The intake of weakly estrogenic isoflavonoids (phytoestrogens) is high in countries with a low incidence of estrogenrelated cancers, such as breast and prostate cancers. 1) Two ERs (a and b ) have been identified to date and the physiological responses of estrogens are known to be mediated within specific tissues by at least these two receptors.2,3) The ERs are a 3A member of the nuclear hormone receptor family and act as a ligand-activated nuclear transcription factor. 4)In a previous paper, we reported the results of systematic examination of the estrogenic activities of soy isoflavones (e.g. daidzin, genistin and glycitin) and their metabolites (e.g. daidzein, genistein, glycitein, equol, dihydrogenistein and dihydroglycitein) by enteric bacteria, 5) and the activities of several other isoflavone derivatives isolated from Pueralia lobata and P. thomsonii. 6)Usually, when soy foods are consumed, the soy isoflavones are metabolized into their aglycones and the related compounds by enteric bacteria. We have proved in in vitro experiments that the soy isoflavone glycosides are less estrogenic than the metabolites, i.e., they are activated by enteric bacteria. The metabolites produced by enteric bacteria are absorbed through the intestinal membranes and transported to the liver where they undergo re-metabolization by hepatic enzymes. To evaluate the bioactive compounds in soy products, investigation of the compounds which are actually absorbed within the body is necessary. 7,8) Herein, we describe the results of an investigation on the estrogenic activities of soy isoflavone metabolites isolated from human urine samples. Their effects on the estrogen dependent growth of MCF-7 cells, 9,10) on human ERs (hERs a and b )-dependent b-galactosidase induction, and their binding behavior to hERs were studied. We also examined the estrogenic activities of some synthetic isoflavone sulfates for the purpose of comparison. [2,4,6, H(N)]-17b-Estradiol (72 Ci/mmol) was purchased from Dai-Ichi Pure Chemicals Co. Ltd. RPMI 1640 medium (with or without phenol red), fetal bovine serum (FBS), trypsin/EDTA, Dulbecco's phosphate-bufferd saline (PBS), and kanamycin sulfate were purchased from Lifetech (Rockville, MD, U.S.A.). MATERIALS AND METHODS ChemicalsIsoflavone Metabolites Isoflavone metabolites examined in this work are shown in Fig. 1. M-1-9 were isolated from human urine samples collected for 12 h after feeding soy bean curds.11) Dihydrodaidzein and O-desmethylangolensin (O-DMA) were synthesized following the method described by Wahara et al.12) Genistein 4Ј-O-sulfate (S-1), 4Ј,7-di-Osulfate (S-2), daidzein 4Ј-O-sulfate (S-3), and 4Ј,7-di-O-sulfate (S-4) were synthesized following the method described by Peterson et al. 13)Cells MCF-7 cells were supplied by the Cell Resource Center for the Biomedical Research, Institute of Development, Aging and Cancer, Tohoku University.Growth of MCF-7 Cells MCF-7 cells were cultured in phenol red-free RPMI 1640 medium supplemented with 10% (v/v) FBS and kanamycin sulfate (100 mg/ml) in 25 cm...
Estrogens play important hormonal roles in all vertebrates. Animal estrogens are exclusively steroidal compounds, and the principal physiological estrogen in most species is 17b-estradiol. Many plants produce isoflavones that possess estrogenic activity in animals and are, thus, called phytoestrogens. Two estrogen receptors (ERs) have been identified to date 1,2) and the physiological responses to estrogen are known to be mediated within specific tissues by at least these two receptors. The ERs are a 3A member of the nuclear hormone receptor family and act as ligand-activated nuclear transcription factors. 3)Among the foods consumed by humans, soybeans contain the highest concentration of isoflavones. We have examined the estrogenic activity of these soy isoflavones (e.g., daidzin, genistin and glycitin) and their metabolites (e.g., daidzein, genistein, glycitein, equol, dihydrogenistein and dihydroglycitein) by enteric bacteria in the previous paper. 4) In this paper, we examined the estrogenic activities of several other isoflavone derivatives by (A) binding to human estrogen receptor (hER) a and b, and (B) effect on estrogen receptordependent transcriptional expression. 4) MATERIALS AND METHODS
Intragastric administration of rikkunshito stimulates gastrointestinal contractions in the interdigestive state through cholinergic neurons and 5-HT type 3 receptors. Moreover, rikkunshito increases plasma acylated ghrelin levels. Rikkunshito may alleviate gastrointestinal disorders through its prokinetic effects.
Background: Polymorphisms of the CYP2C9 (cytochrome P450, family 2, subfamily C, polypeptide 9) gene (CYP2C9*2, CYP2C9*3) and the VKORC1 (vitamin K epoxide reductase complex, subunit 1) gene (−1639G>A) greatly impact the maintenance dose for the drug warfarin. Prescreening patients for their genotypes before prescribing the drug facilitates a faster individualized determination of the proper maintenance dose, minimizing the risk for adverse reaction and reoccurrence of thromboembolic episodes. With current methodologies, therapy can be delayed by several hours to 1 day if genotyping is to determine the loading dose. A simpler and more rapid genotyping method is required. Methods: We developed a single-nucleotide polymorphism (SNP)-detection assay based on the SMart Amplification Process version 2 (SMAP 2) to analyze CYP2C9*2, CYP2C9*3, and VKORC1 −1639G>A polymorphisms. Blood from consenting participants was used directly in a closed-tube real-time assay without DNA purification to obtain results within 1 h after blood collection. Results: We analyzed 125 blood samples by both SMAP 2 and PCR-RFLP methods. The results showed perfect concordance. Conclusions: The results validate the accuracy of the SMAP 2 for determination of SNPs critical to personalized warfarin therapy. SMAP 2 offers speed, simplicity of sample preparation, the convenience of isothermal amplification, and assay-design flexibility, which are significant advantages over conventional genotyping technologies. In this example and other clinical scenarios in which genetic testing is required for immediate and better-informed therapeutic decisions, SMAP 2–based diagnostics have key advantages.
In the past decade, molecular-targeted drugs have been focused upon for the treatment of cancer. In 2002, gefitinib, an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor became available in Japan for the treatment of non-small cell lung cancer (NSCLC). Over 80% of selected patients, such as EGFR mutation-positive patients, respond to gefitinib treatment; however, most patients develop acquired resistance to gefitinib within a few years. Recently, many studies have been performed to determine precisely how to select patients who will respond to gefitinib, the best timing for its administration, and how to avoid the development of acquired resistance as well as adverse drug effects. This article reviews the use of gefitinib for the treatment of NSCLC from a pharmaceutical viewpoint.
Background: Pembrolizumab is currently the standard treatment for patients with advanced non-small cell lung cancer (NSCLC). However, the association between immune-related adverse events (irAEs) and peripheral blood cell counts remains unclear. We aimed at identifying peripheral blood cell counts that may predict the development of pembrolizumab-induced irAEs. Methods: We retrospectively analyzed data on consecutive patients with advanced NSCLC who received pembrolizumab monotherapy as first-line or later-line therapy at the National Cancer Center Hospital and Keio University Hospital. We used data between December 2015 and November 2018. The primary endpoint was the relationship between peripheral blood cell count data and early-onset irAEs during the 6-weeks study period. Receiver operating characteristic (ROC) curve and multivariable logistic regression analyses were performed. Results: In total, 92 patients were evaluated, of whom 45 (48.9%) had at least one irAE during the first 6-weeks after treatment initiation. The ROC curves revealed that the optimal cutoff of pretreatment absolute lymphocyte count (ALC), neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), and platelet-to-lymphocyte ratio (PLR) for onset of irAEs were 1459, 2.320, 1.538, and 165, respectively. Multivariable logistic regression analyses revealed that pretreatment ALC>1450 and LMR>1.6 were significantly associated with a reduced risk for onset of any irAEs, whereas pretreatment NLR>2.3 and PLR>165 were significantly associated with an increased risk. Conclusions: The findings suggest that considering the routine availability of blood cell count data before the initiation of treatment with pembrolizumab, it may be useful in identifying early-onset irAEs during the 6-weeks study period in clinical practice.
SUMMARYWhat is known and Objective: Polymorphisms in the gene encoding CYP4F2 may partly explain the variability in warfarin maintenance dose by altering the metabolism of vitamin K. To determine the genetic factors that cause large inter-patient variability in warfarin efficacy, we investigated the relationship between serum warfarin concentration and CYP4F2 V433M (1347C>T, rs2108622) polymorphism in Japanese subjects. Methods: Gene variations in VKORC1, CYP2C9 and CYP4F2 were analysed in 126 Japanese patients treated with warfarin. The daily dosage of warfarin, concentration of S-and R-warfarin in plasma, and prothrombin time international normalized ratio (PT-INR) was used as the pharmacokinetic and pharmacodynamic indices. Results and Discussion: The maintenance dose of warfarin was larger in the CYP4F2 1347 CT genotype group (3AE59 ± 1AE80 mg/day, P = 0AE027) than in the CYP4F2 CC genotype group (2AE88 ± 1AE00 mg/day). CYP4F2 1347C>T polymorphism significantly affected serum R-warfarin concentration when the VKORC1-1639 genotypes are AG and GG. What is new and Conclusion: Although a significant interpatient difference in warfarin maintenance dose was observed between the CYP4F2 CC and CT genotypes, serum S-warfarin concentration was not significantly different between them. An effect of CYP4F2 V433M polymorphism on warfarin maintenance dose was observed but was relatively small when compared to the effects of CYP2C9 and VKOR polymorphism. WHAT IS KNOWN AND OBJECTIVEWarfarin is the most widely prescribed anticoagulant for thromboembolic disorders. Because of its narrow therapeutic index and the large individual variability in the relationship between warfarin dosage and its anticoagulant effect, 1 careful adjustment of dosage based on prothrombin time expressed as the international normalized ratio (PT-INR) is essential. Clinically available warfarin is a racemic mixture of S-and R-warfarin, and the potency of S-warfarin is 3-to 5-fold higher than that of R-warfarin. 1,2 S-warfarin is predominantly metabolized to 7-hydroxywarfarin by polymorphic cytochrome P450 2C9 (CYP2C9), while R-warfarin is metabolized by multiple CYPs, including CYP1A2 and CYP3A4. 3,4 The activity of CYP2C9 is likely to have a significant influence on the anticoagulant effect of S-warfarin. Previous findings revealed that the gene variants CYP2C9*2 (Arg144Cys) and CYP2C9*3 (Ile359Arg) in the CYP2C9 gene are associated with lower therapeutic dosing of warfarin than the wild-type (CYP2C9*1) allele owing to the impaired metabolic capacity of their encoded CYPs. 2 The vitamin K oxide reductase complex subunit 1 (VKORC1), a component of VKOR, recycles vitamin K 2, 3-epoxide to vitamin K hydroquinone. This cofactor is required by c-glutamyl carboxylase for the post-translational modification of coagulation factors II, VII, IX, X, etc. VKORC1 has been found to be a molecular target of warfarin and has been hypothesized to play a role in warfarin dosage requirements. 3,4 Although other factors, such as patient age, body weight, illness, dietary...
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