• Toxicological Research
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• v.27 no.1
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• pp.25-29
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• 2011

The cytochrome P450 (P450, CYP) are the superfamily of heme-containing monooxygenase enzymes, found throughout all nature including mammals, plants, and microorganisms. Mammalian P450 enzymes are involved in oxidative metabolism of a wide range of endo- and exogenous chemicals. Especially P450s involved in drug metabolisms are important for drug efficacy and polymorphisms of P450s in individuals reflect differences of drug responses between people. To study the functional differences of CYP2A6, CYP2D6, and CYP4A11 variants, we cloned the four CYP2A6, three CYP2D6, and three CYP4A11 variants, which were found in Korean populations, in mammalian expression vector pcDNA by PCR and examined their expressions in COS-7 mammalian cells using immunoblots using P450 specific polyclonal antibodies. Three of four CYP2A6, two of three CYP4A11, and two of three CYP2D6 variants showed expressions in COS-7 cells but the relative levels of expressions are remarkably different in those of each variants. Our findings may help to study and explain the differences between functions of CYP variants and drug responses in Korean populations.

• Biomolecules & Therapeutics
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• v.21 no.6
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• pp.487-492
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• 2013

Cytochrome P450 4A11 (CYP4A11) is a fatty acid hydroxylase enzyme expressed in human liver. It catalyzes not only the hydroxylation of saturated and unsaturated fatty acids, but the conversion of arachidonic acid to 20-hydroxyeicosatetraenoic acid (20-HETE), a regulator of blood pressure. In this study, we performed a directed evolution analysis of CYP4A11 using the luminogenic assay system. A random mutant library of CYP4A11, in which mutations were made throughout the entire coding region, was screened with luciferase activity to detect the demethylation of luciferin-4A (2-[6-methoxyquinolin-2-yl]-4,5-dihydrothiazole-4-carboxylic acid) of CYP4A11 mutants in Escherichia coli. Consecutive rounds of random mutagenesis and screening yielded three improved CYP4A11 mutants, CP2600 (A24T/T263A), CP2601 (T263A), and CP2616 (A24T/T263A/V430E) with ~3-fold increase in whole cells and >10-fold increase in purified proteins on the luminescence assay. However, the steady state kinetic analysis for lauric acid hydroxylation showed the significant reductions in enzymatic activities in all three mutants. A mutant, CP2600, showed a 51% decrease in catalytic efficiency ($k_{cat}/K_m$) for lauric acid hydroxylation mainly due to an increase in $K_m$. CP2601 and CP2616 showed much greater reductions (>75%) in the catalytic efficiency due to both a decrease in $k_{cat}$ and an increase in Km. These decreased catalytic activities of CP2601 and CP2616 can be partially attributed to the changes in substrate affinities. These results suggest that the enzymatic activities of CYP4A11 mutants selected from directed evolution using a luminogenic P450 substrate may not demonstrate a direct correlation with the hydroxylation activities of lauric acid.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.6
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• pp.2647-2653
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• 2012

Involvement of cytochrome P450 genes (CYPs) in breast cancer (BCa) may differ between populations, with expression patterns affected by tumorigenesis. This may have an important role in the metabolism of anticancer drugs and in the progression of cancer. The aim of this study was to determine the mRNA expression patterns of four cytochrome P450 genes (CYP2W1, 3A5, 4F11 and 8A1) in Mexican women with breast cancer. Real-time PCR analyses were conducted on 32 sets of human breast tumors and adjacent non-tumor tissues, as well as 20 normal breast tissues. Expression levels were tested for association with clinical and pathological data of patients. We found higher gene expression of CYP2W1, CYP3A5, CYP4F11 in BCa than in adjacent tissues and only low in normal mammary glands in our Mexican population while CYP8A1 was only expressed in BCa and adjacent tissues. We found that Ki67 protein expression was associated with clinicopathological features as well as with CYP2W1, CYP4F11 and CYP8A1 but not with CYP3A5. The results indicated that breast cancer tissues may be better able to metabolize carcinogens and other xenobiotics to active species than normal or adjacent non-tumor tissues.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.3
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• pp.837-846
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• 2012

Breast cancer (BCa) is the leading type of cancer in Mexican women. Genetic factors, such as single nucleotide polymorphisms (SNP) of P450 system, have been reported in BCa. In this report, and for the first time in the literature, we analyzed the rs3735684 (7021 G>A), rs11553651 (15016 G>T) and rs56195291 (60020 C>G) polymorphisms in the CYP2W1, 4F11 and 8A1 genes in patients with BCa and in healthy Mexican women to identify a potential association between these polymorphisms and BCa risk. Patients and controls were used for polymorphism analysis using an allelic discrimination assay with TaqMan probes and confirmed by DNA sequencing. Links with clinic-pathological characteristics were also analyzed. Statistical analysis was performed using the standard ${\chi}^2$ or Fisher exact test statistic. No significant differences were observed in the distributions of CYP2W1 (OR 8.6, 95%CI 0.43-172.5 P>0.05; OR 2.0, 95%CI 0.76-5.4, P>0.05) and CYP4F11 (OR 0.3, 95%CI 0.01-8.4 P>0.05) genotypes between the patients and controls. Only the CYP8A1 CC genotype was detected in patients with BCa and the controls. All polymorphism frequencies were in Hardy-Weinberg Equilibrium (HWE) in the controls (P>0.05). We found a significant association between BCa risk and smoking, use of oral contraceptives or hormonal replacement therapy (HRT), obesity, hyperglycemia, chronic diseases, family history of cancer and menopausal status in the population studied (P<0.05). Tobacco, oral contraceptive or HRT, chronic diseases and obesity or overweight were strongly associated with almost eight, thirty-five, nine and five-fold increased risk for BCa. Tobaco, obesity and hyperglycemia significantly increased the risk of BCa in the patients carrying variant genotypes of CYP2W1 (P<0.05). These results indicate that the CYP2W1 rs3735684, CYP4F11 rs11553651 and CYP8A1 rs56195291 SNPs are not a key risk factor for BCa in Mexican women. This study did not detect an association between the CYP2W1, 4F11 and 8A1 genes polymorphisms and BCa risk in a Mexican population. However, some clinico-pathological risk factors interact with CYP2W1 genotypes and modifies susceptibility to BCa.

• Korean Journal of Clinical Laboratory Science
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• v.54 no.4
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• pp.316-324
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• 2022

Polycystic ovary syndrome (PCOS) is a complex endocrinopathy in women of reproductive age. The genetics of PCOS is heterogeneous with the involvement of number of genes in the steroid synthesis pathway. The CYP11B2 encodes aldosterone synthase and the genetic variants might increase aldosterone secretion in PCOS cases. CYP1A1 is known to enhance the intraovarian catechol estrogen production and thus the propensity for PCOS. The present case-control study analyzed a total of 619 females for CYP11B2 (rs1799998) and CYP1A1 (rs4646903) polymorphisms. Obesity was examined according to body mass index (BMI) and waist hip ratio (WHR) categorization. Biochemical (lipid profile) analysis was performed in PCOS females. BMI (P=0.0001) and WHR (P=0.0001) revealed a statistically significant difference between PCOS cases and controls. The overall levels of triglycerides were higher in PCOS females. The genotype frequency distribution of CYP11B2 (rs1799998) polymorphism revealed statistically significant difference between PCOS cases and controls (P=0.017). However, CYP1A1 (rs4646903) polymorphism did not showed any association with PCOS. The present case-control association analysis is first from our region for CYP1A1 and CYP11B2 polymorphisms and is suggestive of genetic predisposition of steroidogenic genes among PCOS patients in the North-Indian Punjabi females.

• Archives of Pharmacal Research
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• v.27 no.7
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• pp.693-712
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• 2004

The rats with protein-calorie malnutrition (PCM, 5％ casein diet for a period of 4-week) were reported to exhibit 60 and 80％ suppression in the hepatic microsomal cytochrome P450 (CYP) 1 A2 and CYP2C11 levels, respectively, and 40-50％ decreases in CYP2E1 and CYP3A 1/2 levels compared to control (23％ casein diet for a period of 4-week) based on Western blot analysis. In addition, Northern blot analysis showed that CYP1 A2, CYP2E1, CYP2C11, and CYP3A1/2 mRNAs decreased in the state of PCM as well. Hence, pharmacokinetic changes of the drugs in rats with PCM [especially the area under the plasma concentration-time curve from time zero to time infinity (AUC) changes of metabolite(s)] reported from literatures were tried to explain in terms of CYP isozyme changes in the rats. Otherwise, the time-averaged nonrenal clearance ($CL_{NR}$) of parent drug was compared. Pharmacokinetic changes of the drugs in other types of malnutritional state, such as kwashiorkor and marasmus, in both human and animal models were also compared. The drugs reviewed are as follows： diuretics, antibiotics, anticancer agents, antiepileptics, antiarrythmics, analgesics, xanthines, antimalarials, and miscellaneous.

• Mass Spectrometry Letters
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• v.11 no.4
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• pp.113-117
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• 2020

Cytochrome P450 2J2 (CYP2J2) is a member of the cytochrome P450 superfamily, and is known to be arachidonic acid epoxygenase that mediates the formation of four bioactive regioisomers of epoxyeicosatrienoic acids (EETs). CYP2J2 is also involved in the metabolism of drugs such as albendazole, astemizole, danazol, ebastine, and terfenadine. CYP2J2 is highly expressed in the heart and cancer tissues. In this study, the inhibitory potential of ten natural products against CYP2J2 activity was evaluated using human liver microsomes and tandem mass spectrometry. Among them, bilobetin, which is a kind of biflavonoid, exhibits a strong inhibitory effect against the CYP2J2-mediated astemizole O-demethylation (IC50 = 0.73 μM) and terfenadine hydroxylation (IC50 = 0.89 μM). This result suggests that bilobetin can be used as strong CYP2J2 inhibitor in drug metabolism study.

• Mycobiology
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• v.47 no.3
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• pp.301-307
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• 2019

The $11{\alpha}$-hydroxylation of $16{\alpha}$, 17-epoxyprogesterone (EP) catalyzed by Rhizopus nigricans is crucial for the steroid industry. However, lower conversion rate of the biohydroxylation restricts its potential industrial application. The $11{\alpha}$-steroid hydroxylase CYP509C12 from R. oryzae were reported to play a crucial role in the $11{\alpha}$-hydroxylation in recombinant fission yeast. In the present study, the CYP509C12 of R. oryzae (RoCYP) was introduced into R. nigricans using the liposome-mediated mycelial transformation. Heterologous expression of RoCYP resulted in increased fungal growth and improved intracellular reactive oxygen species content in R. nigricans. The $H_2O_2$ levels in RoCYP transformants were approximately 2-folder that of the R. nigricans wild type (RnWT) strain, with the superoxide dismutase activities increased approximately 45% and catalase activities decreased approximately 68%. Furthermore, the $11{\alpha}$-hydroxylation rates of EP in RoCYP transformants (C4, C6 and C9) were 39.7%, 38.3% and 38.7%, which were 12.1%, 8.2% and 9.4% higher than the rate of the RnWT strain, respectively. This paper investigated the effect of heterologous expression of RoCYP in R. nigricans, providing an effective genetic method to construct the engineered strains for steroid industry.

• The Korean Journal of Physiology and Pharmacology
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• v.5 no.5
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• pp.407-412
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• 2001

Many drugs are primarily metabolized by the cytochrome P450s (CYPs). Drug metabolites would be important allergens for adverse drug reactions such as drug eruptions. Skin tests with a suspected drug have conducted to identify causative drugs of drug eruptions, with vehicles such as white petrolatum, DMSO, ethanol. This study will compare the expression of rat CYP isozyme mRNAs between the skin and the liver, with examining an effect of the vehicles on the cutaneous CYPs using semi-quantitative RT-PCR. Thirty-two Sprague-Dawley rats between the ages of six and eight weeks were divided as four groups. One group was used to compare the constitutive mRNA expression between skin and liver, while the others were to examine the effects of three vehicles. The ratios of expression of CYP1A2, CYP2B1/2, CYP2E1, CYP3A1, and CYP4A1 were significantly higher in the liver than the skin. However, CYP1A1 and CYP2C11 were higher in the skin than liver. The effects of vehicles were quite different; white petrolatum significantly induced CYP1A1 (p=0.012) and CYP2C11 mRNAs, while ethanol inhibited CY P1A1 and CYP2B1/2. DMSO did not make any changes. The results suggest that rat skin can participate in drug metabolism with their own CYP isozymes. The effects of vehicles on the cutaneous CYP expression should not be ignored and may be applied for determination of an appropriate vehicle for certain drug(s).

• Clinical and Experimental Reproductive Medicine
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• v.31 no.4
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• pp.245-251
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• 2004

Objectives: To investigate the distribution and functional significance of $CYP11{\alpha}$ $(tttta)_n$ microsatellite polymorphism in Korean patients with polycystic ovary syndrome Materials and Methods: Analysis of $CYP11{\alpha}$ $(tttta)_n$ microsatellite polymorphism was carried out on DNA samples from 97 patients with polycystic ovary syndrome and 70 normal controls. Comparison were done between PCOS patients and controls concerning $CYP11{\alpha}$ $(tttta)_n$ microsatellite polymorphism genotype or allele frequencies. Results: The most frequent allele observed in the controls was an allele with six repeats (60.7%). Significant difference in the frequency of genotype (4R (-) genotype) having no copy of four-repeatallele were observed between PCOS patients and controls (66.0% vs 34.0%, p=0.038, OR=1.939). But no significant difference was observed in the serum levels of total testosterone or free testosterone between 4R (+) genotype and 4R (-) genotype among PCOS patients. However, hyperandrogenic PCOS patients with 4R (+) genotype showed a higher serum testosterone levels compared to controls (mean $\pm$ S.D: $0.49{\pm}0.21\;ng/ml$ vs $0.37{\pm}0.18\;ng/ml$, p=0.037). Conclusion: The alleleic distribution of $CYP11{\alpha}$ $(tttta)_n$ microsatellite polymorphism in Korean subjects were different from those reported in Caucasians. $CYP11{\alpha}$ $(tttta)_n$ microsatellite polymorphism was associated with polycystic ovary syndrome in the Korean population, and may play a role in the synthesis of androgens in patients with polycystic ovary syndrome.