The Relationship Between EBF1 Gene Polymorphism, Rs10811656 And Coronary Heart Disease And Its Mechanism

Part I.Association in a Chinese population of a genetic variation in the early B-cell factor 1 gene with coronary artery diseaseObjective:Early B-cell factor 1(EBF1)is a transcription factor expressed primarily during early B cell development.Previous studies have shown EBF1 regulates blood glucose and lipid metabolism in mice with diabetes and central adiposity.Recently,a genetic variation(rs36071027)located in an EBF1 gene intron was associated with carotid artery intima-media thickness.However,whether this polymorphism is actually linked with coronary artery disease(CAD)and its severity remains unclear.Methods:This study includes 293 CAD cases and 262 controls without CAD.Coronary angiography was performed on all participants to assign patients to the two groups.A polymerase chain reaction-ligase detection reaction was used to identify genotypes at rs36071027,and CAD patients were further divided into subgroups with one-,two-,or three-vessel stenosis reflective of CAD severity.Results:The frequency of the rs36071027 TT genotype was significantly higher in CAD cases versus controls(4.8%vs.1.5%,95%CI:1.13-10.81 P=0.029).Subjects with a variant genotype T allele had an increased risk of CAD compared to C allele carriers(additive model:95%CI:1.13-2.23,P=0.008).After adjustment for cardiovascular risk factors,analysis of the additive and dominant models involving rs36071027 also revealed that T allele carriers had a significantly higher risk for CAD than C allele carriers(additive model:OR 1.56,95%Cl 1.10-2.22,P=0.013;dominant model:OR 1.60,95%CI 1.07-2.41,P=0.023).Furthermore,both diabetes and the CT+TT rs36071027 genotype were significantly associated with three-vessel stenosis.Conclusion:Our results in a Chinese population suggest that the TT genotype and T alleles in rs36071027 in the EBF1 gene are associated with an increased risk of CAD and its severity.Part Ⅱ.Association of rs10811656 on 9P21.3 with the risk of coronary artery disease in a Chinese populationObjective:Genome-wide association studies have reported that the 9p21.3 locus confers risk for coronary artery disease(CAD).However,it is not known whether rs10811656 is linked with CAD in a Chinese population.Methods:We conducted a hospital-based,case-control study with 251 CAD patients and 304 controls to examine the potential association of rs10811656 with CAD.Results:The frequencies of the TT genotypes in CAD cases were significantly different from those in controls(adjusted OR:1.96,95%CI:1.09-3.505,P=0.024).Compared to controls,rs10811656 was significantly associated with the stable angina pectoris(adjusted OR:1.42,95%CI:1.06-1.90,P=0.017),but not with acute coronary syndrome.There was also a highly significant association of rs10811656 with double-vessel and triple-vessel disease when patients were divided into subgroups based on the number of diseased vessels(adjusted OR:1.68 and 1.60,95%CI:1.14-2.44 and 1.10-2.33,P=0.009 and 0.02,respectively).Conclusions:Our results suggest that the rs10811656 locus might be associated with CAD in a Chinese Han population.Moreover,rs10811656 is correlated with severity of coronay artery rather than actue coronary syndrome(ACS).Among those who are male and smokers,carriers with rs10811656 TT is more predisposed to CAD.Part Ⅲ.The role and mechanism of CDKN2A/2B in alleviating endothelial inflammationObjective:Chronic inflammation is the major cause of endothelial dysfunction which plays crucial role in the development of atherosclerosis.Our previous study indicating that rs10811656 in 9p21.3 locus is associated with the risk of coronary artery disease.CDKN2A/2B is proximal to 9p21.3 locus,and plays important roles in regulating cellular cycle.It has been shown that CDKN2A/2B is involved in the progression of atherosclerosis;however,it remains unclear that whether CDKN2A/2B has effect on the endothelial inflammation.Methods:We constructed Ox-LDL induced endothelial inflammation model in HUVEC cell.CDKN2A/2B adenovirus were treated to study the effect of CDKN2A/2B over-expression on Ox-LDL induced endothelial inflammation and MAPK pathway activation.Moreover,MAPK agonist was used to investigate whether the effects of CDKN2A/2B on endothelial inflammation is mediated by MAPK pathway.Results:Ox-LDL treatment induced increased expression of inflammatory factors including TNF-α,IL-6 and MCP-1.CDKN2A/2B were decreased in Ox-LDL treated cells,while CDKN2A/2B over-expression could alleviate Ox-LDL induced increase of TNF-α,IL-6 and MCP-1.Ox-LDL stimulation promoted phosphorylation of JNK and p38,which could be mitigated by CDKN2A/2B over-expression.However,MAPK agonist Anisomycin could reverse the effect of CDKN2A/2B over-expression,as increased TNF-a,IL-6 and MCP-1.Conclusion:Our results suggest that CDKN2A/2B could alleviate endothelial inflammation,which may be partially mediated by inhibiting the activation of MAPK pathways severity.