Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.7.49 (reverse transcriptase)
 31,746 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Mouse transforming growth factor alpha (TGF alpha) gene expression was determined by reverse transcriptase-polymerase chain reaction (RT-PCR) method in pregnant mammary glands and mammary tumors in C3H/He mice. Both normal pregnant and tumorous mammary tissues expressed mRNA for mouse TGF alpha. When primers from rat TGF alpha cDNA sequence as well as those in the previous report [12] were used, the PCR amplified products were the same sizes in both normal pregnant mammary gland and tumor. However, there were obviously different PCR products between pregnant mammary gland and tumor in case of using primers according to the mouse TGF alpha cDNA sequence. In tumors, various sizes of PCR products were detected in addition of a predicted size. This is unlikely the experimental artifact, but the polymorphic TGF alpha gene expression is induced in mammary tumors.
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PMID:Different gene expression of mouse transforming growth factor alpha between pregnant mammary glands and mammary tumors in C3H/He mice. 776 2

The purpose of the present experiments was to examine dose-response relationships for induction of hepatic mRNA following a single administration of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) to rats. The induction of cytochrome P450-1A1 (CYP1A1) mRNA is compared to other "dioxin-responsive" genes including UDP-glucuronosyltransferase I, plasminogen activator inhibitor 2, and transforming growth factor alpha using a sensitive reverse transcriptase-polymerase chain reaction-based method. Sample-to-sample variability in amplification is a concern in using polymerase chain reaction to quantitate biological responses. However, in the present study recombinant RNA templates were synthesized to use as internal standards in both the reverse transcription and the polymerase chain reaction steps. The induction of CYP1A1 mRNA was extremely sensitive to TCDD treatment with increases observed at doses as low as 1 ng/kg body weight. The induction of CYP1A1 mRNA correlated highly (R2 > 0.90) with an increase in ethoxyresorufin-o-deethylase activity, a CYP1A1-associated enzyme activity. However, induction of CYP1A1 mRNA levels was detected at lower TCDD doses than was ethoxyresorufin-o-deethylase activity, reflecting the greater sensitivity of the reverse transcription-polymerase chain reaction approach to detect transcriptional activation of the CYP1A1 gene. UDP-glucuronosyltransferase I mRNA was increased over control (5-fold) but required 1000-times higher TCDD doses (1 microgram/kg) to result in a significant increase than did CYP1A1. Plasminogen activator inhibitor 2 and transforming growth factor alpha mRNA, both previously shown to be induced by TCDD in human keratinocytes, were not increased in rat liver. Hence, these studies reaffirm that TCDD acts through classical receptor mechanisms with gene-to-gene differences in responsiveness. The reverse transcription-polymerase chain reaction method developed to measure mRNA for dioxin-responsive genes in rat liver will allow for measuring multigene and tissue responses to TCDD and other xenobiotics with high sensitivity, reproducibility, and adaptability and should increase our understanding of various dose-response relationships.
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PMID:Dioxin-responsive genes: examination of dose-response relationships using quantitative reverse transcriptase-polymerase chain reaction. 826 64

The expression of mRNA for the epidermal growth factor (EGF) receptor, EGF and transforming growth factor alpha (TGF-alpha) was determined in 76 malignant, six borderline and 15 benign primary ovarian tumours using the reverse transcriptase-polymerase chain reaction and related to clinical and pathological parameters. Of the malignant tumours, 70% (53/76) expressed EGF receptor mRNA, 31% (23/75) expressed EGF mRNA and 35% (26/75) expressed TGF-alpha mRNA. For the borderline tumours, four of six (67%) expressed EGF receptor mRNA, 1/6 (17%) expressed TGF-alpha mRNA and none expressed EGF mRNA. Finally, 33% (5/15) of the benign tumours expressed EGF receptor mRNA, whereas 40% (6/15) expressed EGF mRNA and 7% (1/15) expressed TGF-alpha mRNA. The presence of the EGF receptor in malignant tumours was associated with that of TGF-alpha (P = 0.0015) but not with EGF (P = 1.00), whereas there was no relationship between the presence of EGF and TGF-alpha (P = 1.00). EGF receptor mRNA expression was significantly and positively associated with serous histology (P = 0.006) but not with stage or grade. Neither EGF nor TGF-alpha showed any link with histological subtype or stage. The survival of patients with malignant tumours possessing EGF receptor mRNA was significantly reduced compared with that of patients whose tumours were negative (P = 0.030 for all malignant tumours; P = 0.007 for malignant epithelial tumours only). In contrast, neither the expression of TGF-alpha nor EGF was related to survival. These data suggest that the presence of EGF receptor mRNA is associated with poor prognosis in primary ovarian cancer.
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PMID:The prognostic value of epidermal growth factor receptor mRNA expression in primary ovarian cancer. 856 34

Hepatocyte growth factor (HGF) and transforming growth factor alpha (TGF-alpha) stimulate liver regeneration, whereas transforming growth factor beta 1 (TGF-beta 1) inhibits it in rats. However their significance in human liver diseases, especially in severe acute liver injury, remains unclear. We studied HGF, TGF-alpha, and TGF-beta 1 messenger RNA (mRNA) expression in the livers of patients with live diseases using a competitive reverse transcriptase polymerase chain reaction. As little as a twofold difference in mRNA expression could be detected from minute liver biopsy samples. We then examined cell proliferation using proliferating cell nuclear antigen (PCNA) staining. HGF mRNA levels were significantly higher (approximately threefold) in acute hepatitis (AH) than in exacerbation of chronic liver disease (EX) (P < .05). TGF-alpha mRNA levels were significantly greater in AH (approximately twofold) than EX (P < .05), and the levels were significantly higher (approximately threefold) in chronic hepatitis (CH) than in EX (P < .05). The TGF-beta 1 mRNA levels in all the groups were not significantly different. In acute liver injury (AH and EX), there was a significant correlation between HGF mRNA expression and the PCNA labeling index (LI) in the liver (r = .87, P < .005). TGF-alpha mRNA expression also correlated with the PCNA LI (r = .92,P < .0001). There was no significant correlation between the serum HGF and the PCNA LI in the liver. In conclusion, HGF and TGF-alpha produced in the liver stimulate hepatocyte proliferation in response to acute liver injury in humans.
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PMID:Expression of hepatocyte growth factor, transforming growth factor alpha, and transforming growth factor beta 1 messenger RNA in various human liver diseases and correlation with hepatocyte proliferation. 869 Apr

Previous studies have indicated that growth factors such as epidermal growth factor, transforming growth factor alpha, and fibroblast growth factor 1 (FGF-1) have important regulatory functions in murine urothelial wound healing and tumorigenesis. Immunocytochemical analyses suggest that these factors are also involved in human urothelium. Yet, little is known about the functional effects of these growth factors on human urothelial cells. We established organoid-like primary cultures of normal human urothelium on porous membranes. Direct functional effects of growth factors were examined on confluent cultures reflecting intact urothelium. Immunocytochemistry was performed with a panel of specific antibodies against growth factors and their receptors on both cultures and the corresponding tissue sections. Lacking the appropriate antibodies, we performed reverse transcriptase PCR to detect FGF receptor mRNA in cultures and dissected tissue. The proliferation was stimulated by transforming growth factor alpha, FGF-1, and weakly by FGF-7, but not by FGF-2. TGF beta 1 inhibited proliferation. In contrast to mouse urothelium, none of the growth factors showed an effect on differentiation. The functional data correlate with the urothelial expression of epidermal growth factor receptors, TGF beta receptor types I and II, the (low) protein expression of FGF receptor 1, and the presence of FGF-7 receptor (FGF receptor 2 (IIIb)) mRNA. The organotypic nature of the cultures permits the study of growth factor interactions between urothelial cells. The data indicate that FGF-1, transforming growth factor alpha, and TGF beta 1 contribute differently to the maintenance of human urothelium.
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PMID:Functions of fibroblast and transforming growth factors in primary organoid-like cultures of normal human urothelium. 876 15

In the experiment of mouse transforming growth factor alpha (TGF alpha) gene expression in mammary tumors, various sizes of amplified products by reverse transcriptase-polymerase chain reaction (RT-PCR) using mouse TGF alpha primers were detected in addition to a predicted size in four strains of mice. During the further analysis of these RT-PCR products in mouse mammary tumors, the transcript of neurocan gene was detected in the mammary tumor from SHN mice by the cloning and nucleotide sequence analysis after RT-PCR reaction using mouse TGF alpha primers. The 5'-nucleotide sequence of sequential 246bp in the amplified cDNA of 527bp was completely identical to a middle part of mouse neurocan cDNA sequence, one of the chondroitin-sulfate proteoglycan expressed in the nervous tissue.
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PMID:The mRNA expression of neurocan, a brain-specific chondroitin sulfate proteoglycan, in neoplastic mammary glands in mice. 900 55

We previously reported the induction with N-methyl-N-nitrosourea (MNU) of mouse glandular stomach carcinomas showing a gastric phenotype but variation in histologic appearance, as with human gastric carcinomas. In the present study, we established two cell lines, designated MGT-40 and MGT-93, from MNU-induced mouse glandular stomach carcinomas. These cell lines are keratin-positive and grow as epithelial monolayers in culture, requiring transforming growth factor alpha, epidermal growth factor or insulin/transferrin for optimal growth in addition to 10% fetal bovine serum. Retention of the differentiated phenotype for gastric surface mucous cells has been confirmed by cathepsin E immunohistochemistry and reverse transcriptase-polymerase chain reaction for mouse spasmolytic polypeptide. Neither transplantability in nude mice nor colony formation on soft agar was observed, except in one subline. Chromosome analysis revealed aneuploidy with modal chromosome numbers ranging from 58 to 78 and no specific structural abnormalities. This is the first report of cell lines derived from mouse glandular stomach carcinomas. They should prove useful for studies of the mechanisms of regulation of growth and differentiation.
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PMID:Establishment and characterization of two cell lines from N-methyl-N-nitrosourea-induced mouse glandular stomach carcinomas. 968 55

We examined the expression of selected growth factors, growth factor receptors, elements of extracellular matrix and cell adhesion molecules in the germinal matrix layer (GML) utilizing immunohistochemistry and reverse transcriptase polymerase chain reaction. At autopsy brain samples from 10 neonatal infants were used. Epidermal growth factor receptor (EGFR) was significantly expressed in the matrix cells. While transforming growth factor alpha and heparin-binding epidermal growth factor-like growth factor were found in the matrix cells or vascular wall as ligands, epidermal growth factor was not expressed. EGFR and its ligands are thought to be important factors for the maintenance of the matrix cells and cell-to-cell interactions. Insulin like growth factor I, its receptor Ibeta and tenascin were found in the stroma of the GML and periventricular region. Vascular endothelial growth factor and receptor Flk-1, laminin A and B2, fibronectin, collagen type IV and integrins such as beta3, alpha5beta1 and alphaVbeta3 were found mainly in or around the vascular wall indicating their important roles for vascularization. Transforming growth factor beta2 and its receptor II were expressed in the matrix cells and/or vascular wall suggesting a role in proliferation and/or regression of the vasculature. CD44 and Thy-1 were also expressed in the matrix cells.
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PMID:Growth factors in infant germinal matrix: relationship to extracellular matrix and cell adhesion molecules. 973 49

We demonstrate the constitutive expression of interleukin 6 (IL-6), IL-8, granulocyte-macrophage colony-stimulating factor (GM-CSF), epidermal growth factor (EGF), transforming growth factor alpha (TGF-alpha) and epidermal growth factor receptor (EGFR) in normal kidney cells, and in the majority of renal oncocytomas, papillary and non-papillary renal cell carcinomas (RCCs) by reverse transcriptase polymerase chain reaction (RT-PCR) technique. No expression of IL-6 and TGF-alpha and variable expression of GM-CSF, IL-8, EGF and EGFR was seen in chromophobe RCCs. The lack of expression of IL-6 and TGF-alpha might be correlated with the growth pattern, poor vascularity and low malignancy of chromophobe RCCs.
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PMID:Lack of interleukin 6 (IL-6) and transforming growth factor alpha (TGF-alpha) expression in chromophobe renal cell carcinomas. 982 Jan 73

A change in the balance between proliferation and apoptosis in the course of hepatocellular carcinoma (HCC) development and progression has been suspected. We wanted to identify related genes whose mRNA levels could provide markers of severity and prognosis after resection. The extent of cell apoptosis, proliferation, and differentiation was measured with a terminal deoxynucleotidyl transferase-mediated deoxyuridine 5-triphosphate-biotin nick-end labeling assay, and the Ki-67 index was determined in paired tumor and cirrhotic tissue samples from patients who had undergone HCC resection after diagnosis of hepatitis C-related or alcoholism-related cirrhosis. These patients included two groups with highly versus poorly differentiated tumor cells, and the latter was split into two subgroups of those with versus without early recurrence. The mRNA levels for various apoptosis-related or proliferation-related genes and those for the growth factor/receptor systems were measured by quantitative reverse transcriptase-polymerase chain reaction in paired tumor and cirrhotic liver samples from every patient, and some of the corresponding proteins were detected by immunohistochemistry. In all instances, protein expression was highly heterogeneous within groups and similar between groups. In contrast, some differences in mRNA level between tumor and cirrhotic tissues were quite informative. Low levels of hepatocyte growth factor and transforming growth factor alpha mRNAs were found concomitantly in highly differentiated tumors, whereas overexpression of mRNAs for the cognate receptors c-met and epidermal growth factor receptor were found in poorly differentiated tumors and primarily in patients with early tumor recurrence. These results argue for growth factor-dependent HCC development and provide novel and combined prognosis markers after HCC surgery.
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PMID:Hepatocyte growth factor, transforming growth factor alpha, and their receptors as combined markers of prognosis in hepatocellular carcinoma. 1261 35


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