Rabbit Anti-Human KLK5 Polyclonal Antibody

Background: Topical retinoids induce skin fragility. As corneodesmosomes are important adhesion structures in the epidermal cohesion, an effect of retinoids on corneodesmosomes has been suspected. Objective: The aim of this study was to investigate the effect of retinoid on the expression of corneodesmosomal components including desmoglein (DSG) 1, desmocollin (DSC) 1, corneodesmosin (CDSN) and kallikrein (KLK)s. Methods: 2% all-trans-retinol or ethanol was applied to the back of hairless mice for five days, and the structure of the stratum corneum was examined by transmission electron microscopy. The cultured human keratinocytes were treated with all-trans-retinoic acid (RA) in low or high calcium media for 24 hours. Results: Topical retinol increased corneocyte detachment and degradation of corneodesmosomes. RA significantly decreased DSG1 and DSC1 expression at the mRNA and protein levels in keratinocytes that were cultured in both low- and high-calcium media. On the other hand, CDSN mRNA levels did not decrease in low-calcium media or increase in high-calcium media after RA treatment. KLK5 and KLK7 expression did not increase after RA treatment. Conclusion: Our results indicate that DSG1 and DSC1 downregulation by RA could be related to the increased degradation of corneodesmosomes and consequent desquamation induced by retinoids. (Ann Dermatol 23(4) 439 similar to 447, 2011)

BACKGROUND: Kallikrein-related peptidases (KLKs) are a family of serine proteases that have been shown to be dysregulated in several malignancies including ovarian cancer. The control of kallikrein genes and their physiological function in cancer is not well understood. We hypothesized that microRNAs (miRNAs) represent a novel mechanism for post-transcriptional control of KLK expression in cancer. METHODS: We first analysed miRNA expression in ovarian cancer in silico. A total of 98 miRNAs were reported to have altered expression in ovarian cancer. Three of these miRNAs were predicted to target KLK10. We experimentally verified the predicted miR-KLK10 interaction using two independent techniques, a luciferase assay with a construct containing the KLK10 3' untranslated region (UTR), pMIR-KLK10, and measuring KLK10 protein levels after transfection with miRNA. RESULTS: When we co-transfected cells with pMIR-KLK10 and either let-7f, miR-224, or mR-516a, we saw decreased luciferase signal, suggesting that these miRNAs can target KLK10. We then examined the effect of these three miRNAs on KLK10 protein expression and cell growth. Transfection of all miRNAs, let-7f, miR-224, and miR-516a led to a decrease in protein expression and cellular growth. This effect was shown to be dose dependent. The KLK10 protein levels were partially restored by co-transfecting let-7f and its inhibitor. In addition, there was a slight decrease in KLK10 mRNA expression after transfection with let-7f. CONCLUSIONS: Our results confirm that KLKs can be targeted by more than one miRNA. Increased expression of certain miRNAs in ovarian cancer can lead to decreased KLK protein expression and subsequently have a negative effect on cell proliferation. This dose-dependent effect suggests that a 'tweaking' or 'fine-tuning' mechanism exists in which the expression of one KLK can be controlled by multiple miRNAs. These data together suggest that miRNA may be used as potential therapeutic options and further studies are required. British Journal of Cancer (2010) 102, 1244-1253. doi: 10.1038/sj.bjc.6605634 www.bjcancer.com Published online 30 March 2010 (C) 2010 Cancer Research UK