Real-time RT-PCR Analysis (real-time + rt-pcr_analysis)

Distribution by Scientific Domains

Kinds of Real-time RT-PCR Analysis

  • quantitative real-time rt-pcr analysis


  • Selected Abstracts


    Multiple promoter elements required for leukemia inhibitory factor-stimulated M2 muscarinic acetylcholine receptor promoter activity

    JOURNAL OF NEUROCHEMISTRY, Issue 4 2006
    George S. Laszlo
    Abstract Treatment of neuronal cells with leukemia inhibitory factor (LIF) results in increased M2 muscarinic acetylcholine receptor promoter activity. We demonstrate here that multiple promoter elements mediate LIF stimulation of M2 gene transcription. We identify a LIF inducible element (LIE) in the M2 promoter with high homology to a cytokine-inducible ACTG-containing sequence in the vasoactive intestinal peptide promoter. Mutagenesis of both a STAT (signal transducers and activators of transcription) element and the LIE in the M2 promoter is required to attenuate stimulation of M2 promoter activity by LIF completely. Mobility shift assays indicate that a LIF-stimulated complex binds to a 70 base pair M2 promoter fragment. Furthermore, a STAT element within this fragment can bind to LIF-stimulated nuclear STAT1 homodimers in vitro. Mutagenesis experiments show that cytokine-stimulated activation of M2 promoter activity requires tyrosine residues on glycoprotein 130 (gp130) that are also required for both STAT1 and STAT3 activation. Dominant negative STAT1 or STAT3 can block LIF-stimulated M2 promoter activity. Real-time RT-PCR analysis indicates that LIF-stimulated induction of M2 mRNA is partially dependent on protein synthesis. These results show that regulation of M2 gene transcription in neuronal cells by LIF occurs through a complex novel mechanism that is dependent on LIE, STAT and de novo protein synthesis. [source]


    Altered Cbfal expression and biomineralization in an osteosarcoma cell line

    JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 2 2004
    H. Perinpanayagam
    Abstract Osteoblast differentiation and expression are regulated by Cbfal transcription factors. Recent evidence suggests that Cbfal may also regulate bone mineralization. The purpose of this study was to characterize Cbfal expression in relation to mineralization in rat UMR106-01 osteoblastic cell cultures. UMR106-01 BSP cultures consistently form bone-like mineral, whereas the UI subclone mineralize gradually. BSP and UI cultures were grown for 48 h and then treated with ,-glycerophosphate. BSP cultures had alizarin red stained calcifications and mineral-like deposits within 24 h of phosphate. Atomic absorption spectroscopy measured significantly (P < 0.0001) more calcium in the phosphate-treated BSP cultures than in the UI. Cbfal message was detected in the BSP and UI cultures, but the Cbfal N-terminal isoform was deficient in UI and appeared to be up-regulated in the phosphate-treated BSP cultures. Cbfal protein levels were also reduced in the UI. DNA sequence from the RT-PCR products was utilized to design Taqman Real-time RT-PCR reagents. Quantitative Real-time RT-PCR analysis showed that Cbfal mRNA levels relative to endogenous 18 s rRNA were lower in the slower mineralizing UI cultures. Furthermore, the Cbfal N-terminal isoform mRNA levels were significantly (P < 0.001) lower in the slower mineralizing cultures. Transfection with Cbfal or isoform antisense caused a significant (P < 0.001) reduction in mineralization. Therefore, Cbfal expression may be associated with bone-like mineral formation in rat UMR106-01 osteoblastic cell cultures. © 2003 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved. [source]


    Regulation of prostaglandin synthesis in ovaries of sexually-mature zebrafish (Danio rerio)

    MOLECULAR REPRODUCTION & DEVELOPMENT, Issue 11 2009
    Andrea L. Lister
    This study investigates the regulation of prostaglandin (PG) synthesis in the ovaries of sexually-mature zebrafish (Danio rerio). We examined the ovarian expression of genes within the arachidonic acid (AA) pathway, and the ovarian levels of 17,,20,-dihydroxy-4-pregnen-3-one (17,,20,-P), 17,-estradiol (E2), and PGF2, in spawning and nonspawning fish during the ovulatory cycle. Real-time RT-PCR analysis revealed that the expression levels of cytosolic phospholipase A2 (cpla2) and cyclooxygenases (COX)-2 (ptgs2) in ovarian fragments and in isolated full-grown follicles of spawning fish were highest at 6:00 when ovulation was expected to occur. In nonspawning fish, cpla2 expression levels declined over time while ptgs2 expression displayed the same temporal pattern as in spawning fish. Elevated levels of 17,,20,-P in the spawning fish occurred at 3:30, but there were no changes in the nonspawning fish. In other studies conducted to investigate the hormonal regulation of AA pathway genes, fish exposed via the water for 24 or 96,hr to 17,,20,-P or E2 exhibited reduced ovarian expression levels of COX-1 (ptgs1) and PG E synthase-2 (ptgsl), and E2 reduced the expression of cpla2. Injection of human chorionic gonadotropin (hCG) (100,IU) led to increased expression levels of cpla2 and ptgs2 at 2 and 18,hr post-treatment, but consistently reduced ptgs1 and ptgsl expression. In these fish, ovarian levels of 17,,20,-P were elevated at all time points and PGF2, levels in the hCG-treated group were significantly higher than the control fish at 18,hr. Collectively, these in vivo results suggest that gonadotropins and steroids are involved in the regulation of the AA pathway in ovarian follicles of zebrafish. Mol. Reprod. Dev. 76: 1064,1075, 2009. © 2009 Wiley-Liss, Inc. [source]


    The expression of osteopontin is increased in vessels with blood,brain barrier impairment

    NEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 2 2008
    Y. Iwanaga
    Aims: We previously reported that the blood,brain barrier (BBB) function was deteriorated in vessels located along hippocampal fissures in stroke-prone spontaneously hypertensive rats (SHRSP). In this study, we examined changes of gene expression in the BBB-damaged vessels of SHRSP. Methods: Vascular samples were microdissected from the hippocampi of SHRSP and Wistar-Kyoto (WKY) as a control and the difference in gene expression between the BBB-damaged vessels in SHRSP and vessels without BBB damage in WKY was examined by a microarray. The differences in gene and protein expression between brain tissues in the two strains of rats were examined using real-time quantitative reverse transcriptase-polymerase chain reaction (RT-PCR), Western blotting and immunohistochemistry. Results: The microarray assay revealed that the ratio of osteopontin gene expression in the vascular tissue of the hippocampi of SHRSP to that of WKY was the highest among 8435 genes. Real-time RT-PCR analysis revealed that the gene expression of osteopontin was significantly increased in the hippocampal samples of SHRSP compared with that in the hippocampal samples of WKY rats or with that in the cortical samples of SHRSP. Immunohistochemical and Western blot analyses showed that the osteopontin protein expression was seen in perivascular ED1-positive macrophages/microglial cells located around hippocampal fissures and significantly increased in the hippocampi of SHRSP compared with that of WKY. Conclusions: These findings indicate that the expression of osteopontin is increased in BBB-damaged vessels in hypertensive SHRSP compared with that in vessels without BBB impairment in WKY rats, suggesting a role for osteopontin in BBB function. [source]


    Novel cytochrome P450s, CYP6BB1 and CYP6P10, from the salt marsh mosquito Aedes sollicitans (Walker) (Diptera: Culicidae)

    ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY (ELECTRONIC), Issue 3 2008
    Shaoming Huang
    Abstract Based on the conserved heme-binding region and the charge pair consensus of insect cytochrome P450s, two novel full-length P450 cDNAs, CYP6BB1 and CYP6P10, were cloned from the salt marsh mosquito Aedes sollicitans (Walker). CYP6BB1 and CYP6P10 had open reading frames of 1,518 and 1,521 nucleotides encoding 506 and 507 amino acid residue proteins, respectively. Several alleles with amino acid substitutions were found both in CYP6BB1 and CYP6P10. The deduced proteins are typical microsomal P450s sharing signature sequences with other insect CYP6 P450s. Sequence analysis showed that both CYP6BB1 and CYP6P10 shared highest sequence identities with P450 CYP6P4, 56% and 65%, respectively. Phylogenetic analysis showed both CYP6BB1 and CYP6P10 were grouped into the clade containing several P450s from subfamily CYP6P. Real-time RT-PCR analysis showed CYP6BB1 but not CYP6P10 transcription in females was significantly increased 24 h after a blood meal. Neither CYP6BB1 nor CYP6P10 were life stage or gender specific. Protein expression experiments are needed to determine the functions of these proteins. Arch. Insect Biochem. Physiol. 2007. © 2007 Wiley-Liss, Inc. [source]


    Rhabdomyosarcoma: Value of myogenin expression analysis and molecular testing in diagnosing the alveolar subtype

    CANCER, Issue 12 2004
    An analysis of 109 paraffin-embedded specimens
    Abstract BACKGROUND Identification of the alveolar subtype of rhabdomyosarcoma (ARMS) is important, because the poor prognosis associated with this subtype necessitates a modified therapeutic regimen. At present, ARMS diagnoses are made on the basis of histologic findings and the extent of myogenin immunopositivity. Nonetheless, the absence of an alveolar pattern in the solid variant, the low degree of differentiation in certain embryonal rhabdomyosarcomas (ERMS), and the increasing use of microbiopsy samples make the diagnosis of ARMS somewhat difficult. Two specific translocations have been found in ARMS, and fusion transcripts can be detected by reverse transcriptase,polymerase chain reaction (RT-PCR) analysis of paraffin-embedded tissue (PET). METHODS To assess the value of myogenin staining and molecular testing in the diagnosis of rhabdomyosarcoma, the authors examined 109 rhabdomyosarcoma samples (45 ARMS samples and 64 ERMS samples). Real-time RT-PCR analysis of PET was performed in all 109 rhabdomyosarcomas, and RT-PCR analysis of frozen material was performed in 24 cases. RESULTS PAX fusion transcripts were present in 44 cases (39 ARMS and 5 ERMS) and absent in 52 cases (2 ARMS and 50 ERMS). In 13 cases (4 ARMS and 9 ERMS), the results were not interpretable. Results were concordant between paired frozen and fixed tumor samples. All 35 interpretable ERMS samples that contained < 50% myogenin-positive cells failed to yield detectable PAX fusion transcripts. Of the 61 interpretable tumor samples (41 ARMS and 20 ERMS) that contained > 50% myogenin-positive cells, 44 (39 ARMS and 5 ERMS) yielded detectable PAX fusion transcripts. CONCLUSIONS The current study demonstrates that molecular detection of PAX fusion transcripts via real-time RT-PCR analysis of PET is a sensitive and specific method for the diagnosis of ARMS and that immunohistochemical analysis of myogenin expression can be used to select cases for such molecular testing. Although RT-PCR analysis appears not to possess diagnostic value in tumors with < 50% tumor cell immunopositivity, it is strongly recommended for the diagnosis of tumors containing > 50% myogenin-positive cells. Cancer 2004. © 2004 American Cancer Society. [source]


    Enhanced expression of B7-1, B7-2, and intercellular adhesion molecule 1 in sinusoidal endothelial cells by warm ischemia/reperfusion injury in rat liver

    HEPATOLOGY, Issue 4 2001
    Naosuke Kojima
    To elucidate a role of costimulatory molecule and cell adhesion molecule in hepatic ischemia/reperfusion injury, we examined an alteration in B7-1 (CD80), B7-2 (CD86), and intercellular adhesion molecule 1 (ICAM-1; CD54) expression in the rat liver after warm ischemia/reperfusion injury. To induce hepatic warm ischemia in a rat model, both portal vein and hepatic artery entering the left-lateral and median lobes were occluded by clamping for 30 minutes or 60 minutes, and then reperfused for 24 hours. B7-1, B7-2, and ICAM-1 expressions in the liver were analyzed by immunofluorescence staining and real-time reverse transcription polymerase chain reaction (RT-PCR). Although B7-1 and B7-2 expressions were at very low levels in the liver tissues from normal or sham-operated control rats, both B7-1 and B7-2 expressions were enhanced at protein and messenger RNA (mRNA) levels in the affected, left lobes after warm ischemia/reperfusion. ICAM-1 protein and mRNA were constitutively expressed in the liver of normal and sham-operated control rats, and further up-regulated after warm ischemia/reperfusion. Localization of increased B7-1, B7-2, and ICAM-1 proteins, as well as von Willebrand factor as a marker protein for endothelial cells, was confined by immunofluorescence staining to sinusoidal endothelial cells in hepatic lobules. Data from quantitative real-time RT-PCR analysis revealed that B7-1 and B7-2 mRNA levels were elevated in hepatic lobes after warm ischemia/reperfusion (5.13- and 52.9-fold increase, respectively), whereas ICAM-1 mRNA expression was rather constitutive but further enhanced by warm ischemia/reperfusion (4.24-fold increase). These results suggest that hepatic sinusoidal endothelial cells play a pivotal role as antigen-presenting cells by expressing B7-1 and B7-2 in warm hepatic ischemia/reperfusion injury, and that B7-1 and/or B7-2 might be the primary target to prevent early rejection and inflammatory reactions after hepatic ischemia/reperfusion injury associated with liver transplantation. [source]


    HPV related VIN: Highly proliferative and diminished responsiveness to extracellular signals

    INTERNATIONAL JOURNAL OF CANCER, Issue 4 2007
    Lindy A.M. Santegoets
    Abstract Vulvar intraepithelial neoplasia (VIN) is a premalignant disorder caused by human papillomaviruses. Basic knowledge about the molecular pathogenesis of VIN is sparse. Therefore, we have analyzed the gene expression profile of 9 VIN samples in comparison to 10 control samples by using genome wide Affymetrix Human U133A plus2 GeneChips. Results were validated by quantitative real-time RT-PCR analysis and immunostaining of a few representative genes (TACSTD1, CCNE2, AR and ESR1). Significance analysis of microarrays (SAM) showed that 1,497 genes were differentially expressed in VIN compared to controls. By analyzing the biological processes affected by the observed differences, we found that VIN appears to be a highly proliferative disease; many cyclins (CCNA, CCNB and CCNE) and almost all prereplication complex proteins are upregulated. Thereby, VIN does not seem to depend for its proliferation on paracrine or endocrine signals. Many receptors (for example ESR1 and AR) and ligands are downregulated. Furthermore, although VIN is not an invasive disease, the inhibition of expression of a marked number of cell,cell adhesion molecules seems to indicate development towards invasion. Upon reviewing apoptosis and angiogenesis, it was observed that these processes have not become significantly disregulated in VIN. In conclusion: although VIN is still a premalignant disease, it already displays several hallmarks of cancer. © 2007 Wiley-Liss, Inc. [source]


    Identification of a novel human tissue factor splice variant that is upregulated in tumor cells,

    INTERNATIONAL JOURNAL OF CANCER, Issue 7 2006
    Hitendra S. Chand
    Abstract Tissue factor (TF) is a transmembrane glycoprotein that serves as the prime initiator of blood coagulation and plays a critical role in thrombosis and hemostasis. In addition, a variety of tumor cells overexpress cell-surface TF, which appears to be important for tumor angiogenesis and metastasis. To elucidate the mechanism involved in the upregulation of TF in human tumor cells, a comprehensive analysis of TF mRNA from various normal and tumor cells was performed. The results of these studies indicate that, in addition to possessing a normal full-length TF transcript and minor levels of an alternatively spliced transcript known as alternatively-spliced tissue factor (asTF) (Bogdanov et al., Nat Med 2003;9:458,62), human tumor cells express additional full-length TF transcripts that are also generated by alternative splicing. Reverse transcriptase-polymerase chain reaction (RT-PCR) and 5,-rapid amplification of cDNA ends- (5,-RACE) based analyses of cytoplasmic RNA from normal and tumor cells revealed that there is alternative splicing of the first intron between exon I and exon II resulting in 2 additional TF transcripts. One of the transcripts has an extended exon I with inclusion of most of the first TF intron (955 bp), while the second transcript is formed by the insertion of a 495 bp sequence, referred to as exon IA, derived from an internal sequence of the first intron. The full length TF transcript with alternatively spliced novel exon IA, referred to as alternative exon 1A-tissue factor (TF-A), represented ,1% of the total TF transcripts in normal cells, but constituted 7,10% of the total TF transcript in tumor cells. Quantitative real-time RT-PCR analysis indicated that cultured human tumor cells contain 10,25-fold more copy numbers of TF-A in comparison to normal, untransformed cells. We propose that high-level expression of the novel TF-A transcript, preferentially in tumor cells, may have utility in the diagnosis and staging of a variety of solid tumors. © 2005 Wiley-Liss, Inc. [source]


    Characterization of human fetal osteoblasts by microarray analysis following stimulation with 58S bioactive gel-glass ionic dissolution products

    JOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 2 2006
    Ioannis Christodoulou
    Abstract Bioactive glasses dissolve upon immersion in culture medium, releasing their constitutive ions in solution. There is evidence suggesting that these ionic dissolution products influence osteoblast-specific processes. Here, we investigated the effect of 58S sol,gel-derived bioactive glass (60 mol % SiO2, 36 mol % CaO, 4 mol % P2O5) dissolution products on primary osteoblasts derived from human fetal long bone explant cultures (hFOBs). We used U133A human genome GeneChip® oligonucleotide arrays to examine 22,283 transcripts and variants, which represent over 18,000 well-substantiated human genes. Hybridization of samples (biotinylated cRNA) derived from monolayer cultures of hFOBs on the arrays revealed that 10,571 transcripts were expressed by these cells, with high confidence. These included transcripts representing osteoblast-related genes coding for growth factors and their associated molecules or receptors, protein components of the extracellular matrix (ECM), enzymes involved in degradation of the ECM, transcription factors, and other important osteoblast-associated markers. A 24-h treatment with a single dosage of ionic products of sol,gel 58S dissolution induced the differential expression of a number of genes, including IL-6 signal transducer/gp130, ISGF-3/STAT1, HIF-1 responsive RTP801, ERK1 p44 MAPK (MAPK3), MAPKAPK2, IGF-I and IGFBP-5. The over 2-fold up-regulation of gp130 and MAPK3 and down-regulation of IGF-I were confirmed by real-time RT-PCR analysis. These data suggest that 58S ionic dissolution products possibly mediate the bioactive effect of 58S through components of the IGF system and MAPK signaling pathways. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006 [source]


    Hepatocyte Growth Factor Contributes to Fracture Repair by Upregulating the Expression of BMP Receptors,

    JOURNAL OF BONE AND MINERAL RESEARCH, Issue 10 2005
    Yuuki Imai MD
    Abstract Hepatocyte growth factor (HGF) is activated and the expression of BMP receptors (BMPRs) is induced around the fracture site during the early phase of fracture repair. HGF facilitates the expression of BMPRs in mesenchymal cells. This study suggests that HGF contributes to fracture repair by inducing the expression of BMPRs. Introduction: The precise mechanisms that control the upregulation of BMP, BMPRs, and other molecules involved in bone repair are not completely understood. In this study, we hypothesized that HGF, activated through the action of thrombin on the HGF activator, may enhance BMP action through the local induction of BMP or BMPRs. Materials and Methods: Callus samples from tibial fractures in mice were harvested for immunohistochemical analysis of HGF and phosphorylated c-Met, for in situ hybridization of BMPRs, and for real-time RT-PCR analysis for the expression of HGF, c-Met, and BMPRs. To study the changes in gene expression of BMPRs in response to HGF, C3H10T1/2 cells were cultured with or without HGF and harvested for real-time RT-PCR and for Western blot analysis. To evaluate the contribution of HGF to the biological action of BMP2, C3H10T1/2 cells and primary muscle-derived mesenchymal cells were precultured with HGF and cultured with BMP2. In addition, the expression of the luciferase gene linked to the Id1 promoter containing the BMP responsive element and alkaline phosphatase (ALP) activity were assayed. Results: Positive immunostaining of HGF and phosphorylated c-Met was detected around the fracture site at 1 day after the fracture was made. mRNA expression of BMPRs was increased 1 day after fracture and localized in mesenchymal cells at the fracture site. From an in vitro study, the expression of mRNA for BMPRs was elevated by treatment with HGF, but the expression of BMP4 did not change. Western blot analysis also showed the upregulation of BMPR2 by HGF treatment. The results from the luciferase and ALP assays indicated increased responsiveness to BMPs by treating with HGF. Conclusions: This study indicates that HGF is activated and expressed at the fracture site and that HGF induces the upregulation of BMPRs in mesenchymal cells. Furthermore, HGF may facilitate BMP signaling without altering the expression of BMP molecules. [source]


    Expression profiling reveals alternative macrophage activation and impaired osteogenesis in periprosthetic osteolysis

    JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 1 2008
    Panagiotis Koulouvaris
    Abstract Interactions between periprosthetic cells and prosthetic wear debris have been recognized as an important event in the development of osteolysis and aseptic loosening. Although the ability of wear debris to activate pro-inflammatory macrophage signaling has been documented, the full repertoire of macrophage responses to wear particles has not been established. Here, we examined the involvement of alternative macrophage activation and defective osteogenic signaling in osteolysis. Using real-time RT-PCR analysis of periprosthetic soft tissue from osteolysis patients, we detected elevated levels of expression of alternative macrophage activation markers (CHIT1, CCL18), chemokines (IL8, MIP1 ,) and markers of osteoclast precursor cell differentiation and multinucleation (Cathepsin K, TRAP, DC-STAMP) relative to osteoarthritis controls. The presence of cathepsin K positive multinuclear cells was confirmed by immunohistochemistry. Reduced expression levels of the osteogenic signaling components BMP4 and FGF18 were detected. Expression levels of TNF-,, IL-6, and RANKL were unchanged, while the anti-osteoclastogenic cytokine OPG was reduced in osteolysis patients, resulting in elevated RANKL:OPG ratios. In vitro studies confirmed the role of particulate debris in alternative macrophage activation and inhibition of osteogenic signaling. Taken together, these results suggest involvement in osteolysis of alternative macrophage activation, accompanied by elevated levels of various chemokines. Increased recruitment and maturation of osteoclast precursors is also observed, as is reduced osteogenesis. These findings provide new insights into the molecular pathogenesis of osteolysis, and identify new potential candidate markers for disease progression and therapeutic targeting. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:106,116, 2008 [source]


    Expression of N -methyl- D -aspartate (NMDA) and , -amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) GluR2/3 receptors in the developing rat pineal gland

    JOURNAL OF PINEAL RESEARCH, Issue 3 2005
    C. Kaur
    Abstract:, The expression of , -amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) type glutamate (GluR2/3) receptors and N -methyl- d -aspartate receptor subtype 1 (NMDAR1) was carried out by immunohistochemistry, double immunofluorescence and real-time RT-PCR analysis in the pineal glands of 1-day to 6-wk-old rats in the present study. GluR2/3 immunopositive cells were distributed throughout the pineal gland and showed branching processes in all age groups. The NMDAR1 immunoreactivity, however, was observed in fewer branched cells. A constitutive mRNA expression of NMDAR1, GluR2 and GluR3 was detected in the pineal glands of various ages and showed no significant difference between the age groups studied. Immunohistochemical and double immunofluorescence results showed that the GluR2/3 were mainly expressed and co-localized with OX-42-positive microglia/macrophages and the glial fibrillary acidic protein (GFAP)-positive astrocytes. Co-localization of NMDAR1 with OX-42- and GFAP-positive cells was much less. The expression of these receptors on the glial cells suggests that they may be involved in the development and growth of the pineal gland in the early postnatal period (1 day to 3 wk) and subsequently in the regulation of melatonin synthesis. [source]


    Possible role of the protein kinase C/CPI-17 pathway in the augmented contraction of human myometrium after gestation

    BRITISH JOURNAL OF PHARMACOLOGY, Issue 7 2003
    Hiroshi Ozaki
    Activation of protein kinase C (PKC) by phorbol 12,13-dibutylate (PDBu, 1 ,M) induced sustained contractions with no increase in [Ca2+]i in nonpregnant and pregnant human myometria. The contractile effects of PDBu in pregnant myometrium were much greater than those in nonpregnant myometrium, and the contractions in pregnant myometrium were accompanied by an increase in myosin light chain (MLC) phosphorylation at Ser19. The contraction induced by PDBu in pregnant myometrium was inhibited by the inhibitors of conventional PKC isoforms, bisindolylmaleimides and indolocarbazole, such as Go6976, Go6983, and Go6850 (1 ,M). LY333531 (1 ,M), a specific inhibitor of PKC,, also inhibited the PDBu-induced contraction in the pregnant myometrium. In the pregnant myometrium permeabilized with , -toxin, PDBu increased the contractions induced at fixed Ca2+ concentration (0.3 ,M) both in nonpregnant and pregnant myometria, indicating Ca2+ sensitization of contractile elements. Western immunoblot analysis indicated that pregnant myometrium contained PKC isozymes such as conventional PKC (,, ,, ,), novel PKC (,, ,, ,), and atypical PKC (, but not , and ,). RT-PCR and real-time RT-PCR analysis indicated that, among the conventional PKC, the levels of mRNA of , isoform in pregnant human myometrium were greater than those in nonpregnant myometrium. CPI-17 is a substrate for PKC, and the phosphorylated CPI-17 is considered to inhibit myosin phosphatase. The levels of CPI-17 mRNA and protein expression were also greater in the pregnant myometrium. These results suggest that the PKC-mediated contractile mechanism is augmented in human myometrium after gestation, and that this augmentation may be attributable to the increased activity of the , PKC isoform and CPI-17. British Journal of Pharmacology (2003) 140, 1303,1312. doi:10.1038/sj.bjp.0705552 [source]


    Rhabdomyosarcoma: Value of myogenin expression analysis and molecular testing in diagnosing the alveolar subtype

    CANCER, Issue 12 2004
    An analysis of 109 paraffin-embedded specimens
    Abstract BACKGROUND Identification of the alveolar subtype of rhabdomyosarcoma (ARMS) is important, because the poor prognosis associated with this subtype necessitates a modified therapeutic regimen. At present, ARMS diagnoses are made on the basis of histologic findings and the extent of myogenin immunopositivity. Nonetheless, the absence of an alveolar pattern in the solid variant, the low degree of differentiation in certain embryonal rhabdomyosarcomas (ERMS), and the increasing use of microbiopsy samples make the diagnosis of ARMS somewhat difficult. Two specific translocations have been found in ARMS, and fusion transcripts can be detected by reverse transcriptase,polymerase chain reaction (RT-PCR) analysis of paraffin-embedded tissue (PET). METHODS To assess the value of myogenin staining and molecular testing in the diagnosis of rhabdomyosarcoma, the authors examined 109 rhabdomyosarcoma samples (45 ARMS samples and 64 ERMS samples). Real-time RT-PCR analysis of PET was performed in all 109 rhabdomyosarcomas, and RT-PCR analysis of frozen material was performed in 24 cases. RESULTS PAX fusion transcripts were present in 44 cases (39 ARMS and 5 ERMS) and absent in 52 cases (2 ARMS and 50 ERMS). In 13 cases (4 ARMS and 9 ERMS), the results were not interpretable. Results were concordant between paired frozen and fixed tumor samples. All 35 interpretable ERMS samples that contained < 50% myogenin-positive cells failed to yield detectable PAX fusion transcripts. Of the 61 interpretable tumor samples (41 ARMS and 20 ERMS) that contained > 50% myogenin-positive cells, 44 (39 ARMS and 5 ERMS) yielded detectable PAX fusion transcripts. CONCLUSIONS The current study demonstrates that molecular detection of PAX fusion transcripts via real-time RT-PCR analysis of PET is a sensitive and specific method for the diagnosis of ARMS and that immunohistochemical analysis of myogenin expression can be used to select cases for such molecular testing. Although RT-PCR analysis appears not to possess diagnostic value in tumors with < 50% tumor cell immunopositivity, it is strongly recommended for the diagnosis of tumors containing > 50% myogenin-positive cells. Cancer 2004. © 2004 American Cancer Society. [source]