A risk-stratified therapy for infants with acute lymphoblastic leukemia: a report from the JPLSG MLL-10 trial.

The prognosis for infants with acute lymphoblastic leukemia (ALL), particularly those with KMT2A gene rearrangement (KMT2A-r), is dismal. Continuous efforts have been made in Japan to investigate the role of hematopoietic stem cell transplantation (HSCT) for infants with KMT2A-r ALL, but improvement in outcome was modest. In the Japanese Pediatric Leukemia/Lymphoma Study Group MLL-10 trial, infants with ALL were stratified into 3 risk groups (low risk [LR], intermediate risk [IR], and high risk [HR]) according to KMT2A status, age, and presence of central nervous system leukemia. Children's Oncology Group AALL0631 modified chemotherapy with the addition of high-dose cytarabine in early intensification was introduced to KMT2A-r patients, and the option of HSCT was restricted to HR patients only. The role of minimal residual disease (MRD) was also evaluated. Ninety eligible infants were stratified into LR (n = 15), IR (n = 19), or HR (n = 56) risk groups. The 3-year event-free survival (EFS) rate for patients with KMT2A-r ALL (IR + HR) was 66.2% (standard error [SE], 5.6%), and for those with germline KMT2A (KMT2A-g) ALL (LR), the 3-year EFS rate was 93.3% (SE, 6.4%). The 3-year EFS rate was 94.4% (SE, 5.4%) for IR patients and 56.6% (SE, 6.8%) for HR patients. In multivariable analysis, female sex and MRD ≥0.01% at the end of early consolidation were significant factors for poor prognosis. Risk stratification and introduction of intensive chemotherapy in this study were effective and were able to eliminate HSCT for a subset of infants with KMT2A-r ALL. Early clearance of MRD seems to have translated into favorable outcomes and should be incorporated into risk stratifications in future trials. This trial was registered at the University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR) as #UMIN000004801.

In Vitro Inhibitory Effects of Sesamin on CYP4F2 Activity.

Sesamin is a major lignan in sesame seeds, and a recent meta-analysis of controlled trials indicated that sesamin intake decreases blood pressure. The antihypertensive effect of sesamin has been suggested to be due to sesamin-mediated suppression of 20-hydroxyeicosatetraenoic acid production catalyzed by CYP4F2. However, the detailed mechanism underlying inhibition of CYP4F2 function by sesamin remains unclear. In this study, the effects of sesamin on catalytic activity of CYP4F2 were investigated in vitro. Sesamin inhibited luciferin-4F2/3 O-dealkylase activity of recombinant human CYP4F2 with an IC50 value of 0.381 µM. When preincubated in the presence of reduced nicotinamide adenine dinucleotide phosphate (NADPH) for 20 min, sesamin potentiated the inhibition of CYP4F2 activity. Moreover, kinetic analysis of the inactivation revealed that sesamin showed a preincubation time- and concentration-dependent inhibition of CYP4F2 activity yielding a maximal inactivation rate constant (kinact) value of 0.354 min-1 and half-maximal inhibitory concentration (KI) value of 1.12 µM. The inactivation of CYP4F2 by sesamin required NADPH. These results indicated that sesamin is a mechanism-based inactivator of human CYP4F2.

Changing clinical and molecular characteristics of hepatitis E virus infection in Mie Prefecture, Japan: Disappearance of indigenous subtype 3e strains.

AIM: To evaluate the clinical and molecular characteristics of hepatitis E virus (HEV) infection in Mie Prefecture, Japan, from 2004 through 2018. METHODS: The clinical information of hepatitis E cases was collected from 21 medical institutions in Mie Prefecture. The nucleotide sequences of infecting HEV strains were determined for cases with available serum samples. The origins or transmission routes were inferred from phylogenetic analyses of the nucleotide sequences. RESULTS: Fifty-three patients were diagnosed with HEV infection. The number of cases increased each year through 2012 and then decreased. Analyses of the clinical characteristics of the cases indicated that even mild cases were detected in the latter 10 years of the study. Nucleotide sequence analyses were undertaken on 38 of the 53 cases. The HEV subtype 3e (HEV-3e) strains identified for 13 cases were closely related to a swine HEV-3e strain that was isolated from the liver of a pig bred in Mie Prefecture. The number of cases infected with the indigenous Mie HEV-3e strains increased until 2012 but have not been reported since 2014. In the latter half of the study, cases involving various HEV strains of different genotypes and subtypes emerged. CONCLUSIONS: The disappearance of indigenous Mie HEV-3e strains appeared to be the primary cause for the decrease in hepatitis E cases in Mie Prefecture. The disappearance might have been associated with improved hygienic conditions on pig farms or the closure of contaminated farms. The results suggest that indigenous HEV strains can be eradicated by appropriate management.

Influence of azole antifungal drugs on blood tacrolimus levels after switching from intravenous tacrolimus to once-daily modified release tacrolimus in patients receiving allogeneic hematopoietic stem cell transplantation.

WHAT IS KNOWN AND OBJECTIVE: Azole antifungal drugs are often co-administered with tacrolimus after allogeneic hematopoietic stem cell transplantation (HSCT). However, the influence of azole antifungal drugs on variation in tacrolimus pharmacokinetics when switching from intravenous tacrolimus (Tac-iv) to once-daily modified release tacrolimus (Tac-MR) remains to be elucidated. This study was performed to evaluate the effects of oral azole antifungal drugs on variation in tacrolimus pharmacokinetics after conversion to Tac-MR in HSCT patients. METHODS: Patients concomitantly receiving fluconazole (FLCZ) or voriconazole (VRCZ) along with tacrolimus were evaluated retrospectively. Blood tacrolimus concentrations before and after changing to oral administration were compared between FLCZ and VRCZ groups. RESULTS AND DISCUSSION: A total of 52 patients (34 FLCZ and 18 VRCZ) were included in the analysis. There were no significant differences in the most recent daily dose (Div ) and blood level (Civ ) of Tac-iv, Civ /Div , and ratio of daily dose of tacrolimus on the first to second day after changing to Tac-MR (Dpo1-2 ) to Div between FLCZ and VRCZ groups (P > 0.2). The trough levels of tacrolimus on the first to second day after switching to Tac-MR (Cpo1-2 ) and on the third to fifth day after the switch (Cpo3-5 ) were significantly higher in the VRCZ group than the FLCZ group (P < 0.05). The values of (Civ /Div )/(Cpo1-2 /Dpo1-2 ) and (Civ /Div )/(Cpo3-5 /Dpo3-5 ) in the VRCZ group were significantly lower compared with those in the FLCZ group (P < 0.05). Furthermore, individual values of (Civ /Div )/(Cpo3-5 /Dpo3-5 ) in the FLCZ group varied widely. WHAT IS NEW AND CONCLUSION: Voriconazole increased blood tacrolimus level more markedly than FLCZ after switching to Tac-MR, whereas FLCZ caused a large variation in tacrolimus blood level. These results suggest that therapeutic monitoring of tacrolimus after the switch may need to be performed carefully considering that orally co-administered VRCZ and FLCZ exhibit different change in blood tacrolimus level just after the switch.

[Desensitization Therapy for Osimertinib in Patients Who Developed Toxic Erythema - Two Case Reports].

We encountered 2 cases of T790M-positive non-small cell lung cancer in patients who developed toxic erythema within a week after initiation of osimertinib(80mg/day)therapy. Since osimertinib was regarded as the suspected drug, we adminis- tered desensitization therapy for osimertinib at an initial dose of 10mg/day. During the process of dose escalation, slight eruption and flare were observed, but we were able to provide appropriate treatment. Osimertinib therapy was continued and conferred tumor reduction in both cases. We report the clinical course and suggest that desensitization therapy is an alternative therapy for patients who present with drug-induced allergic reaction.

A Specific Probe Substrate for Evaluation of CYP4A11 Activity in Human Tissue Microsomes and a Highly Selective CYP4A11 Inhibitor: Luciferin-4A and Epalrestat.

The specificity of cytochrome P450 4A11 (CYP4A11) against luciferin-4A O-demethylation in human liver microsomes (HLMs) and human renal microsomes (HRMs) and selectivity of CYP4A11 inhibition by epalrestat were investigated. Kinetic analysis of luciferin-4A O-demethylation yielded Vmax and S50 values of 39.7 pmol/min per milligram protein and 43.2 µM for HLMs (Hill coefficient 1.24) and 39.4 pmol/min per milligram protein and 33.8 µM for HRMs (Hill coefficient 1.34), respectively. Among the selective CYP inhibitors tested, HET0016 (CYP4 inhibitor) exclusively inhibited luciferin-4A O-demethylation by HLMs and HRMs. Furthermore, anti-CYP4A11 antibody nearly abolished the activity of both tissue microsomes. Luciferin-4A O-demethylase activity of HLMs was significantly correlated with lauric acid ω-hydroxylase activity, a marker of CYP4A11 activity (r = 0.904, P < 0.0001). Next, effects of epalrestat on CYP-mediated drug oxidations were examined. Epalrestat showed the most potent inhibition against CYP4A11 (IC50 = 1.82 µM) among the 17 recombinant enzymes tested. The inhibitory effect of epalrestat on CYP4A11 was at least 10-fold stronger than those on CYP4F2, CYP4F3B, and CYP4F12. For known CYP4 inhibitors, in contrast, HET0016 inhibited the activities of CYP4A11 and CYP4F2 (IC50 = 0.0137-0.0182 µM); 17-octadecynoic acid reduced activities of CYP4A11, CYP4F2, CYP4F3B, and CYP4F12 to a similar extent (IC50 = 5.70-17.7 µM). Epalrestat selectively and effectively inhibited the CYP4A11 activity of HLMs (IC50 = 0.913 µM) and HRMs (IC50 = 0.659 µM). These results indicated that luciferin-4A O-demethylase activity is a good CYP4A11 marker of HLMs and HRMs, and that epalrestat is a more selective CYP4A11 inhibitor compared with known CYP4 inhibitors.

In vitro inhibition of CYP2C9-mediated warfarin 7-hydroxylation by iguratimod: possible mechanism of iguratimod-warfarin interaction.

Iguratimod is a novel disease-modifying antirheumatic drug. A blue letter (safety advisory) for drug interaction between iguratimod and warfarin was issued by the Ministry of Health, Labour and Welfare of Japan in May 2013. Iguratimod may affect warfarin metabolism catalyzed by CYP. However, it is not clear whether iguratimod inhibits warfarin oxidation. This study was performed to investigate the effects of iguratimod on warfarin 7-hydroxylation with human liver microsomes (HLMs) and recombinant CYP enzymes. Iguratimod concentration-dependently inhibited R,S-warfarin 7-hydroxylase activity of HLMs with an IC50 value of 15.2 µM. The inhibitory effect was examined with S-warfarin and R-warfarin to determine which enantiomer was more potently inhibited by iguratimod. Iguratimod potently inhibited the S-warfarin 7-hydroxylase activity of HLMs with an IC50 value of 14.1 µM, but showed only slight inhibition of R-warfarin 7-hydroxylation. Furthermore, iguratimod inhibited the S-warfarin 7-hydroxylase activity of recombinant CYP2C9.1 (rCYP2C9.1) and rCYP2C9.3 in a concentration-dependent manner with IC50 values of 10.8 and 20.1 µM, respectively. Kinetic analysis of the inhibition of S-warfarin 7-hydroxylation by iguratimod indicated competitive-type inhibition for HLMs and rCYP2C9.1 but mixed-type inhibition for rCYP2C9.3. The Ki values for HLMs, rCYP2C9.1, and rCYP2C9.3 were 6.74, 4.23, and 14.2 µM, respectively. Iguratimod did not exert metabolism-dependent inhibition of S-warfarin 7-hydroxylation. These results indicated that iguratimod is a potent direct inhibitor of CYP2C9-mediated warfarin 7-hydroxylation and that its inhibitory effect on CYP2C9.1 was more sensitive than that on CYP2C9.3.

Characterization of sporadic acute hepatitis E and comparison of hepatitis E virus genomes in acute hepatitis patients and pig liver sold as food in Mie, Japan.

AIM: To characterize hepatitis E in Mie prefecture and to investigate whether raw pig liver sold as food in Mie is contaminated with hepatitis E virus (HEV) strains similar to those recovered from patients. METHODS: Seventeen patients with sporadic acute hepatitis E treated from 2004 to 2012 were studied. A total of 243 packages of raw pig liver from regional grocery stores were tested for the presence of HEV RNA. The partial genomic sequences of human and swine HEV isolates were determined and subjected to the phylogenetic analyses. RESULTS: The HEV isolates recovered from the 17 patients segregated into genotype 3 (n = 15) and genotype 4 (n = 2), and 15 genotype 3 isolates further segregated into 3e (n = 11) and 3b (n = 4). Pig liver specimens from 12 (4.9%) of the 243 packages had detectable HEV RNA. All 12 swine HEV isolates were grouped into genotype 3 (3a or 3b). Although no 3e strains were isolated from pig liver specimens, two 3b swine strains were 99.5-100% identical to two HEV strains recovered from hepatitis patients, within 412-nt partial sequences. CONCLUSION: The 3e HEV was prevalent among hepatitis E patients. HEV RNA was detected in approximately 5% of pig liver sold as food. The presence of identical HEV strains between hepatitis patients and pig liver indicated that pigs play an important role as reservoirs for HEV in humans in Mie. Further studies are needed to clarify the source of 3e HEV in the animal and environmental reservoirs.

Allogeneic Hematopoietic Cell Transplantation for Juvenile Myelomonocytic Leukemia with a Busulfan, Fludarabine, and Melphalan Regimen: JPLSG JMML-11.

Juvenile myelomonocytic leukemia (JMML), which is classified as a myelodysplastic/myeloproliferative neoplasm, is a rare hematologic malignancy of childhood. Most patients with JMML require allogeneic hematopoietic cell transplantation (HCT) as a curative therapy. A Japanese retrospective analysis demonstrated favorable outcomes for a busulfan (BU) + fludarabine (FLU) + melphalan (MEL) regimen, with an overall survival (OS) of 72% and an event-free survival (EFS) of 53%. To further validate the efficacy and safety of this regimen, the Japan Pediatric Leukemia/Lymphoma Study Group (JPLSG) conducted a nationwide prospective study, JMML-11. Between July 2011 and June 2017, 28 patients with newly diagnosed JMML were enrolled in JMML11. Low-dose chemotherapy for tumor control before HCT was recommended, and patients treated with AML-type chemotherapy and azacitidine were excluded. The conditioning regimen comprised i.v. BU, 16 doses administered every 6 h, with dose adjustment based on pharmacokinetic (PK) studies on days -11 to -8; FLU, 30 mg/m2/day or 1 mg/kg/day for patients <10 kg or age <1 year on days -7 to -4; and MEL, 90 mg/m2/day or 3 mg/kg/day for patients <10 kg or <1 year on days -3 to -2. The donor was selected by the physician in charge. A family donor was available for 7 patients (3 HLA-matched siblings, 3 HLA-1-antigen mismatched parents, and 1 haploidentical father). Overall, 21 patients received grafts from unrelated donors, including 8 HLA-matched donors and 13 HLA-mismatched donors. The graft source was related bone marrow (BM) for 7 patients, unrelated BM for 14 patients, and unrelated cord blood for 7 patients. Neutrophil engraftment was achieved in 21 of 28 patients (75%), with a median of 20.5 days (range, 11 to 39 days) after transplantation. The 3-year OS, 3-year EFS, 3-year relapse rate, and 3-year transplantation-related mortality were 63% (95% confidence interval [CI], 42% to 78%), 52% (95% CI, 32% to 69%), 18% (95% CI, 6% to 34%), and 21% (95% CI, 9% to 38%), respectively. WBC count before the conditioning regimen (≥7.0 × 109/L) was significantly associated with inferior EFS and OS. Body surface area ≥.5 m2, spleen size <4 cm before conditioning, and HLA-matched unrelated BM donors were significantly associated with better OS. Adverse effects related to the conditioning regimen included febrile neutropenia (86%), diarrhea (39%), hypoxemia (21%), and mucositis (18%). BU-associated toxicity, including sinusoidal obstruction syndrome (SOS) and thrombotic microangiopathy (TMA), occurred in 7 patients (25%; SOS, n = 6; TMA, n = 2). Retrospective analysis of PK data after the first BU dose in 23 patients, including 6 with SOS and 17 without SOS, did not show significant differences between groups. The JMML-11 study confirms the positive results of previous retrospective analyses. BU+FLU+MEL might become a standard conditioning regimen for patients with JMML.

Safety and effectiveness of low-dose propofol sedation during and after esophagogastroduodenoscopy in child A and B cirrhotic patients.

BACKGROUND: Effective and safe sedation for patients with liver cirrhosis is problematic. AIM: To examine the safety and effectiveness of low-dose propofol sedation during and after esophagogastroduodenoscopy (EGD) in cirrhotic patients. METHODS: Study 1 was a prospective study in cirrhotic patients who underwent diagnostic EGD under propofol sedation. Propofol was given by bolus injection with an age-adjusted standard protocol consisting of 40 mg for patients <70 years, 30 mg for patients aged 70-89 years; additional injections of 20 mg propofol were given up to a maximum of 120 mg. The principal parameter was the occurrence of adverse events within 24 h after EGD. Secondary parameters included successful procedures, complications, and full recovery within 60 min. In Study 2, the residual effects of propofol were evaluated using a driving simulator and blood propofol concentrations in a subset of cirrhotic patients undergoing EGD and compared with healthy individuals. The principal parameter was driving ability. RESULTS: Study 1: Consecutive cirrhotic patients were entered and all 163 successfully completed EGD. The mean dose of propofol was 46 mg (range 30-120 mg). No complications occurred. Full recovery had occurred in 100 % 60 min after the procedure. No adverse events occurred within 24 h after EGD. Study 2: There were no significant differences in blood propofol levels between cirrhotic patients (n = 21) and healthy individuals (n = 20) after sedation. In cirrhotic patients, there was no deterioration in driving ability as compared with healthy individuals. CONCLUSION: Low-dose propofol sedation provided safe and effective sedation for EGD in cirrhotic patients with rapid recovery.

Differentiation of monkey embryonic stem cells to hepatocytes by feeder-free dispersion culture and expression analyses of cytochrome p450 enzymes responsible for drug metabolism.

We reported previously that monkey embryonic stem cells (ESCs) were differentiated into hepatocytes by formation of embryoid bodies (EBs). However, this EB formation method is not always efficient for assays using a large number of samples simultaneously. A dispersion culture system, one of the differentiation methods without EB formation, is able to more efficiently provide a large number of feeder-free undifferentiated cells. A previous study demonstrated the effectiveness of the Rho-associated kinase inhibitor Y-27632 for feeder-free dispersion culture and induction of differentiation of monkey ESCs into neural cells. In the present study, the induction of differentiation of cynomolgus monkey ESCs (cmESCs) into hepatocytes was performed by the dispersion culture method, and the expression and drug inducibility of cytochrome P450 (CYP) enzymes in these hepatocytes were examined. The cmESCs were successfully differentiated into hepatocytes under feeder-free dispersion culture conditions supplemented with Y-27632. The hepatocytes differentiated from cmESCs expressed the mRNAs for three hepatocyte marker genes (α-fetoprotein, albumin, CYP7A1) and several CYP enzymes, as measured by real-time polymerase chain reaction. In particular, the basal expression of cmCYP3A4 (3A8) in these hepatocytes was detected at mRNA and enzyme activity (testosterone 6ß-hydroxylation) levels. Furthermore, the expression and activity of cmCYP3A4 (3A8) were significantly upregulated by rifampicin. These results indicated the effectiveness of Y-27632 supplementation for feeder-free dispersed culture and induction of differentiation into hepatocytes, and the expression of functional CYP enzyme(s) in cmESC-derived hepatic cells.

Psychomotor recovery and blood propofol level in colonoscopy when using propofol sedation.

BACKGROUND: It is commonly recommended that patients refrain from driving for 24 hours after endoscopy for which sedation is given. OBJECTIVE: The aim of this study was to evaluate psychomotor recovery and blood propofol concentrations after colonoscopy with propofol sedation to determine whether driving might be safe. DESIGN: A prospective, consecutive study. SETTING: Municipal hospital outpatients. PATIENTS: This study involved 48 consecutive patients scheduled for colonoscopy with propofol sedation. INTERVENTION: Patient clinical features, psychomotor recovery, and blood concentrations of propofol were assessed. Psychomotor recovery was assessed before colonoscopy and 1 and 2 hours after colonoscopy by using the number connection test and a driving simulator test. MAIN OUTCOME MEASUREMENTS: Clinical features, psychomotor recovery, and blood concentration of propofol. RESULTS: All patients successfully completed the post-sedation assessments. Although there was a significant difference in results of the number connection test between before colonoscopy and 1 hour after colonoscopy, all number connection test results were within normal limits (<40 seconds). Scores were as follows: mean time (standard deviation) before colonoscopy, 32.2 (2.0) seconds (range 29-36 seconds) versus after colonoscopy, 32.7 (2.0) seconds (range 27-38 seconds); P = .0019. Driving skills had recovered to the baseline levels 1 hour after colonoscopy. Scores were as follows: tracking error (%) before colonoscopy, 45.0 (5.6) versus after colonoscopy, 46.0 (5.5); P = .61; accelerating reaction time in seconds before colonoscopy, 0.65 (0.15) versus after colonoscopy, 0.62 (0.14); P = .40; braking reaction time in seconds before colonoscopy, 0.58 (0.13) versus after colonoscopy, 0.61 (0.13); P = .50. LIMITATIONS: Small sample size, single-center study. CONCLUSION: Although consistent findings on the number connection test and driving simulation (psychomotor recovery) test are present as early as 1 hour after propofol sedation, a study of additional numbers of patients as well as different patient populations are needed before these results can be universally recommended.

Influence of cytochrome P450 2C19 gene variations on pharmacokinetic parameters of thalidomide in Japanese patients.

PURPOSE: Cytochrome P450 (CYP)2C19 polymorphisms may partly explain the variability of thalidomide concentration and adverse drug effects by altering its metabolism. To compare the genetic and clinical factors responsible for the adverse effects and efficacy of thalidomide treatment, we investigated CYP2C19 genetic polymorphisms in Japanese subjects. MATERIALS AND METHODS: Variations in the CYP2C19 gene in 6 patients treated with thalidomide were analyzed. The dosage of thalidomide, concentrations of (R)- and (S)-thalidomide in whole blood, and clinical laboratory test results were used as pharmacokinetic and pharmacodynamic indices. Using genomic DNA, CYP2C19*2 and *3 allele frequencies were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assays. RESULTS: The frequencies of CYP2C19 PM and hetero EM (hetEM) genotypes in Japanese patients taking thalidomide were 2 (33.3%) and 4 (66.7%), respectively. The areas under the curve (AUC) of (R)-thalidomide were 3.42 and 5.33 µg·h/L, and those of (S)-thalidomide were 1.64 and 2.46 µg·h/L for hetEM and PM, respectively. CONCLUSIONS: This study provided new insights regarding the contribution of CYP2C19 gene variations to adverse responses to thalidomide. Genotyping of CYP2C19*2 and *3 can be considerably simplified by using KOD FX as a polymerase for prediction of adverse effects to thalidomide by the PCR-RFLP method. CYP2C19 PM patients tend to have high serum thalidomide concentrations.

Effects of acid and lactone forms of statins on S-warfarin 7-hydroxylation catalyzed by human liver microsomes and recombinant CYP2C9 variants (CYP2C9.1 and CYP2C9.3).

The inhibition of CYP2C9-mediated warfarin metabolism by acid or lactone forms of statin converted in the body and effects of CYP2C9 genetic variants on their inhibition are not fully understood. Here, the effects of acid and lactone forms of statins on S-warfarin 7-hydroxylation were investigated in vitro. S-Warfarin 7-hydroxylase activities of human liver microsomes (HLMs), recombinant CYP2C9.1 (rCYP2C9.1), and rCYP2C9.3 (Ile359Leu variant) in the presence of statins were determined by high-performance liquid chromatography. Lactone forms of atorvastatin, lovastatin, pitavastatin, pravastatin, rosuvastatin, and simvastatin inhibited the activity of HLMs more potently than the corresponding acid forms, whereas fluvastatin acid showed stronger inhibition than fluvastatin lactone. When the effects of statins on rCYP2C9 variants were examined, inhibition profiles of acid versus lactone forms of statins except for fluvastatin were similar between rCYP2C9.1 and rCYP2C9.3. However, the degrees of inhibition by atorvastatin lactone, fluvastatin acid, fluvastatin lactone, lovastatin lactone, and pitavastatin lactone (Ki values) were significantly different between these variants. These results indicated that lactone forms of statins other than fluvastatin showed more potent inhibition of CYP2C9-catalyzed S-warfarin 7-hydroxylation than the corresponding acid forms. Furthermore, our results indicated that Ile359Leu substitution in CYP2C9 affected the inhibitory potencies of statins.

Hematopoietic stem cell transplantation for infants with high-risk KMT2A gene-rearranged acute lymphoblastic leukemia.

The role of allogeneic hematopoietic stem cell transplantation (HSCT) for infants with acute lymphoblastic leukemia (ALL) and KMT2A gene rearrangement (KMT2A-r) is controversial in terms of both its efficacy and potential for acute and late toxicities. In Japanese Pediatric Leukemia/Lymphoma Study Group trial MLL-10, by introducing intensive chemotherapy, indication of HSCT was restricted to patients with high-risk (HR) features only (KMT2A-r and either age <180 days or presence of central nervous system leukemia). Of the 56 HR patients, 49 achieved complete remission. Forty-three patients received HSCT in first remission including 38 patients receiving protocol-specified HSCT with conditioning consisting of individualized targeted doses of busulfan, etoposide, and cyclophosphamide. Three-year event-free survival (EFS) of 56.8% (95% confidence interval [CI], 42.4% to 68.8%) and overall survival of 80.2% (95% CI, 67.1% to 88.5%) were accomplished. Univariable analysis showed that Interfant-HR criteria and flow cytometric minimal residual disease (MRD; ≥0.01%), both at the end of induction and at the end of consolidation (EOC), were significantly associated with poorer EFS. In the multivariable analysis, positive MRD at EOC was solely associated with poor EFS (P < .001). Rapid pretransplant MRD clearance and tailored HSCT strategy in the MLL-10 trial resulted in a favorable outcome for infants with HR KMT2A-r ALL. However, considering the high rate of potentially life-threatening toxicities and the risk of late effects, its indication should be further restricted or even eliminated in the future by introducing more effective therapeutic modalities with minimal toxicities. This trial was registered at the University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR) as #UMIN000004801.

Cytochrome P450 3As gene expression and testosterone 6 beta-hydroxylase activity in human fetal membranes and placenta at full term.

Expression levels of cytochrome P450 (CYP) 3A4, CYP3A5 and CYP3A7 mRNAs in placentas and fetal membranes, which were split into amnion and chorion leave attached decidua (chorion/decidua), obtained from pregnant women with normal delivery (5 subjects) and Caesarean section (15 subjects) were determined. These CYP3A mRNAs were also expressed in amnion and chorion/decidua together with placenta, although the expression level of these mRNAs was strikingly different between subjects. The expression level of the CYP3A4 mRNA in the placenta was about 2-fold higher than those in amnion and chorion/decidua. On the other hand, the expression levels of CYP3A5 and CYP3A7 mRNAs were highest in chorion/decidua. The immunologically related protein(s) with CYP3A7 was detected in all tissues examined. Testosterone 6beta-hydroxylase activity in homogenate of human placenta, amnion and chorion/decidua were 26.6, 3.7 and 4.6 pmol/h/mg protein, respectively. These results suggest that CYP3As in fetal membranes have the metabolic function to protect the fetus from exposure to drugs.

Expression profile of cytochrome P450s and effects of polycyclic aromatic hydrocarbons and antiepileptic drugs on CYP1 expression in MOG-G-CCM cells.

AIMS: This study was performed to investigate the expression profile of cytochrome P450 (CYP) isoforms and effects of polycyclic aromatic hydrocarbons (PAHs) and antiepileptic drugs on CYP1 expression in human astrocytoma MOG-G-CCM cells. MAIN METHODS: CYP1A1 and CYP1B1 expression were determined by quantitative real-time polymerase chain reaction, Western blotting, and immunocytochemistry. KEY FINDINGS: MOG-G-CCM cells expressed various CYP isoforms. Among the CYP isoforms analyzed, CYP1B1 showed the highest expression level, followed by CYP1A1. Furthermore, CYP1B1 was localized in both the endoplasmic reticulum and mitochondria. 3-Methylcholanthrene (3-MC), benz[a]anthracene (B[a]A), benzo[a]pyrene (B[a]P), and valproic acid (VPA) increased the expression of CYP1B1 and CYP1A1. The potent aryl hydrocarbon receptor antagonist GNF351 significantly suppressed the 3-MC- and VPA-mediated upregulation of CYP1B1 and CYP1A1. In addition, VPA potentiated the induction of CYP1B1 and CYP1A1 by 3-MC, B[a]A, and B[a]P, although the augmentation of CYP1A1 was more remarkable than that of CYP1B1. In contrast, other antiepileptic drugs (carbamazepine, lamotrigine, levetiracetam, phenytoin) did not affect the 3-MC-mediated upregulation of CYP1B1 and CYP1A1. VPA is known to act as a histone deacetylase (HDAC) inhibitor. Therefore, the effects of trichostatin A, a representative HDAC inhibitor, on CYP1 induction by 3-MC were examined. Trichostatin A enhanced the 3-MC-mediated upregulation of CYP1A1 but not CYP1B1. SIGNIFICANCE: These results partially indicated that VPA may augment the PAH-mediated induction of CYP1B1 and CYP1A1 through the activation of transcription by HDAC inhibition.

Inhibitory effects of antihypertensive drugs on human cytochrome P450 2J2 activity: Potent inhibition by azelnidipine and manidipine.

The inhibitory effects of antihypertensive drugs (dihydropyridine calcium channel blockers, angiotensin II receptor blockers, and angiotensin-converting enzyme inhibitors) on cytochrome P450 2J2 (CYP2J2) activity were examined. Amlodipine, azelnidipine, barnidipine, benidipine, cilnidipine, efonidipine, felodipine, manidipine, nicardipine, nifedipine, nilvadipine, nisoldipine, nitrendipine, telmisartan, delapril, and quinapril inhibited luciferin-2J2/4F12 O-dealkylase activity of recombinant human CYP2J2 in a concentration-dependent manner (IC50 = 0.116-9.19 µM). Kinetic analyses of the inhibition indicated that azelnidipine, barnidipine, benidipine, cilnidipine, efonidipine, manidipine, nicardipine, telmisartan, delapril, and quinapril competitively inhibited CYP2J2 activity, while amlodipine, felodipine, nifedipine, nilvadipine, nisoldipine, and nitrendipine showed mixed inhibition. Among these drugs, manidipine showed the strongest reversible inhibition with Ki value of 0.0294 µM. The docking simulation data supported the potent inhibition of CYP2J2 by these drugs. Next, the effect of preincubation on CYP2J2 inhibition was investigated to determine whether these antihypertensive drugs inhibited CYP2J2 activity in a metabolism-dependent manner. A 20-min preincubation of azelnidipine and felodipine in the presence of NADPH potentiated the inhibition of CYP2J2. Furthermore, kinetic analysis of the inactivation showed that azelnidipine caused a preincubation time- and concentration-dependent decrease in CYP2J2 activity yielding kinact/KI value of 105 l/mmol/min, although felodipine showed no preincubation time-dependent inhibition. The azelnidipine-mediated inactivation required NADPH. These results indicated that manidipine is a potent competitive reversible inhibitor while azelnidipine is a potent mechanism-based inactivator of human CYP2J2.