Single perivascular delivery of mitomycin C stimulates p21 expression and inhibits neointima formation in rat arteries.
OBJECTIVE
Mitomycin C (MMc) is an antibiotic that exerts a potent antiproliferative effect in tumor cells. Because the proliferation of vascular smooth muscle cells (VSMCs) plays a prominent role in the development of restenosis after percutaneous coronary interventions, the present study examined the effect of MMc on VSMC proliferation and on neointima formation after arterial balloon injury.


RESULTS
Treatment of cultured rat aortic VSMCs with MMc (1 nmol to 30 micromol/L) inhibited VSMC proliferation in a concentration-dependent manner. Whereas high concentrations of MMc (1 to 30 micromol/L) induced VSMC apoptosis, as reflected by DNA laddering and caspase-3 activation, lower concentrations of MMc (1 to 300 nmol/L) directly inhibited VSMC growth by arresting cells in the G2/M phase of the cell cycle. The antiproliferative action of MMc was associated with a selective increase in the expression of the cyclin-dependent kinase inhibitor p21, and with a decrease in cyclin B1-cyclin-dependent kinase-1 complex activity. Finally, the local perivascular delivery of MMc immediately after balloon injury of rat carotid arteries induced p21 expression and markedly attenuated neointima formation.


CONCLUSIONS
These studies demonstrate that MMc exerts a potent inhibitory effect on VSMC proliferation and neointima formation after arterial injury. MMc represents a potentially new therapeutic agent in treating and preventing vasculoproliferative disease.
Granada
Juan F
JF
The Methodist Research Institute, Houston, Texas, USA.
Ensenat
Diana
D
Keswani
Amit N
AN
Kaluza
Grzegorz L
GL
Raizner
Albert E
AE
Liu
Xiao-ming
XM
Peyton
Kelly J
KJ
Azam
Mohammed A
MA
Wang
Hong
H
Durante
William
W
D000800:Angioplasty, Balloon / Q000009:adverse effects*; D000818:Animals; D000903:Antibiotics, Antineoplastic / Q000494:pharmacology*; D001013:Aorta, Thoracic / Q000293:injuries / Q000473:pathology; D001018:Aortic Diseases / Q000188:drug therapy* / Q000209:etiology / Q000473:pathology; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000235:genetics* / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D016685:Mitomycin / Q000494:pharmacology*; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D017539:Tunica Intima / Q000473:pathology
D000903:Antibiotics, Antineoplastic; D050759:Cyclin-Dependent Kinase Inhibitor p21; D012333:RNA, Messenger; D016685:Mitomycin