Int J Clin Exp Med 2015;8(11):21487-21496 www.ijcem.com /ISSN:1940-5901/IJCEM0015148
Original Article Association between genetic polymorphism in NFKB1 and NFKBIA and coronary artery disease in a Chinese Han population Hongmei Lai1,2,3*, Qingjie Chen1,3*, Xiaomei Li1,3, Yitong Ma1,3, Rui Xu1,3*, Hui Zhai1,3, Fen Liu3,4, Bangdang Chen3,4, Yining Yang1,3 Department of Cardiology, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, China; 2Department of Cardiology, People’s Hospital of Xinjiang Uygur Autonomous Region, Urumqi, China; 3Xinjiang Key Laboratory of Cardiovascular Disease Research, Urumqi, China; 4Clinical Research Institute of Xinjiang Medical University, Urumqi, China. *Equal contributors. 1
Received August 27, 2015; Accepted October 27, 2015; Epub November 15, 2015; Published November 30, 2015 Abstract: Objectives: Prior studies have demonstrated NF-κB plays an important role in the development and progression of inflammatory diseases. The aim of this study was to investigate whether promoter polymorphisms in NFKB1 and NFKBIA gene are associated with coronary artery disease (CAD) in a Chinese Han population. Methods: A total of 1140 Han CAD patients and 1156 Han control subjects were genotyped for 4 single-nucleotide polymorphisms (SNPs) in the promoter region of NFKBIA gene (rs3138053, rs2233406, rs2233409) and NFKB1 gene (-94 ins/del ATTG, rs28362491) by using the TaqMan SNP genotyping assays, and then NFKBIA haplotype blocks were reconstructed according to our genotyping data. Results: For total, men, and women, the distribution of genotypes, alleles of rs3138053, rs2233406, rs2233409 and haplotype polymorphisms showed no significant difference between CAD cases and controls. None of the studied NFKBIA SNPs were associated with CAD. For total, men, and women, there was significant difference in the distribution of the genotypes (P=0.001, P=0.024, P= 0.022) and alleles (P=0.001, P=0.012, P=0.031) of rs28362491 in CAD cases and controls. For total, men, and women, the rs28362491 was associated with increased risk of CAD in a recessive model after adjustment for covariates (OR=1.505, 95% CI 1.190 to 1.903, P=0.001; OR=1.469, 95% CI 1.082-1.993, P=0.014; OR=1.622, 95% CI 1.118 to 2.352, P=0.011, respectively). Conclusions: In our study, the -94 ins/del ATTG polymorphism in NFKB1 promoter is associated with CAD susceptibility in Chinese Han population, providing a new insight into the genetics of CAD in Chinese Han population. Keywords: Coronary artery disease, NFKB1 and NFKBIA polymorphism, Chinese Han population
The prevalence of coronary artery disease (CAD) has been steadily increasing in China during the past several years. CAD and its main complications are the major causes of morbidity and mortality in China. Epidemiological studies have identified many risk factors for CAD, including age, gender, hypertension, diabetes, smoking, family history, dyslipidemia, and sedentary lifestyle, etc. However, these conventional risk factors can only explain minority of the etiology of CAD, indicating that genetic variation play a role in the inter-individual variation in CAD.
studies have identified several genetic polymorphisms in genes encoding pro- and anti-inflammatory cytokines have been associated with atherosclerotic cardiovascular disease [1-4]. The nuclear factor kappa B (NF-κB) family of transcription factors is the major mediator of inflammation, including Rel-A (p65), Rel-B, c-Rel, NF-κB1 (p50), NF-κB2 (p52) [5-7]. NF-κB functions as different complexes of either homodimers or heterodimers, with p65/p50 heterodimer being the most abundant complex and primary inflammatory mediator [6]. NF-κB regulated about 200 target genes, most of them are implicated in inflammation.
Inflammation is involved in the development and progression of atherosclerosis. Recent
In humans, NFkB1 gene, located on chromosome 4q24, encodes p50 protein. P50 has
Introduction
NFKB1, NFKBIA gene and coronary artery disease anti-inflammatory properties in the p50 homodimer (p50/p50) by stimulating transcription of anti-inflammatory cytokines like IL-10, while it has proinflammatory effects as part of the p65/p50 heterodimer by increasing transcription of proinflammatory cytokines like TNF and IL-12. The genetic mutation in the promoter region (NFKB1-94 ins/del ATTG) affect the synthesis of p50. Deletion of one ATTG repeat in the promoter region of NFKB1 gene results in lower transcript levels and less p50 synthesis. In resting cells, NF-κB is sequestered in the cytoplasm by binding to inhibitory proteins of κB family (IκBs), which prevent NF-κB nuclear localization, activation, and inhibit nuclear accumulation. IκBα, encoded by the NFKBIA, is the most abundant and critical inhibitor of NF-κB [8, 9]. Upon stimulation, IκBα is degraded, thus unmasking the NF-κB nuclear localization sequence, then freed NF-κB translocate into the nucleus, where it initiates the transcription of proinflammatory genes. In recent years, many studies have demonstrated that polymorphisms in the promoter region of NFKB1 and NFKBIA gene (NFKB1-94 ins/del ATTG, rs28362491; NFKBIA -881A/G, rs3138053; -826C/T, rs2233406; -297C/T, rs2233409) were associated with many inflammatory diseases risk, such as Grave’s disease, Behcet’s disease, systemic lupus erythematosus, and Crohn’s disease [10-13]. Considering the important role played by NF-κB in regulating inflammation response, it raises hypothesis that genetic variation in the promoter region of NFKB1 and NFKBIA gene could be related to the CAD susceptibility. Therefore, the aim of this study was to investigate whether the functional promoter polymorphisms in NFKB1 and NFKBIA gene are associated with CAD in a Chinese Han population. Methods Study design and population This study was a case-control association study conducted at the First Affiliated Hospital of Xinjiang Medical University. A total of 1140 Han patients aged ≥18 diagnosed with CAD at the First Affiliated Hospital of Xinjiang Medical University between January 2008 and December 2014 were enrolled, including 520 women and 620 men. CAD was defined as the
21488
presence of at least one significant coronary artery stenosis of more than 50% luminal diameter on coronary angiography. Exclusion criteria were patients who have incomplete inhospital data collection; patients with concomitant congenital heart disease, valvular heart disease, and/or non-ischaemic cardiomyopathy. We randomly sampled 1156 ethnic and geographic group-matched participants for the control group. All control subjects were obtained from the Cardiovascular Risk Survey (CRS) study and represented a selection of healthy subjects who had previously provided peripheral blood for the extraction of DNA. CRS study has previously been described in detail [13, 14]. Control subjects were exposed to the same risk profile of CAD, some have hypertension, and/or DM, and/or hyperlipidemia. Exclusion criteria were: a history of CAD; electrocardiographic signs of CAD; regional wall motion abnormalities; relevant valvular abnormalities in echocardiograms and/or carotid atherogenesis [15]. The present study complies with the Declaration of Helsinki. This study protocol was approved by the Ethics Committee of the First Affiliated Hospital of Xinjiang Medical University, and all participants provided written informed consent to participate in genetic research. Definition of cardiovascular risk factors Hypertension was defined as blood pressure levels of 140/90 mmHg or higher or use of antihypertensive medications. Participants were considered diabetic if they reported a physician diagnosis of diabetes or were taking anti-diabetic medication or had fasting/non-fasting glucose ≥126 mg/dL/≥200 mg/dL. Weight and height were used to calculate body mass index (BMI) as weight in kilograms divided by height in meters squared. Persons reporting regular tobacco use in the previous 6 months were considered as current smokers. Biochemical analysis and DNA extraction Fasting peripheral blood samples were obtained from all participants following admission for biochemical analysis. Total cholesterol (TC), Low density lipoprotein (LDL), High density lipoprotein (HDL), and Triglycerides (TG) were measured using standard enzymatic methods
Int J Clin Exp Med 2015;8(11):21487-21496
NFKB1, NFKBIA gene and coronary artery disease Table 1. Basic clinical characteristics of study population according to CAD status Total Number (n)
CAD
Controls
1140
1156
Men P value
CAD
Controls
620
636
58.13±9.55
57.65±9.37
Women P value
CAD
Controls
520
520
0.371
62.13±7.17
61.50±7.35
P value
Age (years)
59.95±8.77
59.38±8.73
0.119
Sex (male, %)
620 (54.4%)
636 (55.0%)
0.769
BMI (kg/m2)
25.78±2.22
25.46±2.41
0.001*
26.16±1.66
25.90±1.88
0.009*
25.32±2.68
24.92±2.84
0.019*
TG (mmol/L)
1.58±0.51
1.51±0.53
0.001*
1.60±0.55
1.52±0.54
0.014*
1.56±0.45
1.49±0.52
0.012*
TC (mmol/L)
4.60±0.74
4.40±0.64
Original Article Association between genetic polymorphism in NFKB1 and NFKBIA and coronary artery disease in a Chinese Han population Hongmei Lai1,2,3*, Qingjie Chen1,3*, Xiaomei Li1,3, Yitong Ma1,3, Rui Xu1,3*, Hui Zhai1,3, Fen Liu3,4, Bangdang Chen3,4, Yining Yang1,3 Department of Cardiology, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, China; 2Department of Cardiology, People’s Hospital of Xinjiang Uygur Autonomous Region, Urumqi, China; 3Xinjiang Key Laboratory of Cardiovascular Disease Research, Urumqi, China; 4Clinical Research Institute of Xinjiang Medical University, Urumqi, China. *Equal contributors. 1
Received August 27, 2015; Accepted October 27, 2015; Epub November 15, 2015; Published November 30, 2015 Abstract: Objectives: Prior studies have demonstrated NF-κB plays an important role in the development and progression of inflammatory diseases. The aim of this study was to investigate whether promoter polymorphisms in NFKB1 and NFKBIA gene are associated with coronary artery disease (CAD) in a Chinese Han population. Methods: A total of 1140 Han CAD patients and 1156 Han control subjects were genotyped for 4 single-nucleotide polymorphisms (SNPs) in the promoter region of NFKBIA gene (rs3138053, rs2233406, rs2233409) and NFKB1 gene (-94 ins/del ATTG, rs28362491) by using the TaqMan SNP genotyping assays, and then NFKBIA haplotype blocks were reconstructed according to our genotyping data. Results: For total, men, and women, the distribution of genotypes, alleles of rs3138053, rs2233406, rs2233409 and haplotype polymorphisms showed no significant difference between CAD cases and controls. None of the studied NFKBIA SNPs were associated with CAD. For total, men, and women, there was significant difference in the distribution of the genotypes (P=0.001, P=0.024, P= 0.022) and alleles (P=0.001, P=0.012, P=0.031) of rs28362491 in CAD cases and controls. For total, men, and women, the rs28362491 was associated with increased risk of CAD in a recessive model after adjustment for covariates (OR=1.505, 95% CI 1.190 to 1.903, P=0.001; OR=1.469, 95% CI 1.082-1.993, P=0.014; OR=1.622, 95% CI 1.118 to 2.352, P=0.011, respectively). Conclusions: In our study, the -94 ins/del ATTG polymorphism in NFKB1 promoter is associated with CAD susceptibility in Chinese Han population, providing a new insight into the genetics of CAD in Chinese Han population. Keywords: Coronary artery disease, NFKB1 and NFKBIA polymorphism, Chinese Han population
The prevalence of coronary artery disease (CAD) has been steadily increasing in China during the past several years. CAD and its main complications are the major causes of morbidity and mortality in China. Epidemiological studies have identified many risk factors for CAD, including age, gender, hypertension, diabetes, smoking, family history, dyslipidemia, and sedentary lifestyle, etc. However, these conventional risk factors can only explain minority of the etiology of CAD, indicating that genetic variation play a role in the inter-individual variation in CAD.
studies have identified several genetic polymorphisms in genes encoding pro- and anti-inflammatory cytokines have been associated with atherosclerotic cardiovascular disease [1-4]. The nuclear factor kappa B (NF-κB) family of transcription factors is the major mediator of inflammation, including Rel-A (p65), Rel-B, c-Rel, NF-κB1 (p50), NF-κB2 (p52) [5-7]. NF-κB functions as different complexes of either homodimers or heterodimers, with p65/p50 heterodimer being the most abundant complex and primary inflammatory mediator [6]. NF-κB regulated about 200 target genes, most of them are implicated in inflammation.
Inflammation is involved in the development and progression of atherosclerosis. Recent
In humans, NFkB1 gene, located on chromosome 4q24, encodes p50 protein. P50 has
Introduction
NFKB1, NFKBIA gene and coronary artery disease anti-inflammatory properties in the p50 homodimer (p50/p50) by stimulating transcription of anti-inflammatory cytokines like IL-10, while it has proinflammatory effects as part of the p65/p50 heterodimer by increasing transcription of proinflammatory cytokines like TNF and IL-12. The genetic mutation in the promoter region (NFKB1-94 ins/del ATTG) affect the synthesis of p50. Deletion of one ATTG repeat in the promoter region of NFKB1 gene results in lower transcript levels and less p50 synthesis. In resting cells, NF-κB is sequestered in the cytoplasm by binding to inhibitory proteins of κB family (IκBs), which prevent NF-κB nuclear localization, activation, and inhibit nuclear accumulation. IκBα, encoded by the NFKBIA, is the most abundant and critical inhibitor of NF-κB [8, 9]. Upon stimulation, IκBα is degraded, thus unmasking the NF-κB nuclear localization sequence, then freed NF-κB translocate into the nucleus, where it initiates the transcription of proinflammatory genes. In recent years, many studies have demonstrated that polymorphisms in the promoter region of NFKB1 and NFKBIA gene (NFKB1-94 ins/del ATTG, rs28362491; NFKBIA -881A/G, rs3138053; -826C/T, rs2233406; -297C/T, rs2233409) were associated with many inflammatory diseases risk, such as Grave’s disease, Behcet’s disease, systemic lupus erythematosus, and Crohn’s disease [10-13]. Considering the important role played by NF-κB in regulating inflammation response, it raises hypothesis that genetic variation in the promoter region of NFKB1 and NFKBIA gene could be related to the CAD susceptibility. Therefore, the aim of this study was to investigate whether the functional promoter polymorphisms in NFKB1 and NFKBIA gene are associated with CAD in a Chinese Han population. Methods Study design and population This study was a case-control association study conducted at the First Affiliated Hospital of Xinjiang Medical University. A total of 1140 Han patients aged ≥18 diagnosed with CAD at the First Affiliated Hospital of Xinjiang Medical University between January 2008 and December 2014 were enrolled, including 520 women and 620 men. CAD was defined as the
21488
presence of at least one significant coronary artery stenosis of more than 50% luminal diameter on coronary angiography. Exclusion criteria were patients who have incomplete inhospital data collection; patients with concomitant congenital heart disease, valvular heart disease, and/or non-ischaemic cardiomyopathy. We randomly sampled 1156 ethnic and geographic group-matched participants for the control group. All control subjects were obtained from the Cardiovascular Risk Survey (CRS) study and represented a selection of healthy subjects who had previously provided peripheral blood for the extraction of DNA. CRS study has previously been described in detail [13, 14]. Control subjects were exposed to the same risk profile of CAD, some have hypertension, and/or DM, and/or hyperlipidemia. Exclusion criteria were: a history of CAD; electrocardiographic signs of CAD; regional wall motion abnormalities; relevant valvular abnormalities in echocardiograms and/or carotid atherogenesis [15]. The present study complies with the Declaration of Helsinki. This study protocol was approved by the Ethics Committee of the First Affiliated Hospital of Xinjiang Medical University, and all participants provided written informed consent to participate in genetic research. Definition of cardiovascular risk factors Hypertension was defined as blood pressure levels of 140/90 mmHg or higher or use of antihypertensive medications. Participants were considered diabetic if they reported a physician diagnosis of diabetes or were taking anti-diabetic medication or had fasting/non-fasting glucose ≥126 mg/dL/≥200 mg/dL. Weight and height were used to calculate body mass index (BMI) as weight in kilograms divided by height in meters squared. Persons reporting regular tobacco use in the previous 6 months were considered as current smokers. Biochemical analysis and DNA extraction Fasting peripheral blood samples were obtained from all participants following admission for biochemical analysis. Total cholesterol (TC), Low density lipoprotein (LDL), High density lipoprotein (HDL), and Triglycerides (TG) were measured using standard enzymatic methods
Int J Clin Exp Med 2015;8(11):21487-21496
NFKB1, NFKBIA gene and coronary artery disease Table 1. Basic clinical characteristics of study population according to CAD status Total Number (n)
CAD
Controls
1140
1156
Men P value
CAD
Controls
620
636
58.13±9.55
57.65±9.37
Women P value
CAD
Controls
520
520
0.371
62.13±7.17
61.50±7.35
P value
Age (years)
59.95±8.77
59.38±8.73
0.119
Sex (male, %)
620 (54.4%)
636 (55.0%)
0.769
BMI (kg/m2)
25.78±2.22
25.46±2.41
0.001*
26.16±1.66
25.90±1.88
0.009*
25.32±2.68
24.92±2.84
0.019*
TG (mmol/L)
1.58±0.51
1.51±0.53
0.001*
1.60±0.55
1.52±0.54
0.014*
1.56±0.45
1.49±0.52
0.012*
TC (mmol/L)
4.60±0.74
4.40±0.64
