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Bendell JC, Percent IJ, Weaver RW, Chua CC, Xiong HQ, Cohn AL, Zakari A, Singh J, Kozloff M, Lietman C, Lane CM, Jones SF, Finney LH, Carmody S, Womack MS. A phase II study of nab-paclitaxel plus ramucirumab for the second-line treatment of patients with metastatic gastroesophageal cancer. J Clin Oncol 2020. [DOI: 10.1200/jco.2020.38.4_suppl.365] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
365 Background: Nab-paclitaxel (NP) is a protein-stabilized formulation of paclitaxel, US FDA approved for treatment of metastatic breast cancer, advanced/metastatic non-small cell lung cancer and metastatic adenocarcinoma of the pancreas. Ramucirumab (R) is an antibody targeting vascular epithelial growth factor receptor 2 (VEGFR-2) approved for treatment of gastric or gastroesophageal (GE) adenocarcinoma in combination with paclitaxel as 2nd line treatment. This phase II study evaluated the efficacy of NP and R for pts with metastatic GE cancer. Methods: Pts with metastatic GE adenocarcinoma were treated with 125 mg/m2 NP on days 1, 8, and 15, and 8 mg/kg R on days 1 and 15 of each 28-day cycle. Pts continued study treatment (tx) until intolerable toxicity, disease progression (PD), or withdrawal of consent. Restaging occurred every 2 cycles. The primary objective was progression-free survival (PFS); secondary objectives were response rate (RR), time to progression (TTP), overall survival (OS) and toxicity. Results: 65 pts were enrolled between 05/15 and 12/18: median age 63 yrs (35-86), 75% male, 71% ECOG 1. Primary tumor sites were stomach (37%), GE junction (35%), and esophagus (28%). 83% were stage IV at initial diagnosis. 29% were HER2+ at study entry. 57% had 1st line chemo, 40% chemo + targeted agent and 3% chemo + immunotherapy. Median tx duration was 13 weeks (.1-55) for NP and 12 weeks (.1-54) for R; at data cutoff 2 pts remained on tx.60% discontinued due to PD; 17% due to AE. 43% and 23% had AE-related dose reductions of NP and R, respectively; 8% and 6% were on day 15. 58% had dose interruptions of R due to AE; 42% on day 15. Median PFS was 3.8 months (CI 95% 3.4, 4.8); median TTP 4.5 months (CI 95% 3.5, 6.3); and median OS 8.8 months (CI 95% 6.1, 11.3). RR was 15% (CI 95% 6.6, 24.2); disease control rate was 68% (CI 95% 56.3, 79.1). Most common tx related AEs were neutropenia (55%), fatigue (40%), peripheral neuropathy (37%), anorexia and mucositis (26% each). Conclusions: There were no unexpected toxicity findings with NP and R in pts with GE cancers. Compared to historical controls, outcomes in this study were similar to those seen in the Western population of pts who received paclitaxel plus R. Clinical trial information: NCT02317991.
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Affiliation(s)
| | - Ivor John Percent
- Florida Cancer Specialists South/Sarah Cannon Research Institute, Port Charlotte, FL
| | | | | | - Henry Q. Xiong
- The Center for Cancer and Blood Disorders, Fort Worth, TX
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Fuchs CS, Shitara K, Di Bartolomeo M, Lonardi S, Al-Batran SE, Van Cutsem E, Ilson DH, Alsina M, Chau I, Lacy J, Ducreux M, Mendez GA, Alavez AM, Takahari D, Mansoor W, Enzinger PC, Gorbounova V, Wainberg ZA, Hegewisch-Becker S, Ferry D, Lin J, Carlesi R, Das M, Shah MA, Karaseva NA, Kowalyszyn RD, Hernandez CA, Csoszi T, De Vita F, Pfeiffer P, Sugimoto N, Kocsis J, Csilla A, Bodoky G, Garnica Jaliffe G, Protsenko S, Madi A, Wojcik E, Brenner B, Folprecht G, Sarosiek T, Peltola KJ, Bono P, Ayala H, Aprile G, Gerardo CG, Huitzil Melendez FD, Falcone A, Di Costanzo F, Tehfe M, Mineur L, García Alfonso P, Obermannova R, Senellart H, Petty R, Samuel L, Acs PI, Hussein MA, Nechaeva MN, Erdkamp F, Won E, Bendell JC, Gallego Plazas J, Lorenzen S, Melichar B, Escudero MA, Pezet D, Phelip JM, Kaen DL, Reeves JAJ, Longo Muñoz F, Madhusudan S, Barone C, Fein LE, Gomez Villanueva A, Hebbar M, Prausova J, Visa Turmo L, Vidal Barrull J, Yilmaz MKN, Beny A, Van Laarhoven H, DiCarlo BA, Esaki T, Fujitani K, Geboes K, Geva R, Kadowaki S, Leong S, Machida N, Raj MS, Ramirez Godinez FJ, Ruzsa A, Ford H, Lawler WE, Maisey NR, Petera J, Shacham-Shmueli E, Sinapi I, Yamaguchi K, Hara H, Beck JT, Błasińska-Morawiec M, Villalobos Valencia R, Alcindor T, Bajaj M, Berry S, Gomez CM, Dammrich D, Patel R, Taieb J, Ten Tije A, Burkes RL, Cabanillas F, Firdaus I, Chua CC, Hironaka S, Hofheinz RD, Lim HJ, Nordsmark M, Piko B, Verma U, Wadsley J, Yukisawa S, Gutiérrez Delgado F, Denlinger CS, Kallio R, Pikiel J, Wojcik-Tomaszewska J, Brezden-Masley C, Jang RWJ, Pribylova J, Sakai D, Bartoli MA, Cats A, Grootscholten M, Dichmann RA, Hool H, Shaib W, Tsuji A, Van den Eynde M, Velez-Cortez H, Asmis TR. Ramucirumab with cisplatin and fluoropyrimidine as first-line therapy in patients with metastatic gastric or junctional adenocarcinoma (RAINFALL): a double-blind, randomised, placebo-controlled, phase 3 trial. Lancet Oncol 2019; 20:420-435. [PMID: 30718072 DOI: 10.1016/s1470-2045(18)30791-5] [Citation(s) in RCA: 182] [Impact Index Per Article: 36.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 10/03/2018] [Accepted: 10/16/2018] [Indexed: 12/18/2022]
Abstract
BACKGROUND VEGF and VEGF receptor 2 (VEGFR-2)-mediated signalling and angiogenesis can contribute to the pathogenesis and progression of gastric cancer. We aimed to assess whether the addition of ramucirumab, a VEGFR-2 antagonist monoclonal antibody, to first-line chemotherapy improves outcomes in patients with metastatic gastric or gastro-oesophageal junction adenocarcinoma. METHODS For this double-blind, randomised, placebo-controlled, phase 3 trial done at 126 centres in 20 countries, we recruited patients aged 18 years or older with metastatic, HER2-negative gastric or gastro-oesophageal junction adenocarcinoma, an Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1, and adequate organ function. Eligible patients were randomly assigned (1:1) with an interactive web response system to receive cisplatin (80 mg/m2, on the first day) plus capecitabine (1000 mg/m2, twice daily for 14 days), every 21 days, and either ramucirumab (8 mg/kg) or placebo on days 1 and 8, every 21 days. 5-Fluorouracil (800 mg/m2 intravenous infusion on days 1-5) was permitted in patients unable to take capecitabine. The primary endpoint was investigator-assessed progression-free survival, analysed by intention to treat in the first 508 patients. We did a sensitivity analysis of the primary endpoint, including a central review of CT scans. Overall survival was a key secondary endpoint. This study is registered with ClinicalTrials.gov, number NCT02314117. FINDINGS Between Jan 28, 2015, and Sept 16, 2016, 645 patients were randomly assigned to receive ramucirumab plus fluoropyrimidine and cisplatin (n=326) or placebo plus fluoropyrimidine and cisplatin (n=319). Investigator-assessed progression-free survival was significantly longer in the ramucirumab group than the placebo group (hazard ratio [HR] 0·753, 95% CI 0·607-0·935, p=0·0106; median progression-free survival 5·7 months [5·5-6·5] vs 5·4 months [4·5-5·7]). A sensitivity analysis based on central independent review of the radiological images did not corroborate the investigator-assessed difference in progression-free survival (HR 0·961, 95% CI 0·768-1·203, p=0·74). There was no difference in overall survival between groups (0·962, 0·801-1·156, p=0·6757; median overall survival 11·2 months [9·9-11·9] in the ramucirumab group vs 10·7 months [9·5-11·9] in the placebo group). The most common grade 3-4 adverse events were neutropenia (85 [26%] of 323 patients in the ramucirumab group vs 85 [27%] of 315 in the placebo group), anaemia (39 [12%] vs 44 [14%]), and hypertension (32 [10%] vs 5 [2%]). The incidence of any-grade serious adverse events was 160 (50%) of 323 patients in the ramucirumab group and 149 (47%) of 315 patients in the placebo group. The most common serious adverse events were vomiting (14 [4%] in the ramucirumab group vs 21 [7%] in the placebo group) and diarrhoea (11 [3%] vs 19 [6%]). There were seven deaths in each group, either during study treatment or within 30 days of discontinuing study treatment, which were the result of treatment-related adverse events. In the ramucirumab group, these adverse events were acute kidney injury, cardiac arrest, gastric haemorrhage, peritonitis, pneumothorax, septic shock, and sudden death (n=1 of each). In the placebo group, these adverse events were cerebrovascular accident (n=1), multiple organ dysfunction syndrome (n=2), pulmonary embolism (n=2), sepsis (n=1), and small intestine perforation (n=1). INTERPRETATION Although the primary analysis for progression-free survival was statistically significant, this outcome was not confirmed in a sensitivity analysis of progression-free survival by central independent review, and did not improve overall survival. Therefore, the addition of ramucirumab to cisplatin plus fluoropyrimidine chemotherapy is not recommended as first-line treatment for this patient population. FUNDING Eli Lilly and Company.
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Affiliation(s)
- Charles S Fuchs
- Yale Cancer Center, Smilow Cancer Hospital, New Haven, CT, USA.
| | - Kohei Shitara
- National Cancer Center Hospital East, Kashiwa, Japan
| | | | | | - Salah-Eddin Al-Batran
- Institute of Clinical Cancer Research at Krankenhaus Nordwest, UCT-University Cancer Center, Frankfurt, Germany
| | - Eric Van Cutsem
- University Hospitals Gasthuisberg, Leuven and KULeuven, Belgium
| | - David H Ilson
- Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Maria Alsina
- Vall d'Hebron University Hospital and Institute of Oncology, Barcelona, Spain
| | - Ian Chau
- Royal Marsden Hospital, Sutton, Surrey, United Kingdom
| | - Jill Lacy
- Yale Cancer Center, Smilow Cancer Hospital, New Haven, CT, USA
| | - Michel Ducreux
- Gustave Roussy Cancer Centre, Grand Paris, Villejuif, France; Université Paris-Saclay, France
| | | | | | | | | | | | | | - Zev A Wainberg
- David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | | | - David Ferry
- Eli Lilly and Company, New York City, NY, USA
| | - Ji Lin
- Eli Lilly and Company, Indianapolis, IN, USA
| | | | - Mayukh Das
- Eli Lilly and Company, Indianapolis, IN, USA
| | - Manish A Shah
- Weill Cornell Medical College, NY, USA; New York Presbyterian Hospital, New York, NY, USA
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Abstract
To test whether the antiapoptotic protein Bcl-2 prevents apoptosis and injury of cardiomyocytes after ischemia-reperfusion (I/R), we generated a line of transgenic mice that carried a human Bcl-2 transgene under the control of a mouse alpha-myosin heavy chain promoter. High levels of human Bcl-2 transcripts and 26-kDa Bcl-2 protein were expressed in the hearts of transgenic mice. Functional recovery of the transgenic hearts significantly improved when they were perfused as Langendorff preparations. This protection was accompanied by a threefold decrease in lactate dehydrogenase (LDH) released from the transgenic hearts. The transgenic mice were subjected to 50 min of ligation of the left descending anterior coronary artery followed by reperfusion. The infarct sizes, expressed as a percentage of the area at risk, were significantly smaller in the transgenic mice than in the nontransgenic mice (36.6 +/- 5 vs 69.9 +/- 7.3%, respectively). In hearts subjected to 30 min of coronary artery occlusion followed by 3 h of reperfusion, Bcl-2 transgenic hearts had significantly fewer terminal deoxynucleodidyl-transferase nick-end labeling-positive or in situ oligo ligation-positive myocytes and a less prominent DNA fragmentation pattern. Our results demonstrate that overexpression of Bcl-2 renders the heart more resistant to apoptosis and I/R injury.
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Affiliation(s)
- Z Chen
- Cecile Cox Quillen Laboratory of Geriatrics, James H. Quillen School of Medicine, East Tennessee State University and James H. Quillen Veterans Affairs Medical Center, Johnson City, Tennessee 37614, USA
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4
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Chen Z, Oberley TD, Ho Y, Chua CC, Siu B, Hamdy RC, Epstein CJ, Chua BH. Overexpression of CuZnSOD in coronary vascular cells attenuates myocardial ischemia/reperfusion injury. Free Radic Biol Med 2000; 29:589-96. [PMID: 11033410 DOI: 10.1016/s0891-5849(00)00363-4] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Superoxide dismutase scavenges oxygen radicals, which have been implicated in ischemia/reperfusion (I/R) injury in the heart. Our experiments were designed to study the effect of a moderate increase of copper/zinc superoxide dismutase (CuZnSOD) on myocardial I/R injury in TgN(SOD1)3Cje transgenic mice. A species of 0.8 kb human CuZnSOD mRNA was expressed, and a 273% increase in CuZnSOD activity was detected in the hearts of transgenic mice with no changes in the activities of other antioxidant enzymes. Furthermore, immunoblot analysis revealed no changes in the levels of HSP-70 or HSP-25 levels. Immunocytochemical study indicated that there was increased labeling of CuZnSOD in the cytosolic fractions of both endothelial cells and smooth muscle cells, but not in the myocytes of the hearts from transgenic mice. When these hearts were perfused as Langendorff preparations for 45 min after 35 min of global ischemia, the functional recovery of the hearts, expressed as heart rate x LVDP, was 48 +/- 3% in the transgenic hearts as compared to 30 +/- 5% in the nontransgenic hearts (p <.05). The improved cardiac function was accompanied by a significant reduction in lactate dehydrogenase release from the transgenic hearts. Our results demonstrate that overexpression of CuZnSOD in coronary vascular cells renders the heart more resistant to I/R injury.
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MESH Headings
- Animals
- Antioxidants/metabolism
- Catalase/metabolism
- Coronary Vessels/enzymology
- Coronary Vessels/pathology
- Endothelium, Vascular/enzymology
- Endothelium, Vascular/pathology
- Glutathione Peroxidase/metabolism
- Glutathione Reductase/metabolism
- HSP27 Heat-Shock Proteins
- HSP70 Heat-Shock Proteins/metabolism
- Heat-Shock Proteins/metabolism
- Humans
- In Vitro Techniques
- L-Lactate Dehydrogenase/analysis
- Mice
- Mice, Inbred C3H
- Mice, Inbred C57BL
- Mice, Transgenic
- Molecular Chaperones
- Muscle, Smooth, Vascular/enzymology
- Muscle, Smooth, Vascular/pathology
- Myocardial Reperfusion Injury/pathology
- Myocardial Reperfusion Injury/prevention & control
- Myocardium/enzymology
- Myocardium/metabolism
- Neoplasm Proteins/metabolism
- RNA, Messenger/genetics
- Superoxide Dismutase/genetics
- Superoxide Dismutase/metabolism
- Transcription, Genetic
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Affiliation(s)
- Z Chen
- The Cecile Cox Quillen Laboratory of Geriatrics, James H. Quillen School of Medicine, East Tennessee State University, Johnson City, TN 37614, USA
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5
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Chua CC, Hamdy RC, Chua BH. Mechanism of transforming growth factor-beta1-induced expression of vascular endothelial growth factor in murine osteoblastic MC3T3-E1 cells. Biochim Biophys Acta 2000; 1497:69-76. [PMID: 10838160 DOI: 10.1016/s0167-4889(00)00040-9] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Transforming growth factor-beta1 (TGF-beta1), an abundant growth factor in bone matrix, has been shown to be involved in bone formation and fracture healing. The mechanism of action of the osteogenic effect of TGF-beta1 is not clearly understood. In this study, we found that the addition of TGF-beta1 to murine osteoblastic MC3T3-E1 cells induced vascular endothelial growth factor (VEGF) mRNA production. VEGF mRNA levels reached a plateau within 2 h after the addition of TGF-beta1. The induction was superinduced by cycloheximide and blocked by actinomycin D. Ro 31-8220, a protein kinase C inhibitor, abrogated the induction. In addition, curcumin, an inhibitor for transcription factor AP-1, also blocked the induction. Electrophoretic mobility shift assay revealed an enhanced binding of transcription factors AP-1 and NF-kappaB. Transient transfection experiment showed that VEGF promoter activity increased 3.6-fold upon TGF-beta1 stimulation. Immunoblot analysis showed that the amount of secreted VEGF was elevated in the medium 4 h after TGF-beta1 stimulation. Our results therefore suggest that at least part of the osteogenic activity of TGF-beta1 may be attributed to the production of VEGF.
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Affiliation(s)
- C C Chua
- Cecile Cox Quillen Laboratory of Geriatric Research, James Quillen School of Medicine, East Tennessee State University, Johnson City, TN 37614, USA.
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6
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Abstract
Hydrogen peroxide (H2O2) is a reactive oxygen species generated by several metabolic pathways in mammalian cells. Endothelial cells are extremely susceptible to oxidative stress. H2O2 has been reported to increase the permeability in these cells. Using rat heart endothelial cell culture as a model system, we examined the effect of H2O2 on the gene expression of vascular endothelial growth factor (VEGF), a potent mitogen of endothelial cells and a vascular permeability factor. By Northern blot analysis we found that VEGF mRNA responded to H2O2 in a dose-and time-dependent manner. The induction was superinduced by cycloheximide and blocked by actinomycin D. N-Acetylcysteine, a synthetic antioxidant, was able to suppress the induction. H7, a protein kinase C inhibitor, could also block the induction. Electrophoretic mobility shift assay revealed an enhanced binding of transcription factors, AP-1 and NF-kappaB. Immunoblot analysis showed that the amount of secreted VEGF was elevated in the medium 4 h after H2O2 stimulation. Our results demonstrate that VEGF gene expression is upregulated by H2O2 in these endothelial cells.
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Affiliation(s)
- C C Chua
- Cecile Cox Quillen Laboratory of Geriatric Research, James Quillen School of Medicine, East Tennessee State University, and Veterans Affairs Medical Center, Johnson City 37614, USA
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7
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Chen Z, Siu B, Ho YS, Vincent R, Chua CC, Hamdy RC, Chua BH. Overexpression of MnSOD protects against myocardial ischemia/reperfusion injury in transgenic mice. J Mol Cell Cardiol 1998; 30:2281-9. [PMID: 9925365 DOI: 10.1006/jmcc.1998.0789] [Citation(s) in RCA: 265] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Generation of free radicals upon reperfusion has been cited as one of the major causes of ischaemia/reperfusion injury. The following series of experiments was designed to study the effect of manganese superoxide dismutase (MnSOD) overexpression in transgenic mice on ischemia/reperfusion injury. A species of 1.4 kb human MnSOD mRNA was expressed, and a 325% increase in MnSOD activity was detected in the hearts of transgenic mice with no changes in the other antioxidant enzymes or heat shock proteins. Immunocytochemical study indicated an increased labeling of MnSOD mainly in the heart mitochondria of the transgenic mice. When these hearts were perfused as Langendorff preparations for 45 min after 35 min of global ischemia, the functional recovery of the hearts, expressed as heart rate x left ventricular developed pressure, was 52 +/- 4% in the transgenic hearts as compared to 31 +/- 4% in the non-transgenic hearts. This protection was accompanied by a significant decrease in lactate dehydrogenase release from the transgenic hearts. Overexpression of MnSOD limited the infarct size in vivo in a left coronary artery ligation model. Our results demonstrate that overexpression of MnSOD renders the heart more resistant to ischemia/reperfusion injury.
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Affiliation(s)
- Z Chen
- Cecile Cox Quillen Laboratory of Geriatrics, James H. Quillen School of Medicine, East Tennessee State University, James H. Quillen Veterans Affairs Medical Center, Johnson City 37614, USA
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8
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Abstract
Addition of lysophosphatidic acid (LPA) to rat aorta-derived endothelial cells significantly induced preproendothelin-1 (preproET-1) mRNA expression. PreproET-1 mRNA levels reached a plateau within 1 h after the addition of 0.5 microM LPA and declined after 2 h. The induction was superinduced by cycloheximide and was blocked by actinomycin D. Suramin, an LPA receptor antagonist, abolished the induction of preproET-1 mRNA by LPA. Protein kinase C inhibitors, H7 and bisindolylmaleimide, were able to block the induction. Transient transfection experiment revealed that the elevated preproET-1 mRNA was a result of the activation of ET-1 gene activity. Electrophoretic mobility shift assay revealed that LPA stimulated the binding of AP-1. The secreted level of ET-1 was elevated 2.3-fold after 12 h of stimulation with LPA. Our results suggest that the upregulation of preproET-1 by LPA may serve to augment and prolong the vasoconstriction action of LPA.
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Affiliation(s)
- C C Chua
- Division of Geriatric Medicine, James Quillen School of Medicine, East Tennessee State University, Box 70429, and Veterans Affairs Medical Center, Johnson City, TN 37614, USA
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9
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Abstract
Vascular endothelial growth factor (VEGF) is a potent mitogen for endothelial cells and a vascular permeability factor. In this study we found that the addition of angiotensin II (AII) to rat heart endothelial cells induced VEGF mRNA production. VEGF mRNA levels reached a plateau within 2 h after the addition of AII and decreased after 4 h. The induction was superinduced by cycloheximide and blocked by actinomycin D. Losartan, an AT1 receptor antagonist, abolished the induction of VEGF mRNA by AII, whereas PD 123319, an AT2 receptor antagonist, had no effect on VEGF mRNA induction. H7, a protein kinase C inhibitor, blocked the induction. RT-PCR experiments showed two mRNA species (VEGF 120 and VEGF 164) in these cells and both species were stimulated by AII. Transient transfection experiment showed that VEGF promoter activity was increased 2.2-fold upon AII stimulation. Electrophoretic mobility shift assay revealed an enhanced binding of transcription factors AP-1 and NF-kappa B. Immunoblot analysis showed that the amount of secreted VEGF was elevated in the medium 8 h after AII stimulation. Our results demonstrate for the first time that the upregulation of VEGF by AII may play a significant role in AII-induced hyperpermeability.
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Affiliation(s)
- C C Chua
- Cecile Cox Quillen Laboratory of Geriatric Research, James Quillen School of Medicine, East Tennessee State University, Johnson City, USA
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10
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Abstract
Thrombospondin-1 (TSP-1) is synthesized, secreted, and incorporated into the extracellular matrix by a variety of cells, including the endothelial cells. Addition of angiotensin II (AII) significantly induced TSP-1 mRNA in rat heart-derived endothelial cells. TSP-1 mRNA levels reached a plateau within 2 h after the addition of AII and decreased after 5 h. The induction was superinduced by cycloheximide and blocked by actinomycin D. Losartan, an AT1 receptor antagonist, could abolish the induction of TSP-1 mRNA by AII. Phorbol 12-myristate 13-acetate (TPA) was found to enhance TSP-1 mRNA level whereas a protein kinase C inhibitor, H7, was shown to block the induction. Immunoblot analysis revealed that TSP-1 was detectable in the medium 4 h after AII stimulation. Our results suggest that the upregulation of TSP-1 by AII represents an important mechanism leading to perivascular fibrosis in the heart.
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Affiliation(s)
- C C Chua
- Division of Geriatric Medicine, James Quillen School of Medicine, East Tennessee State University and Veterans Affairs Medical Center, Johnson City 37614, USA
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11
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Abstract
Thromboxane A2 (TXA2) and ET-1 have been known to play important roles in modulating vascular contraction and growth. The present study was undertaken to examine the effect of TXA2 on the induction of endothelin-1 (ET-1) mRNA and protein levels in smooth muscle cells derived from rat heart. U-46619, a stable TXA2 mimetic, superinduced preproET-1 mRNA in the presence of cycloheximide in these cells. This effect could be blocked by SQ-29548, a TXA2/prostaglandin H2 receptor antagonist and by actinomycin D, and RNA synthesis inhibitor. In addition, H7, a protein kinase C inhibitor, could abolish the induction. Transient transfection experiment revealed that the elevated ET-1 mRNA level after U-46619 treatment was a result of the activation of ET-1 gene activity. The elevated ET-1 message level was accompanied by increased ET-1 release into the cultured medium. These results show that the short-lived TXA2 can induce potent and long-lived ET-1. These findings support a potential role for ET-1 in the pathogenesis of coronary atherosclerosis and hypertension evoked by TXA2.
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MESH Headings
- 1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine
- 15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid
- Animals
- Bridged Bicyclo Compounds, Heterocyclic
- Cells, Cultured
- Endothelins/biosynthesis
- Endothelins/genetics
- Fatty Acids, Unsaturated
- Gene Expression/drug effects
- Hydrazines/pharmacology
- Isoquinolines/pharmacology
- Muscle, Smooth/metabolism
- Myocardium/cytology
- Piperazines/pharmacology
- Promoter Regions, Genetic
- Prostaglandin Endoperoxides, Synthetic/pharmacology
- Protein Kinase C/antagonists & inhibitors
- Protein Kinase C/physiology
- RNA, Messenger/genetics
- Rats
- Receptors, Thromboxane/antagonists & inhibitors
- Receptors, Thromboxane/physiology
- Thromboxane A2/analogs & derivatives
- Thromboxane A2/pharmacology
- Thromboxane A2/physiology
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Affiliation(s)
- C C Chua
- Division of Geriatric Medicine, James Quillen School of Medicine, East Tennessee State University, Johnson City, USA
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12
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Abstract
Angiotensin II (AII) was found to upregulate tissue inhibitor of metalloproteineses-1 (TIMP-1) gene expression in rat heart endothelial cells in a dose and time-dependent manner. The maximal stimulation of TIMP-1 mRNA was achieved by 2 h after the addition of AII. This effect was blocked by losartan, an AT1 receptor antagonist and by calphostin C, a protein kinase C inhibitor. Addition of cycloheximide superinduced and actinomycin D abolished the induction. These results suggest that AII stimulates TIMP-1 production by a protein kinase C dependent pathway which is dependent upon de novo RNA synthesis. Immunoprecipitation experiment showed an enhanced band of 28 kDa from the conditioned medium of AII-treated cultures. Immunoblot analysis revealed that TIMP-1 was detectable in the conditioned medium 4 h after AII stimulation. Since endothelial cells line the blood vessels and sense the rise in AII associated with hypertension, the TIMP-1 released by these cells may provide an initial trigger leading to cardiac fibrosis in angiotensin-renin dependent hypertension.
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Affiliation(s)
- C C Chua
- Division of Geriatric Medicine, East Tennessee State University, Johnson City 37614-0429, USA
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13
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Kirk TZ, Mark ME, Chua CC, Chua BH, Mayes MD. Myofibroblasts from scleroderma skin synthesize elevated levels of collagen and tissue inhibitor of metalloproteinase (TIMP-1) with two forms of TIMP-1. J Biol Chem 1995; 270:3423-8. [PMID: 7852429 DOI: 10.1074/jbc.270.7.3423] [Citation(s) in RCA: 109] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Cultured fibroblasts derived from skin biopsies from scleroderma patients and normal individuals were examined for the presence of smooth muscle alpha-actin, a marker for myofibroblasts. Six of eight scleroderma cell lines were found to be 50% or more positive for alpha-actin while three of four normal lines and one cell line derived from unaffected skin of a scleroderma patient were less than 10% positive. The cultured fibroblasts from affected scleroderma skin were largely myofibroblasts, a phenotype found in biopsies of scleroderma tissue, as well as other fibrotic lesions, wound healing, and tumor desmoplasia. The data support the hypothesis that a certain activated fibroblast phenotype predominates in scleroderma. The activated fibroblast is the myofibroblast. Both collagen and TIMP (tissue inhibitor of metalloproteinases) were elevated in the alpha-actin positive (myofibroblast enriched) cultures. In addition, the myofibroblast-enriched cultures displayed a more prominent TIMP doublet band pattern on SDS-polyacrylamide gel electrophoresis.
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Affiliation(s)
- T Z Kirk
- Department of Internal Medicine, Wayne State University School of Medicine, Detroit, Michigan 48201
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14
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Abstract
Angiotensin II (AII) was found to stimulate TGF-beta 1 gene expression in rat heart endothelial cells in a dose- and time-dependent manner. The maximal induction of TGF-beta 1 mRNA was achieved by 6 h after the addition of AII. This induction was blocked by losartan, an AT1 receptor antagonist and by calphostin C, a protein kinase C inhibitor. Addition of actinomycin D and cycloheximide abolished the induction. TGF-beta 1 promoter activities were stimulated 5-fold by AII. TGF-beta 1 secreted by the rat heart endothelial cells in response to AII was in a latent form and could be activated by mild heat treatment. These results suggest that AII stimulates TGF-beta 1 production by a protein kinase C-dependent pathway which is dependent upon de novo RNA synthesis and protein synthesis. Since endothelial cells line the blood vessels and sense the rise in AII associated with hypertension, the release of TGF-beta 1 by these cells may provide the initial trigger leading to cardiac fibrosis in angiotensin-renin-dependent hypertension.
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Affiliation(s)
- C C Chua
- Department of Pathology, Wayne State University, Detroit, MI 48201
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15
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Abstract
In a series of experiments carried out in cultured endothelial cells derived from rat hearts (RHE), angiotensin II (AII) is shown to stimulate preproendothelin-1 mRNA in a dose- and time-dependent manner. The induction of preproendothelin-1 mRNA is rapid, reaching a maximal level 1 h after the addition of AII (1 x 10(-8) M). The mRNA levels decline rapidly to basal levels in 4 h. The addition of Losartan (Dup 753; 1 x 10(-6) M), an AII receptor (type I) antagonist, blocks the AII effect. Calphostin C, a potent protein kinase C inhibitor, is able to abolish this effect of AII suggesting that the induction of preproendothelin-1 mRNA is mediated by a protein kinase C-dependent pathway. Since endothelial cells line the inner surface of the myocardium and blood vessels and sense the rise of AII associated with renovascular hypertension at the endothelial surface, these data suggest that endothelin which is produced by RHE cells in response to AII could be an important mediator which may play a role in modulating gene expression in AII-mediated cardiac hypertrophy.
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Affiliation(s)
- B H Chua
- Department of Pathology, School of Medicine, Wayne State University, Detroit, MI 48201
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16
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Abstract
The present work was carried out to assess the effect of endothelin on the relative synthesis of protein, RNA, and DNA in confluent rat aortic smooth muscle cells (SMC) derived from Wistar-Kyoto (WKY) rats maintained under serum-free medium in the presence or absence of insulin, transferrin, and selenium. Insulin stimulated protein synthesis by 42%. Endothelin (1 x 10(-7) M) rapidly induced protein synthesis by 22% (-insulin) and 30% (+insulin). Prior treatment of SMC for 4 h with endothelin resulted in 50% (-insulin) and 38% (+insulin) increase in protein synthesis. The stimulatory effect of endothelin on protein synthesis could be partially blocked by 1-(5-isoquinolinylsulfonyl)-2-methylpiperazine, a protein kinase C inhibitor. Atrial natriuretic factor had no effect on either the basal protein synthesis or protein synthesis stimulated by endothelin. Furthermore, endothelin stimulated RNA synthesis by twofold but had no effect on DNA synthesis in SMC derived from WKY rats. In contrast, SMC derived from spontaneously hypertensive rats showed increased DNA synthesis and cell growth after endothelin stimulation. These studies show that this hormone may play a pivotal role in the development of vascular hypertrophy in hypertension.
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Affiliation(s)
- B H Chua
- Department of Pathology, Wayne State University, Detroit, Michigan 48201
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17
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Abstract
The genetically diabetic db/db mouse is an excellent model to study the effect of diabetes on hormone receptors. The decrease of EGF binding sites could be detected in the hepatic microsomes of diabetic mice as early as 3 weeks of age. In addition, there was an age-related decrease in the autophosphorylating activity of EGF receptor isolated from the liver of diabetic mice. Estrone feeding (0.005%) partially restored this autophosphorylating activity. Northern blot analysis showed that the hepatic EGF receptor transcripts were dramatically decreased during the progression of diabetes and could be reversed by estrone feeding. Transfection experiments carried out on HepG2 cells using EGF receptor promoter (pERCAT-6) demonstrated that addition of 2 x 10(-8) M estrone stimulated chloramphenicol acetyltransferase activity. Our results suggest that estrone modulates EGF receptor by enhancing EGF receptor transcripts and the promoter activity of this gene.
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Affiliation(s)
- B H Chua
- Department of Pathology, Wayne State University, School of Medicine, Detroit, MI 48202
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18
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Abstract
Using human heart fibroblasts (HHF), we studied the effect of basic fibroblast growth factor (bFGF) and transforming growth factor-beta (TGF-beta) on the gene expression of type I collagen, collagenase and tissue inhibitor of metalloproteinases (TIMP). Initially, treatment of HHF with bFGF alone (10 ng/ml) resulted in elevated secretion of collagenase into the culture medium. Subsequent treatment of HHF with TGF-beta in combination with bFGF suppressed collagenase secretion. Northern blot analysis reinforced this observation by revealing an enhancement of the steady-state mRNA level of collagenase in response to bFGF. In order to examine if the collagenase gene was affected by bFGF at the transcriptional level, transfection experiments were carried out with a plasmid containing collagenase promoter linked to chloramphenicol acetyltransferase gene (CAT). Basic FGF stimulated CAT activity by four-fold, indicating increased promoter activity whereas the combination of TGF-beta and bFGF resulted in decreased CAT activity. TGF-beta was shown to increase type I collagen and TIMP mRNA levels by 2.5- and 2.1-fold, respectively. These results suggest that TGF-beta and bFGF may play a pivotal role in regulating collagen metabolism in HHF.
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Affiliation(s)
- C C Chua
- Department of Immunology and Microbiology, Wayne State University, Detroit, MI 48201
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19
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Abstract
We demonstrated previously that growth promoting factors in general could induce the secretion of interstitial collagenase into the medium of human fibroblast cells (HF). In this study, the effect of tumor necrosis factor-alpha (TNF-alpha) on the induction of collagenase and tissue inhibitor of metalloproteinases (TIMP) was examined. Stimulation of quiescent HF cells with 10 ng/ml TNF-alpha induced the secretion of Mr 57,000, 52,000 procollagenases into the medium. The collagenase activity was elevated 2.8-fold after TNF-alpha treatment. Northern blot analysis of the steady-state mRNA indicated a tenfold elevation of collagenase transcript after 24 h treatment with 10 ng/ml TNF-alpha. The increase in collagenase mRNA was due to transcriptional activation of collagenase gene activity. TIMP mRNA level increased three-fold after TNF-alpha treatment. The activity of TNF-alpha on collagenase and TIMP induction may play an important role in tissue inflammatory, repair and remodeling processes after wound and injury.
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Affiliation(s)
- C C Chua
- Department of Immunology and Microbiology, Wayne State University, School of Medicine, Detroit, Michigan 48202
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20
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Abstract
Generation of anti-idiotypic antibodies (anti-Id) is a rapid and new approach to produce anti-receptor antibodies without isolation of the receptor. This report describes the production of polyclonal anti-ANF anti-Id antibodies. These antibodies could inhibit the binding of [125I]-ANF to its receptor on aortic smooth muscle cells. Immunoblot analysis of detergent Chaps-solubilized adrenal gland membranes indicated that these anti-Id antibodies could recognize an Mr 130,000 band under nonreducing condition and an Mr 70,000 band under reducing condition. In addition, these antibodies could slightly increase the production of cyclic GMP in aortic smooth muscle cells.
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Affiliation(s)
- B H Chua
- Department of Pathology, Wayne State University, School of Medicine, Detroit, MI 48202
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21
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Conkling PR, Chua CC, Nadler P, Greenberg CS, Doty E, Misukonis MA, Haney AF, Bast RC, Weinberg JB. Clinical trials with human tumor necrosis factor: in vivo and in vitro effects on human mononuclear phagocyte function. Cancer Res 1988; 48:5604-9. [PMID: 3046744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The purpose of this investigation was to understand the biological effects of recombinant human tumor necrosis factor used as therapy for cancer. We studied changes in mononuclear phagocyte function following exposure to this cytokine in vitro or in vivo. Tumor necrosis factor increased phorbol myristate acetate-induced hydrogen peroxide production 8- to 20-fold in peripheral blood monocytes and peritoneal macrophages in vitro in a dose-dependent manner. Similarly, tumor necrosis factor increased phorbol myristate acetate-induced peroxide production 2.3-fold in monocytes isolated from nine patients following an i.v. infusion of this cytokine (40 to 200 micrograms/m2). In addition, tumor necrosis factor induced a 2.3-fold increase in tissue factor-like activity in mononuclear phagocytes in vitro. In vivo, tumor necrosis factor induced a trend toward higher procoagulant activity in monocytes, although this change was not statistically significant. We also noted a trend toward increased activated partial thromboplastin times and the presence of fibrin D-dimer in patients treated with tumor necrosis factor, demonstrating activation of the coagulation and fibrinolytic systems. Thus, in vivo treatment of humans with i.v. recombinant human tumor necrosis factor induced functional changes in mononuclear phagocytes similar to those noted with in vitro treatment.
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Affiliation(s)
- P R Conkling
- Department of Medicine, Veterans Administration Medical Center, Durham, North Carolina
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22
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Chua CC, Greenberg ML, Viau AT, Nucci M, Brenckman WD, Hershfield MS. Use of polyethylene glycol-modified uricase (PEG-uricase) to treat hyperuricemia in a patient with non-Hodgkin lymphoma. Ann Intern Med 1988; 109:114-7. [PMID: 3289428 DOI: 10.7326/0003-4819-109-2-114] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Modification by covalent attachment of monomethoxypolyethylene glycol (PEG) can reduce the immunogenicity and prolong the circulating life of injected enzymes, making their use as therapeutic agents feasible. We report the first clinical use of PEG-modified Arthrobacter protoformiae uricase (PEG-uricase) to treat hyperuricemia in a patient with non-Hodgkin lymphoma and renal insufficiency who was allergic to allopurinol. Two intramuscular injections totaling 3 U/kg body weight during the first 30 hours of treatment lowered the plasma urate level from 910 to 190 mumol/L (15.3 to 3.2 mg/dL), after which a dose of 2 U/kg every 5 to 6 days maintained the plasma urate level at 540 mumol/L (9 mg/dL) or lower. After the injection of PEG-uricase, uricase activity appeared in plasma rapidly, peaking within 24 hours and persisting for approximately 5 days; an inverse relation between plasma uricase activity and plasma urate concentration was noted. The agent was nontoxic and well tolerated. No antibody to either PEG-uricase or unmodified uricase developed over a 3-week period, during which four doses of PEG-uricase were administered. Because of its long circulating life, PEG-uricase is probably a more effective hypouricemic agent than unmodified uricase, which has previously had limited use. As an adjunct to cytolytic therapy for hematologic malignancies when protection from hyperuricemia is needed rapidly, PEG-uricase deserves further study.
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Affiliation(s)
- C C Chua
- Duke University Medical Center, Durham, North Carolina
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23
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Abstract
A number of peptide growth factors have been shown to induce the secretion of type I collagenase into the medium of human fibroblast cultures (Chua et al., 1985). In this study the ability of eye-derived growth factor, lectin and tumor-promoting agents on collagenase induction in human fibroblast cells were examined. These agents were found to be able to induce collagenase production to a similar extent as epidermal growth factor. Dexamethasone at 10-100 nM was found to suppress collagenase induction in human fibroblast cells. The cell-type specificity of this enzyme induction by growth factors was studied by using a human epidermoid carcinoma cell line, A-431. An Mr 55,000 band appeared in the medium of A-431 cells upon 22 h exposure to EGF. Two-dimensional peptide pattern of the Mr 55,000 band in A-431 cells was identical to the counterpart in HF cells. Our results indicated that the induction of collagenase was not unique to human fibroblast cultures.
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Affiliation(s)
- C C Chua
- Department of Immunology and Microbiology, Wayne State University School of Medicine, Detroit, MI 48201
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24
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Chua CC, Ladda RL. Effect of tunicamycin on the biosynthesis of human fibroblast collagenase. Coll Relat Res 1987; 7:285-93. [PMID: 2822343 DOI: 10.1016/s0174-173x(87)80034-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
It is generally accepted that collagenase from human fibroblast cultures consists of two proenzymes (Mr 60,000 and 55,000) and two active forms (Mr 50,000 and 43,000). We demonstrated previously that epidermal growth factor (EGF) as well as a number of other growth factors induced the secretion of procollagenase (Mr 60,000, Mr 55,000) into the medium of human fibroblast cultures (Chua et al., 1985). In the presence of tunicamycin and EGF, the secretion of the larger form of procollagenase was suppressed preferentially with concomitant appearance of a new band, Mr 40,000. This Mr 40,000 band could be specifically immunoprecipitated by antibody raised against human collagenase. By two-dimensional peptide mapping, the Mr 40,000 material appeared to have similar composition as the Mr 60,000 band. In a time course study, the Mr 55,000 procollagenase band was the earliest protein to appear in the medium after 1 hour labeling with [35S]-methionine. The Mr 60,000, 50,000 and 43,000 bands appeared after a 2 hour labeling period. Our results indicate that human collagenases are glycosylated proteins and are synthesized via the dolichol phosphate pathway.
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Affiliation(s)
- C C Chua
- Department of Immunology and Microbiology, Wayne State University School of Medicine, Detroit, MI 48201
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25
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26
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Abstract
Cellular responsiveness to epidermal growth factor (EGF) and the structure of the receptor for epidermal growth factor (EGF-R) were compared in young and senescent human fibroblast (HF) cells. Biosynthetic labeling of HF cells with [35S] methionine followed by immunoprecipitation with EGF-R antibody revealed the presence of Mr 170 000 EGF-R in cells from both stages. Autophosphorylation of EGF-R in response to EGF was identical in young and senescent cells. Phosphoamino acid analysis of the autophosphorylated EGF-R indicated that tyrosine residues were phosphorylated in each preparation. Two-dimensional peptide mapping of [125I]EGF-R from young and senescent cells showed essentially the same pattern, indicating that EGF-R does not apparently undergo detectable changes in senescent human fibroblasts. The responsiveness of aging HF cells to EGF for the induction of ornithine decarboxylase activity and for the production of secretory proteins was measured. Young and senescent HF cells showed about a three-fold induction of collagenase activity upon addition of EGF. Ornithine decarboxylase activity was also stimulated by EGF to a comparable level in young and senescent cells. Our results indicate that the responsiveness of HF cells to EGF for these two biochemical parameters does not decline with the loss of proliferative activity.
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27
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Chua CC, Geiman DE, Keller GH, Ladda RL. Induction of collagenase secretion in human fibroblast cultures by growth promoting factors. J Biol Chem 1985; 260:5213-6. [PMID: 2985581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
In human foreskin fibroblast cultures, two proteins with Mr 60,000 and 55,000 were found to be induced about 3.5-fold by epidermal growth factor (EGF), platelet-derived growth factor, and beta-transforming growth factor. The induced proteins were identified as procollagenases by immunoprecipitation of induced medium with antibodies to purified human fibroblast collagenase. Collagenase enzyme activity in the medium from EGF-treated cultures was also induced at least 3-fold compared to control cultures. Induction of collagenase was dependent upon de novo protein and RNA synthesis and was observed in the medium 10 h after addition of EGF. Although these growth-promoting factors interact with separate membrane receptors, each induced the secretion of a common protein, suggesting that collagenase may be important in some aspect of mitogenesis, cell mobilization, and migration.
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28
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Chua CC, Geiman DE, Keller GH, Ladda RL. Induction of collagenase secretion in human fibroblast cultures by growth promoting factors. J Biol Chem 1985. [DOI: 10.1016/s0021-9258(18)89004-4] [Citation(s) in RCA: 127] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Chua CC, Geiman DE, Schreiber AB, Ladda RL. Nonfunctional epidermal growth factor receptor in cells transformed by Kirsten sarcoma virus. Biochem Biophys Res Commun 1984; 118:538-47. [PMID: 6322750 DOI: 10.1016/0006-291x(84)91336-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The cell membrane receptor for epidermal growth factor (EGF) appears to be a glycoprotein of Mr 170,000 and mediates the mitogenic and metabolic responses of cells with EGF receptors (EGF-R). Normal rat kidney (NRK) have about 3 X 10(5) EGF-R per cell. Upon transformation of NRK cells by Kirsten sarcoma virus, the transformed derivative (KNRK) loses the ability to bind 125I-EGF. Membranes from NRK and KNRK cells were included in EGF-dependent phosphorylation reactions to search for evidence of the EGF-R. A phosphorylated protein of Mr 170,000 was detected in both NRK and KNRK membranes. The Mr 170,000 protein was identified to be EGF-R by immunoprecipitation with monoclonal antibody to the receptor. Furthermore, two-dimensional peptide mapping using trypsin and chymotrypsin digestions of the iodinated receptors from both NRK and KNRK cells showed essentially identical patterns. These data indicate that the EGF-R is present in KNRK cells with apparently the same protein structure as the NRK counterpart.
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Chua CC, Geiman D, Ladda RL. Transforming growth factors released from Kirsten sarcoma virus transformed cells do not compete for epidermal growth factor membrane receptors. J Cell Physiol 1983; 117:116-22. [PMID: 6311845 DOI: 10.1002/jcp.1041170116] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Kirsten murine sarcoma virus (KiMSV)-transformed rat kidney cells (KNRK) release small polypeptides (Mr 12,500-15,300) into the culture medium that are capable of stimulating normal rat kidney cells (NRK) to form colonies in soft agar. The transforming growth factors (TGFs) did not compete with epidermal growth factor (EGF) for its receptor and did not induce specific phosphorylation of EGF receptor on NRK cell membranes. These properties differ from the TGFs isolated by other investigators. Our data further establish the heterogeneity of the materials produced by transformed cells that induce transformation-specific changes in normal cells.
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Chua CC, Geiman DE, Ladda RL. Detection of an Mr 200,000 glycoprotein in the culture medium of skin fibroblasts from patients with Huntington disease. Biochem Biophys Res Commun 1983; 111:690-9. [PMID: 6220707 DOI: 10.1016/0006-291x(83)90361-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Huntington disease is a progressive neurological disorder with an autosomal dominant mode of inheritance. Using high resolution two-dimensional gel electrophoresis, we analyzed the intracellular and the released protein patterns of skin fibroblasts from HD patients and compared them to cells from apparently normal individuals matched for age and sex. No consistent differences were found in the pattern of total cellular proteins. In contrast, the culture medium from HD patients (12 of 19) contained an Mr 200,000 glycoprotein not found in twelve control cultures. The relation of this protein to the HD gene is unknown.
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Abstract
Nuclear and cytoplasmic RNAs, synthesized in cells productively infected with human cytomegalovirus (HCMV) were analysed at various times after infection by liquid and filter DNA-RNA hybridization. Results of these experiments have revealed that: (i) the fraction of the genome transcribed increased as infection progressed. In the nucleus, transcripts represented approx. 20% of the virus DNA sequences at both 2 and 4 h post-infection (p.i.) and 36% of the virus DNA at 40 h p.i; (ii) the increase in virus sequences among nuclear transcripts at late times was prevented by the DNA synthesis inhibitor, 2'-deoxyfluorouridine; (iii) early virus RNA transcripts were subset of those represented in late RNA; (iv) two classes of early RNA were identified by competition hybridization; (v) approx. 10% of the late nuclear transcripts were symmetrical. Results of filter hybridization at DNA excess indicated that virus-specific RNA represented 0.6% of RNA labelled from 0 to 2 h p.i., and 1.8% of RNA labelled from 28 to 30 h. Polyadenylated RNA isolated from cytoplasm represented 1.2% and 10% of labelled mRNA at 2 h and 30 h respectively. Our data show that during productive infection of human cells by HCMV, gene expression is under temporal, quantitative and post-transcriptional control.
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Hixson SH, Brownie TF, Chua CC, Crapster BB, Satlin LM, Hixson SS, Boyce CO, Ehrich M, Novak EK. Bifunctional aryl azides as probes of the active sites of enzymes. Ann N Y Acad Sci 1980; 346:104-14. [PMID: 6770736 DOI: 10.1111/j.1749-6632.1980.tb22094.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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