Project description:Comparing the gene expression profiling of HDGF-silenced RD-ES cells and control RD-ES cells to identify genes regulated by HDGF in RD-ES cells. Keywords: expression analysis
Project description:Phase I Safety, Pharmacokinetic and Pharmacogenomic Trial of ES-285, a Novel Marine Cytotoxic Agent Administered as an Infusion over 24 h Every 21 Days in Patients with Solid Tumors Purpose: A dose-escalation, phase I study evaluated the safety, pharmacokinetics, pharmacogenomics and efficacy of ES-285, a novel agent isolated from a marine mollusc, in adult cancer patients. Experimental design: Patients received a 24-hour i.v. infusion of ES-285 once every 3 weeks until disease progression or unacceptable toxicity. The starting dose was 4mg/m2. Dose escalation proceeded according to the worst toxicity observed in the previous cohort. Results: 28 patients were treated with 72 courses of ES-285 across 8 dose levels. No doselimiting toxicities (DLTs) were seen between 4mg/m2 and 128mg/m2. Two out of 4 patients treated at 256mg/m2 had dose-limiting reversible grade 3 transaminitis; one patient at 256mg/m2 also had transient grade 3 central neurotoxicity. One of 3 patients subsequently treated at 200mg/m2 died following drug-related central neurotoxicity. Pharmacokinetic studies indicated dose-proportionality with high volume of distribution (median Vss at 256mg/m2 was 2389L, range 1615-4051L) and long elimination half life (median t1/2 at 256mg/m2 was 29h, range 21-32h). The 3 patients with DLT had the highest drug exposure. Pharmacogenomic studies of paired surrogate tissue samples identified changes in gene expression following treatment that correlated with increasing dose. Pre-treatment 59- and 49-gene sets were identified in blood and skin respectively, that may predict DLT. Disease stabilisation for 6 to 18 weeks was recorded in 9 patients. Conclusion: Using this schedule, 128 mg/m2 was considered safe and feasible. At this dose, pharmacologically relevant concentrations of drug were safely achieved with pharmacogenomic studies indicating changes in the expression of genes of potential biological relevance. Keywords: dose response
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:Comparing the gene expression profiling of HDGF-silenced RD-ES cells and control RD-ES cells to identify genes regulated by HDGF in RD-ES cells. Keywords: expression analysis Control RD-ES cells and HDGF-silenced RD-ES cells were profiled on 22K Human Genome Array
Project description:As the evolution of miRNA genes has been found to be one of the important factors in formation of the modern type of man, we performed a comparative analysis of the evolution of miRNA genes in two archaic hominines, Homo sapiens neanderthalensis and Homo sapiens denisova, and elucidated the expression of their target mRNAs in bain.A comparative analysis of the genomes of primates, including species in the genus Homo, identified a group of miRNA genes having fixed substitutions with important implications for the evolution of Homo sapiens neanderthalensis and Homo sapiens denisova. The mRNAs targeted by miRNAs with mutations specific for Homo sapiens denisova exhibited enhanced expression during postnatal brain development in modern humans. By contrast, the expression of mRNAs targeted by miRNAs bearing variations specific for Homo sapiens neanderthalensis was shown to be enhanced in prenatal brain development.Our results highlight the importance of changes in miRNA gene sequences in the course of Homo sapiens denisova and Homo sapiens neanderthalensis evolution. The genetic alterations of miRNAs regulating the spatiotemporal expression of multiple genes in the prenatal and postnatal brain may contribute to the progressive evolution of brain function, which is consistent with the observations of fine technical and typological properties of tools and decorative items reported from archaeological Denisovan sites. The data also suggest that differential spatial-temporal regulation of gene products promoted by the subspecies-specific mutations in the miRNA genes might have occurred in the brains of Homo sapiens denisova and Homo sapiens neanderthalensis, potentially contributing to the cultural differences between these two archaic hominines.
Project description:PurposeWe investigated the evidence of recent positive selection in the human phototransduction system at single nucleotide polymorphism (SNP) and gene level.MethodsSNP genotyping data from the International HapMap Project for European, Eastern Asian, and African populations was used to discover differences in haplotype length and allele frequency between these populations. Numeric selection metrics were computed for each SNP and aggregated into gene-level metrics to measure evidence of recent positive selection. The level of recent positive selection in phototransduction genes was evaluated and compared to a set of genes shown previously to be under recent selection, and a set of highly conserved genes as positive and negative controls, respectively.ResultsSix of 20 phototransduction genes evaluated had gene-level selection metrics above the 90th percentile: RGS9, GNB1, RHO, PDE6G, GNAT1, and SLC24A1. The selection signal across these genes was found to be of similar magnitude to the positive control genes and much greater than the negative control genes.ConclusionsThere is evidence for selective pressure in the genes involved in retinal phototransduction, and traces of this selective pressure can be demonstrated using SNP-level and gene-level metrics of allelic variation. We hypothesize that the selective pressure on these genes was related to their role in low light vision and retinal adaptation to ambient light changes. Uncovering the underlying genetics of evolutionary adaptations in phototransduction not only allows greater understanding of vision and visual diseases, but also the development of patient-specific diagnostic and intervention strategies.