Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “GENES”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 523 records · Page 29Linked to original sources

Combined gene therapy with suicide gene and interleukin-12 is more efficient than therapy with one gene alone in a murine model of hepatocellular carcinoma.

BACKGROUND/AIMS: Gene therapy has emerged as a new form of treatment for unresectable hepatocellular carcinoma (HCC). We evaluate here the effect of IL-12 and the suicide gene thymidine kinase as single agents and in combination to treat experimental liver cancer. METHODS: Recombinant adenoviruses expressing mouse interleukin-12 (AdCMVIL-12) or thymidine kinase of herpes simplex virus (AdCMVtk) or lacZ reporter gene (AdCMVlacZ) were constructed. The efficacy of the treatment was evaluated in a murine HCC model based on subcutaneous implantation of liver tumor cells (BNL). RESULTS: Transduction of BNL cells after in vitro infection with AdCMVlacZ was very low at multiplicity of infection (moi) of 100, whereas 10-15% of cells were transduced when using moi 1,000. Similarly, production of IL-12 was detectable only in BNL cells infected with AdCMVIL-12 at moi 1,000. In vitro infection of BNL cells with AdCMVIL-12 at moi 100 did not abrogate tumorigenicity, whereas moi 1,000 resulted in inhibition of tumor growth in all mice as well as in abrogation of tumor formation in 3 out of 8 animals. In vivo studies showed that intratumor injection of AdCMVIL-12 induced a dose-dependent effect on tumor regression. However, none of the animals exhibited complete tumor elimination with this treatment. We observed that suppression of tumor growth was more intense in animals treated with the combination of AdCMVIL-12 plus AdCMVtk than in animals which received AdCMVtk or AdCMVIL-12 alone. The combined treatment resulted in a significant increase in animal survival, and 25% of treated animals were free of tumor for over 100 days without recurrence of the disease. CONCLUSIONS: Combination of AdCMVIL-12 and AdCMVtk is more efficient than either of the two vectors alone for the treatment of the murine model of HCC used in this study.

Adenoviridae↗

Real-time PCR based on SYBR-Green I fluorescence: an alternative to the TaqMan assay for a relative quantification of gene rearrangements, gene amplifications and micro gene deletions.

BACKGROUND: Real-time PCR is increasingly being adopted for RNA quantification and genetic analysis. At present the most popular real-time PCR assay is based on the hybridisation of a dual-labelled probe to the PCR product, and the development of a signal by loss of fluorescence quenching as PCR degrades the probe. Though this so-called 'TaqMan' approach has proved easy to optimise in practice, the dual-labelled probes are relatively expensive. RESULTS: We have designed a new assay based on SYBR-Green I binding that is quick, reliable, easily optimised and compares well with the published assay. Here we demonstrate its general applicability by measuring copy number in three different genetic contexts; the quantification of a gene rearrangement (T-cell receptor excision circles (TREC) in peripheral blood mononuclear cells); the detection and quantification of GLI, MYC-C and MYC-N gene amplification in cell lines and cancer biopsies; and detection of deletions in the OPA1 gene in dominant optic atrophy. CONCLUSION: Our assay has important clinical applications, providing accurate diagnostic results in less time, from less biopsy material and at less cost than assays currently employed such as FISH or Southern blotting.

Benzothiazoles↗

Pim-1 kinase inhibits the activation of reporter gene expression in Elk-1 and c-Fos reporting systems but not the endogenous gene expression: an artifact of the reporter gene assay by transient co-transfection.

We have studied the molecular mechanism and signal transduction of pim-1, an oncogene encoding a serine-threonine kinase. This is a true oncogene which prolongs survival and inhibits apoptosis of hematopoietic cells. In order to determine whether the effects of Pim-1 occur by regulation of the mitogen-activated protein kinase pathway, we used a transcriptional reporter assay by transient co-transfection as a screening method. In this study, we found that Pim-1 inhibited the Elk-1 and NFkappaB transcriptional activities induced by activation of the mitogen-activated protein kinase cascade in reporter gene assays. However, Western blots showed that the induction of Elk-1-regulated expression of endogenous c-Fos was not affected by Pim-1. The phosphorylation and activation of neither Erk1/2 nor Elk-1 was influenced by Pim-1. Also, in the gel shift assay, the pattern of endogenous NFkappaB binding to its probe was not changed in any manner by Pim-1. These data indicate that Pim-1 does not regulate the activation of Erk1/2, Elk-1 or NFkappaB. These contrasting results suggest a pitfall of the transient co-transfection reporter assay in analyzing the regulation of transcription factors outside of the chromosome context. It ensures that results from reporter gene expression assay should be verified by study of endogenous gene expression.

Animals↗

Localization of two X-linked mental retardation (XLMR) genes to Xp: MRX37 gene at Xp22.31-p22.32 and a putative MRX gene on Xp22.11-p22.2.

MRX genes of 2 families with X-linked mental retardation (XLMR) were localized by linkage analysis. In family A, the gene was mapped to Xp22.31-p22.32, with significant LOD scores to various Xp22 markers within a distance of 6 Mb between DXS1223 and DXS1224. The MRX gene of this family was designated MRX37. In a mentally retarded female who is a carrier of the MRX37 gene, a random pattern of X inactivation was demonstrated. In family B, a positive LOD score, although not significant (< + 2), was found with the marker DXS1202 at Xp22.11-p22.2.

Chromosome Mapping↗

Survey of staphylococcal enterotoxin genes, exfoliative toxin genes, and toxic shock syndrome toxin 1 gene in non-Staphylococcus aureus species.

The aim of this study was to analyze the presence of staphylococcal exotoxin genes in staphylococci other than Staphylococcus aureus. Whereas for Staphylococcus aureus a large spectrum of different exotoxins responsible for toxin-mediated diseases has been described, only few and conflicting data are available regarding toxin production in all other staphylococcal species. A collection of clinical non-Staphylococcus aureus staphylococcal isolates were systematically screened for the presence of genes for toxic shock syndrome toxin 1, exfoliative toxins, and classical enterotoxins by using multiplex polymerase chain reaction enzyme immunoassays. In a total of 461 isolates of 18 different (sub)species derived from clinical specimens, no toxin gene sequences were amplified. The results indicate that the occurrence of toxin genes involved in staphylococcal toxin-mediated diseases is at least very rare in human-derived isolates of non-Staphylococcus aureus species.

Bacterial Toxins↗

Upstream transcription factor 1 gene polymorphisms are associated with high antilipolytic insulin sensitivity and show gene-gene interactions.

Upstream transcription factor 1 (USF1) regulates the expression of many genes involved in lipid and glucose metabolism, among them genes regulating lipolysis. USF1 specifically regulates the expression of the hormone-sensitive lipase gene (HSL) in adipocytes and the hepatic lipase gene (LIPC) in the liver, which was found to be involved in liver fat accumulation. The usf1s1 C > T and usf1s2 G > A single-nucleotide polymorphisms (SNPs) in USF1 are associated with increased in vitro catecholamine-induced lipolysis in adipocytes. We investigated first whether SNPs in USF1 affect the lipolysis-suppressing action of insulin in vivo, and second, whether they interact with the -60C > G SNP in HSL on lipolysis and the -514C > T SNP in LIPC on liver fat. The usf1s1 C > T and usf1s2 G > A SNPs, together with the SNPs in HSL and LIPC, were determined in 407 Caucasians. Lipolysis was estimated as a change in free fatty acid (FFA) levels from baseline to 2 h of a 75-g oral glucose tolerance test (OGTT). Fifty-four subjects had data from a euglycemic hyperinsulinemic clamp with calculation of antilipolytic insulin sensitivity. Subjects carrying the minor alleles (T of usf1s1 and A of usf1s2) had lower 2 h FFA (p = 0.01) and a larger decrease in FFA concentrations during the OGTT (p = 0.02). Antilipolytic insulin sensitivity was higher in these individuals (p = 0.03). No interaction of the usf1s1 C > T and usf1s2 G > A SNPs with the -60C > G SNP in HSL on antilipolytic insulin sensitivity was detected. Liver fat, measured by (1)H magnetic resonance spectroscopy, was elevated only in subjects who were both homozygous for the major alleles of usf1s1 and usf1s2 and carriers of the T allele of the -514C > T SNP in LIPC (p = 0.01). In conclusion, subjects carrying the T allele of SNP usf1s1 and the A allele of SNP usf1s2 have a higher antilipolytic insulin sensitivity. Moreover, both SNPs may interact with the -514C > T SNP in LIPC to determine liver fat.

Adipocytes↗

Two genes, three messengers: hybrid transcript between a gene expressed at specific stages of T-cell and sperm maturation and an unrelated adjacent gene.

To identify new genes that are turned on following the expression of a pre-T-cell antigen receptor in early thymocytes, we developed a PCR-based subtractive approach that selects for mRNAs that are differentially expressed between thymocytes at the CD4(-)CD8(-) and CD4(+)CD8(+) stages. This approach led to the characterization of a cDNA, Tssn1, which is predominantly expressed in CD4(+)CD8(+) cells and at specific stages of spermatogenesis. We analyzed the structure of the Tssn1 gene in mouse and human and found that it is highly conserved. Of interest, Tssn1 is adjacent to an unrelated gene named 2310047L21Rik and gives rise to hybrid 2310047L21Rik--Tssn1transcripts. Therefore, this analysis offers insights into the critical steps that may precede the birth of new genes endowed with either compound functions or novel tissue distribution.

Amino Acid Sequence↗

Interaction between the gene 5 protein, gene 5 protein/single stranded fd DNA complex and gene 8 protein of the filamentous phage fd.

An affinity column consisting of gene 8 protein, the major coat protein of fd phage, bound to Sepharose was prepared. Isolated gene 5 protein/single stranded fd DNA complex was found to bind to this column and was eluted with fd phage single stranded fd DNA. pH changes, and 1 M CaCl2 were not effective in eluting the protein from the affinity column. Gene 5 protein/single stranded fd DNA complex from the crude extracts of fd-infected E. coli also bound to the column, as did isolated gene 5 protein; whereas fd single stranded DNA alone did not. These results may be relevant for the illucidation of the molecular events occurring in the early stages of fd phage assembly.

Arginine↗

Another putative heat-shock gene and aminoacyl-tRNA synthetase gene are located upstream from the grpE-like and dnaK-like genes in Chlamydia trachomatis.

The 4.1-kb sequence of genomic DNA located upstream from the Chlamydia trachomatis grpE-like and dnaK-like heat shock (HS) genes was determined. Another putative HS gene was located just 5' to grpE along with an inverted repeat (IR) sequence proposed to be involved in HS regulation. The overall organization of this locus in Chlamydia resembles that of Bacillus subtilis, rather than Escherichia coli. Two other open reading frames (ORFs) were found in the sequence, one of which has homology to aminoacyl-tRNA synthetases. The other ORF has no significant homology to reported genes. We also examined the codon usage bias for these newly identified chlamydial ORFs and for previously reported chlamydial genes, and found them to be different from E. coli.

Amino Acid Sequence↗

Association of polymorphisms in nicotinic acetylcholine receptor alpha 4 subunit gene (CHRNA4), mu-opioid receptor gene (OPRM1), and ethanol-metabolizing enzyme genes with alcoholism in Korean patients.

Findings obtained from several studies indicate that ethanol enhances the activity of alpha4beta2 neuronal nicotinic acetylcholine receptor and support the possibility that a polymorphism of the nicotinic acetylcholine receptor alpha4 subunit gene (CHRNA4) modulates enhancement of nicotinic receptor function by ethanol. To identify the association between the CfoI polymorphism of the CHRNA4 and alcoholism, we examined distribution of genotypes and allele frequencies in Korean patients diagnosed with alcoholism (n = 127) and Korean control subjects without alcoholism (n = 185) with polymerase chain reaction-restriction fragment length polymorphism methods. We were able to detect the association between the CfoI polymorphism of the CHRNA4 and alcoholism in Korean patients (genotype P = .023; allele frequency P = .047). The genotypes and allele frequencies of known polymorphisms in other alcoholism candidate genes, such as alcohol metabolism-related genes [alcohol dehydrogenase 2 (ADH2), aldehyde dehydrogenase 2 (ALDH2), alcohol dehydrogenase 3 (ADH3), and cytochrome P450 2E1 (CYP2E1)] and mu-opioid receptor gene (OPRM1), were studied. The polymorphisms of ADH2, ALDH2, and CYP2E1 were significantly different in Korean patients with alcoholism and Korean control subjects without alcoholism, but ADH3 and OPRM1 did not differ between the two groups.

Adult↗

Application of HSVtk suicide gene to X-SCID gene therapy: ganciclovir treatment offsets gene corrected X-SCID B cells.

Recently, a serious adverse effect of uncontrolled clonal T cell proliferation due to insertional mutagenesis of retroviral vector was reported in X-SCID gene therapy clinical trial. To offset the side effect, we have incorporated a suicide gene into therapeutic retroviral vector for selective elimination of transduced cells. In this study, B-cell lines from two X-SCID patients were transduced with bicistronic retroviral vector carrying human gamma c chain cDNA and Herpes simplex virus thymidine kinase gene. After confirmation of functional reconstitution of the gamma c chain, the cells were treated with ganciclovir (GCV). The gamma c chain positive cells were eliminated under low concentration without cytotoxicity on untransduced cells and have not reappeared at least for 5 months. Furthermore, the gamma c chain transduced cells were still sensitive to GCV after five months. These results demonstrated the efficacy of the suicide gene therapy although further in vivo studies are required to assess feasibility of this approach in clinical trial.

Antiviral Agents↗

Candidate gene association studies and evidence for gene-by-gene interactions.

Candidate gene studies in asthma are a powerful and valuable tool in asthma genetics. Although the quality of small-scale, freely associating studies has been questionable, increasingly serious efforts are made to establish, replicate, and verify association results. Association studies may help us to better understand the mechanisms underlying asthma. They may create hypotheses and help to direct functional studies to targets that are likely to give valuable results. However, they should not be over-interpreted; only biologic proof can verify associations between genetic variations and a certain disease outcome. The insight that gene-by-gene and gene-by-environment interactions may be crucial for understanding and pinpoint the complex mechanisms of genetic regulation of multifactorial diseases has gained momentum in the last years when technical improvement allowed for the effective genotyping and analysis of great numbers of polymorphisms in large populations. It can be expected that from this area of research new and exciting results will follow soon.

Asthma↗

Glutathione S-transferase M1 gene but not insulin-like growth factor-2 gene or epidermal growth factor gene is associated with prostate cancer.

Prostate cancer is the most common urologic malignancy involving multiple factors. There is evidence that suggests that detoxification enzymes and growth factors may play a role in the formation of prostate cancer. Our aim was to investigate whether polymorphisms of glutathione S-transferase M1 (GST M1), insulin-like growth factor-2 (IGF-2), and epidermal growth factor (EGFR) genes could be used as genetic markers for risk of prostate cancer. In this study, we compared the frequency of the polymorphisms of GST M1, IGF-2, and EGFR genes among 96 patients with prostate cancer and 121 healthy male volunteers from the same geographic area (age, older than 60 years). There was significant difference in the GST M1 genotype between the prostate cancer group and the control group (P=0.042). The GST M1 null genotype was significantly higher in the cancer group (59.4%) than in the control group (45.5%). However, our study did not reveal a significant association between prostate cancer and the distribution of the IGF-2 or EGFR genotypes. This study suggests that the GST M1 gene, but not the IGF-2 or the EGFR genes, may be a risk factor of developing prostate cancer in Taiwan.

Aged↗

Chromosomal localization, gene structure and transcription pattern of the ORFX gene, a homologue of the MHC-linked RING3 gene.

We have mapped the human ORFX gene to chromosome 9q34 and determined its complete gene structure. Comparison with RING3, the human MHC-linked homologue on 6p21.3, shows the two gene structures to be highly conserved but with an approximate threefold expansion in the ORFX introns. RING3 and ORFX are found to be ubiquitously expressed in human adult and foetal tissues. Evidence suggests that the two genes may have arisen from an ancient duplication in a common ancestral chromosome.

Adult↗

Quantitative assessment of sense and antisense transcripts from genes involved in antigenic variation (vsp genes) and encystation (cwp 1 gene) of Giardia lamblia clone GS/M-83-H7.

Antigenic variation of the intestinal protozoan parasite Giardia lamblia is caused by an exchange of the parasite's variant surface protein (VSP) coat. Many investigations on antigenic variation were performed with G. lamblia clone GS/M-83-H7 which produces surface antigen VSP H7. To generate novel information on giardial vsp gene transcription, vsp RNA levels were assessed by quantitative reverse transcription-(RT)-PCR in both axenic VSP H7-type trophozoites and subvariants obtained after negative selection of GS/M-83-H7 trophozoites by treatment with a cytotoxic, VSP H7-specific monoclonal antibody. Our investigation was not restricted to the assessment of the sense vsp transcript levels but also included an approach aimed at the detection of complementary antisense vsp transcripts within the two trophozoite populations. We found that sense vsp H7 RNA predominated in VSP H7-type trophozoites while sense RNA from only one (vsp IVg) of 8 subvariant vsp genes totally analysed predominated in subvariant-type trophozoites. Interestingly, the two trophozoite populations exhibited a similar relative distribution regarding the vsp H7 and vsp IVg antisense RNA molecules. An analogous sense versus antisense RNA pattern was also observed when the transcripts of gene cwp 1 (encoding cyst wall protein 1) were investigated. Here, both types of RNA molecules only appeared after cwp 1 had been induced through in vitro encystation of the parasite. These findings for the first time demonstrated that giardial antisense RNA production did not occur in a constitutive manner but was directly linked to complementary sense RNA production after activation of the respective gene systems.

Animals↗

The Small RNA gene activator protein, SphI postoctamer homology-binding factor/selenocysteine tRNA gene transcription activating factor, stimulates transcription of the human interferon regulatory factor-3 gene.

Many small nuclear RNA gene promoters are activated by SphI postoctamer homology (SPH)-binding factor/selenocysteine tRNA gene transcription activating factor (SBF/Staf). Whereas this transcription factor was initially identified by its ability to bind to SPH elements in such promoters, it was more recently shown to have the capacity to activate transcription of a synthetic mRNA gene promoter through a distinct activation domain. Here, we show that the human interferon regulatory factor-3 (IRF-3) gene promoter contains a functional SPH element that is bound by SBF/Staf in vitro and in transfected cells.

Amino Acid Motifs↗

Gene-gene, gene-environment & multiple interactions in colorectal cancer.

This review comprehensively evaluates the influence of gene-gene, gene-environment and multiple interactions on the risk of colorectal cancer (CRC). Methods of studying these interactions and their limitations have been discussed herein. There is a need to develop biomarkers of exposure and of risk that are sensitive, specific, present in the pathway of the disease, and that have been clinically tested for routine use. The influence of inherited variation (polymorphism) in several genes has been discussed in this review; however, due to study limitations and confounders, it is difficult to conclude which ones are associated with the highest risk (either individually or in combination with environmental factors) to CRC. The majority of the sporadic cancer is believed to be due to modification of mutation risk by other genetic and/or environmental factors. Micronutrient deficiency may explain the association between low consumption of fruit/vegetables and CRC in human studies. Mitochondrial modulation by dietary factors influences the balance between cell renewal and death critical in colon mucosal homeostasis. Both genetic and epigenetic interactions are intricately dependent on each other, and collectively influence the process of colorectal tumorigenesis. The genetic and environmental interactions present a good prospect and a challenge for prevention strategies for CRC because they support the view that this highly prevalent cancer is preventable.

Cocarcinogenesis↗

Multifactor dimensionality reduction software for detecting gene-gene and gene-environment interactions.

MOTIVATION: Polymorphisms in human genes are being described in remarkable numbers. Determining which polymorphisms and which environmental factors are associated with common, complex diseases has become a daunting task. This is partly because the effect of any single genetic variation will likely be dependent on other genetic variations (gene-gene interaction or epistasis) and environmental factors (gene-environment interaction). Detecting and characterizing interactions among multiple factors is both a statistical and a computational challenge. To address this problem, we have developed a multifactor dimensionality reduction (MDR) method for collapsing high-dimensional genetic data into a single dimension thus permitting interactions to be detected in relatively small sample sizes. In this paper, we describe the MDR approach and an MDR software package. RESULTS: We developed a program that integrates MDR with a cross-validation strategy for estimating the classification and prediction error of multifactor models. The software can be used to analyze interactions among 2-15 genetic and/or environmental factors. The dataset may contain up to 500 total variables and a maximum of 4000 study subjects. AVAILABILITY: Information on obtaining the executable code, example data, example analysis, and documentation is available upon request. SUPPLEMENTARY INFORMATION: All supplementary information can be found at http://phg.mc.vanderbilt.edu/Software/MDR.

Algorithms↗