The role of polymorphic cytochrome P450 gene(CYP2B6)in B-chronic lymphocytic leukemia(B-CLL)incidence and outcome among Egyptian patients

Cytochromes P450(CYPs)play a prominent role in catalyzing phase I xenobiotic biotransformation and account for about 75%of the total metabolism of commercially available drugs,including chemotherapeutics.The gene expression and enzyme activity of CYPs are variable between individuals,which subsequently leads to different patterns of susceptibility to carcinogenesis by genotoxic xenobiotics,as well as differences in the efficacy and toxicity of clinically used drugs.This research aimed to examine the presence of the CYP2B6*9 polymorphism and its possible association with the incidence of B-CLL in Egyptian patients,as well as the clinical outcome after receiving cyclophosphamide chemotherapy.DNA was isolated from whole blood samples of 100 de novo B-CLL cases and also from 100 sex-and age-matched healthy individuals.The presence of the CYP2B6*9(G516T)polymorphism was examined by PCR-based allele specific amplification(ASA).Patients were further indicated for receiving chemotherapy,and then they were followed up.The CYP2B6*9 variant indicated a statistically significant higher risk of B-CLL under different genetic models,comprising allelic(T-allele vs.G-allele,OR=4.8,p<0.001)and dominant(GT+TT vs.GG,OR=5.4,p<0.001)models.Following cyclophosphamide chemotherapy,we found that the patients with variant genotypes(GT+TT)were less likely to achieve remission compared to those with the wild-type genotype(GG),with a response percentage of(37.5%vs.83%,respectively).In conclusion,our findings showed that the CYP2B6*9(G516T)polymorphism is associated with B-CLL susceptibility among Egyptian patients.This variant greatly affected the clinical outcome and can serve as a good therapeutic marker in predicting response to cyclophosphamide treatment.

黄酮类化合物对细胞色素P450 CYP1A2的抑制作用及其构效关系研究

利用本实验室已建立的体外肝微粒体模型,测定36个黄酮类单体化合物对人细胞色素P450 CYP1A2的抑制活性,并使用三维定量构效关系方法研究化合物的分子结构参数与其抑制活性之间的关系。CoMSIA模型证实黄酮类化合物的结构参数与其CYP1A2抑制活性存在明显的相关性(模型的相关系数R2为0.948),且有良好的预测能力(交叉验证相关系数q2为0.630),同时使用"留五法"证实模型的稳定性和可靠性。结果表明,相对于黄酮,α-萘黄酮的π-π共轭体系更有利于提高化合物的抑制活性。根据获得的模型的三维等势图,在α-萘黄酮基础上,6、3′、4′位引入带正电基团或是疏水基团,同时5位引入带负电基团,能有效改善化合物的CYP1A2抑制活性。

注射用丹参总酚酸(冻干)对人CYP450酶和P-糖蛋白体外抑制作用及对大鼠CYP1A2和CYP3A体内诱导作用(英文)

目的探讨注射用丹参总酚酸(冻干)(SLI)对人CYP450酶和P-糖蛋白体外抑制作用以及对大鼠CYP1A2和CYP3A体内诱导作用。方法①应用P450-GloTMCYP450检测试剂盒,通过化学发光法测定SLI和经典抑制剂对细胞色素P4501A2(CYP1A2),CYP2D6,CYP3A4,CYP2C19和CYP2C9的IC50值,通过比较SLI和经典抑制剂对相应细胞色素P450亚型的IC50值来判断SLI对人CYP450酶的体外抑制作用。②Wistar大鼠分别iv给予SLI 3,10和30 mg·kg-1和诱导剂苯巴比妥钠20 mg·kg-1,采用探针底物法,通过比较代谢产物的生成速率来评价SLI对大鼠CYP1A2和CYP3A的诱导作用。③应用ATP酶检测试剂盒,通过化学发光法测定ATP酶活性来评价SLI是否为P-gp的底物或抑制剂。结果①CYP1A2,CYP2C9,CYP2C19,CYP2D6和CYP3A4抑制剂的IC50与SLI对其的IC50进行比较(CYP1A2:0.12μmol·L-1vs 840μmol·L-1;CYP2C9:3.362μmol·L-1vs 704μmol·L-1;CYP2C19:3.236μmol·L-1vs 306μmol·L-1;CYP2D6:0.117μmol·L-1vs 2660μmol·L-1;CYP3A4:0.078μmol·L-1vs 1780μmol·L-1)。②与空白对照组(86.4±6.3)nmol·g-1.min-1相比,SLI 3,10和30 mg·kg-1组CYP1A2活性分别为83.4±6.6,82.5±4.0和(83.4±6.6)nmol·g-1.min-1。与空白对照组(16.1±0.9)nmol·g-1.min-1比较,SLI 3,10和30 mg·kg-1组CYP3A活性分别为15.7±0.6,15.9±0.7和(15.9±1.0)nmol·g-1.min-1,无显著性差异。③以临床血药浓度为依据设计的一系列浓度的SLI 0.0002,0.0006,0.002,0.006,0.017,0.052,0.156和0.468 g.L-1的ATP酶活性分别与空白对照组进行比较(5.8,5.3,5.8,5.5,5.8,5.2,,5.8,5.3,vs 5.75μmol·g-1.min-1),无显著性差异。结论SLI临床给药剂量既不能体外抑制人CYP1A2,CYP2D6,CYP3A4,CYP2C19和CYP2C9酶活性,也不能诱导大鼠CYP1A2和CYP3A,同时也不是P-gp的体外抑制剂或底物。

石膏水煎液对肝微粒体细胞色素P450酶系中CYP1A2和CYP2E1的影响

目的:研究石膏水煎液对肝微粒体细胞色素P450酶CYP1A2和CYP2E1活性的影响,指导临床合理用药。方法:采用双抗体夹心酶联免疫吸附试验(ELISA)对肝脏细胞色素P450酶CYP1A2和CYP2E1进行了初步研究。结果:与空白对照组比较,石膏水煎液对大鼠肝脏中的CYP1A2含量有降低的趋势,对CYP2E1的含量没有显著影响。结论:石膏对大鼠肝微粒体CYP1A2活性有抑制作用,临床上当与经过CYP1A2代谢的药物合用时应适当调整药量。

O-去甲基文拉法辛对大鼠肝微粒体细胞色素P450酶亚型CYP1A2、CYP2C9、CYP2C19活性的影响

目的研究O-去甲基文拉法辛(ODV)对大鼠肝微粒体内细胞色素P450酶CYP1A2、CYP2C9、CYP2C19活性的影响。方法以生理盐水为对照,大鼠每日灌胃给予22.90 mg/kg的O-去甲基文拉法辛琥珀酸盐水合物,连续7 d,然后测定其肝微体CYP1A2、CYP2C9、CYP2C19的活性。结果与生理盐水对照组比较,ODV组CYP1A2、CYP2C9、CYP2C19活性无变化(P>0.05)。结论 ODV对大鼠CYP1A2、CYP2C9、CYP2C19活性无影响。

褪黑素对大鼠肝微粒体细胞色素P450含量及CYP1A2、CYP2C19活性的影响

目的观察褪黑素对大鼠肝微粒体内细胞色素P450(CYP450)含量及CYP1A2、CYP2C19活性的影响。方法生理盐水为对照,大鼠灌胃0.54 mg.kg-1.d-1的褪黑素,连续7 d,然后测定其肝微体中CYP450含量及CYP1A2、CYP2C19活性。结果与对照组比较,褪黑素组CYP450含量和CYP1A2、CYP2C19活性无变化(P>0.05)。结论褪黑素对CYP450含量和CYP1A2、CYP2C19活性无影响。

Cytochrome P450 2E1 genetic polymorphism and gastric cancer in Changle,Fujian Province

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.

Hepatoprotective effects of S-adenosyl-L-methionine against alcohol-and cytochrome P450 2E1-induced liver injury

S-adenosyl-L-methionine (SAM) acts as a methyl donor for methylation reactions and participates in the synthesis of glutathione. SAM is also a key metabolite that regulates hepatocyte growth, differentiation and death. Hepatic SAM levels are decreased in animal models of alcohol liver injury and in patients with alcohol liver disease or viral cirrhosis. This review describes the protection by SAM against alcohol and cytochrome P450 2E1-dependent cytotoxicity both in vitro and in vivo and evaluates mechanisms for this protection.

Cardioprotection of Shenfu preparata on cardiac myocytes through cytochrome P450 2J3

To evaluate whether Shenfu injection （SFI） protects against cardiac myocyte injury induced by Fupian injection （FPI） in vitro. METHODS： H9c2 cells were separately treated with FPI, Renshen injection （RSI） and SFI. Cell viability, lactate dehydrogenase （LDH） release, spontaneous beating rate of primative cardical cells, caspase-3/7 activity, cell apoptosis, and cytochrome P450 2J3 （CYP2J3） mRNA expression were analyzed. RESULTS： The viability of H9c2 cells treated with SFI （37 and 75 mg/mL） was significantly higher than that of H9c2 cells treated with FPI （25 and 50 mg/mL） （P〈0.05, P〈0.01, respectively）. LDH activity of H9c2 cells treated with SFI （75 mg/mL） was significantly decreased （P〈0.01） compared with that of H9c2 cells treated with FPI （50 mg/mL）. SFI （150 mg/mL） significantly attenuated FPI （100 mg/mL）-induced spontaneous beating rate decrease in primary myocardial cells after 4-hour treatment. Compared with FPI （12 and 25 mg/mL）, SFI （18 and 37 mg/mL） treatment could effectively reverse the change of caspase-3/7 activity （P〈0.01 and P〈0.01, respectively）. Compared with FPI （6 and 25 mg/mL）, apoptotic cells decreased significantly （P〈0.05, P〈0.01, respectively） when H9c2 cells were incubated with SFI （9 and 37 mg/mL）. The expression of CYP2J3 mRNA was down-regulated by FPI, while RSI and SFI could up-regulate the expression of CYP2J3 （P〈0.01）, which suggested the potential mechanism of protection of RSI against cardiac myocyte damage induced by FPI treatment. CONCLUSION： These observations indicate that SFI has the potential to exert cardioprotective effects against FPI toxicity. The effect was possibly correlated with the activation of CYP2J3.

Protective effect of tea polyphenols against paracetamol-induced hepatotoxicity in mice is significanly correlated with cytochrome P450 suppression

AIM:To investigate the hepatoprotective activity of tea polyphenols(TP)and its relation with cytochrome P450(CYP450)expression in mice. METHODS:Hepatic CYP450 and CYPb5 levels were measured by UV-spectrophotometry in mice 2 d after intraperitoneal TP(25,50 and 100 mg/kg per day). Then the mice were intragastricly pre-treated with TP (100,200 and 400 mg/kg per day)for six days before paracetamol(1000 mg/kg)was given.Their acute mortality was compared with that of control mice. The mice were pre-treated with TP(100,200,and 400 mg/kg per day)for five days before paracetamol (500 mg/kg)was given.Hepatic CYP2E1 and CYP1A2 protein and mRNA expression levels were evaluated by Western blotting,immunohistochemical staining and transcriptase-polymerase chain reaction. RESULTS:The hepatic CYP450 and CYPb5 levels in mice of TP-treated groups(100,200 and 400 mg/kg per day)were decreased in a dose-dependent manner compared with those in the negative control mice.TP significantly attenuated the paracetamol-induced hepatic injury and dramatically reduced the mortality of paracetamol-treated mice.Furthermore,TP reduced CYP2E1 and CYP1A2 expression at both protein and mRNA levels in a dose-dependent manner.

Establishment of a transgenic cell line stably expressing human cytochrome P450 2C18 and identification of a CYP2C18 clone with exon 5 missing

AIM: The human cytochrome P-450 2C18(CYP2C18) hasbeen characterized. However, the protein has not beenpurified from liver and very little is known regarding thespecific substrate of CYP2C18. In order to study its enzymaticactivity for drug metabolism, the CYP2C18cDNA was clonedand a stable CHL cell line expressing recombinant CYP 2C18was established.METHODS: The human CYP2C18cDNA was amplified withreverse transcription-polymerase chain reaction (RT-PCR)from total RNAs extracted from human liver and cloned intopGEM-T vector. The cDNA segment was identified by DNAsequencing and subcloned into a mammalian expressionvector pREP9. A transgenic cell line was established bytransfecting the recombinant plasmid of pREPg-CYP2C18toChinese hamster lung (CHL) cell. The enzyme activity ofCYP2C18 catalyzing oxidation of tolbutamide tohydroxytolbutamide in postmitochondrial supernant(Sg)fraction of the cell was determined by high performanceliquid chromatography(HPLC).RESULTS: The amino acid sequence predicted from thecloned cDNA segment was identical to that of reported byRomkes et al(GenBank accession number: M61856,J05326).The S9 fraction of the established cell line metabolizestolbutamide to hydroxytolbutamide. Tolbutamide hydroxylaseactivity was found to be 0.509±0.052 μmol.min-1.g-1 S9protein or 8.82±0.90 mol.min-1.mol-1 CYP, but wasundetectable in parental CHL cell. In addition, we haveidentified a CYP2C18cDNA clone with exon 5 missing.CONCLUSION: The cDNA of human CYP2C18 wassuccessfully cloned and a cell line, CHL-CYP2C18, efficientlyexpressing the protein of CYP2C18, was established. Aspliced variant of CYP2C18 with exon 5 missing was identifiedin the cloning process.

Cytochrome p450 2E1 polymorphisms and the risk of gastric cardia cancer

AIM: Genetic polymorphisms of drug-metabolizing enzymes have recently been shown to affect susceptibility to chemical carcinogenesis. Cytochrome P450 2E1 (CYP2E1)enzyme catalyzes the metabolism of many procarcinogens,such as N-nitrosamines and related compounds. The gene coding for this enzyme is polymorphic and thus may play a role in gastric cardia cancer (GCC) etiology. In this hospital-based case-control study, we evaluate the relationship between genetic polymorphisms of CYP2E1and the risk of GCC.METHODS: The study subjects comprised 159 histologically confirmed GCC cases identified via hospital cancer registry and surgical records at five hospitals in Fuzhou, Fujian Province, China, between April and November 2001.Controls were 192 patients admitted to the same hospitals for nonmalignant conditions. The genotypes of CYP2E1were detected by a PCR-based RFLP assay. The odds ratios were estimated by logistic regression analyses and were adjusted for potential confounding factors.RESULTS: The distribution of three genotypes of CYP2E1in GCC cases and controls was significantly different (X2 = 16.04, P＜0.01). The frequency of the CYP2E1 (c1/c1)genotype in GCC cases and controls was 60.4% and 40.1%,respectively. The CYP2E1 (c1/c1) genotype was associated with an increased risk for GCC (the adjusted (OR) was 2.37, 95% confidence interval (CI): 1.52-3.70). Subjects who carried the CYP2E 1 (c1/c1) genotype and were habitual smokers were at a significantly higher risk of developing GCC (OR = 4.68, 95%CI: 2.19-10.04) compared with those who had the CYP2E1 (c1/c2or c2/c2') genotype and did not smoke.CONCLUSION: These results suggest that the CYP2E 1genotype may influence individual susceptibility to development of GCC, and that the risk increases significantly in smokers.

Cytochrome P450 2E1 RsaI/PstI and DraI Polymorphisms Are Risk Factors for Lung Cancer in Mongolian and Han Population in Inner Mongolia

Objective： To explore the relationship between cytochrome P450 2E1 （CYP2E1） RsaI/PstI and DraI polymorphism and lung cancer susceptibility in Mongolian and Han population in Inner Mongolia of China. Methods： CYP2E1 RsaI/PstI and DraI polymorphisms were detected by polymerase chain reaction-restriction fragment length polymorphism in 64 lung cancer patients, 150 healthy Mongolian and 150 healthy Han individuals. The distribution of genotype and allele frequencies of CYP2E1 RsaI/PstI and DraI polymorphisms were studied. Results： The risk of lung cancer was increased in individuals with CYP2E1 （cl/cl） and CYP2E1 （DD） with OR values of 2.431 （95%CI=1.082-5.460） and 2.778 （95%CI=1.358-5.683） respectively （P0.05）. When CYP2E1 RsaI/PstI and DraI polymorphisms were combined, the risk of lung cancer was reduced in individuals with CYP2E1 （cl/c2＋c2/c2 and DD＋CC） with OR values of 0.233 （95%CI=0.088-0.615, P0.05）. In smokers, the susceptibility to lung cancer was higher in the individuals with CYP2E1 （c1/c1） and CYP2E1 （DD） than in the individuals with c2 and C allele （P0.05, OR=2.643 and 4.308 respectively）. There was no significant difference in distribution of CYP2E1 genotype frequency between healthy Mongolian, Han population and lung cancer patients, healthy controls in Inner Mongolia. Conclusion： CYP2E1 （c1/c1） and CYP2E1 （DD） are predisposing factors of lung cancer in population in Inner Mongolia. CYP2E1 （c2﹢C） co-mutation may decrease the risk of lung cancer. Smoking exerts synergetic effect with CYP2E1 （c1/c1） and CYP2E1 （DD） on the occurrence of lung cancer.

柴胡水提液对大鼠肝CYP450酶含量及其亚型CYP3A、CYP2E1和CYP1A2活性的影响

目的:研究柴胡水提物对大鼠细胞色素CYP450酶含量及对亚型CYP3A、CYP2E1和CYP1A2活性的影响。方法:大鼠灌胃给予柴胡水提液7d后取肝脏称重并制备肝微粒体,紫外分光光度法测定肝微粒体细胞色素b5(Cytb5)、P450的含量及CYP3A的活性,高效液相法测定CYP2E1和CYP1A2的活性。结果:与空白对照组比较,柴胡水提液组大鼠肝指数无显著变化,CYP450含量减少但统计学意义(P>0.05),CYP1A2活性极显著降低(P<0.01),CYP2E1活性明显降低(P<0.05)。结论:柴胡水提液降低大鼠肝脏CYP450酶含量并抑制CYP2E1和CYP1A2的活性,由于抑制CYP450酶活性,减少对其他药代谢,提示若柴胡水提液与经CYP2E1和CYP1A2代谢的药物同用,有可能会影响这些药物的临床疗效,临床用药时应慎重考虑。

In vitro and in vivo cytochrome P450 3A enzyme inhibition by Aframomum melengueta and Dennettia tripetala extracts

Objective: To evaluate the in vitro and in vivo inhibitory effects of two commonly used herbs, Aframomum melengueta(A. melengueta) and Dennettia tripetala(D. tripetala) on CYP 3A enzymes. Methods: In vitro inhibition of the enzymes were assessed with microsomes extracted from female albino rats using erythromycin-N-demethylation assay(EMND) method while their in vivo effects were measured by estimating simvastatin plasma concentrations in rats. Pharmacokinetic parameters were determined using non-compartmental anaysis as implemented in Win Nonlin pharmacokinetic program. Results: EMND assay with intestinal microsomes indicated that aqueous extracts of D. tripetala and A. melengueta significantly(P < 0.05) inhibited intestinal CYP 3A activity at both 50 μg and 100 μg concentrations. Petroleum ether extract of D. tripetala and ethanol extracts of A. melengueta inhibited intestinal CYP3 A activity at 100 μg but not at 50 μg concentrations. All the extracts showed an in vitrodose dependent CYP 3A inhibition with liver microsomes. In vivo analysis showed that pretreatment with the extracts enhanced systemic absorption of simvastatin with reductions in metabolizing enzymes activity as indicated in significant increases in maximal concentration, area under curve, area under moment curve and mean resident time of simvastatin(P < 0.05). Conclusions: Herbal preparations containing these plants' extracts should be used with caution especially in patients on CYP450 3A substrate medications.

Cytochrome P450 family 17 subfamily A member 1 mutation causes severe pseudohermaphroditism: A case report

BACKGROUND 17α-Hydroxylase deficiency(17-OHD)is a rare form of congenital adrenal hyperplasia,characterized by hypertension,hypokalemia,and gonadal dysplasia.However,due to the lack of a comprehensive understanding of this disease,it is prone to misdiagnosis and missed diagnosis,and there is no complete cure.CASE SUMMARY We report a female patient with 17-OHD.The patient was admitted to the Department of Neurology of our hospital due to limb weakness.During treatment,it was found that the patient’s condition was difficult to correct except for hypokalemia,and her blood pressure was difficult to control with various antihypertensive drugs.She was then transferred to our department for further treatment.On physical examination,the patient's gonadal development was found to be abnormal,and chromosome analysis demonstrated karyotype 46,XY.Considering the possibility of 17-OHD,the cytochrome P450 family 17 subfamily A member 1(CYP17A1)test was performed to confirm the diagnosis.CONCLUSION The clinical manifestations of 17-OHD are complex.Hormone determination,imaging examination,chromosome determination and CYP17A1 gene test are helpful for early diagnosis.

Cytotoxicity of acrylamide and its epoxide glycidamide in CHO cells expressing human cytochrome P450 2E1

Objective： To investigate whether CYP2E1 is responsible for the acrylamide metabolic activation in FIp-In CHO cell system. Methods： CYP2E1 cDNA was subcloned from the human liver full-length cDNA library and subsequently transfected into the FIp-In CHO cells to generate the stable transfectant of CYP2E1. The CYP2E1 mRNA expression was determined by RT-PCR. Acrylamide and its epoxide glycidamide induced cytotoxicity and cell cycle arrest in G2/M were conducted using MTS assay and flow cytometry, respectively. Results： In the CHO cell stably expressing CYP2E1 （CHO-2E1）, a -1.5 kb size of band was detected from the mRNA in the cells while no corresponding band in the CHO-vector cells, which indicated that CYP2E1 was successfully transfected in the CHO cells. Compared with the CHO-vector cells, acrylamide showed a concentration dependent loss of viability in the CHO-2E1 cells but no significant change of G2/M arrest was found. As expected, glycidamide induced similar profile of cytotoxicity in both of the cells, and G2/M arrest presented a concentration-dependent increased in the CHO-2E1 cells. Conclusion： The result suggested that CYP2E1 might be responsible for the acrylamide metabolism, and its metabolite glycidamide was a direct cytotoxic and genotoxic agent. It should be further considered whether acrylamide-induced toxicity is through its epoxide glycidamide in the presence of CYP2E1.

Identification and analysis of a processed cytochrome P450 pseudogene of the disease vector Aedes aegypti

Objective: To clone cytochrome P450 from Aedes aegypti(Ae. aegypti) and determine the characteristics using bioinformatics tools. Methods: Cytochrome P450 of Ae. aegypti was amplified using polymerase chain reaction, cloned and sequenced. Evolutionary relationship of the sequence was inferred and bioinformatics tools were used to predict subcellular localisation, signal peptide, transmembrane helix, phosphorylation, O-glycosylation, secondary and tertiary structures of the deduced protein. Results: Polymerase chain reaction rather amplified a cytochrome P450 pseudogene which was named CYP4H44P(Gen Bank accession number KF779932). The pseudogene has 1537 nucleotides and an open reading frame of 335 amino acids containing cytochrome P450 motifs except the Wxxx R motif. It is highly homologous to CYP4H28 and CYP4H28v2. Phylogenetic analysis and evolutionary divergence showed strong clustering with CYP4H28 alleles and least divergence from the alleles respectively. The deduced protein was predicted to be found in the cytoplasm and likely to be phosphorylated but devoid of signal peptide, transmembrane helix and O-glycosylated sites. The secondary and tertiary structures were also generated. Conclusions: A cytochrome P450 pseudogene, CYP4H44 P was cloned from Ae. aegypti. The pseudogene is homologous with CYP4H28 alleles and seems to have recently diverged from this group. Isolating this pseudogene is an important step for evaluating its biological role in the mosquito and for the evolutionary analysis of Ae. aegypti CYPs.

Expression of cytochrome P450 2A13 in human non-small cell lung cancer and its clinical significance

Lung cancer is one of the most important causes of cancer-related mortality worldwide. Human cytochrome P450 2A13 enzyme （CYP2A13） is predominantly expressed in the respiratory tract and could catalyze various carcinogens. In this study, we quantified CYP2A13 expression in non-small cell lung cancer （NSCLC） tissues and examined the relation between CYP2A13 and clinicopathologic factors. Thirty-five paired lung cancer and normal tissues were studied for the expression of the CYP2A13 gene by using real-time PCR and Western blot- ting assays. We also investigated the relationship between CYP2A13 expression and clinicopathologic factors such as age, gender, histology and lymph node status in tumor tissues. SPSS （17.0） statistical software was applied for data analysis. The real-time PCR results showed that there was no significant difference in the CYP2A13 mRNA transcript levels between tumor and paired normal tissues in the 35 samples and in 12 paired squamous cell car- cinomas. In adenocarcinoma, the expression of CYP2A13 mRNA in tumor tissues was 12.5% of that in adjacent tissues （P 〈 0.05） and it was not associated with age, gender, histology and lymph node status of the patients. The amounts of CYP2A13 proteins detected by Western blotting assays correlated well with those of the correspond- ing mRNAs. In conclusion, the expression of CYP2A13 was downregulated in lung adenocarcinoma. CYP2A13 may be involved in the development and progression of lung adenocarcinoma.

Cytochrome P450 2E1 high activity polymorphism in alcohol abuse and end-organ disease

AIM: To investigate a possible role for a recently identified polymorphism in the gene of cytochrome P450 2E1, the presence of which is associated with high activity of the enzyme. METHODS: Two hundred and thirty-nine alcohol consumers, ICD 10.1/.2 (ALC), and 208 normal controls were studied. PCR amplification of the CYP2E1 gene region was performed to assess polymorphic variation. Fisher's exact test was used to assess the data.RESULTS: Twelve normal controls (5.8%) possessed the insertion. Five ALC (2.1%) had the insertion; of these 2 of 144 with,alcohol induced chronic pancreatitis, none of 28 with alcoholic liver disease and 3 of 67 without endorgan disease had the polymorphism. A significantly Lower frequency of subjects possessed the insertion than normal controls [P = 0.049 (genotype analysis P = 0.03)]. To further assess, if there was a relationship to alcohol problems per se or end-organ disease, we compared patients with alcohol induced end-organ disease vs alcoholic controls without end-organ disease vs normal controls which again showed a significant difference [P = 0.045 (genotype analysis,P = 0.011)], further sub-group analysis did not identify which group(s) accounted for these differences.CONCLUSION: We have shown the frequencies of this high-activity polymorphism in alcohol related patient groups for the first time. The frequency is significantly less in alcoholics than normal controls, as with high activity polymorphisms of alcohol dehydrogenase. The biological significance, and whether the relevance is solely for alcoholism or is there a relationship to end-organ disease,would benefit from the assessment in the populations with a greater frequency of this polymorphism.