Project description:Purpose: Even in last stage of metastatic castration-resistant prostate cancer, androgen receptor (AR) signaling remains active.To derive high metastatic prostate cancer (PCa), we labeled AR-positive but castration-resistant 22Rv1 PCa cells with luciferase gene (22Rv1-Luc2) and these cells were orthotopically implanted in mouse prostate for spontaneous progression. Methods: 2 × 10^5 of luciferase-expressing 22Rv1 cells (22Rv1-Luc2) cells were implanted in the anterior prostate of nude mice. After 12-14 weeks, the host mice were necropsied and the metastases from lumbar lymph nodes and primary tumors were dissected under laminar flow. Tumor tissues were minced using sterile scalpels and further digested with Collagenase D for 1 h. The lymph node metastatic cancer cells, named 22Rv1-M1, were orthotopically reimplanted in nude mice. At 12 weeks, the secondary metastases were isolated in the lumbar lymph nodes and designated as 22Rv1-M2 cells. Suspension of 1 × 10^6 22Rv1-M2 cells in DPBS was injected into nude mice through the tail vein, and mice developed metastases (22Rv1-M3) after 6 week. This procedure was repeated once to attain the 22Rv1-M4. Results: 22Rv1-derived metastatic cell lines exhibit increased in vitro and in vivo invasion activity as the progression from 22Rv1 to M4. Transcriptomic analysis of genome-wide gene expression in the M4 tumors reveal the unique gene expression profile compared to 22Rv1 tumors. Conclusions: Transcriptomic data provide the gene network for decoding the mechanism of PCa metastasis.
Project description:Activation of the inflammatory circuits occurs frequently in cancer cells. However the molecular details linking inflammation to transformation and progression are still unknown. In this study we report for the first time, that activation of the ETS factor ESE1 is a key event connecting inflammatory signaling with prostate cancer progression. We report that ESE1 is induced upon IL-1 beta stimulation by NFKB and mediates key transcriptional changes involving cell adhesion, migration and invasion. ESE1 activation in turn induces NFKB transcriptional activation and intranuclear translocation and mediates the transforming phenotypes linked to the activation of IL-1B. Transcriptional signatures and immunohistochemistry revealed that this ESE1-NFKB regulatory circuit also operates in prostate tumors, particularly in those with significant elevation of ESE1. Thus, ESE1 promotes an inflammatory feed forward loop positively leading to prostate cancer progression. Pharmacological NFKB inhibition reverted the transformed status of ESE1 cell lines providing a rationale for context-dependent therapeutic strategies in ESE1 activated tumors. These studies find a previously unrecognized link between ETS and activation of the NFKB pathway and open new avenues for prostate cancer treatment. Gene expression analysis of a control cell line (22Rv1-pcDNA3.1) and a testing cell lines (22Rv1-ESE1), with two replicates, with dye swap, performed for each sample.
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: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.