EZH2基因多态性与结直肠癌遗传易感性的关联性研究

摘要：目的：探讨EZH2(en hancer of zeste homolog 2)基因单核苷酸多态性（SNPs)与结直肠癌（CRC）遗传易感性的相关性。 方法：用病例-对照方法分析EZH2基因的2个SNPs位点（rs887569与rs1880357）在中南地区汉族人群中的分布。提取96例CRC患者与100例体检健康者的外周血DNA;用聚合酶链式反应-限制性片段长度多态性法（PCR-RFLP）检测EZH2基因型并计算相应等位基因频率;DNA测序验证基因分型结果。 结果：CRC组与健康对照组年龄分布（t=0.693,P=0.489）与性别构成（χ²=0.403,P=0.526）差异无统计学意义。CRC组与健康对照组EZH2基因rs887569位点与rs1880357位点基因频率分布均符合Hardy-Weinberg平衡（P均>0.05）,证明所观察的样本具有群体代表性。EZH2基因rs887569位点TT、CC和TC基因型（χ²=1.531,P=0.465）及rs1880357位点GG、CC和GC基因型（χ²=0.670,P=0.413）在CRC患者和健康对照者间分布差异无统计学意义。对等位基因而言,rs887569位点C>T与rs1880357位点C>G等位基因分布在CRC患者与健康对照者间差异亦无统计学意义（OR=0.875,95%CI:0.488~1.566,P=0.667;OR=0.793,95%CI:0.403~1.563,P=0.503）。 结论：EZH2基因rs887569与rs1880357 SNPs位点多态性可能与CRC发病风险无关。     

E‐selectin expression induced by Porphyromonas gingivalis in human endothelial cells via nucleotide‐binding oligomerization domain‐like receptors and Toll‐like receptors

Porphyromonas gingivalis, an important periodontal pathogen, has been proved to actively invade cells, induce endothelial cell activation, and promote development of atherosclerosis. Innate immune surveillance, which includes the activity of nucleotide‐binding oligomerization domain (NOD)‐like receptors (NLRs) and Toll‐like receptors (TLRs), are essential for the control of microbial infections; however, the roles of receptor families in P. gingivalis infections remain unclear. Here, we examined the roles of NLRs and TLRs in endothelial cell activation caused by P. gingivalis. Live P. gingivalis and whole cell sonicates were used to stimulate endothelial cells, and both showed upregulation of E‐selectin as well as NOD1, NOD2, and TLR2. In addition, silencing of these genes in endothelial cells infected with P. gingivalis led to a reduction in E‐selectin expression. Porphyromonas gingivalis also induced nuclear factor‐κB (NF‐κB) and P38 mitogen‐activated protein kinase (MAPK) activity in endothelial cells, whereas small interfering RNA targeting NOD1 significantly reduced these signals. Moreover, inhibition of either NOD2 or TLR2 inhibited NF‐κB significantly, but had only a weak inhibitory effect on P38 MAPK signaling. Direct inhibition of NF‐κB and P38 MAPK significantly attenuated E‐selectin expression induced by P. gingivalis in endothelial cells. Taken together, these findings suggest that NOD1, NOD2, and TLR2 play important, non‐redundant roles in endothelial cell activation following P. gingivalis infection.     

ABCG1基因启动子区多态性与中国南方汉族人群冠心病多支血管病变的相关性

目的：探讨中国南方汉族人群三磷酸腺苷结合盒转运体G1（ ATP binding cassette transporter G1, ABCG1）基因启动子区单核苷酸多态性与冠心病（ coronary artery disease , CAD）的相关性。方法采用病例对照研究,采用单碱基引物延伸的多重PCR法检测482例冠状动脉造影证实的CAD患者和513例对照者的ABCG1基因启动子区域rs1378577位点A／C多态性,分析该位点多态性与中国南方汉族人群CAD易感性和病变血管数的关系。结果 rs1378577 A／C等位基因和基因型频率在CAD组和对照组之间的分布比较差异无统计学意义（ P＞0.05）;校正了性别、年龄、吸烟状况、高血压、高脂血症、糖尿病等危险因素后, rs1378577 A／C基因多态性与CAD无相关性（ P＞0.05）;rs1378577 A／C多态性在CAD单支病变和多支病变之间的分布比较差异无统计学意义（ P＞0.05）;逻辑回归分析显示,以AA vs AC＋CC分析时rs1378577 A／C多态性可能与冠状动脉病变血管数相关（OR 0.724,95％CI 0.526～0.995,P＝0.047）。结论 ABCG1基因启动子区rs1378577位点A／C多态性可能与中国南方汉族人群冠心病多支血管病变相关。     

SOD2基因多态性与突发性耳聋的遗传易感性研究

目的：探讨人线粒体超氧化物歧化酶2(mitochondrial superoxide dismutase 2, SOD2)基因多态性与云南地区突发性耳聋(idiopathic sensorineural hearing loss, SSNHL)患者遗传易感性的关系。方法采用病例-对照研究,选取78例(男35,女43)突发性耳聋患者和与之性别、年龄相匹配的85例(男39,女46)对照群体,对 SOD2基因的3个标签 SNP 位点(rs5746136、 rs2842960、 rs4880)进行基因分型,统计并分析了基因频率和基因型频率分布与突发性耳聋的遗传易感性的关系。结果在 rs5746136位点(OR ＝2.136,95％ CI ＝1.147~3.978, P ＝0.016)上的 A/ G 基因型可能是中国突发性耳聋患者的危险基因型,而 rs2842960和 rs4880则和中国突发性耳聋患者无相关性;结论 SOD2基因多态位点 rs5746136 A/ G 基因型可能增加突发性耳聋患者的风险,可以作为预测 SSNHL 患者发病危险及早期防治的的遗传标记。     

635 nm波长激光降低干细胞电离辐射敏感性作用的研究

目的 研究低能激光照射作为提高干细胞抗电离辐射的作用效果.方法 取脐带间充质干细胞(UC-MSCs),分为对照组和实验组(单纯激光照射,单纯γ射线照射,激光照射后γ射线照射组);经635 nm(10 mW/cm2,12 J/cm2)每天2次的剂量照射处理3d,于第3天γ射线照射处理(剂量2Gy)后进行碱性单细胞凝胶电泳检测DNA损伤程度、测定γ射线照射前后细胞内活性和脂质氧化物丙二醛的水平,检测氧化应激相关酶(超氧化物歧化酶(SOD)和过氧化氢酶(CAT))的活性.结果 低能激光联合射线组DNA损伤程度较单纯γ射线照射组明显降低,氧化应激酶活性有一定提高,活性氧水平得到抑制,2组丙二醛产量差异无统计学意义(P＞0.05).结论 635 nm激光照射处理的UC-MSCs抗电离辐射水平有一定的提高,可降低移植细胞的辐射敏感性.     

Addressing the link between paraoxonase-1 gene variants and the incidence of early onset myocardial infarction

Introduction

The enzyme paraoxonase-1 (PON1) represents an endogenous defense mechanism against vascular oxidative stress, thereby contributing to the prevention of atherosclerosis. Several polymorphisms have been reported in the PON1 gene, including Q192R. PON1 phenotype is commonly expressed as the paraoxonase/arylesterase ratio (PON/ARE). The major aim of this study was to investigate the association between PON1 Q192R polymorphism, PON1 phenotypes and the incidence of early-onset acute myocardial infarction (AMI) in Egyptians.

Material and methods

The study subjects consisted of 102 AMI patients and 72 age-matched healthy controls. Genotyping and enzyme activities were determined using PCR-RFLP and kinetic spectrophotometric assays, respectively.

Results

The genotype distribution for the PON1 gene was significantly different between AMI patients (QQ = 38.24%, QR = 49.02%, RR = 12.75%) and controls (QQ = 66.67%, QR = 25%, RR = 8.33%). Allele frequencies were also significantly different between patients (Q = 62.75%, R = 37.25%) and controls (Q = 79.17%, R = 20.83%). The genotypes QR and RR showed higher risk for AMI compared to the homozygous QQ (odds ratio (OR) = 3.231, p < 0.001). The average PON/ARE ratio in MI patients (1.187 ±0.1) did not differ significantly from controls (1.118 ±0.26). However, it showed a significant difference among different genotypes in both AMI patients (QQ = 0.91 ±0.11, QR = 1.09 ±0.11 and RR = 2.65 ±0.4) (p = 0.0002) and controls (QQ = 0.68 ±0.1, QR = 1.07 ±0.11 and RR = 4.89 ±2.84) (p < 0.0001).

Conclusions

PON1 192R allele represents an independent risk factor for early-onset AMI in Egyptians, and PON1 Q192R polymorphism modulates the paraoxonase phenotype.     

Association of the Alu insertion polymorphism in the progesterone receptor gene with breast cancer in a Mexican population

Introduction

The progesterone receptor (PR) gene plays an important role in reproduction-related events. Data on polymorphisms in the PR gene have revealed associations with cancer, particularly for the Alu insertion polymorphism, which has been suggested to affect progesterone receptor function and contribute to tumor promotion in the mammary gland.

Material and methods

We examined the role of the Alu insertion polymorphism in the PR gene by comparing the genotypes of 209 healthy Mexican women with those of 481 Mexican women with breast cancer (BC).

Results

The genotype frequencies observed in the controls and BC patients were 0% and 4% for T2/T2 (Alu insertion), 16% and 21% for T1/T2, and 84% and 75% for T1/T1 (Alu deletion), respectively. The obtained odds ratio (OR) was 1.7, with a 95% confidence interval (95% CI) of 1.1–2.6, p = 0.009, for the T1/T2–T2/T2 genotypes. The association was also evident when the distributions of the T1/T2–T2/T2 genotypes in patients in the following categories were compared: obesity grade II (OR = 1.81, 95% CI: 1.03–3.18, p = 0.039) and the chemotherapy response (OR = 1.91, 95% CI: 1.27–3.067, p = 0.002).

Conclusions

The T1/T2–T2/T2 genotypes of the Alu insertion polymorphism in the PR gene are associated with BC susceptibility in the analyzed Mexican population.     

Toll-like receptor 4 gene polymorphisms and susceptibility to colorectal cancer: a meta-analysis and review

Introduction

Many case-control studies have investigated the association between toll-like receptor 4 (TLR4) Asp299Gly and Thr399Ile polymorphisms and risk of colorectal cancer (CRC). However, published data are still conflicting.

Material and methods

A systematic search was conducted in the electronic databases of PubMed, MEDLINE, EMBASE, Web of Science and CNKI between 2000 and 2014. The associations between TLR4 polymorphisms and CRC susceptibility were assessed by pooled odds ratios (ORs) and 95% confidence intervals (95% CI) in fixed or random effects models.

Results

In total nine case-control studies were identified in this meta-analysis. For TLR4 Asp299Gly polymorphism, 9 studies included 1198 cases and 1290 controls. The GG genotype carriers had higher risk for developing CRC than AA + GA genotype carriers (OR = 1.95, 95% CI: 1.00–3.77, p = 0.05). No association was found in other genetic models (p > 0.05). Analysis stratified by ethnicity showed no association in any genetic models among the Asian or Caucasian population. For TLR4 Thr399Ile polymorphism, 6 studies contained 619 cases and 632 controls. The overall analysis showed significantly increased risk in TT homozygote carriers compared to CC homozygote (OR = 4.99, 95% CI: 1.41–17.65, p = 0.01) and C carriers (TC + CC) (OR = 4.50, 95% CI: 1.27–15.87, p = 0.02). In terms of analyses stratified by race, a significant association was found in each genetic model among the Asian population, rather than the Caucasian group.

Conclusions

The GG homozygote carriers of TLR4 Asp299Gly and TT homozygote carriers of TLR4 Thr399Ile polymorphisms might be correlated with an increased risk of CRC, suggesting they may serve as genetic risk factors for CRC.     

Surfactant protein B gene polymorphisms is associated with risk of bronchopulmonary dysplasia in Chinese Han population

Objective: To investigate the relationship between Surfactant protein B (SP-B) gene polymorphisms and bronchopulmonary dysplasia (BPD) development in preterm infants of China Han ethnic population. Methods: SP-B gene polymorphisms were studied in 134 neonates who were born at < 32 weeks of gestation, with the diagnosis of BPD and in a control group of 168 preterm infants without BPD. Genotyping for SP-B was performed by polymerase chain reaction (PCR) and gene sequencing. Results: In this study, three of the SNP genotypes, -18C/A, 1580C/T and 4564T/C were common identified in SP-B gene. The -18C/A genotype was found to be significantly associated with BPD (χ² = 10.741, P < 0.01), with P < 0.01 for the dominant model (OR = 1.712, 95% CI = 1.228-2.3894) and the allelic model (OR = 1.787, 95% CI = 1.276-2.502). The 1580C/T genotype was found to be associated with BPD (χ² = 7.014, P < 0.05), with P < 0.05 for the dominant model (OR = 0.752, 95% CI = 0.593-0.954) and P < 0.01 for the allelic model (OR = 0.706, 95% CI = 0.548-0.909). The 4564T/C genotypes and alleles were found not to be associated with BPD (χ² = 3.399 and 3.227, P > 0.05). Conclusion: SP-B -18C/A and 1580C/T polymorphisms are associated with BPD. The 1580C/T polymorphism was protective while the -18C/A polymorphism increased the risk for BPD. SP-B 4564T/C polymorphism is not associated with BPD.