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J C Reed

Publications and source records attributed to J C Reed.

At least 487 records · Page 27Linked to original sources
PubMed1991

Transformed 3T3 cells have reduced levels and altered subcellular distribution of the major PKC substrate protein MARCKS.

The MARCKS (myristylated alanine-rich C-kinase substrate) protein is an abundant calmodulin-binding protein that is a major and specific endogenous substrate of protein kinase C (PKC). Stimulation of cells with phorbol esters or other activators of PKC has been shown previously to result in rapid phosphorylation of MARCKS proteins and redistribution of these myristylated C-kinase substrates from membrane to cytosol. Here we show that NIH3T3 murine fibroblasts transformed by p21-HA-C-RAS or pp60-V-SRC oncoproteins have markedly reduced levels of p68-MARCKS and that most of the remaining MARCKS protein is found in the cytosol. 3T3 cells containing a nontransforming oncoprotein p26-BCL2, in contrast, exhibited normal levels and distribution of p68-MARCKS. When taken together with recent evidence that MARCKS proteins are involved in regulating organization of the membrane cytoskeleton, our findings suggest that oncoprotein-mediated alterations in MARCKS protein levels and subcellular distribution may contribute to the development or maintenance of the transformed phenotype.

3T3 Cells↗
PubMed1991

Pleural infections: a clinical-radiologic review.

Pleural space infection is a common disorder that may result from a wide variety of causes and is associated with a wide range of etiologic agents. The authors reviewed retrospectively records of 102 patients with discharge diagnoses of empyema and/or bronchopleural fistula. Chest radiographs and computed tomography closest to the time of initial diagnosis were evaluated separately. In 78 cases of empyema, the etiologies included primary pulmonary infections (49%), postsurgical (23%), traumatic (11.5%), intraabdominal pathology (5%), and unknown (11.5%). In 24 cases of bronchopleural fistulas, the etiologies were previous surgical procedures (37.5%), pulmonary infections (37.5%), traumatic (4%), and unknown (21%).

Adolescent↗
PubMed1991

Image-guided catheter drainage of the infected pleural space.

Thoracic empyema occurs at all ages and has reported mortality rates of 10% to 75%. Most authors agree that complete drainage of complicated effusions or organized empyemas and reexpansion of atelectatic lung are important in obtaining a satisfactory clinical outcome. For initial tube drainage, a 26-F to 36-F chest tube traditionally has been inserted at the bedside. The results of this method of empyema evacuation have varied widely, with an overall cure rate reported to be 47%. Image-guided placement of smaller 8-F to 14-F catheters has been offered as an alternative therapy with an overall reported cure rate of 81% in 104 patients.

Catheterization↗
PubMed1991

Absence of t(14;18) major and minor breakpoints and of Bcl-2 protein overproduction in Reed-Sternberg cells of Hodgkin's disease.

The t(14;18) translocation, found in most human follicular non-Hodgkin's lymphomas (NHLs), juxtaposes the Bcl-2 oncogene at 18q21 with the immunoglobulin heavy chain locus at 14q32. As a result, the Bcl-2 protein is markedly overproduced. Most of the breakpoints on chromosome 18 cluster at one of two sites, the major breakpoint region (mbr) and the minor cluster region (mcr). Recently, others used the polymerase chain reaction (PCR) to detect the t(14;18) mbr in 32% of specimens diagnosed as Hodgkin's disease (HD). In an attempt to confirm and extend those observations the authors used PCR to assay for both the mbr and mcr in HD specimens diagnosed at their institution and examined the specimens for Bcl-2 overproduction. The authors subjected the DNAs from 28 well-characterized HD tumors of 26 patients to PCR analyses using primers specific for the t(14;18) mbr and mcr breakpoints. Based on various PCR controls, the authors ascertained that 26 of the 28 specimens contained amplifiable template DNA. Southern blotting of the amplification products showed that none of the 26 HD DNAs had detectable t(14;18) mbr or mcr breakpoints. By admixing small amounts of t(14;18)-bearing NHL DNA with HD DNA samples, the authors directly demonstrated that the sensitivity of the PCR assays was adequate for the molecular detection of t(14;18)-bearing cells at a frequency comparable to that of Reed-Sternberg cells and their variants in HD. Immunohistochemical studies employing a highly specific anti-Bcl-2 antiserum under conditions optimized to detect t(14;18)-mediated overexpression of the Bcl-2 gene showed that the Reed-Sternberg cells and variants in all 19 HD tumors examined were negative for Bcl-2 immunostaining. In conclusion, the PCR and immunohistochemical data provided evidence that the t(14;18) translocation was not involved in the pathogenesis of the HD cases.

Chromosomes, Human, Pair 18↗
PubMed1991

Differential regulation of the p72-74 RAF-1 kinase in 3T3 fibroblasts expressing ras or src oncogenes.

The c-raf-1 protooncogene encodes a p72-74 serine/threonine-specific kinase that has been implicated in growth factor-mediated signal transduction and malignant transformation. Here, we compared the effects of Ha-c-ras and v-src oncogenes on the regulation of p72-74 RAF-1 kinase in NIH3T3 cells. In both serum-starved and platelet-derived growth factor-treated v-src-transformed cells, the RAF-1 kinase was constitutively activated, displaying characteristic retarded mobility in electrophoretic gels and elevated activity in in vitro kinase assays. In contrast, the RAF-1 protein from quiescent ras-transformed cells did not exhibit constitutively shifted gel mobility or elevated kinase activity but did respond normally with regard to platelet-derived growth factor- and phorbol myristate acetate-induced changes in p72-74 RAF-1 phosphorylation and kinase activity. 3T3 cells transformed by ras, however, contained elevated levels of p72-74 RAF-1 protein (as determined by immunoblotting), suggesting an indirect influence on this kinase. Quantitative differences in the levels and subcellular distribution of immunodetectable protein kinase C enzymes did not account for the differences between src- and ras-transformed 3T3 cells with regard to regulation of the RAF kinase. These findings in serum-deprived 3T3 cells demonstrate that expression of a ras oncogene can be insufficient for full activation of the p72-74 RAF-1 kinase, implying necessity for an additional growth factor-mediated stimulus.

Animals↗
PubMed1991

Phorbol ester-mediated inhibition of growth and regulation of proto-oncogene expression in the human T cell leukemia line JURKAT.

The expression and function of several proto-oncogenes were examined in a human acute T cell leukemia line, JURKAT, during phorbol ester-induced terminal differentiation. Treating JURKAT cells with the phorbol ester tetradecanoyl phorbol acetate (TPA) inhibited their proliferation and induced expression of the gene for the interleukin 2 receptor alpha chain (IL2R-alpha), consistent with previous reports. In unstimulated proliferating JURKAT cells, high levels of C-MYC, N-RAS, and BCL2 mRNAs were found that diminished rapidly following TPA-induced cessation of growth. In contrast, accumulation of mRNAs for the C-FOS, C-JUN, and EGR-1 genes increased markedly in TPA-treated cells and preceded the induction of IL2R-alpha mRNA. Expression of C-MYB, C-RAF-1, C-LCK, C-FYN, and C-FGR proto-oncogenes was relatively unchanged. To explore directly the function of two of these protooncogenes in regulating the growth of JURKAT T cells, we stably transferred C-MYC and BCL2 expression plasmids into these cells. Despite sustained expression of C-MYC, BCL2, or the combination of these protooncogenes, TPA continued to inhibit JURKAT cell growth and to induce IL2R expression. Thus, although C-MYC and BCL2 proto-oncogene expression correlated with proliferation in TPA-treated JURKAT cells, continuous over-expression of even the combination of these oncogenes was insufficient for abrogating the effects of TPA in these leukemic T cells. Because human lymphoid malignancies frequently contain chromosomal translocations that deregulate the expression of C-MYC and BCL2, our findings could have relevance for attempts to induce terminal differentiation of leukemic cells by in vitro exposure of patients' bone marrow cells to phorbol esters.

Blotting, Northern↗
PubMed1990

Role of bcl-2 in growth factor triggered signal transduction.

The role of bcl-2 in the signal transduction pathway was assessed by studying the inositol phospholipid metabolism in fibroblasts transfected by this oncogene. The rate of accumulation of water soluble inositol phosphates in response to several growth factors was much higher in bcl-2 transfected NIH3T3 clones than in untransfected control. Moreover, bcl-2 transfected clones express elevated levels of phosphatidic acid, a phospholipid produced during receptor stimulated breakdown of phosphoinositides. Our findings suggest that the expression of bcl-2 in NIH3T3 fibroblasts leads to the coupling of growth factor receptors to stimulate inositol phosphate production, henceforth establishing its role in the growth factor receptor mediated signal transduction pathway.

Animals↗
PubMed1990

Antisense-mediated inhibition of BCL2 protooncogene expression and leukemic cell growth and survival: comparisons of phosphodiester and phosphorothioate oligodeoxynucleotides.

Antisense oligodeoxynucleotides specific for sequences in mRNAs from the B-cell lymphoma/leukemia-2 (BCL2) gene were used to inhibit the growth in culture of a human leukemia cell line, 697. Normal phosphodiester (PO) and nuclease-resistant phosphorothioate (PS) oligodeoxynucleotides were compared with regard to specificity, potency, and kinetics. Both PO and PS antisense BCL2 oligodeoxynucleotides were specific inhibitors of cellular proliferation, since sense versions of these synthetic DNAs were inactive at similar concentrations. Specificity was further confirmed by quantitative immunofluorescence studies, showing that PO and PS antisense BCL2 oligodeoxynucleotides (when used at appropriate concentrations) reduced levels of BCL2 protein without influencing expression of HLA-DR and other control antigens. The onset of inhibition by PO oligodeoxynucleotides was faster, with reductions in cell numbers occurring within 1 day of addition to cultures, in contrast to phosphorothioates, which were ineffective until 3-4 days. Phosphorothioates were more potent that phosphodiesters, however, with half-maximal inhibition of leukemic cell growth occurring at concentrations 5-10 times lower. As expected from previous studies demonstrating the importance of BCL2 for regulating lymphoid cell survival, BCL2 antisense oligodeoxynucleotides also led to 697 leukemic cell death through sequence-specific mechanisms, with reductions in cellular viability generally lagging the inhibitory effects on cellular growth by about 2 days. Taken together, these data indicate that PO and PS oligodeoxynucleotides targeted against the human BCL2 protooncogene can be sequence-specific inhibitors of leukemic cell growth and survival.

Cell Division↗
PubMed1990

BCL2-mediated tumorigenicity of a human T-lymphoid cell line: synergy with MYC and inhibition by BCL2 antisense.

A gene-transfer approach was used to explore the function of the BCL2 (B-cell lymphoma/leukemia 2) gene in a human T-cell line, Jurkat. Though stable introduction of a BCL2 expression plasmid into Jurkat T cells was by itself insufficient, the combined transfer of BCL2 and MYC genes markedly enhanced the tumorigenicity of these cells in athymic mice. Moreover, a BCL2 antisense expression plasmid ablated tumor formation by Jurkat cells, providing further evidence that this oncogene contributes to the regulation of the in vivo growth of these human T lymphocytes. In addition to their influence on tumor formation, BCL2 sense and antisense expression plasmids increased and decreased, respectively, the in vitro survival of Jurkat T cells in serum-free medium. These observations extend to T cells the finding of synergy of BCL2 with MYC previously reported for B cells and provide evidence that BCL2 can regulate the growth of human T cells.

Animals↗
PubMed1990

Complementation by BCL2 and C-HA-RAS oncogenes in malignant transformation of rat embryo fibroblasts.

The BCL2 (B cell lymphoma/leukemia-2) and C-HA-RAS oncogenes encode membrane-associated proteins of 26 and 21 kilodaltons, respectively. Although RAS proteins have long been known for their ability to bind and hydrolyze GTP, recent investigations suggest that BCL2 encodes a novel GTP-binding protein (S. Haldar, C. Beatty, Y. Tsujimoto, and C. M. Croce, Nature [London] 342:195-198, 1989). Cotransfection of BCL2 and HA-RAS oncogenes resulted in morphological transformation of early-passage rodent fibroblasts, rendering these cells tumorigenic in animals and enabling them to grow in semisolid medium. In contrast, cotransfection of BCL2 with oncogenes that encode nuclear proteins (E1A and C-MYC) did not produce malignant transformation, whereas HA-RAS did complement with these genes. These findings suggest that proteins encoded by oncogenes such as BCL2 and HA-RAS, although having similar subcellular locations and perhaps similar biochemical properties, can regulate distinct complementary pathways involved in cellular transformation.

Animals↗
PubMed1990

Radiographic detection of esophageal malpositioning of endotracheal tubes.

Insertion of an endotracheal tube into the esophagus is an infrequent but life-threatening complication of endotracheal intubation. This complication is difficult to detect on standard, anteroposterior, portable chest radiographs because the incorrectly placed endotracheal tube is usually projected over the tracheal air column. To evaluate the use of chest radiographs to detect the malposition, we performed a two-part study. First, we analyzed the findings on chest radiographs in six patients in whom an endotracheal tube had been inserted in the esophagus, and then we analyzed 328 portable chest radiographs of patients with both endotracheal and nasogastric tubes to determine the best radiographic position for identifying the exact location of an endotracheal tube. The findings in the six patients included projection of the tube lateral to the trachea (five patients), gastric distension (four patients), esophageal air (two patients), and deviation of the trachea by the balloon cuff (one patient). The study of the portable chest radiographs showed that the endotracheal tube position could be identified correctly in 81 (92%) of 88 of the films made with the patient in a 25 degrees right posterior oblique position. The trachea and esophagus were superimposed in 25 (96%) of 26 of the radiographs made with the head turned to the left and with the patient in a 25 degrees left posterior oblique projection. Our results show that by positioning patients for chest radiographs in a 25 degrees right posterior oblique position, the location of endotracheal tubes can be identified accurately.

Esophagus↗
PubMed1989

Regulation of bcl-2 gene expression in lymphoid cell lines containing normal #18 or t(14;18) chromosomes.

The bcl-2 (B cell lymphoma/leukemia-2) gene at band 18q21 is involved in t(14;18) chromosomal translocations in most follicular lymphomas and occasional other human B cell malignancies, where it becomes juxtaposed to the transcriptionally active immunoglobulin (Ig) locus at 14q32. Regulation of bcl-2 gene expression was investigated in neoplastic lymphoid cell lines containing normal #18 chromosomes or a t(14;18) translocation with regard to steady-state mRNA levels, RNA stability, transcription rates, and DNA methylation. High steady-state levels of bcl-2 mRNA, and proportionally high rates of bcl-2 transcription (measured in isolated nuclei), were found in B cell lines containing t(14;18) translocations. The half-life of bcl-2 mRNA (approximately 2-3 hr) was similar in all cell lines examined, including a t(14;18)-containing follicular lymphoma cell line, which has a translocated and rearranged bcl-2 gene that produces bcl-2/Ig fusion transcripts. However, in the presence of cycloheximide (inhibitor of protein synthesis), the half-life of some of the bcl-2/Ig mRNAs produced by these cells was prolonged, indicating that in some circumstances mRNA stability may contribute to deregulated bcl-2 expression. Despite stabilizing some bcl-2 mRNAs, the overall effect of treating cell lines with cycloheximide was a reduction in the levels of accumulated bcl-2 mRNAs through inhibition of bcl-2 gene transcription. These latter data provide indirect evidence that short-lived transacting factor(s) regulate transcription of the human bcl-2 gene in lymphoid cells with or without a t(14;18) translocation. No clear correlation was discovered between bcl-2 gene methylation and transcription.

Blotting, Northern↗
PubMed1989

Deregulated BCL2 expression enhances growth of a human B cell line.

The BCL2 (B cell lymphoma/leukemia -2) and C-MYC oncogenes become activated by chromosomal translocations involving the immunoglobulin heavy chain locus in human follicular lymphomas and Burkitt lymphomas, respectively. Though much is known about the biological actions of C-MYC, little information is available concerning the functions of BCL2, particularly in human B cells. Using a gene transfer approach we contrasted the effects of deregulated BCL2 and C-MYC expression in a human EBV-immortalized B cell line GM607B. Both BCL2 and C-MYC enhanced the ability of GM607B cells to grow in reduced serum and in limiting dilution cultures. These findings provide direct evidence that BCL2 can alter the growth characteristics of human B lymphocytes, thus strengthening arguments for its role in the pathogenesis of human lymphomas.

B-Lymphocytes↗
PubMed1988

Oncogenic potential of bcl-2 demonstrated by gene transfer.

Follicular lymphoma is the most common human B-cell malignancy in the United States and Western Europe. Most of the tumours contain t(14;18) chromosome translocations involving the human bcl-2 gene. Translocation of bcl-2 sequences from chromosome 18 into the transcriptionally active immunoglobulin locus at chromosome band 14q32 in B cells deregulates bcl-2 gene expression, resulting in the accumulation of high levels of bcl-2 messenger. Human bcl-2 transcripts generate two proteins, p26 bcl-2-alpha and p22 bcl-2-beta, by virtue of alternative splice-site selection. Both proteins have in common their first 196 NH2-terminal amino acids but share little similarity with other sequences in a data bank. Although the biological and biochemical functions of bcl-2 are unknown, recent subcellular localization studies indicate that p26 bcl-2-alpha associates with cellular membranes, consistent with a stretch of hydrophobic amino acids in its carboxy terminus. The bcl-2 gene may represent a novel oncogene having no known retroviral counterpart. Here we demonstrate the oncogenic potential of bcl-2 through a gene transfer approach.

Animals↗
PubMed1988

Induction and regulation of CD2 mRNA in human lymphocytes.

Herein we studied the accumulation and decay of CD2 mRNA in human PBMC stimulated with PHA. The data show that CD2-specific messages are present in low quantities in resting PBMC and are rapidly increased by five- to sevenfold within 24 h of addition of optimal amounts of PHA. Similar induction of CD2 mRNA was seen after stimulation of PBMC with anti-CD3 mAb and PMA. Peak levels of CD2 message were maintained until 72 h post-stimulation and declined gradually thereafter. Despite stimulation with Staphylococcus aureus and PMA, purified B cells failed to demonstrate any CD2 mRNA. Unlike transferrin or IL-2R mRNA, Il-2 had no effect on the accumulation of CD2 messages in resting or PHA-stimulated PBMC. The time course of CD2 mRNA accumulation preceded lymphocyte proliferation and the appearance of additional cell surface CD2 Ag. The decay of CD2 mRNA was very rapid, with a t 1/2 of approximately 45 min. The protein synthesis inhibitor, cycloheximide, increased its half-time by fourfold to 3.5 h. The data imply the existence of a labile factor, dependent on protein synthesis that is important in the regulation of CD2 mRNA. Compared to other PHA-inducible lymphocyte genes, the kinetics of CD2 transcript accumulation are most reminiscent of the oncogenes N-ras and c-abl.

CD2 Antigens↗
PubMed1988

Regulation of gene expression in lectin-stimulated or lymphokine-stimulated T lymphocytes. Effects of cyclosporine.

The effects of cyclosporine were examined on gene expression induced in T lymphocytes by mitogenic lectins and interleukin 2 (IL-2). Used at concentrations that inhibited proliferation of human peripheral blood lymphocytes by approximately 90%, CsA suppressed, to different extents, the phytohemagglutinin-stimulated expression of various genes, with levels of mRNAs for IL-2 being inhibited by approximately 100%, c-myc and N-ras by approximately 80%, and c-fos and IL-2 receptors by approximately 50%. Comparisons of the actions of CsA on gene expression in a cloned murine T cell (L2), stimulated with concanavalin A or IL-2, demonstrated that CsA specifically blocked the accumulation of mRNAs for the c-myc and p53 protooncogenes when induced by Con A, but not when induced by IL-2. Taken together, these findings indicate that several pathways can control the expression of a particular gene, and suggest that CsA interferes with only some of these regulatory pathways of gene expression in T lymphocytes.

Cells, Cultured↗
PubMed1988

Interleukin-1-beta gene expression in human monocytes and alveolar macrophages from normal subjects and patients with sarcoidosis.

To assess the ability of human alveolar macrophages to produce interleukin-1-beta (IL1-beta), we examined IL1-beta mRNA accumulation in autologous monocytes and alveolar macrophages from normal volunteers. Escherichia coli lipopolysaccharide stimulation of monocytes induced rapid IL1-beta mRNA accumulation, reaching a maximum at 2 to 4 h and declining thereafter. Alveolar macrophages, however, accumulated much less mRNA than did monocytes. This difference could not be explained by differences in kinetics of IL1-beta gene expression between the 2 cell types, isolation techniques, or alveolar macrophage lidocaine exposure. This suggests that differences in transcription of the IL1-beta gene exist between these 2 cell types. Aging is a possible factor important in some functional differences between these 2 cell types. To determine if this difference in the capacity to express the IL1-beta gene might be a function of cell maturity, monocytes were aged in vitro for 7 days. After this culture period, monocytes had a marked decrease in the ability to accumulate IL1-beta mRNA, suggesting that cell aging may be one mechanism involved in producing these transcriptional differences. Because IL1-beta has also been implicated in the inflammatory and fibrotic responses in pulmonary sarcoidosis, 4 patients with newly diagnosed sarcoidosis underwent bronchoalveolar lavage, and IL1-beta mRNA accumulation was compared in their alveolar macrophages and blood monocytes. Comparing normal alveolar macrophages to those from patients with sarcoidosis showed no differences in the kinetics of IL1-beta mRNA expression or in the LPS-induced levels of IL1-beta mRNA accumulation. In addition, augmented levels of IL1-beta transcript were not noted in unstimulated sarcoid alveolar macrophages.(ABSTRACT TRUNCATED AT 250 WORDS)

Blotting, Northern↗