The use of new cell substrates for the development of biologicals, particularly tumorigenic and tumor-derived cell lines, can pose a major regulatory challenge due to safety concerns related to the presence of novel viruses, latent and occult viruses including oncogenic viruses, and endogenous retroviruses, since these may not be detected by the currently recommended conventional assays. This report is a summary of our laboratory's experiences using advanced nucleic acid-based technologies to evaluate a Madin-Darby canine kidney (MDCK) cell line and the insect Sf9 cell line derived from Spodoptera frugiperda, and presents some ongoing efforts to address the challenges of novel virus detection.
View Article and Find Full Text PDFAdvanced nucleic acid-based technologies are powerful research tools for novel virus discovery but need to be standardized for broader applications such as virus detection in biological products and clinical samples. We have used well-characterized retrovirus stocks to evaluate the limit of detection (LOD) for broad-range PCR with electrospray ionization mass spectrometry (PCR/ESI-MS or PLEX-ID), RT-PCR assays, and virus microarrays. The results indicated that in the absence of background cellular nucleic acids, PLEX-ID and RT-PCR had a similar LOD for xenotropic murine retrovirus-related virus (XMRV; 3.
View Article and Find Full Text PDFUnlabelled: The Sf9 cell line, derived from Spodoptera frugiperda, is used as a cell substrate for biological products, and no viruses have been reported in this cell line after extensive testing. We used degenerate PCR assays and massively parallel sequencing (MPS) to identify a novel RNA virus belonging to the order Mononegavirales in Sf9 cells. Sequence analysis of the assembled virus genome showed the presence of five open reading frames (ORFs) corresponding to the genes for the N, P, M, G, and L proteins in other rhabdoviruses and an unknown ORF of 111 amino acids located between the G- and L-protein genes.
View Article and Find Full Text PDFProstate Cancer Prostatic Dis
June 2012
Background: The majority of prostate cancers (CaP) are detected in early stages with uncertain prognosis. Therefore, an intensive effort is underway to define early predictive markers of CaP with aggressive progression characteristics.
Methods: In order to define such prognostic markers, we performed comparative analyses of transcriptomes of well- and poorly differentiated (PD) tumor cells from primary tumors of patients (N=40) with 78 months of mean follow-up after radical prostatectomy.
Porcine circovirus type 1 (PCV1) is highly prevalent in swine and was recently reported in some rotavirus vaccines. Since animal-derived raw materials, such as cells, trypsin, and serum, can be a major source of introducing virus contamination in biological products, we have investigated PCV1 in several cell lines obtained from ATCC that have broad use in research, diagnostics, or vaccine development. It is expected that these cell lines have been exposed to bovine and porcine viruses during their establishment and passage history due to the use of serum and trypsin that was not qualified according to current testing guidances or processed using new virus-inactivation methods.
View Article and Find Full Text PDFCancer Biol Ther
February 2011
Androgen dependent induction of the ETS related gene (ERG) expression in more than half of all prostate cancers results from gene fusions involving regulatory sequence of androgen regulated genes (i.e. TMPRSS2, SLC45A3 and NDRG1) and protein coding sequence of the ERG.
View Article and Find Full Text PDFObjectives: To better understand the gene expression patterns in tumor-associated stroma, laser-capture-microdissections from clinical specimens were analyzed by genome-wide-expression microarray technology. The epithelial-stromal interaction plays a critical role in prostate development, reactive changes, and tumorigenesis. Diverse microarray technologies have been used to characterize the molecular changes in prostate cancer.
View Article and Find Full Text PDFCurcumin (diferuloylmethane) is the major active component of turmeric and is being actively investigated for its anti-cancer properties. To better understand the biological mechanisms of the chemopreventive potential of curcumin in prostate cancer, we have evaluated curcumin regulated transcriptome in prostate cancer cells. Hierarchical clustering methods and functional classification of the Curcumin-Gene Expression Response (Cu-GER) showed temporal co-regulation of genes involved in oxidative stress response and growth signaling pathways.
View Article and Find Full Text PDFThe high prevalence of TMPRSS2-ERG rearrangements ( approximately 60%) in prostate cancer (CaP) leads to androgenic induction of the ETS-related gene (ERG) expression. However, the biological functions of ERG overexpression in CaP remain to be understood. ERG knockdown in TMPRSS2-ERG expressing CaP cells induced striking morphological changes and inhibited cell growth both in cell culture and SCID mice.
View Article and Find Full Text PDFPurpose: Alterations of the androgen receptor (AR)-mediated signaling through numerous mechanisms are increasingly recognized in prostate cancer (CaP) progression. We hypothesized that the assessment of well-defined AR transcriptional targets (e.g.
View Article and Find Full Text PDFFormalin-fixed paraffin-embedded (FFPE) prostate specimens are rich sources of molecular pathological information. However, FFPE-based microarray analysis of tissue samples may be hampered by the degradation and chemical alteration of RNA molecules due to the preservation procedure. In this report, we employed a probe analyses of Affymetrix oligonucleotide arrays at individual probe level to compensate for the potential loss of gene identifications associated with compromised mRNA quality in FFPE preparations.
View Article and Find Full Text PDFBackground: Cancer cells gain selection advantages by the coordinated silencing of protective and by the activation of cell proliferation/cell survival genes. Evaluations of epithelial cell transcriptome of benign and malignant prostate glands by laser capture microdissection (LCM) identified Lactotransferrin (LTF) as the most significantly downregulated gene in prostate cancer (CaP) cells (p < 10(-6)). Frequent downregulation, significant association of LTF with PSA recurrence-free survival in CaP patients and the established anti-tumorigenic effects of LTF in experimental cancer models have provided impetus to evaluate LTF expression features and mechanisms in CaP specimens.
View Article and Find Full Text PDFThe majority of prostate epithelial cell lines stably expressing wild-type (wt) or mutant (mt) androgen receptor (AR) are derived from metastatic prostate cancers. Therefore, the wt AR-expressing RC-165N/human telomerase reverse transcriptase (hTERT) cell line derived from the benign prostate tissue of an African-American patient provides a unique opportunity to assess the functional status of AR in a cellular context not studied before. Although androgen-induced expression of known androgen responsive genes such as PMEPA1, and NDRG1 was observed in RC-165N/hTERT, this cell line expresses prostate-specific antigen (PSA) at significantly lower levels.
View Article and Find Full Text PDFHuman prostatic acid phosphatase (PAcP) was used as a valuable surrogate marker for monitoring prostate cancer prior to the availability of prostate-specific antigen (PSA). Even though the level of PAcP is increased in the circulation of prostate cancer patients, its intracellular level and activity are greatly diminished in prostate cancer cells. Recent advances in understanding the function of the cellular form of PAcP (cPAcP) have shed some light on its role in prostate carcinogenesis, which may have potential applications for prostate cancer therapy.
View Article and Find Full Text PDFTranscription factors encoded by the ETS family of genes are central in integrating signals that regulate cell growth and differentiation, stress responses, and tumorigenesis. This study, analysing laser microdissected paired benign and malignant prostate epithelial cells from prostate cancer (CaP) patients (n=114; 228 specimen) by GeneChip and quantitative real-time RT-PCR, identifies ETS-related gene (ERG), a member of the ETS transcription factor family, as the most frequently overexpressed proto-oncogene in the transcriptome of malignant prostate epithelial cells. Combined quantitative expression analysis of ERG with two other genes commonly overexpressed in CaP, AMACR and DD3, revealed overexpression of at least one of these three genes in virtually all CaP specimen (54 of 55).
View Article and Find Full Text PDFThe chromosome of Bacteroides fragilis strain YCH46 was shown to be a single circular DNA molecule of about 5.3 Mb having 16 NotI, seven AscI, and six I-CeuI sites. A physical map of the chromosome was constructed by four independent experimental approaches: linking clone analysis, cross-Southern hybridization, partial restriction digestion, and two-dimensional pulsed-field gel electrophoresis.
View Article and Find Full Text PDFThe early human immunodeficiency virus (HIV) accessory protein Nef makes an important contribution to virulence, but the mechanisms by which Nef influences pathogenesis remain unclear. Many well-studied effects of Nef, like CD4 and class I MHC downregulation, occur posttranslationally. However, Nef has the potential to affect gene expression by interfering with cell signaling pathways and by virtue of structural features such as the Pro-X-X-Pro motif, which may interact with src homology region-3 domains of src-like kinases.
View Article and Find Full Text PDFA Bacillus subtilis plasmid encoding a green fluorescence protein gene (gfp) was constructed. The fluorescence of B. subtilis colonies having this plasmid on agar plates was so high that they could be readily discerned visually under UV light.
View Article and Find Full Text PDFThe chromosomal DNAs of nine strains of seven Bacteroides species including B. fragilis, the type species of the genus Bacteroides, were digested with rare-cutting restriction enzymes I-Ceu I, Not I, and Asc I and analysed by pulsed-field gel electrophoresis. The genome sizes of B.
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