of the pruritic and antipruritic colors. Ten patients were visually exposed to their subjective antipruritic and pruritic color during 10 minutes resulting in a significant decrease and increase of itch intensity compared to baseline (5.1 ± 1.52 vs. 2.8 ± 1.47 [0-10 Numerical Rating Scale, NRS], p=0.0004 and 4.9 ± 1.66 vs. 6.8± 2.09 NRS, p=0.0009). These results indicate that itch can be modified by color viewing and colors matter when treating itch patients. However, further investigations are required to elucidate the therapeutic potential of colors in itch patients.

Arginine- but not alanine-rich carboxy-termini trigger nuclear translocation of mutant keratin 10 in ichthyosis with confetti.

Ichthyosis with confetti (IWC) is a genodermatosis associated with dominant-negative variants in keratin 10 (KRT10) or keratin 1 (KRT1). These frameshift variants result in extended aberrant proteins, localized to the nucleus rather than the cytoplasm. This mislocalization is thought to occur as a result of the altered carboxy (C)-terminus, from poly-glycine to either a poly-arginine or -alanine tail. Previous studies on the type of C-terminus and subcellular localization of the respective mutant protein are divergent. In order to fully elucidate the pathomechanism of IWC, a greater understanding is critical. This study aimed to establish the consequences for localization and intermediate filament formation of altered keratin 10 (K10) C-termini. To achieve this, plasmids expressing distinct KRT10 variants were generated. Sequences encoded all possible reading frames of the K10 C-terminus as well as a nonsense variant. A keratinocyte line was transfected with these plasmids. Additionally, gene editing was utilized to introduce frameshift variants in exon 6 and exon 7 at the endogenous KRT10 locus. Cellular localization of aberrant K10 was observed via immunofluorescence using various antibodies. In each setting, immunofluorescence analysis demonstrated aberrant nuclear localization of K10 featuring an arginine-rich C-terminus. However, this was not observed with K10 featuring an alanine-rich C-terminus. Instead, the protein displayed cytoplasmic localization, consistent with wild-type and truncated forms of K10. This study demonstrates that, of the various 3' frameshift variants of KRT10, exclusively arginine-rich C-termini lead to nuclear localization of K10.

Smoking does not Alter the Therapy Response to Systemic Anti-psoriatic Therapies: A Two-country, Multi-centre, Prospective, Non-interventional Study.

Psoriasis can involve the skin, joints, nails and cardiovascular system and result in a significant impairment in quality of life. Studies have shown a lower response rate to systemic anti-psoriatic therapies in smokers, and smoking is a trigger factor for psoriasis. The aim of this study was therefore to analyse the response to systemic therapies for psoriasis, with a focus on smoking. Prospectively collected data from patients with moderate to severe psoriasis included in the national psoriasis registries for Germany and Switzerland (PsoBest and SDNTT) were analysed. Therapy response was defined as reaching a Psoriasis Area and Severity Index (PASI) reduction of 75%, PASI ≤ 3 or Dermatology Life Quality Index (DLQI) ≤ 1. Out of 5,346 patients included in these registries, 1,264 met the inclusion criteria for this study. In the smoking group, 715 (60.6%) reached therapy response at month 3, compared with 358 (63.7%) in the non-smoking group (p ≤ 0.269), 659 (74.1%) vs. 330 (77%) reached therapy response at month 6 (p ≤ 0.097), and 504 (76.6%) vs. 272 (79.0%) at month 12 (p ≤ 0.611). Therefore, these data do not show that smoking affects the response rate of anti-psoriatic therapy after 3, 6 and 12 months.

Risk of Cutaneous Squamous Cell Carcinoma Development in Renal Transplant Recipients Is Independent of TMC/EVER Alterations.

BACKGROUND: Renal transplant recipients (RTRs) have an increased risk of developing nonmelanoma skin cancer, mainly cutaneous squamous cell carcinoma (cSCC). Two genes (TMC6/EVER1 and TMC8/EVER2), mutated in epidermodysplasia verruciformis (EV) patients with an increased risk of cSCC development, contain numerous single-nucleotide polymorphisms (SNPs). AIM: To evaluate the effect of SNPs in both TMC/EVER genes on the different susceptibilities of RTRs to cSCC. METHOD: We determined the occurrence of cSCC in 105 RTRs who were transplanted at least 7 years previously and investigated the frequency of 26 SNPs within both TMC/EVER genes in severely affected (n = 16) as well as in nonaffected RTRs (n = 25). RESULTS: Our data did not indicate a significant association between any SNP genotype and risk of cSCC development in RTRs. CONCLUSION: To clarify the correlation between SNPs in both TMC genes and cSCC development in RTRs, integrated investigations of large cohorts including both RTRs and immunocompetent individuals with consideration of cSCC status, SNP genotype and human papillomavirus status might be necessary.

Etiology and pathogenesis of ectodermal dysplasias.

Ectodermal dysplasias are a large group of heterogeneous heritable conditions characterized by congenital defects of one or more ectodermal structures and their appendages. The skin and its appendages are mainly composed by ectodermal components but development initiation of appendages is orchestrated by signals of the mesoderm with the help of placodes. A complex network of signaling pathways coordinates the formation and function of ectodermal structures. In recent years much has been discovered regarding the molecular mechanisms of ectodermal embryogenesis and this facilitates a rational basis for classification of ectodermal dysplasia. Interestingly, not only complex ectodermal syndromes but also mono- or oligosymptomatic ectodermal malformations may result from a mutation in a gene that is critical for ectodermal development. Mesodermal, and occasionally endodermal malformations may coexist. Embryogenesis occurs in distinct tissue organizational fields and specific interactions among the germ layers exist that may lead to a wide range of ectodermal dysplasias. Of the approximately 200 different ectodermal dysplasias, about 80 have been characterized at the molecular level with identification of the genes that are mutated in these disorders. Modern molecular genetics will increasingly elucidate the basic defects of these distinct syndromes and shed more light into the regulatory mechanisms of embryology. The upcoming classification of ectodermal dysplasias will combine detailed clinical and molecular knowledge.

Second International Conference on a classification of ectodermal dysplasias: development of a multiaxis model.

Ectodermal dysplasias (EDs) comprise a large clinically and etiologically heterogeneous group of genetic disorders characterized by abnormalities in tissues derived from the embryonic ectoderm. Controversy exists over which syndromes should be classified as EDs and which should be excluded from the classification. The challenge will be to balance comprehensiveness within the classification with usability and accessibility so that the benefits truly serve the needs of researchers, health-care providers, and ultimately the individuals and families directly affected by EDs. The overarching goal of the Second International Conference was to develop a consensus on EDs classifications, with the ultimate goal of creating a system that integrates clinical and molecular knowledge, using an interactive Internet-based database that clinicians, researchers, and laymen can use. The Conference, brought together a group of experts from around the world, including a diverse health-care providers, researchers, patient advocate representatives, and administrators. The Conference was modeled after the 2008 conference, with plenary sessions, scientific updates, and small group discussions. Based on the present clinical knowledge, new molecular advances and both coupled with new bioinformatics developments, the participants agree to develop a multi-axis system approach for the classification of EDs. The multi-axis approach will include a clinical/phenotype axis, a gene-based axis, and a functional/pathways axis. The significance of the conference outcomes includes, a new classification approach that will foster a better understanding of EDs, open new fields of research and develop a nosologic approach that may have broad implications for classifying other hereditary conditions.

MicroRNA expression differs in cutaneous squamous cell carcinomas and healthy skin of immunocompetent individuals.

Cutaneous squamous cell carcinoma (cSCC) is one of the most common skin cancers, but the influence of microRNA (miRNA) expression has only been sporadically analysed. We hypothesized that miRNAs are differentially expressed in cSCC and hence influence its development. We therefore isolated total miRNA from well-differentiated cSCCs and from controls without SCC. Expression analyses of 12 miRNAs showed three significantly differentially expressed miRNAs. We identified a significant upregulation of the miR-21 and the miR-31, a proto-oncogene like miR-21. While the upregulated expression of miR-21 has been known for some time, the increased expression of miR-31 was never shown so clearly. Furthermore, we showed the upregulation of miRNA-205, which has never been described before. The miR-205 induces specific keratinocyte migration and could be a characteristic marker for cSCC. It has to be determined in following studies whether these upregulated expressions are specific for cSCC and if so, for which cSCC stages.

Bone overgrowth-associated mutations in the LRP4 gene impair sclerostin facilitator function.

Humans lacking sclerostin display progressive bone overgrowth due to increased bone formation. Although it is well established that sclerostin is an osteocyte-secreted bone formation inhibitor, the underlying molecular mechanisms are not fully elucidated. We identified in tandem affinity purification proteomics screens LRP4 (low density lipoprotein-related protein 4) as a sclerostin interaction partner. Biochemical assays with recombinant proteins confirmed that sclerostin LRP4 interaction is direct. Interestingly, in vitro overexpression and RNAi-mediated knockdown experiments revealed that LRP4 specifically facilitates the previously described inhibitory action of sclerostin on Wnt1/ß-catenin signaling. We found the extracellular ß-propeller structured domain of LRP4 to be required for this sclerostin facilitator activity. Immunohistochemistry demonstrated that LRP4 protein is present in human and rodent osteoblasts and osteocytes, both presumed target cells of sclerostin action. Silencing of LRP4 by lentivirus-mediated shRNA delivery blocked sclerostin inhibitory action on in vitro bone mineralization. Notably, we identified two mutations in LRP4 (R1170W and W1186S) in patients suffering from bone overgrowth. We found that these mutations impair LRP4 interaction with sclerostin and its concomitant sclerostin facilitator effect. Together these data indicate that the interaction of sclerostin with LRP4 is required to mediate the inhibitory function of sclerostin on bone formation, thus identifying a novel role for LRP4 in bone.

Prevalence of skin lesions in familial adenomatous polyposis: a marker for presymptomatic diagnosis?

BACKGROUND AND AIMS: Benign skin tumors such as lipomas, fibromas, and epidermal cysts are among the extracolonic manifestations of familial adenomatous polyposis (FAP). Readily detectable by inspection, they could serve as presymptomatic diagnostic markers to identify FAP patients. We therefore prospectively determined the prevalence of cutaneous lesions in genetically confirmed adenomatous polyposis coli (APC) mutation carriers and assessed their potential usefulness in the identification of FAP patients. METHODS: Whole-skin examination was performed in 56 adult APC mutation carriers, compared with a control group (n = 116). In addition, FAP patients were investigated for the presence of congenital hypertrophy of the retinal pigment epithelium (CHRPE), an established clinical marker for FAP, and a detailed review of medical records was performed. RESULTS: Nearly half of all FAP patients (48.2%) had at least one FAP-associated skin lesion, compared with one third (34.5%) of controls. Only multiple lipomas and combined skin lesions were significantly more prevalent in APC mutation carriers. CHRPE was observed in 22 (43.1%) of 51 FAP patients, including 14 (37.8%) of 37 individuals with APC mutations outside the CHRPE-associated region between codons 311 and 1465. CONCLUSIONS: Despite a significantly higher prevalence of multiple lipomas, occurring at younger age, and combined skin lesions in APC mutation carriers, the low diagnostic sensitivity of FAP-associated skin lesions precludes their use as markers for FAP in clinical practice. Based on our findings, the common CHRPE-associated region should be extended to APC codons 148-2043.

Homozygosity for the c.917A→T (p.N306l) polymorphism in the EVER2/TMC8 gene of two sisters with epidermodysplasia verruciformis Lewandowsky-Lutz originally described by Wilhelm Lutz.

BACKGROUND: Epidermodysplasia verruciformis Lewandowsky-Lutz (EV) is a rare genodermatosis, characterised by development of numerous verrucous skin lesions caused by specific genotypes of human papillomaviruses belonging to the ß-papillomavirus genus. The EV loci were mapped to chromosome 2p21-p24 (EV2) and 17q25 (EV1). On chromosome 17, 2 adjacent related genes--EVER1/TMC6 and EVER2/TMC8--were identified. We reinvestigated 2 patients originally described by Wilhelm Lutz in 1946 with the aim to document the natural course of the disease and confirm his diagnosis. METHODS: PCR fragments specific for exons with short flanking intron sequences of EVER1/TMC6 and EVER2/TMC8 genes from patients' DNA were amplified using sequence information. The single-nucleotide polymorphism (SNP) rs7208422 was studied, using restriction fragment length polymorphism analysis. RESULTS: In the index patient, we identified a homozygous TT genotype in exon 8 of the EVER2/TMC8 gene (c.917A→T, p.N306I). The same mutation could thereafter be detected in her sister from paraffin-embedded skin. CONCLUSION: We have followed one of the first patients described with EV in Basel, Switzerland, in 1930 until today and demonstrated the TT genotype (SNP rs7208422) in the EVER2/TMC8 gene in this index patient and her sister. The results underline the possible relevance of SNP rs7208422 by influencing the susceptibility to ß-papillomaviruses and their oncogenic potential.

Superimposed linear psoriasis unmasked by therapy with adalimumab.

Several inflammatory skin disorders with a polygenic mode of inheritance (e.g. psoriasis, atopic dermatitis, vitiligo, and lichen planus) sometimes show, by way of exception, a segmental distribution. Superimposed linear psoriasis is an exceedingly rare disorder, but it has been found in both vulgaris and pustular types. This manifestation is probably either due to postzygotic allelic loss at one of the responsible gene loci, or to a postzygotic new mutation at an additional predisposing gene locus. In our case, a unilateral Blaschko-linear distribution was unmasked after treatment of severe non-segmental psoriasis with adalimumab (Humira(R)), reflecting an increased mutational burden of the segmentally involved area.

Buschke-Ollendorff syndrome in a three-generation family: influence of a novel LEMD3 mutation to tropoelastin expression.

Buschke-Ollendorff syndrome refers to the concomitant occurrence of connective tissue nevi, composed of elastic fibers in most cases, with osteopoikilosis. This autosomal dominant inherited disorder is caused by mutations in the gene LEMD3 on chromosome 12q14, which induces a rather heterogeneous clinical phenotype. Here, we report on the most proximal germline mutation found to date in the LEMD3 gene, p.Val94fs, in a three-generation Swiss family. Quantitative RNA analyses in affected and non-affected skin tissue from the proband demonstrate a comparable nonsense-mediated decay of mutant LEMD3 mRNA in both tissues; however, different levels of tropoelastin expression suggest that additional factors are involved in the development of the cutaneous lesions.

Disorders of pigmentation.

Skin color is highly individual and the variations are controlled by numerous genes. The different skin colors result from the size and number of melanosomes and do not mirror the amount of melanocytes. Disorders of pigmentation can result from migration abnormalities of melanocytes from the neural crest to the skin during embryogenesis. In addition, impairment of melanosome transfer to the surrounding keratinocytes, an alteration in melanin synthesis and a defective degradation or removal of melanin may lead to abnormal skin pigmentation. Immunologic or toxic mediated destructions of melanocytes can end in pigmentation disorders. Disorders of pigmentation are classified in hypo- or hyperpigmentation which can occur as a genetic or acquired disease. They can manifest locally or diffuse. Congenital hypopigmentation can be restricted to the skin as in piebaldism or they represent a systemic disease as in Menkes disease or phenylketonuria. Localized hypo- or hyperpigmentation in children may serve as markers for systemic diseases. Ash-leaf hypopigmentation are characteristic for tuberous sclerosis and more than 5 café-au-lait spots suggest neurofibromatosis 1 (von Recklinghausen disease). The most common autoimmune-induced depigmentation is vitiligo. Generalized hyperpigmentation only rarely reflects a primary genetic disorder but is most often from acquired diseases as in Addison disease, secondary hemochromatosis or primary biliary cirrhosis. Treatment of pigmentation disorders are based on a diagnosis which sometimes allow a specific intervention. Cosmetically acceptable results are difficult to obtain.

[Genodermatoses for practitioners--principles and concepts]. / Genodermatosen in der täglichen Praxis - die Rolle des Dermatologen.

Every disease is a mirror of interactions between genes and the environment. In monogenic disorders only one mutation can lead to a specific phenotype. However the spectrum and the degree of manifestations depend on numerous factors from the environment. Ichthyosis vulgaris is caused by a mutation in the filaggrin gene. However the phenotype is much more pronounced in the winter months. In polygenic disorders such as atopic dermatitis numerous modifying genes influence the phenotype including a mutation in filaggrin. The skin is the organ of the human body which is most commonly involved in monogenic diseases. More than one third of all genetic diseases affect the integument. At the very moment more than 350 genodermatoses are identified with functional insights. The Human Genome Project was finished in 2001 with the aim that all genes can be identified for diagnostics, pharmacogenomics potential gene therapy and to understand the principle basis of diseases. The next project called ENCODE for Enzyclopedia of DNA Elements targets to identify all functional elements in the human genome sequence. MicroRNAs seem to have great importance for the regulation of genefunctions in the skin. At the moment epigenetics is at the epicentre of modern medicine. Epigenetics is the study of non-DNA sequence-related heredity. Epigenetics is an important tool to study the relationship between the genome and the environment. In the second part cases will be presented and the way of diagnosis making will be shown. It will be shown that it is very important to find clinical key features which may allow an allocation to a genetic pathway.

Gene expression is stable in a complete CIB1 knockout keratinocyte model.

Epidermodysplasia verruciformis (EV) is a genodermatosis characterized by the inability of keratinocytes to control cutaneous ß-HPV infection and a high risk for non-melanoma skin cancer (NMSC). Bi-allelic loss of function variants in TMC6, TMC8, and CIB1 predispose to EV. The correlation between these proteins and ß-HPV infection is unclear. Its elucidation will advance the understanding of HPV control in human keratinocytes and development of NMSC. We generated a cell culture model by CRISPR/Cas9-mediated deletion of CIB1 to study the function of CIB1 in keratinocytes. Nine CIB1 knockout and nine mock control clones were generated originating from a human keratinocyte line. We observed small changes in gene expression as a result of CIB1 knockout, which is consistent with the clearly defined phenotype of EV patients. This suggests that the function of human CIB1 in keratinocytes is limited and involves the restriction of ß-HPV. The presented model is useful to investigate CIB1 interaction with ß-HPV in future studies.

Rationale and background as basis for a new classification of the ectodermal dysplasias.

Ectodermal dysplasias are heterogeneous heritable conditions characterized by congenital defects of one or more ectodermal structures and their appendages. Of approximately 200 different ectodermal dysplasias, about 30 have been identified at molecular level with identification of the causative gene. Itin and Fistarol emphasized that rather commonly non-fully expressed phenotypes exist, which make a clinical diagnosis more difficult. Freire-Maia and Pinheiro used the clinical aspects for their classification and Priolo integrated molecular genetic and clinical aspects for her scheme. Those two more historical classification schemes have the difficulty that when applied strictly, several additional groups of disorders should be integrated within the term of ectodermal dysplasias, for example, keratodermas with skin or hair alterations or the ichthyoses with associated abnormalities. Such consequent classification would lead to an endless list of conditions and would be useless for practical work. Recent evidence implicates a genetic defect in different pathways orchestrating ectodermal organogenesis. Modern molecular genetics will increasingly elucidate the basic defects of the different syndromes and yield more insight into the regulatory mechanisms of morphogenesis. In this way a reclassification of ectodermal dysplasias will be possible according to the function of their involved mutated genes. I will focus on the fact that with molecular methods it is possible to diagnose oligosymptomatic forms of ectodermal dysplasia. This is much more common than earlier anticipated and with the classification of ectodermal dysplasia on the basis of molecular diagnosis a new avenue is opened for symptom complexes which were impossible to classify in former times.

Happle-Tinschert syndrome. Segmentally arranged basaloid follicular hamartomas, linear atrophoderma with hypo- and hyperpigmentation, enamel defects, ipsilateral hypertrichosis, and skeletal and cerebral anomalies.

Recently, Happle and Tinschert [Acta Derm Venereol 2008;88:382-387] described the case of a multisystem birth defect with segmentally arranged basaloid follicular hamartomas associated with extracutaneous defects in the form of short leg, polydactyly and hypoplastic teeth. The authors presented a comprehensive overview of 8 similar cases reported under various designations, and provided evidence that this syndrome includes various additional defects of the bones, teeth and brain. Here, a further typical case is reported, and it is emphasized that this phenotype should no longer be categorized as 'basal cell nevus syndrome', and thus be confused with the nevoid basal cell carcinoma syndrome of Gorlin [Cancer 1965;18:89-104]. A 7-year-old boy had multiple whitish and some scattered brownish basaloid follicular hamartomas involving the right side of his body in a systematized pattern following the lines of Blaschko. These lesions had been present since birth. They were hairless and conspicuously hypopigmented. In addition, enamel defects and mild webbing of the first and second right toes were noted. At the age of 5 years, the boy developed a medulloblastoma that originated from the ipsilateral paramedian vermis region. The tumor was surgically removed, and subsequently radiotherapy and chemotherapy were applied. Analysis of blood DNA did not reveal any Patched mutation. The molecular basis of the disorder remains to be elucidated. From this case and from 9 similar cases reported in the literature, the spectrum of a distinct phenotype is delineated, and the eponymic designation Happle-Tinschert syndrome is proposed.

Cetuximab therapy of metastasizing cutaneous squamous cell carcinoma in a patient with severe recessive dystrophic epidermolysis bullosa.

Dystrophic epidermolysis bullosa (EB) is a genetic skin fragility condition with propensity to skin cancer. The severest subtype is the generalized recessive dystrophic EB (RDEB), in which mechanically induced skin blisters and erosions heal with severe scarring. A common and potentially life-threatening complication in RDEB is cutaneous squamous cell carcinoma (SCC). In spite of generally good differentiation of SCC associated with RDEB (RDEB-SCC), the tumours behave in an aggressive manner and metastasize early. Despite the high prevalence of RDEB-SCC, systematic studies on therapeutic options have not been reported. Wide surgical excision is recommended, and unresectable cases have been treated with radiotherapy. Here we report the first treatment of metastasized RDEB-SCC with the epidermal growth factor receptor antagonist cetuximab (Erbitux). The response was favourable, and adverse events were similar to those in patients without EB. Notably, no additional negative cutaneous effects, such as severer skin or mucosal blistering, occurred.