ABSTRACT
Keratin 6A (KRT6A) is involved in the pathogenesis of various skin diseases. However, the reports on the roles of KRT6A in atopic dermatitis (AD) are limited. This study aimed to investigate the potentials of KRT6A in AD. mRNA levels were detected by RT-PCR. Cytokine release was determined by ELISA. Protein expression was determined using Western blot. Cell viability was determined by CCK-8. Cytotoxicity was detected by LDH assay. Cell death was determined by TUNEL. The pyroptosis of keratinocytes was detected using flow cytometry. We found that KRT6A was overexpressed in AD patients. Moreover, KRT6A was stimulated after exposed to proinflammatory cytokines. Overexpressed KRT6A suppressed inflammatory response, while KRT6A knockdown exerted the opposite effects. Overexpressed KRT6A suppressed inflammation-induced pyroptosis of keratinocytes. Additionally, KRT6A negatively regulated interleukin-17a (IL-17a) expression, blocking IL-17 signaling. IL-17a overexpression antagonized the effects of KRT6A and promoted pyroptosis of keratinocytes. In conclusion, KRT6A exerted protective functions in AD via regulating IL-17 signaling. This KRT6A/IL-17 may be a novel target for AD.
Subject(s)
Dermatitis, Atopic , Interleukin-17 , Humans , Interleukin-17/genetics , Interleukin-17/metabolism , Interleukin-17/pharmacology , Pyroptosis , Keratin-6/metabolism , Keratin-6/pharmacology , Keratinocytes/metabolism , Signal Transduction , Cytokines/metabolism , Dermatitis, Atopic/genetics , Dermatitis, Atopic/metabolismABSTRACT
BACKGROUND: To examine the effects of Keratin 6A (KRT6A) protein on the proliferation, migration and invasion abilities of lung adenocarcinoma cells, and to analyse the relationship between the expression level of KRT6A protein and the survival prognosis of lung adenocarcinoma patients. METHODS: Western Blot was used to detect the expression of KRT6A protein in lung adenocarcinoma cell lines. CCK-8 experiment and colony formation assays were performed to detect the proliferation ability. Wound healing assay and transwell migration assay were conducted to detect the migration ability. Transwell invasion assay was conducted to detect the invasion ability. Immunohistochemistry was used to detect the expression of KRT6A protein in lung adenocarcinoma tissues. RESULTS: We first found that the expression of KRT6A protein in lung adenocarcinoma cell lines was low. After overexpressed KRT6A protein in lung adenocarcinoma cells, we then found that KRT6A protein could not only inhibit the proliferation ability of lung adenocarcinoma cells but also inhibit them migration and invasion abilities. In addition, we also found that there had obvious difference in the expression of KRT6A protein in between patients. And through further analysis, we finally discovered that high expression of KRT6A protein was related to favourable prognosis in lung adenocarcinoma patients. CONCLUSIONS: KRT6A protein inhibits the proliferation, migration and invasion abilities of lung adenocarcinoma cells, and high expression of KRT6A protein is a predictor of good prognosis in patients with lung adenocarcinoma.
Subject(s)
Adenocarcinoma of Lung/genetics , Keratin-6/genetics , Keratin-6/pharmacology , Lung Neoplasms/pathology , Adenocarcinoma of Lung/metabolism , Adenocarcinoma of Lung/mortality , Adenocarcinoma of Lung/pathology , Cell Movement/drug effects , Cell Movement/genetics , Cell Proliferation/drug effects , Cell Proliferation/genetics , Female , Gene Expression Regulation, Neoplastic/genetics , Humans , Immunohistochemistry/methods , Keratin-6/metabolism , Male , Neoplasm Invasiveness/genetics , Neoplasm Invasiveness/pathology , Prognosis , Sincalide/metabolismABSTRACT
Over-expression of ornithine decarboxylase (ODC) is known to be involved in the epidermal carcinogenesis. However, the mechanism by which it enhances skin carcinogenesis remains undefined. Recently, role of stem cells localized in various epidermal compartments has been shown in the pathogenesis of skin cancer. To direct ODC expression in distinct epidermal compartments, we have developed keratin 6 (K6)-ODC/SKH-1 and keratin 14 (K14)-ODC/SKH-1 mice and employed them to investigate the role of ODC directed to these epidermal compartments on UVB-induced carcinogenesis. K6-driven ODC over-expression directed to outer root sheath (ORS) of hair follicle was more effective in augmenting tumorigenesis as compared to mice where K14-driven ODC expression was directed to inter-follicular epidermal keratinocytes. Chronically UVB-irradiated K6-ODC/SKH-1 developed 15±2.5 tumors/mouse whereas K14-ODC/SKH-1 developed only 6.8±1.5 tumors/mouse. K6-ODC/SKH-1 showed augmented UVB-induced proliferation and much higher pro-inflammatory responses than K14-ODC/SKH-1 mice. Tumors induced in K6-ODC/SKH-1 were rapidly growing, invasive and ulcerative squamous cell carcinoma (SCC) showing decreased expression of epidermal polarity marker E-cadherin and enhanced mesenchymal marker, fibronectin. Interestingly, the number of CD34/CK15/p63 positive stem-like cells was significantly higher in chronically UVB-irradiated K6-ODC/SKH-1 as compared to K14-ODC/SKH-1 mice. Reduced Notch1 expression was correlated with the expansion of stem cell compartment in these animals. However, other signaling pathways such as DNA damage response or mTOR signaling pathways were not significantly different in tumors induced in these two murine models suggesting the specificity of Notch pathway in this regard. These data provide a novel role of ODC in augmenting tumorigenesis via negatively regulated Notch-mediated expansion of stem cell compartment.
