Project description:Kallikrein-related peptidase 3 (KLK3, also known as prostate-specific antigen, PSA) is a chymotrypsin-like kallikrein that has been shown to have anti-angiogenic properties. KLK3 expression in prostate cancer is associated with low microvessel density. We have previously shown in a human umbilical vein endothelial cell (HUVEC) model that the anti-angiogenic effect of KLK3 is related to its enzymatic activity. However, the mechanism of this effect remains to be clarified. To this end we have used a DNA microarray to study the KLK3-induced changes in gene expression associated with reduction of HUVEC tube formation. Among the 41000 genes studied, 311 were differentially expressed in control and KLK3-treated cells. These changes were enriched in several pathways, including the pathways associated with proteasome, ubiquitin-mediated proteolysis, focal adhesion and regulation of actin cytoskeleton. Furthermore, the changes were opposite to those described previously to occur during tubulogenesis. In conclusion, our results show that KLK3 induces gene expression changes in HUVECs. While these changes might be relevant for the mechanism by which KLK3 exerts its anti-angiogenic activity, it cannot be judged by the present results whether the changes are secondary to morphogenic differentiation of the cells or the primary mechanism mediating the effect of KLK3. Keywords: KLK3 treatment, tube formation Human umbilical vein endothelial cells (HUVECs) were isolated from umbilical cord veins and grown in Endothelial Cell Basal Medium supplemented with an Endothelial Cell Growth Medium Supplement Pack (PromoCell). The cells were cultured on Matrigel basement membrane prepara-tion together with 500 nM enzymatically active KLK3 (PSA). Phosphate buffered saline (PBS) was used for control. HUVECs were grown on Matrigel for 18 h. RNA was isolated from KLK3-treated and control HUVECs from three different individuals. Cell Recovery Solution (BD Biosciences) was used to detach cells from the Matrigel. Total RNA was isolated with the RNeasy Mini Kit (Qiagen) according to manufacturerâ??s instructions. RNA con-centration and quality of the samples was determined with an Agilent 2100 bioanalyser (Agilent Technologies) by measuring the RNA integrity number (RIN). All samples contained high quality RNA (RIN 9.5-10). DNA microarray analysis was performed with the Agilent Whole Human Genome Oligo Microar-ray 4x44K (G4112F) (Agilent Technologies Inc.) following the manufacturerâ??s protocol. Total RNA (1 ï?g) was labeled using the RNA input fluorescent linear amplification kit according to the manufacturer's recommendations (Agilent Technologies Inc.). RNA was hybridized on Agilent's Human 4x44K Oligo Microarrays containing 44000 features (41000 unique genes and transcripts). Pre-processing of the data was performed by Feature Extraction software (v 7.5.1).
Project description:Kallikrein-related peptidase 3 (KLK3, also known as prostate-specific antigen, PSA) is a chymotrypsin-like kallikrein that has been shown to have anti-angiogenic properties. KLK3 expression in prostate cancer is associated with low microvessel density. We have previously shown in a human umbilical vein endothelial cell (HUVEC) model that the anti-angiogenic effect of KLK3 is related to its enzymatic activity. However, the mechanism of this effect remains to be clarified. To this end we have used a DNA microarray to study the KLK3-induced changes in gene expression associated with reduction of HUVEC tube formation. Among the 41000 genes studied, 311 were differentially expressed in control and KLK3-treated cells. These changes were enriched in several pathways, including the pathways associated with proteasome, ubiquitin-mediated proteolysis, focal adhesion and regulation of actin cytoskeleton. Furthermore, the changes were opposite to those described previously to occur during tubulogenesis. In conclusion, our results show that KLK3 induces gene expression changes in HUVECs. While these changes might be relevant for the mechanism by which KLK3 exerts its anti-angiogenic activity, it cannot be judged by the present results whether the changes are secondary to morphogenic differentiation of the cells or the primary mechanism mediating the effect of KLK3. Keywords: KLK3 treatment, tube formation
Project description:Transcriptional profiling of Homo sapiens inflammatory skin diseases (whole skin biospies): Psoriasis (Pso), vs Atopic Dermatitis (AD) vs Lichen planus (Li), vs Contact Eczema (KE), vs Healthy control (KO) In recent years, different genes and proteins have been highlighted as potential biomarkers for psoriasis, one of the most common inflammatory skin diseases worldwide. However, most of these markers are not psoriasis-specific but also found in other inflammatory disorders. We performed an unsupervised cluster analysis of gene expression profiles in 150 psoriasis patients and other inflammatory skin diseases (atopic dermatitis, lichen planus, contact eczema, and healthy controls). We identified a cluster of IL-17/TNFα-associated genes specifically expressed in psoriasis, among which IL-36γ was the most outstanding marker. In subsequent immunohistological analyses IL-36γ was confirmed to be expressed in psoriasis lesions only. IL-36γ peripheral blood serum levels were found to be closely associated with disease activity, and they decreased after anti-TNFα-treatment. Furthermore, IL-36γ immunohistochemistry was found to be a helpful marker in the histological differential diagnosis between psoriasis and eczema in diagnostically challenging cases. These features highlight IL-36γ as a valuable biomarker in psoriasis patients, both for diagnostic purposes and measurement of disease activity during the clinical course. Furthermore, IL-36γ might also provide a future drug target, due to its potential amplifier role in TNFα- and IL-17 pathways in psoriatic skin inflammation. In recent years, different genes and proteins have been highlighted as potential biomarkers for psoriasis, one of the most common inflammatory skin diseases worldwide. However, most of these markers are not psoriasis-specific but also found in other inflammatory disorders. We performed an unsupervised cluster analysis of gene expression profiles in 150 psoriasis patients and other inflammatory skin diseases (atopic dermatitis, lichen planus, contact eczema, and healthy controls). We identified a cluster of IL-17/TNFα-associated genes specifically expressed in psoriasis, among which IL-36γ was the most outstanding marker. In subsequent immunohistological analyses IL-36γ was confirmed to be expressed in psoriasis lesions only. IL-36γ peripheral blood serum levels were found to be closely associated with disease activity, and they decreased after anti-TNFα-treatment. Furthermore, IL-36γ immunohistochemistry was found to be a helpful marker in the histological differential diagnosis between psoriasis and eczema in diagnostically challenging cases. These features highlight IL-36γ as a valuable biomarker in psoriasis patients, both for diagnostic purposes and measurement of disease activity during the clinical course. Furthermore, IL-36γ might also provide a future drug target, due to its potential amplifier role in TNFα- and IL-17 pathways in psoriatic skin inflammation.
Project description:Endothelial cells are critical for angiogenesis, and microRNAs plays important roles in this process. We investigated the regulatory role of microRNAs in endothelial cells of hepatocellular carcinoma (HCC) by examining the microRNA expression profile of human umbilical vein endothelial cells (HUVECs) in the absence or presence of human HCC cells, and identified miR-146a as the most highly up-regulated microRNA. Furthermore, we revealed that miR-146a promoted the expression of platelet-derived growth factor receptor (PDGFRA) in HUVECs, and this process was mediated by BRCA1. Overexpression of PDGFRA in the ECs of HCC tissues was associated with microvascular invasion, and predicted a poorer prognosis. These results suggest that MiR-146a plays a key role in regulating the angiogenic activity of ECs in HCC through miR-146a-BRCA1-PDGFRA pathway. MiR-146a may emerge as a potential anti-angiogenic target on ECs for HCC therapy. We have employed whole genome OneArray to examine the genome expression changes of HUVECs overexpressing miR-146a.
Project description:Effect of TNF-alpha on microRNAs levels in Human Umbilical Endothelial Cells (HUVECs). HUVEC that were treated or not for 2 or 24 hours with TNF (10 ng/ml). Duplicate samples (1 or 2) of two different isolations of HUVEC (A or B)
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
Project description:Kynureninase is a member of a large family of catalytically diverse but structurally homologous pyridoxal 5'-phosphate (PLP) dependent enzymes known as the aspartate aminotransferase superfamily or alpha-family. The Homo sapiens and other eukaryotic constitutive kynureninases preferentially catalyze the hydrolytic cleavage of 3-hydroxy-l-kynurenine to produce 3-hydroxyanthranilate and l-alanine, while l-kynurenine is the substrate of many prokaryotic inducible kynureninases. The human enzyme was cloned with an N-terminal hexahistidine tag, expressed, and purified from a bacterial expression system using Ni metal ion affinity chromatography. Kinetic characterization of the recombinant enzyme reveals classic Michaelis-Menten behavior, with a Km of 28.3 +/- 1.9 microM and a specific activity of 1.75 micromol min-1 mg-1 for 3-hydroxy-dl-kynurenine. Crystals of recombinant kynureninase that diffracted to 2.0 A were obtained, and the atomic structure of the PLP-bound holoenzyme was determined by molecular replacement using the Pseudomonas fluorescens kynureninase structure (PDB entry 1qz9) as the phasing model. A structural superposition with the P. fluorescens kynureninase revealed that these two structures resemble the "open" and "closed" conformations of aspartate aminotransferase. The comparison illustrates the dynamic nature of these proteins' small domains and reveals a role for Arg-434 similar to its role in other AAT alpha-family members. Docking of 3-hydroxy-l-kynurenine into the human kynureninase active site suggests that Asn-333 and His-102 are involved in substrate binding and molecular discrimination between inducible and constitutive kynureninase substrates.