Search

Background Familial benign chronic pemphigus, also known as Hailey-Hailey disease (HHD), is a clinically rare bullous Dermatosis. However the mechanism has not been clarified. The study aim to detect novel mutations in exons of ATP2C1 gene in HHD patients; to explore the possible mechnism of HHD pathogenesis by examining the expression profile of hSPCA1, miR-203, p63, Notch1 and HKII proteins in the skin lesions of HHD patients. Methods Genomic DNA was extracted from peripheral blood of HHD patients. All exons of ATP2C1 gene in HHD patients were amplified by PCR and the products were purified and sequenced. All related signaling proteins of interest were stained by using skin lesion tissues from HHD patients and miR-203 levels were also determined. Results One synonymous mutation c.G2598A (in exon 26), one nonsense mutation c.C635A and two missense mutations c.C1286A (p.A429D) and c. A1931G (p. D644G) were identified. The nonsense mutation changed codon UCG to stop codon UAG, causing a premature polypeptide chain of the functional region A. The two missense mutations were located in the region P (phosphorylation region) and the Mn binding site of hSPCA1. The level of hSPCA1 was significantly decreased in HHD patients compared to the normal human controls, accompanied by an increase of miR-203 level and a decrease of p63 and HKII levels. Conclusion In our study, we found four mutations in HHD. Meanwhile we found increase of miR-203 level and a decrease of p63 and HKII levels. In addition, Notch1, which was negatively regulated p63, is downregulated. These factors may be involved in the signaling pathways of HHD pathogenesis. Our data showed that both p63 and miR-203 may have significant regulatory effects on Notch1 in the skin.

Psoriasis is a multifactorial, recurring, and chronic inflammatory skin disease characterized by hyperproliferation of keratinocytes. Evidence is rapidly accumulating for the role of microRNAs in psoriasis. The object of the study was to explore the functions and precise mechanism of miR-142-3p in human keratinocyte HaCaT cells in the presence of M5. Here, the results showed that miR-142-3p expression was heightened in HaCaT cells induced by M5. In addition, inhibition of miR-142-3p dramatically restricted cell proliferation and enhanced apoptosis in HaCaT cells exposed to M5, as exemplified by a decrease in the antiapoptotic Bcl-2 protein, concomitant with an increase in the proapoptotic proteins Bax. Moreover, depleting miR-142-3p effectively ameliorated M5-induced inflammation response, as reflected by the attenuation of multiple inflammatory factors. Importantly, Sema3A was identified as an authentic target of miR-142-3p, and indeed regulated by miR-142-3p. Mechanistically, silencing of Sema3A effectively abolished the anti-proliferative, apoptosis-promoting, and anti-inflammatory effects of miR-142-3p inhibition in keratinocytes. Taken together, these data elucidated that repression of miR-142-3p protect HaCaT cells against M5-induced hyper-proliferation and inflammatory injury by suppressing its target Sema3A, implying that the miR-142-3p/Sema3A axis may be a new target for preventing keratinocyte injury process. These findings provide a new and better understanding of the mediating role of miR-142-3p in psoriasis.

Psoriasis is a chronic disease which carries the emotional and social burden, promotes joint disability and raises comorbidity possibility in patients. Obesity is closely correlated with the occurrence of psoriasis and adipokines produced by adipose tissues were found to be critical culprits. Chemerin is one of them and its expression was increased in patients with psoriatic arthritis. In our hypothesis, chemerin might act on keratinocytes and promote an inflammatory response, which plays an essential role in psoriatic epidermis. To validate our hypothesis, HaCaT cells and primary human keratinocytes were treated with chemerin (5, 10, and 20 ng/mL for 24 hours). Enzyme-linked immunosorbent assay (ELISA) was used to determine the secretion of inflammatory factors. Nuclear factor-κB (NF-κB) activation and p65 acetylation were evaluated by Western blot analysis. The expression and activity of sirtuin 1 (sirt1), a deacetylase act on p65, were also analyzed. The results showed that chemerin prompted inflammatory factors secretion, NF-κB activation and p65 acetylation through chemerin receptor 23 receptor. Chemerin constrained the expression and deacetylase activity of sirt1 through augment of reactive oxygen species (ROS) production. Additionally, chemerin exacerbated psoriasiform dermatitis in imiquimod-treated mice model. In conclusion, chemerin can seduce inflammatory response and promote NF-κB activation through inhibition of sirt1 activity by ROS production.

Background/Aims: Wnt5a is overexpressed in psoriasis lesions, however the mechanism by which Wnt5a is involved in the pathogenesis of psoriasis is not clear. To address this, the expression of Wnt5a in psoriatic lesions and its effect on keratinocyte cell proliferation and apoptosis was examined in vitro. Methods: The expression levels of WNT5A, and genes encoding its receptors frizzled2 (FZD2) and frizzled5 (FZD5) were examined in samples obtained from individuals with psoriasis and healthy controls. Knockdown of Wnt5a with short interfering (si)RNAs was performed in cultured HaCaT keratinocytes and normal human keratinocytes (NHK), and the expression of Wnt5a, protein kinase C (PKC), and β-catenin were determined, and cell cycle activity, proliferation and apoptosis were assessed. Results: The expression of WNT5A, FZD2 and FZD5 mRNA and protein were increased in psoriatic lesions. Wnt5a knockdown suppressed proliferation and induced apoptosis in HaCaT and NHK cells. Additionally, expression of PCNA, MKI67, CCND1, BCL2, CTNNB1, and genes encoding PKC and survivin were downregulated, whereas CASP3 was upregulated. The mRNA levels of the Wnt pathway inhibitors DKK1 and SFRP1 were upregulated, Western blotting analyses demonstrated reduction in β-catenin and PKC protein levels. Conclusion: Knockdown of Wnt5a suppresses the proliferation of keratinocytes and induces apoptosis by inhibiting the Wnt/β-catenin or Wnt5a/Ca2+ pathways.

Benign chronic familial pemphigus or Hailey-Hailey disease (HHD, OMIM 169600) is a rare, autosomal dominant blistering skin disorder characterized by suprabasal cell separation (acantholysis) of the epidermis. To date, the proteomic changes in skin lesions from HHD patients has not been reported yet. In this study, a sample of skin lesions from HHD patients was collected for isobaric tags for relative and absolute quantitation to analyze proteome changes compared with unaffected individuals. The 134 differentially expressed proteins were assigned to at least one Gene Ontology term, and 123 annotated proteins with significant matches were assigned to 187 known metabolic or signaling pathways listed in the Kyoto Encyclopedia of Genes and Genomes. Most of the altered proteins in skin lesions of HHD patients were enriched in pathways involved in the PI3K-Akt signaling, focal adhesion, extracellular matrix (ECM)-receptor interaction, and protein digestion and absorption, such as collagen family members, microfibril-associated glycoprotein 4 and plakophilin. The changes of proteins related to cell adhesion, ECM-receptor interaction, and protein folding and glycosylation suggested that strategy targeted to alter cell junction and extracellular microenvironment might provide a potential treatment for HHD.

Metformin exhibits antiproliferative and proapoptotic effects in a variety of diseases, characterized by malignant and nonmalignant hyperplastic cells; however, the underlying molecular mechanism of metformin in psoriasis has not been elucidated. In the current study, we found that after metformin treatment the proliferation of human immortalized keratinocytes (HaCaT) was significantly inhibited, while cell apoptosis was increased in a dose-dependent manner, accompanied with enhanced protein expression of acyl-coenzyme A dehydrogenase 10 (ACAD10). Furthermore, mechanism analysis revealed that ACAD10 expression is induced by downregulated activities of mechanistic target of rapamycin 1 (mTORC1) signaling rather than AMP-activated protein kinase signaling. The inactivation of mTORC1 by rapamycin pretreatment or rotenone-induced mitochondrial complex inhibition showed a similar effect because of the metformin treatment on the proliferation and apoptosis of HaCaT keratinocytes. Overexpression of mTORC1 almost reversed the antiproliferation and proapoptosis effects induced by metformin. This study showed that the metformin treatment inhibited HaCaT cells proliferation and promoted apoptosis by affecting the mitochondrial-mTORC1 signaling and elevated the ACAD10 expression. Hence, metformin can be used as a potential therapeutic agent for psoriasis.

MicroRNAs (miRNAs) have emerged as critical regulators for malignant melanoma development. miR-485-5p has been suggested as a tumor-suppressive miRNA in many types of human malignancies. However, the role of miR-485-5p in melanoma remains unknown. In this study, we aimed to explore the potential role and underlying mechanism of miR-485-5p in the regulation of melanoma development. Here, we showed that miR-485-5p was significantly decreased in melanoma tissues and cell lines compared with their corresponding controls. Transwell invasion assay showed that miR-485-5p overexpression markedly inhibited melanoma cell invasion. WST-1 and cell cycle assays exhibited that miR-485-5p overexpression significantly suppressed melanoma cell proliferation. By contrast, miR-485-5p suppression promoted the invasion and proliferation of melanoma cells. Using bioinformatics analysis, we observed that miR-485-5p potentially targets the 3'-untranslated region (3'-UTR) of Frizzled7 (FZD7). Dual-luciferase assay confirmed the direct binding between miR-485-5p and FZD7 3'-UTR. Meanwhile, real-time quantitative polymerase chain reaction and Western blot analysis showed that miR-485-5p overexpression suppressed FZD7 expression, whereas miR-485-5p suppression resulted in the opposite effect. Moreover, miR-485-5p expression was observed to be inversely correlated with FZD7 mRNA expression in melanoma tissues. Further experiments showed that miR-485-5p regulated Wnt signaling. The restoration of FZD7 expression markedly reversed the antitumor effects induced by miR-485-5p overexpression in melanoma cells. Taken together, our study suggests that miR-485-5p represses melanoma cell invasion and proliferation by suppressing FZD7, indicating a new tumor-suppressive role for miR-485-5p in melanoma. The miR-485-5p/FZD7 axis may provide novel insights into understanding the molecular pathogenesis of melanoma and may be a promising therapeutic target for melanoma.

Previous research indicates that microRNA-25 (miR-25) regulates carcinogenesis and the progression of various cancers, but the role of miR-25 in melanoma remains unclear. We observed that miR-25 was significantly upregulated in melanoma cell lines and tissue samples. Downregulation of miR-25 markedly suppressed invasion and proliferation of melanoma cells in vitro; however, overexpression of miR-25 markedly increased melanoma cell invasion and proliferation. Moreover, we observed Dickkopf-related protein 3 (DKK3) as a direct target of miR-25 in vitro. Upregulation of DKK3 partially attenuated the oncogenic effect of miR-25 on melanoma cells. Ectopic expression of miR-25 in melanoma cells induced β-catenin accumulation in nuclear and inhibited TCF4 (T cell factor 4) activity, as well as the expression of c-Myc and Cyclin D1. In a nude xenograft model, miR-25 upregulation significantly increased A375 melanoma growth. In summary, miR-25 is upregulated in melanoma and promotes melanoma cell proliferation and invasion, partially by targeting DKK3. These results were indicated that miR-25 may serve as a potential target for the treatment of melanoma in the future.

The gene ATP2C1 is identified as the defective gene in Hailey-Hailey disease (HHD). The nonsense and missense are two common types of mutations and have, respectively, been detected in many HHD patients. The aims of our study were to identify the pathogenic ATP2C1 abnormality in Chinese HHD patients, and to compare nonsense and missense mutations in vivo to provide further understanding of the molecular and the physiological basis of HHD. The nucleotide sequencing of the ATP2C1 gene was performed in HHD patients, unaffected family members and 100 unrelated individuals. Meanwhile, we detected and analyzed the clinical manifestations, the expression of ATP2C1 mRNA and hSPCA1 protein in the two types of mutations. Three heterozygous mutations were identified, including a previously reported nonsense mutation (R799X), two novel missense mutations (D644G) and (R417K). The results of comparisons between two types of mutations showed that the common clinical features, the similarly low-level expressions of ATP2C1 mRNA and hSPCA1 protein, but the ATP2C1 mRNA expression of nonsense mutation was lower than missense mutation and even less than half the level of normal people. Our findings expand the known spectrum of ATP2C1 mutations in HHD. We supported the haploinsufficiency theory as prevalent mechanism in both types of mutations, and believed that the differences of ATP2C1 mRNA expressions in peripheral blood may relate with the type of mutation and reflect the state of illness of patients.

In current study, a water-soluble polysaccharide (GP-I), with a molecular mass of 33 kDa, was purified from Gynostemma pentaphyllum. Gas chromatography (GC) analysis suggested that it was composed of Glc, Gal, Man, Rha and Ara with a ratio of 5.3: 4.2: 3.0: 0.7: 0.8. The GP-I (25, 50, 100, 200 and 400 μg/ml) was found to have significant anti-proliferative effects on HaCat cells in a dose-dependent manner, as measured by MTT assay. On the contrary, Trypan blue exclusion experiment indicated that GP-I had no cytotoxicity to HaCat cells. Moreover, the decrease of mitochondrial membrane potential (MMP) in GP-I treated cells was also observed, indicating apoptosis in HaCat cells. Besides, tumor necrosis factor-α (TNF-α), a vital pro-inflammatory cytokine in psoriasis, in the supernatant of HaCat cells was dramatically reduced by GP-I. Collectively, these findings suggested that GP-I was a promising agent to be developed for psoriasis treatment in clinical therapy.