Project description:The protein tyrosine phosphatase PRL-1 (Gene Symbol: PTP4A1) has been identified as an important oncogene with roles in promoting cell proliferation, survival, migration, invasion, and metastasis. However, little is currently known about the signaling pathways through which it mediates its effects. Studies have shown a relationship between PRL-1 and the expression or activity levels of various molecules involved in integrin-mediated cell signaling. These integrin-responsive players can promote re-arrangements in the actin cytoskeleton that are central to cell motility, invasion, and metastasis. Therefore, to investigate the effects of PRL-1 overexpression in human embryonic kidney 293 (HEK293) cells, we used qRT-PCR to examine the expression levels of 184 genes which either were identified by microarray and proteomic analysis to be differentially expressed in response to PRL-1 or have known associations to integrin-mediated signaling, cytoskeletal remodeling, and/or cell motility. Total RNA was extracted from duplicate cultures of HEK293 cells stably overexpressing PRL-1 (HEK293-PRL-1) and HEK293 cells stably transfected with empty pcDNA4 vector (HEK293-Vector). Samples were analyzed using custom TaqMan Array 96-well Plates to examine the expression of 184 genes with known involvement in or association with signaling pathways related to integrin-mediated cell adhesion, cytoskeletal remodeling, and/or cell motility.
Project description:The protein tyrosine phosphatase PRL-1 (Gene Symbol: PTP4A1) has been identified as an important oncogene with roles in promoting cell proliferation, survival, migration, invasion, and metastasis. However, little is currently known about the signaling pathways through which it mediates its effects. Studies have shown a relationship between PRL-1 and the expression or activity levels of various molecules involved in integrin-mediated cell signaling. These integrin-responsive players can promote re-arrangements in the actin cytoskeleton that are central to cell motility, invasion, and metastasis. Therefore, to investigate the effects of PRL-1 overexpression in human embryonic kidney 293 (HEK293) cells, we used qRT-PCR to examine the expression levels of 184 genes which either were identified by microarray and proteomic analysis to be differentially expressed in response to PRL-1 or have known associations to integrin-mediated signaling, cytoskeletal remodeling, and/or cell motility.
Project description:Purpose: Esophageal squamous cell carcinoma (ESCC) is a serious malignant tumor, it affects human health. We analyzed the correlation between serum Stathmin levels and ESCC, further elucidated the molecular mechanisms how Stathmin promotes ESCC cell invasion and metastasis. Methods: Stathmin levels in ESCC and healthy control serum was detected by enzyme-linked immunosorbent assay (ELISA), and analyzed the clinical parameters. We established ESCC cells with Stathmin overexpression or knockdown, next evaluated the effects of Stathmin on invasion, metastasis and proliferation in ESCC. The expression levels of the integrin family, focal adhesion kinase (FAK) protein and extracellular signal-regulated kinase (ERK) were detected by immunoblotting. Results: Serum levels of Stathmin were significantly higher in ESCC and associated with lymph node metastasis, tumor stage and size. Furthermore, we found Stathmin promotes migration, invasion and proliferation of ESCC cells in vitro and in vivo. Further study confirmed that the activation of integrinα5β1/FAK/ERK pathway is increased in Stathmin overexpression cells, this pathway contribute to strengthen cell adhesion. Stathmin accelerates the cell motility by enhancing cell adhesion ability. Conclusion: Stathmin may be a potential biomarker for ESCC clinical detection, and it can promotes ESCC cell invasion and metastasis through the integrinα5β1/FAK/ERK pathway. The differentially expressed genes were analyzed by Human Transcriptome Array, and confirmed by RT-PCR.
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: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.