p27-p16 Fusion Gene Inhibits Angioplasty-Induced Neointimal Hyperplasia and Coronary Artery Occlusion

Abstract

Abstract-Inhibition of proliferative neointima formed by vascular smooth muscle cells is a potential target in preventing angioplasty-induced restenosis. We have created a potent antiproliferative by fusing the active regions of the p27 and p16 cell cycle inhibitors. Intravascular delivery of a replication-deficient adenoviral vector (AV) encoding this p27-p16 fusion protein, named W9, inhibited balloon injury-induced neointimal hyperplasia in rabbit carotid arteries. In a therapeutically more relevant model, AV-W9 was delivered to balloon-injured porcine coronary arteries in vivo using an infusion catheter. Of the three coronary arteries, two were injured with a 15-mm balloon catheter and either were left untreated or were treated with 10 12 viral particles of either AV-W9 or a control null virus. AV-W9 treatment significantly inhibited neointimal hyperplasia in this porcine arterial balloon injury model compared with untreated or control virus-treated vessels. The average intimal area of the AV-W9 -treated group 10 days after balloon injury and treatment was 0.42Ϯ0.36 mm 2 , whereas the AV-null group demonstrated an intimal area of 0.70Ϯ0.52 mm 2 . At day 10 the average intimal thickness of the AV-W9 -treated vessels was 9.1 m (nϭ5, ϫ20 magnification) compared with 21.2 m (nϭ5, ϫ20 magnification) in control virus-treated vessels. This trend was also observed at 28 days after balloon injury and gene transfer during which AV-W9 -treated vessels demonstrated an average intimal thickness of 4.7 m (nϭ8, ϫ20 magnification) compared with 13.3 m (nϭ3, ϫ20 magnification) in control virus-treated vessels and 7.3 m (nϭ5, ϫ20 magnification) in the sham-treated vessels. The AV-W9 treatment was safe and well tolerated. These data suggest that AV-W9 gene therapy may be useful in preventing angioplasty-induced intimal hyperplasia in the coronary artery. Key Words: p27 Ⅲ p16 Ⅲ restenosis Ⅲ gene therapy V ascular smooth muscle cell (SMC) proliferation is induced in response to the overextension of coronary and peripheral arteries occurring during balloon angioplasty. This hyperproliferative response is believed to be a critical event in the therapy-associated complication of vessel reocclusion resulting from restenosis. Manipulation of the normal cell cycle control mechanisms in vascular SMCs at the angioplasty site has been suggested as a means of preventing the restenosis. [1][2][3][4][5][6][7][8][9][10][11][12] The negative regulators of cell cycle progression, the cyclin-dependent kinase (CDK) inhibitors (CDKis), fall into the following two structurally distinct families: the INK4 family comprising p15, p16, p18, and p19, and the CIP/KIP family comprising p21, p27, and p57. [13][14][15][16][17] Members of the INK4 and CIP/KIP families normally act in concert to regulate cell proliferation. We combined representative members of each family to create more potent cytostatic agents.A series of p27 KIP1 and p16 INK4b fusion genes were created and introduced into the E1 region of an E1-deleted replication-deficient adenoviral vec...

Hemodialysis Vascular Access Dysfunction: From Pathophysiology to Novel Therapies

“…A plethora of inflammatory mediators (all of which could be potential therapeutic targets) have been implicated in these processes. They include a large number of signal transduction molecules (p27 [29], p16 [30] retinoblastoma protein [31], p38 MAP kinase [32]), cytokines (PDGF [33], bFGF [34], and TNF-· [35]), chemokines (MCP-1 [36,37] and RANTES [38]) vasoactive molecules (nitric oxide [39] and endothelin [40]), adhesion molecules (ICAM-1 [41] and P-selectin [42]) and molecules such as osteopontin [43], apolipoprotein E [44], matrix metalloproteinase-2 [45] and human hepatocyte growth factor [46]. Of particular interest are studies in TNF-· [35] and ICAM knockout animals [41], which demonstrate a marked reduction in neointimal hyperplasia in these animals.…”

“…Currently, inhibition of neointimal hyperplasia in experimental angioplasty models has been achieved by the gene transfer of endothelial [95] and inducible [96] nitric oxide synthase, cyclin-dependent kinase inhibitors [97,98], retinoblastoma protein [31], hepatocyte growth factor [46] and transcription factors such as E2F [99].…”

Adenovirus-Mediated Expression of β-Adrenergic Receptor Kinase C-Terminus Reduces Intimal Hyperplasia and Luminal Stenosis of Arteriovenous Polytetrafluoroethylene Grafts in Pigs

“…[7][8][9] Other cytotoxic and cytostatic gene therapy strategies that target neointima formation in general and vascular smooth muscle cells in particular have also shown efficacy for the treatment of smooth muscle proliferative disorders in animal models. 10,[12][13][14][15][16][17][18][19] In the present study, we evaluated the efficacy and safety of adenovirus-mediated expression of ␤ARKct in a pig model of AV PTFE graft failure. Our results suggest that local administration of adenoviral vectors encoding ␤ARKct represents a novel strategy to treat AV graft hemodialysis vascular access failure.…”

Novel Therapies for Hemodialysis Vascular Access Dysfunction: Fact or Fiction!

“…Currently, inhibition of neointimal hyperplasia in experimental angioplasty models has been achieved by the gene transfer of endothelial [32] and inducible [33] nitric oxide synthase, cyclin-dependent kinase inhibitors [34,35] , retinoblastoma protein [36] , hepatocyte growth factor [37] and transcription factors such as E2F [38,39] . A clinical study of the E2F decoy in the setting of hemodialysis vascular access dysfunction will soon be initiated under the sponsorship of Corgentech.…”