Growth suppression of human coronary vascular smooth muscle cells by gene transfer of the transcription factor E2F-1

• Published in: Circulation (New York, N.Y.) Vol. 103; no. 3; pp. 407 - 414
• Main Authors: SHELAT, Harnath S, LIU, Ta-Jen, HICKMAN-BICK, Diane L, BARNHART, Michael K, VIDA, Thomas, DILLARD, Patricia M, WILLERSON, James T, ZOLDHELYI, Pierre
• Format: Journal Article
• Language: English
• Published: Hagerstown, MD Lippincott Williams & Wilkins 23-01-2001; American Heart Association, Inc
• Subjects: Adenoviridae - genetics; Apoptosis; Biological and medical sciences; Carrier Proteins; Caspase 3; Caspases - biosynthesis; Cell Count; Cell Cycle Proteins; Cells, Cultured; Coronary Vessels - cytology; Coronary Vessels - growth & development; Diseases of the cardiovascular system; DNA-Binding Proteins; E2F Transcription Factors; E2F1 Transcription Factor; Enzyme Induction; Flow Cytometry; Genetic Vectors; Humans; Immunohistochemistry; In Situ Nick-End Labeling; Medical sciences; Muscle Development; Muscle, Smooth, Vascular - cytology; Muscle, Smooth, Vascular - growth & development; Radiotherapy. Instrumental treatment. Physiotherapy. Reeducation. Rehabilitation, orthophony, crenotherapy. Diet therapy and various other treatments (general aspects); Retinoblastoma-Binding Protein 1; S Phase; Time Factors; Transcription Factor DP1; Transcription Factors - biosynthesis; Transcription Factors - genetics; Transcription Factors - pharmacology; Transfection; Human; Cell proliferation; Cell culture; Coronary artery; Instrumentation therapy; Smooth muscle; Instrumental dilatation; Genetic transfer; Prevention; Restenosis; Treatment; Gene; Complication; Transcription factor; Apoptosis
• ISSN: 0009-7322; 1524-4539
• DOI: 10.1161/01.cir.103.3.407

The transcription factor E2F-1 promotes S-phase entry and death in transformed cells and primary cardiomyocytes. We tested the hypothesis that overexpression of E2F-1 forces growth-arrested human coronary vascular smooth muscle cells (VSMCs) to enter the S phase, undergo apoptosis, and thereby regulate VSMC growth.
Early-passage (</=5 passages) coronary VSMCs were transduced at an MOI of 100 with a recombinant adenovirus encoding human E2F-1. E2F-1 expression was observed by immunohistochemistry as early as 6 to 8 hours after exposure of the VSMCs to Ad.E2F-1 but not to the control vector Ad.RR. When cells were kept in growth-arrest medium, 40% of Ad.E2F-1-treated VSMCs entered the S phase by 96 hours, whereas the percentage remained <5% in Ad.RR-treated cells. Transition to the S phase in the E2F-1-transduced VSMCs was followed by apoptosis, as reflected by chromatin condensation, membrane blebbing, cell detachment, and loss of mitochondrial membrane integrity. E2F-1 overexpression resulted in positive dUTP nick end-labeling mediated by terminal deoxynucleotidyl transferase, associated with a robust increase in caspase 3-like activity. Four days after infection with Ad.E2F-1, the fraction of hypodiploid VSMCs in subG(1) increased to 75%. At 7 days, gene transfer of E2F-1 had completely suppressed the growth of VSMCs, whereas the number of Ad.RR-infected cells had increased >8 times.
Overexpression of the transcription factor E2F-1 regulates growth of human coronary VSMCs by forcing the cells to enter the S phase and then to die. Cell death appears to involve caspase 3-like activity, which, in the VSMCs, is markedly increased by overexpression of E2F-1.