AIM: Genetic polymorphism in enzymes of carcinogen metabolism has been found to have the influence on the susceptibility to cancer. Cytochrome P450 2E1 ( CYP2 E1) is considered to play an important role in the metabol...AIM: Genetic polymorphism in enzymes of carcinogen metabolism has been found to have the influence on the susceptibility to cancer. Cytochrome P450 2E1 ( CYP2 E1) is considered to play an important role in the metabolic activation of procarcinogens such as N-nitroscoamines and Iow molecular weight organic compounds. The purpose of this study is to determine whether CYP450 2Elpolymorphisms are associated with risk s of gastric cancer.METHODS: We conducted a population based case-control study in Changle county, Fujian Province, a high-risk region of gastric cancer in China. Ninety-one incident gastric cancer patients and ninety-four healthy controls were included in our study. Datas including dsmographic characteristcs, diet intake, and alcohol and tobacco consumption of indivduals in our study were completed by a standardized questionnaire. PCR-RFLP revealed three genotypes: heterozygote (C1/C2) and two homozygotes (C1/C1 and C2/C2) in CYP2E1.RESULTS: The frequency of variant genotypes (C1/C2 and C2/C2) in gastric cancer cases and controls was 36.3% and 24.5%, respectively. The rare homozygous C2/C2 genotype was found in 6 indivduals in gastric cancer group(6.6%),whereas there was only one in the control group (1.1%).However, there was no statistically significan difference between the two groups (two-tailed Fisher′s exact test, P =0.066). Indivduals in gastric cancer group were more likely to carry genotype C1/C2 (odds ratio, OR = 1.50) and C2/C2(OR = 7.34) than indivduals in control group (X2 = 4.597, for trend P=0.032). The frequencies of genofypes with the C2allele ( C1/C2 and C2/C2 genotypes) were compared with those of genotypes without C2 allele ( C1/C1 genotype )among indivduals in gastric cancer group and control group according to the pattern of gastric cancer risk factors. The results show that indivduals who exposed to these gastric cancer risk factors and carry the C2 allele seemed to have a higher risk of developing gastric cancer.CONCLUSION: Polymorphism of CYP2E1 gene may have some effct in the development of gastric cancer in Changle county, Fujian Province.展开更多
Gastric cancer(GC) is a major public health issue as the fourth most common cancer and the second leading cause of cancer-related death. Recent advances have improved our understanding of its molecular pathogenesis,as...Gastric cancer(GC) is a major public health issue as the fourth most common cancer and the second leading cause of cancer-related death. Recent advances have improved our understanding of its molecular pathogenesis,as best exemplified by elucidating the fundamental role of several major signaling pathways and related molecular derangements. Central to these mechanisms are the genetic and epigenetic alterations in these signaling pathways,such as gene mutations,copy number variants,aberrant gene methylation and histone modification,nucleosome positioning,and microRNAs. Some of these genetic/epigenetic alterations represent effective diagnostic and prognostic biomarkers and therapeutic targets for GC. This information has now opened unprecedented opportunities for better understanding of the molecular mechanisms of gastric carcinogenesis and the development of novel therapeutic strategies for this cancer. The pathogenetic mechanisms of GC are the focus of this review.展开更多
Gastric cancer accounts for the majority cancer-related deaths worldwide.Although various methods have considerably improved the screening,diagnosis,and treatment of gastric cancer,its incidence is still high in Asia,...Gastric cancer accounts for the majority cancer-related deaths worldwide.Although various methods have considerably improved the screening,diagnosis,and treatment of gastric cancer,its incidence is still high in Asia,and the 5-year survival rate of advanced gastric cancer patients is only 10%-20%.Therefore,more effective drugs and better screening strategies are needed for reducing the incidence and mortality of gastric cancer.Cyclooxygenase-2(COX-2)is considered to be the key inducible enzyme in prostaglandins(PGs)synthesis,which is involved in multiple pathways in the inflammatory response.For example,inflammatory cytokines stimulate innate immune responses via Toll-like receptors and nuclear factor-kappa B to induce COX-2/PGE2 pathway.In these processes,the production of an inflammatory microenvironment promotes the occurrence of gastric cancer.Epidemiological studies have also indicated that non-steroidal antiinflammatory drugs can reduce the risk of malignant tumors of the digestive system by blocking the effect of COX-2.However,clinical use of COX-2 inhibitors to prevent or treat gastric cancer may be limited because of potential side effects,especially in the cardiovascular system.Given these side effects and low treatment efficacy,new therapeutic approaches and early screening strategies are urgently needed.Some studies have shown that genetic variation in COX-2 also play an important role in carcinogenesis.However,the genetic variation analysis in these studies is incomplete and isolated,pointing out only a few single nucleotide polymorphisms(SNPs)and the risk of gastric cancer,and no comprehensive study covering the whole gene region has been carried out.In addition,copy number variation(CNV)is not mentioned.In this review,we summarize the SNPs in the whole COX-2 gene sequence,including exons,introns,and both the 5’and 3’untranslated regions.Results suggest that COX-2 does not increase its expression through the CNV and the SNPs in COX-2 may serve as the potential marker to establish risk stratification in the general population.This review synthesizes emerging insights of COX-2 as a biomarker in multiple studies,summarizes the association between whole COX-2 sequence variation and susceptibility to gastric cancer,and discusses the future prospect of therapeutic intervention,which will be helpful for early screening and further research to find new approaches to gastric cancer treatment.展开更多
Objective Cytochrome P450 2E1 （CYP2E1） is an important metabolizing enzyme involved in oxidative stress responses to benzene, a chemical associated with bone marrow toxicity and leukemia, We aimed to identify the CY...Objective Cytochrome P450 2E1 （CYP2E1） is an important metabolizing enzyme involved in oxidative stress responses to benzene, a chemical associated with bone marrow toxicity and leukemia, We aimed to identify the CYP2E1 genetic biomarkers of susceptibility to benzene toxicity in support of environmental and occupational exposure prevention, and to test whether a model using immortal human lymphocytes might be an efficient tool for detecting genetic biomarkers. Methods Immortalized human lymphocyte cell lines with independent genotypes on four CYP2E1 SNP sites were induced with 0.01% phenol, a metabolite of benzene. CYP2E1 gene function was evaluated by mRNA expression and enzyme activity. DNA damage was measured by Single-Cell Gel Electrophoresis （SCGE）. Results Among the four SNPs, cells with rs2070673TT and rs2030920CC showed higher levels of ~YP2E1 transcription and enzymatic activity than the other genotypes in the same SNP site. Cells with higher gene expression genotypes also showed higher comet rates compared with lower gene expression genotypes. Conclusion These results suggest that CYP2E1 rs2070673 and rs2030920 might be the genetic biomarkers of susceptibility to benzene toxicity and that the immortalized human lymphocytes model might be an efficient tool for the detection of genetic biomarkers of susceptibility to chemicals.展开更多
Echinococcosis is a global and zoonotic helminthic disease caused by Echinococcus sp. A 24-year-old woman, coming from Bolivia two years before, was diagnosed as cystic echinococcosis (CE) by unstained wet mount and c...Echinococcosis is a global and zoonotic helminthic disease caused by Echinococcus sp. A 24-year-old woman, coming from Bolivia two years before, was diagnosed as cystic echinococcosis (CE) by unstained wet mount and cytological findings through aspiration cytology from the liver, suggested as liver abscess by diagnostic images. The patient was classified as CE1, smaller than 5 cm, and was diagnosed as P1N0M0, stage I. The phylogenetic trees of Echinococcus spp., based on cox1 genes showed that the isolates on the patient belonged to E. ortleppi. The patient was conservatively treated with two courses of albendazole therapy. E. ortleppi has been reported to be in regions including Latin America, except with Japan. Although the patient came from Bolivia before two years, this is the first case report of E. ortleppi from liver echinococcosis in Japan.展开更多
本研究提取中国东北汉族和达斡尔、鄂伦春、鄂温克等 4个人群的基因组 DNA后 ,利用PCR- RFLP方法扩增 apo E基因第 4外显子片段并进行遗传分析 ,计算各个人群中的 apo E等位基因频率。结果发现 4个人群中的 apo E等位基因频率分布趋势...本研究提取中国东北汉族和达斡尔、鄂伦春、鄂温克等 4个人群的基因组 DNA后 ,利用PCR- RFLP方法扩增 apo E基因第 4外显子片段并进行遗传分析 ,计算各个人群中的 apo E等位基因频率。结果发现 4个人群中的 apo E等位基因频率分布趋势与国内外报告基本一致 ,但等位基因ε3展开更多
基金Supported by Natural Science Foundation of Fujian Province,China,No.C001009
文摘AIM: Genetic polymorphism in enzymes of carcinogen metabolism has been found to have the influence on the susceptibility to cancer. Cytochrome P450 2E1 ( CYP2 E1) is considered to play an important role in the metabolic activation of procarcinogens such as N-nitroscoamines and Iow molecular weight organic compounds. The purpose of this study is to determine whether CYP450 2Elpolymorphisms are associated with risk s of gastric cancer.METHODS: We conducted a population based case-control study in Changle county, Fujian Province, a high-risk region of gastric cancer in China. Ninety-one incident gastric cancer patients and ninety-four healthy controls were included in our study. Datas including dsmographic characteristcs, diet intake, and alcohol and tobacco consumption of indivduals in our study were completed by a standardized questionnaire. PCR-RFLP revealed three genotypes: heterozygote (C1/C2) and two homozygotes (C1/C1 and C2/C2) in CYP2E1.RESULTS: The frequency of variant genotypes (C1/C2 and C2/C2) in gastric cancer cases and controls was 36.3% and 24.5%, respectively. The rare homozygous C2/C2 genotype was found in 6 indivduals in gastric cancer group(6.6%),whereas there was only one in the control group (1.1%).However, there was no statistically significan difference between the two groups (two-tailed Fisher′s exact test, P =0.066). Indivduals in gastric cancer group were more likely to carry genotype C1/C2 (odds ratio, OR = 1.50) and C2/C2(OR = 7.34) than indivduals in control group (X2 = 4.597, for trend P=0.032). The frequencies of genofypes with the C2allele ( C1/C2 and C2/C2 genotypes) were compared with those of genotypes without C2 allele ( C1/C1 genotype )among indivduals in gastric cancer group and control group according to the pattern of gastric cancer risk factors. The results show that indivduals who exposed to these gastric cancer risk factors and carry the C2 allele seemed to have a higher risk of developing gastric cancer.CONCLUSION: Polymorphism of CYP2E1 gene may have some effct in the development of gastric cancer in Changle county, Fujian Province.
基金Supported by National Key Program for Developing Basic Research,No.2010CB933903the National Natural Science Foundation of China,No.81171969,No.81272933 and No.81372217the Fundamental Research Funds for the Central Universities
文摘Gastric cancer(GC) is a major public health issue as the fourth most common cancer and the second leading cause of cancer-related death. Recent advances have improved our understanding of its molecular pathogenesis,as best exemplified by elucidating the fundamental role of several major signaling pathways and related molecular derangements. Central to these mechanisms are the genetic and epigenetic alterations in these signaling pathways,such as gene mutations,copy number variants,aberrant gene methylation and histone modification,nucleosome positioning,and microRNAs. Some of these genetic/epigenetic alterations represent effective diagnostic and prognostic biomarkers and therapeutic targets for GC. This information has now opened unprecedented opportunities for better understanding of the molecular mechanisms of gastric carcinogenesis and the development of novel therapeutic strategies for this cancer. The pathogenetic mechanisms of GC are the focus of this review.
基金Supported by National Natural Science Foundation of China,No.81373097.
文摘Gastric cancer accounts for the majority cancer-related deaths worldwide.Although various methods have considerably improved the screening,diagnosis,and treatment of gastric cancer,its incidence is still high in Asia,and the 5-year survival rate of advanced gastric cancer patients is only 10%-20%.Therefore,more effective drugs and better screening strategies are needed for reducing the incidence and mortality of gastric cancer.Cyclooxygenase-2(COX-2)is considered to be the key inducible enzyme in prostaglandins(PGs)synthesis,which is involved in multiple pathways in the inflammatory response.For example,inflammatory cytokines stimulate innate immune responses via Toll-like receptors and nuclear factor-kappa B to induce COX-2/PGE2 pathway.In these processes,the production of an inflammatory microenvironment promotes the occurrence of gastric cancer.Epidemiological studies have also indicated that non-steroidal antiinflammatory drugs can reduce the risk of malignant tumors of the digestive system by blocking the effect of COX-2.However,clinical use of COX-2 inhibitors to prevent or treat gastric cancer may be limited because of potential side effects,especially in the cardiovascular system.Given these side effects and low treatment efficacy,new therapeutic approaches and early screening strategies are urgently needed.Some studies have shown that genetic variation in COX-2 also play an important role in carcinogenesis.However,the genetic variation analysis in these studies is incomplete and isolated,pointing out only a few single nucleotide polymorphisms(SNPs)and the risk of gastric cancer,and no comprehensive study covering the whole gene region has been carried out.In addition,copy number variation(CNV)is not mentioned.In this review,we summarize the SNPs in the whole COX-2 gene sequence,including exons,introns,and both the 5’and 3’untranslated regions.Results suggest that COX-2 does not increase its expression through the CNV and the SNPs in COX-2 may serve as the potential marker to establish risk stratification in the general population.This review synthesizes emerging insights of COX-2 as a biomarker in multiple studies,summarizes the association between whole COX-2 sequence variation and susceptibility to gastric cancer,and discusses the future prospect of therapeutic intervention,which will be helpful for early screening and further research to find new approaches to gastric cancer treatment.
基金supported by the National Natural Science Foundation of China (Grant No: 30671731, 30901168)the Doctoral Program of Higher Education of China (Grant No: 20070286069)
文摘Objective Cytochrome P450 2E1 （CYP2E1） is an important metabolizing enzyme involved in oxidative stress responses to benzene, a chemical associated with bone marrow toxicity and leukemia, We aimed to identify the CYP2E1 genetic biomarkers of susceptibility to benzene toxicity in support of environmental and occupational exposure prevention, and to test whether a model using immortal human lymphocytes might be an efficient tool for detecting genetic biomarkers. Methods Immortalized human lymphocyte cell lines with independent genotypes on four CYP2E1 SNP sites were induced with 0.01% phenol, a metabolite of benzene. CYP2E1 gene function was evaluated by mRNA expression and enzyme activity. DNA damage was measured by Single-Cell Gel Electrophoresis （SCGE）. Results Among the four SNPs, cells with rs2070673TT and rs2030920CC showed higher levels of ~YP2E1 transcription and enzymatic activity than the other genotypes in the same SNP site. Cells with higher gene expression genotypes also showed higher comet rates compared with lower gene expression genotypes. Conclusion These results suggest that CYP2E1 rs2070673 and rs2030920 might be the genetic biomarkers of susceptibility to benzene toxicity and that the immortalized human lymphocytes model might be an efficient tool for the detection of genetic biomarkers of susceptibility to chemicals.
文摘Echinococcosis is a global and zoonotic helminthic disease caused by Echinococcus sp. A 24-year-old woman, coming from Bolivia two years before, was diagnosed as cystic echinococcosis (CE) by unstained wet mount and cytological findings through aspiration cytology from the liver, suggested as liver abscess by diagnostic images. The patient was classified as CE1, smaller than 5 cm, and was diagnosed as P1N0M0, stage I. The phylogenetic trees of Echinococcus spp., based on cox1 genes showed that the isolates on the patient belonged to E. ortleppi. The patient was conservatively treated with two courses of albendazole therapy. E. ortleppi has been reported to be in regions including Latin America, except with Japan. Although the patient came from Bolivia before two years, this is the first case report of E. ortleppi from liver echinococcosis in Japan.
