Background-The haplotypes in the gene vitamin K epoxide reductase complex subunit 1 (VKORC1) have been found to affect warfarin dose response through effects on the formation of reduced-form vitamin K, a cofactor for ␥-carboxylation of vitamin K-dependent proteins, which is involved in the coagulation cascade and has a potential impact on atherosclerosis. We hypothesized that VKORC1-dependent effects on the coagulation cascade and atherosclerosis would contribute to susceptibility for vascular diseases. Methods and Results-To test the hypothesis, we studied the association of polymorphisms of VKORC1 with stroke (1811 patients), coronary heart disease (740 patients), and aortic dissection (253 patients) compared with matched controls (nϭ1811, 740, and 416, respectively). Five common noncoding single-nucleotide polymorphisms of VKORC1 were identified in a natural haplotype block with strong linkage disequilibrium (DЈϾ0.9, r 2 Ͼ0.9), then single-nucleotide polymorphism (SNP) ϩ2255 in the block was selected for the association study. We found that the presence of the C allele of the ϩ2255 locus conferred almost twice the risk of vascular disease (odds ratio [OR] 1.95, 95% confidence interval [CI] .58 to 2.41, PϽ0.001 for stroke; OR 1.72, 95% CI 1.24 to 2.38, PϽ0.01 for coronary heart disease; and OR 1.90, 95% CI 1.04 to 3.48, PϽ0.05 for aortic dissection). We also observed that subjects with the CC and CT genotypes had lower levels of undercarboxylated osteocalcin (a regulator for the bone), probably vascular calcification, and lower levels of protein induced in vitamin K absence or antagonism II (PIVKA-II, a des-␥-carboxy prothrombin) than those with TT genotypes. Conclusions-The haplotype of VKORC1 may serve as a novel genetic marker for the risk of stroke, coronary heart disease, and aortic dissection.

Objective-Migration of vascular smooth muscle cells (VSMCs) from media to intima is a key event in the pathophysiology of atherosclerosis and restenosis. The lipoxygenase products of polyunsaturated fatty acids (PUFA) were shown to play a role in these diseases. cAMP response element binding protein (CREB) has been implicated in the regulation of VSMC growth and motility in response to thrombin and angiotensin II. The aim of the present study was to test the role of CREB in an oxidized lipid molecule, 15(S)-HETE-induced VSMC migration and neointima formation. Methods and Results-15(S)-HETE stimulated VSMC migration in CREB-dependent manner, as measured by the modified Boyden chamber method. Blockade of MEK1, JNK1, or p38MAPK inhibited 15(S)-HETE-induced CREB phosphorylation and VSMC migration. 15(S)-HETE induced expression and secretion of interleukin-6 (IL-6), as analyzed by RT-PCR and ELISA, respectively. Neutralizing anti-IL-6 antibodies blocked 15(S)-HETE-induced VSMC migration. Dominant-negative mutant-mediated blockade of ERK1/2, JNK1, p38MAPK, or CREB suppressed 15(S)-HETE-induced IL-6 expression in VSMCs. Serial 5Ј deletions and site-directed mutagenesis of IL-6 promoter along with chromatin immunoprecipitation using anti-CREB antibodies showed that cAMP response element is essential for 15(S)-HETE-induced IL-6 expression. Dominant-negative CREB also suppressed balloon injury-induced IL-6 expression, SMC migration from media to intimal region, and neointima formation. Adenovirus-mediated transduction of 15-lipoxygenase 2 (15-LOX2) caused increased production of 15-HETE in VSMCs and enhanced IL-6 expression, SMC migration from media to intimal region, and neointima formation in response to arterial injury. Key Words: cAMP response element binding protein Ⅲ hydroxyeicosatetraenoic acid Ⅲ interleukin-6 Ⅲ vascular smooth muscle cell migration V SMC migration from media to intima plays a determinant role in atherosclerosis and restenosis. [1][2][3] Arachidonic acid (AA) and its oxygenative metabolites, known as eicosanoids, are involved in the maintenance of vascular tone. 4,5 Lipoxygenases (LOXs) are nonheme iron dioxygenases that stereospecifically introduce molecular oxygen into polyunsaturated fatty acids (PUFA) such as AA, resulting in the formation of hydroperoxyeicosatetraenoic acids (HPETEs) which are further converted to hydroxyeicosatetraenoic acids (HETEs). Two LOXs in particular, 15-LOX1 in humans and its closely related ortholog, 12/15-LOX, in mice, as well as 5-LOX that convert AA to HETEs are the prime candidates implicated in atherosclerosis and restenosis. 6 -8 It is known that oxidation of low-density lipoprotein (LDL) is a contributing factor in the pathogenesis of atherosclerosis. 9 -11 Many studies have shown that 15-LOX1 and 12/15-LOX are involved in the oxidation of LDL, and thereby in the pathogenesis of atherosclerosis. 10,11 It was also demonstrated that atherosclerotic arteries express increased levels of 15-LOX1 and its AA product, 15-HETE in rabbits. 12,13 In addition, recently ...