Project description:A nonsense mutation in ARID1A was identified by next generation sequencing in non-dysplastic Barrett's esophagus [BE] tissue and esophageal adenocarcinoma [EAC] tissue of a patient diagnosed with EAC. Immunohistochemistry performed on an independent archival cohort demonstrated ARID1A protein loss in 0% (0/76), 4.9% (2/40), 14.3% (4/28), 16.0% (8/50), and 12.2% (12/98) of normal squamous epithelium, BE, low-, high-grade dysplasia, and EAC tissues, respectively. Enhanced cell growth, proliferation and invasion were observed upon ARID1A knockdown in EAC cells. ARID1A was knocked down in OE33 cells (Sample MS_1 and MS_3) using on-TARGET smartpool ARID1A siRNA. At the same time, OE33 cells were transfected with a non-targeting siRNA, and these experiments (Samples MS_2 and MS_4) functioned as mock controls. Cells were harvested after 48 hours and total RNA was extracted using the Rneasy kit (Qiagen) Aim Affymetrix Human PrimeView Gene Expression Array : to determine the downstream effectors of ARID1A that are likely to contribute to the oncogenic phenotype caused by ARID1A down-regulation. Two biological replicates of each condition (2x ARID1A knockdown, and 2x Mock) were used for the microarray experiment.
Project description:A nonsense mutation in ARID1A was identified by next generation sequencing in non-dysplastic Barrett's esophagus [BE] tissue and esophageal adenocarcinoma [EAC] tissue of a patient diagnosed with EAC. Immunohistochemistry performed on an independent archival cohort demonstrated ARID1A protein loss in 0% (0/76), 4.9% (2/40), 14.3% (4/28), 16.0% (8/50), and 12.2% (12/98) of normal squamous epithelium, BE, low-, high-grade dysplasia, and EAC tissues, respectively. Enhanced cell growth, proliferation and invasion were observed upon ARID1A knockdown in EAC cells. ARID1A was knocked down in OE33 cells (Sample MS_1 and MS_3) using on-TARGET smartpool ARID1A siRNA. At the same time, OE33 cells were transfected with a non-targeting siRNA, and these experiments (Samples MS_2 and MS_4) functioned as mock controls. Cells were harvested after 48 hours and total RNA was extracted using the Rneasy kit (Qiagen)
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:Transcriptional profiling of human mesenchymal stem cells comparing normoxic MSCs cells with hypoxic MSCs cells. Hypoxia may inhibit senescence of MSCs during expansion. Goal was to determine the effects of hypoxia on global MSCs gene expression.
Project description:Gene methylation profiling of immortalized human mesenchymal stem cells comparing HPV E6/E7-transfected MSCs cells with human telomerase reverse transcriptase (hTERT)- and HPV E6/E7-transfected MSCs. hTERT may increase gene methylation in MSCs. Goal was to determine the effects of different transfected genes on global gene methylation in 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.
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. One-condition experment, gene expression of 3A6