Significance of UGT1A6, UGT1A9, and UGT2B7 genetic variants and their mRNA expression in the clinical outcome of renal cell carcinoma.

UDP-glucuronosyltransferase (UGT) metabolizes a number of endogenous and exogenous substrates. Renal cells express high amounts of UGT; however, the significance of UGT in patients with renal cell carcinoma (RCC) remains unknown. In this study, we profile the mRNA expression of UGT subtypes (UGT1A6, UGT1A9, and UGT2B7) and their genetic variants in the kidney tissue of 125 Japanese patients with RCC (Okayama University Hospital, Japan). In addition, we elucidate the association between the UGT variants and UGT mRNA expression levels and clinical outcomes in these patients. The three representative genetic variants, namely, UGT1A6 541A > G, UGT1A9 i399C > T, and UGT2B7-161C > T, were genotyped, and their mRNA expression levels in each tissue were determined. We found that the mRNA expression of the three UGTs (UGT1A6, UGT1A9, and UGT2B7) are significantly downregulated in RCC tissues. Moreover, in patients with RCC, the UGT2B7-161C > T variant and high UGT2B7 mRNA expression are significantly correlated with preferable cancer-specific survival (CSS) and overall survival (OS), respectively. As such, the UGT2B7-161C > T variant and UGT2B7 mRNA expression level were identified as significant independent prognostic factors of CSS and CSS/OS, respectively. Taken together, these findings indicate that UGT2B7 has a role in RCC progression and may, therefore, represent a potential prognostic biomarker for patients with RCC.

Effect of CYP3A5*3 genetic variant on the metabolism of direct-acting antivirals in vitro: a different effect on asunaprevir versus daclatasvir and beclabuvir.

Direct-acting antivirals, asunaprevir (ASV), daclatasvir (DCV), and beclabuvir (BCV) are known to be mainly metabolized by CYP3A enzymes; however, the differences in the detailed metabolic activities of CYP3A4 and CYP3A5 on these drugs are not well clarified. The aim of the present study was to elucidate the relative contributions of CYP3A4 and CYP3A5 to the metabolism of ASV, DCV, and BCV, as well as the effect of CYP3A5*3 genetic variant in vitro. The amount of each drug and their major metabolites were determined using LC-MS/MS. Recombinant CYP3As and CYP3A5*3-genotyped human liver microsomes (CYP3A5 expressers or non-expressers) were used for the determination of their metabolic activities. The contribution of CYP3A5 to ASV metabolism was considerable compared to that of CYP3A4. Consistently, ASV metabolic activity in CYP3A5 expressers was higher than those in CYP3A5 non-expresser. Moreover, CYP3A5 expression level was significantly correlated with ASV metabolism. In contrast, these observations were not found in DCV and BCV metabolism. To our knowledge, this is the first study to directly demonstrate the effect of CYP3A5*3 genetic variants on the metabolism of ASV. The findings of the present study may provide basic information on ASV, DCV, and BCV metabolisms.

Minor contribution of CYP3A5 to the metabolism of hepatitis C protease inhibitor paritaprevir in vitro.

Paritaprevir (PTV) is a non-structural protein 3/4A protease inhibitor developed for the treatment of hepatitis C disease as a fixed dose combination of ombitasvir (OBV) and ritonavir (RTV) with or without dasabuvir. The aim of this study was to evaluate the effects of cytochrome P450 (CYP) 3A5 on in vitro PTV metabolism using human recombinant CYP3A4, CYP3A5 (rCYP3A4, rCYP3A5) and human liver microsomes (HLMs) genotyped as either CYP3A5*1/*1, CYP3A5*1/*3 or CYP3A5*3/*3. The intrinsic clearance (CLint, Vmax/Km) for the production of a metabolite from PTV in rCYP3A4 was 1.5 times higher than that in rCYP3A5. The PTV metabolism in CYP3A5*1/*1 and CYP3A5*1/*3 HLMs expressing CYP3A5 was comparable to that in CYP3A5*3/*3 HLMs, which lack CYP3A5. CYP3A4 expression level was significantly correlated with PTV disappearance rate and metabolite formation. In contrast, there was no such correlation found for CYP3A5 expression level. This study represents that the major CYP isoform involved in PTV metabolism is CYP3A4, with CYP3A5 having a minor role in PTV metabolism. The findings of the present study may provide foundational information on PTV metabolism, and may further support dosing practices in HCV-infected patients prescribed PTV-based therapy.

A randomized controlled, open-label early phase II trial comparing incidence of FOLFIRI.3-induced diarrhoea between Hangeshashinto and oral alkalization in Japanese patients with colorectal cancer.

WHAT IS KNOWN AND OBJECTIVE: We conducted a pilot clinical trial to investigate whether Hangeshashinto (TJ-14) could be substituted for oral alkalization in patients scheduled to undergo chemotherapy by FOLFIRI.3 regimen for colorectal cancer (CRC). METHODS: Patients with CRC were randomized 1:1 to a TJ-14 (7.5 g/day) group or an oral alkalization (sodium bicarbonate, 1.8 g/day; ursodeoxycholic acid, 300 mg/day) group. The primary endpoint was incident of late-onset diarrhoea. A total of 30 patients were randomized to either the TJ-14 group or the alkalization group. RESULTS AND DISCUSSION: There was no statistical difference in age, concomitantly used drugs or UGT1A1 genotypes between the groups. In the alkalization group (n = 15), the frequency of grade 0/1/2 and grade 3 diarrhoea was 73% and 27%, respectively. In the TJ-14 group (n = 14), the frequency of grade 0/1/2 and grade 3 diarrhoea was 79% and 21%, respectively. Grade 4 diarrhoea was not observed in either group. There was no statistically significant difference in other adverse events or in response to FOLFIRI.3 between the groups. WHAT IS NEW AND CONCLUSION: This pilot trial suggests that TJ-14 is a promising alternative treatment option to reduce FOLFIRI.3-induced late-onset diarrhoea, although additional clinical study with a larger number of patients is necessary to confirm these results.

Efficacy of 2.5-mg Prasugrel in Elderly or Low-Body-Weight Patients.

BACKGROUND: Due to concern about bleeding complications, a maintenance dose of prasugrel 2.5 mg may be used in elderly or low-body-weight patients in Japan. There is little information, however, on the efficacy and safety of a 2.5-mg maintenance dose of prasugrel. Methods and Results: In this single-center, prospective, open-label, cross-over study, a total of 44 elderly (≥75 years old) or low body-weight (<50 kg) Japanese patients >1 month after percutaneous coronary intervention who were treated with aspirin 81-100 mg and clopidogrel 75 mg were randomized to either prasugrel 2.5 mg or 3.75 mg instead of clopidogrel for 14 days, with a cross-over directly to the alternate treatment for another 14 days. Platelet inhibition was assessed with the VerifyNow assay (Accumetrics, San Diego, CA, USA) at 3 time points: baseline; day 14; and day 28. P2Y12 reaction units (PRU) ≤95 was defined as low on-treatment platelet reactivity (LPR), and PRU ≥262 as high on-treatment platelet reactivity (HPR). The prevalence of LPR was 2.2% in patients treated with clopidogrel, 2.2% in those with prasugrel 2.5 mg, and 22.7% in those with prasugrel 3.75 mg (P<0.001). Clopidogrel resulted in the higher prevalence of HPR compared with 2.5-mg and 3.75-mg prasugrel (40.9% vs. 18.2% vs. 6.8%, P<0.001). CONCLUSIONS: Prasugrel 2.5 mg may be more appropriate in elderly or lower-body-weight Japanese patients.

An extremely high bioavailability of orally administered vancomycin in a patient with severe colitis and renal insufficiency.

Because there is little absorption of orally administered vancomycin hydrochloride (VCM) through the normal intestinal microvillus membrane, the pharmacokinetics of VCM absorbed from the digestive tract are mostly unknown. Here we report a case of severe colitis and renal insufficiency in which the serum concentration of VCM reached the supratherapeutic range after oral administration. A 54-year-old man receiving outpatient chemotherapy for rectal cancer was admitted to our hospital for severe sepsis and acute renal failure. Multimodal therapy including continuous renal replacement therapy (CRRT) and mechanical ventilation was initiated, and oral VCM administration (0.5 g every 6 h) was begun for suspected severe pseudomembranous colitis with large amounts of watery stool. Despite continued CRRT, the serum VCM concentration increased to 30.6 µg/mL after 4 days. Based on pharmacokinetic analysis, the bioavailability of VCM was estimated to be over 54.5%. Colonoscopy showed that the mucosa was severely damaged throughout the large intestine, resulting in considerable exudation of plasma and blood. This case indicates the need for careful and early monitoring during high-dose oral VCM administration to patients with severe mucosal injury and renal insufficiency.

Increased platelet inhibition after switching from maintenance clopidogrel to prasugrel in Japanese patients with stable coronary artery disease.

BACKGROUND: The pharmacodynamic effects of changing from standard-dose clopidogrel to low-dose (3.75 mg) prasugrel in Japanese patients are largely unknown. METHODS AND RESULTS: A total of 53 consecutive Japanese patients with stable coronary artery disease (CAD) who received aspirin and clopidogrel were enrolled. Clopidogrel was switched to 3.75 mg prasugrel. At day 14, prasugrel was switched to 75 mg clopidogrel. Platelet reactivity was measured using the VerifyNow assay at baseline, day 14, and day 28. VerifyNow P2Y12 reaction units (PRU) >208 was defined as high on-treatment platelet reactivity (HPR). The prevalence of HPR (18.9% vs. 41.5% vs. 44.2%, P<0.001) and the PRU level (154.3±54.2 vs. 196.2±55.5 vs. 194.6±55.8, P<0.001) were significantly lower on prasugrel maintenance therapy compared with the clopidogrel therapy before and after switching. The CYP2C19 genotypes that account for the 3 phenotypes (ie, extensive metabolizer, intermediate metabolizer, and poor metabolizer) had a significant impact on platelet reactivity with clopidogrel (174.9±54.0 vs. 193.1±56.5 vs. 240.6±25.4 PRU, P<0.001) but not prasugrel (147.0±51.9 vs. 147.5±58.3 vs. 184.4±38.3 PRU, P=0.15). CONCLUSIONS: Low-dose prasugrel achieves stronger platelet inhibition than clopidogrel in Japanese patients with stable CAD.

A comparison between the adverse event profiles of patients receiving palbociclib and abemaciclib: analysis of two real-world databases.

BACKGROUND: Palbociclib and abemaciclib are cyclin-dependent kinase (CDK) 4/6 inhibitors currently used to treat breast cancer. Although their therapeutic efficacies are considered comparable, differences in adverse event (AE) profiles of the two drugs remain unclear. AIM: We analysed two real-world databases, the World Health Organization's VigiBase and the Food and Drug Administration Adverse Event Reporting System (FAERS), to identify differences in AE profiles of palbociclib and abemaciclib. METHOD: Data of patients with breast cancer receiving palbociclib or abemaciclib recorded until December 2022 were extracted from the VigiBase and FAERS databases. In total, 200 types of AEs were analysed. The reporting odds ratios were calculated using a disproportionality analysis. RESULTS: Cytopenia was frequently reported in patients receiving palbociclib, whereas interstitial lung disease and diarrhoea were frequently reported in those receiving abemaciclib. Moreover, psychiatric and nervous system disorders were more common in the palbociclib group, whereas renal and urinary disorders were more common in the abemaciclib group. CONCLUSION: This study is the first to show comprehensively the disparities in the AE profiles of palbociclib and abemaciclib. The findings highlight the importance of considering these differences when selecting a suitable CDK4/6 inhibitor to ensure safe and favourable outcomes for patients with breast cancer.

Adverse events of nivolumab plus ipilimumab versus nivolumab plus cabozantinib: a real-world pharmacovigilance study.

BACKGROUND: No head-to-head clinical trials have compared the differences in adverse events (AEs) between nivolumab plus ipilimumab (NIVO-IPI) and nivolumab plus cabozantinib (NIVO-CABO) in the treatment of metastatic renal cell carcinoma (mRCC). AIM: We analysed the two largest real-world databases, the U.S. Food and Drug Administration Adverse Event Reporting System (FAERS) and the World Health Organization's VigiBase, to elucidate the differences in AEs between NIVO-IPI and NIVO-CABO. METHOD: In total, 40,376 and 38,022 records were extracted from FAERS and VigiBase, and 193 AEs were analysed. The reporting odds ratios (ROR) with 95% confidence interval were calculated using a disproportionality analysis (NIVO-CABO/NIVO-IPI). RESULTS: The reported numbers of immune-related AEs, including myocarditis, colitis, and hepatitis, were significantly higher with NIVO-IPI (ROR = 0.18 for FAERS and 0.13 for VigiBase). Contrarily, the reported numbers of other AEs, including gastrointestinal disorders (ROR = 2.68 and 2.92) and skin and subcutaneous tissue disorders (ROR = 2.94 and 3.55), considered to be potentiated by the combination of NIVO and CABO, were higher with NIVO-CABO. CONCLUSION: Our findings contribute to the selection and clinical management of NIVO-IPI and NIVO-CABO, which minimizes the risk of AEs for individual patients with mRCC by considering distinctive differences in the AE profiles.

Functional characterization of seven single-nucleotide polymorphisms of the steroid sulfatase gene found in a Japanese population.

Steroid sulfatase (STS) is an enzyme that hydrolyzes steroid sulfates such as dehydroepiandrosterone sulfate (DHEA-S) and estrone sulfate. STS has a key role in the synthesis of steroid hormones in placenta and breast cancer cells. Recently, we have identified six novel single-nucleotide polymorphisms (SNPs) and one nonsynonymous SNP (V476M) in the STS gene in a Japanese population. To clarify the effects of SNPs in the 5'-flanking region or 5' untranslated region on transcriptional activity, a reporter gene assay was conducted. In addition, DHEA-S desulfatase activity of a variant (Met at codon 476)-type enzyme was compared with that of the wild (Wd)-type enzyme in COS-1 cells. The transcriptional activities were significantly decreased (155A) and increased (-2837A and -1588C) in MCF-7 cells. On the other hand, no significant difference was found in expression levels of STS protein or specific activities of DHEA-S desulfation between Wd and the variant enzymes. This is the first report on the effects of various SNPs in the STS gene detected in Japanese healthy subjects.

Adverse Events of Axitinib plus Pembrolizumab Versus Lenvatinib plus Pembrolizumab: A Pharmacovigilance Study in Food and Drug Administration Adverse Event Reporting System.

No head-to-head postmarket surveillance study has compared the differences in adverse events (AEs) between two combination therapies, axitinib (AXI) + pembrolizumab (PEMBRO) and lenvatinib (LEN) + PEMBRO, against metastatic renal cell carcinoma. This study aims to highlight the comprehensive differences in AEs between these two therapies based on the real-world big data from the Food and Drug Administration Adverse Event Reporting System (FAERS) database. In total, 28 937 records were extracted from the FAERS database, and 139 AEs grouped into the System Organ Class according to the Medical Dictionary for Regulatory Activities were analysed. Logistic regression analyses were performed, and the reporting odds ratio with a 95% confidence interval was determined. We found that the incidences of cardiac and hepatobiliary disorders for AXI + PEMBRO, and blood and lymphatic system, metabolism and nutrition, and vascular disorders for LEN + PEMBRO, all of which were associated with serious AEs, were higher than those for LEN + PEMBRO and AXI + PEMBRO, respectively. The differences in the AEs between AXI + PEMBRO and LEN + PEMBRO were not derived merely from those between AXI and LEN monotherapies. Furthermore, remarkable AE potentiation was observed for AXI + PEMBRO. As FAERS is a spontaneous reporting system comprising partially limited information, analysing more detailed relationships between AEs and patient or treatment characteristics was challenging in this study. The present study is the first to show the overall real-world postmarketing differences in AEs between AXI + PEMBRO and LEN + PEMBRO. Our novel findings will substantially improve clinical practice; we recommend comparing patients' conditions associated with the above AEs when selecting between these two therapies. PATIENT SUMMARY: Herein, we highlight the differences in adverse events (AEs) between axitinib + pembrolizumab and lenvatinib + pembrolizumab therapies using data from the real-world Food and Drug Administration Adverse Event Reporting System database aimed at patients with metastatic renal cell carcinoma. We identified AEs that needed attention in each combination. We recommend the differences in AEs to be considered when selecting these two therapies.

Correlation between antizyme 1 and differentiation of vascular smooth muscle cells cultured in honeycomb-like type-I collagen matrix.

Vascular smooth muscle cells (SMC) are able to proliferate when cultured on plates, but become differentiated when maintained in three-dimensional type I collagen matrices (honeycombs). SMC grown in honeycombs contained a low level of polyamines due to the presence of antizyme 1 (AZ1), a negative regulator of ornithine decarboxylase (ODC) and of polyamine uptake. To clarify the role of AZ1 in differentiation of SMC in honeycombs, an ODC gene was stably transfected into SMC (ODC-SMC). Although proliferation of ODC-SMC on plates was accelerated together with an increase in phosphorylated focal adhesion kinase (FAK) and a decrease in α-actin and myosin, maker proteins of differentiation, growth of ODC-SMC ceased in honeycombs similarly to normal SMC with a low level of phosphorylated FAK and a high level of α-actin and myosin. AZ1 expression in ODC-SMC on plates was low, but that in honeycombs was high. Antizyme in ODC-SMC in honeycombs not only decreased the level of ODC but also inhibited polyamine uptake activity. These results taken together suggest that low levels of polyamines caused by AZ1 in SMC in honeycombs inhibit phosphorylation of FAK and enhance expression of α-actin and myosin, resulting in differentiation through inhibition of focal adhesions.

Differential Impact of Clinical and Genetic Factors on High Platelet Reactivity in Patients with Coronary Artery Disease Treated with Clopidogrel and Prasugrel.

AIM: High platelet reactivity (HPR) is associated with increased risks of thrombotic events in patients with coronary artery disease. The recently developed ABCD-GENE score identified five clinical and genetic factors (age, body mass index, chronic kidney disease, diabetes, and the CYP2C19 loss-of-function allele) for HPR, although the significance of various stages of each factor is unclear. METHODS: Four prospective studies were pooled, in which platelet reactivity was measured using the VerifyNow assay with clopidogrel and prasugrel; genotyping of CYP2C19 was also performed. Each component of the ABCD-GENE score was divided into three subcategories. VerifyNow P2Y12 reactivity units ＞208 were defined as HPR. RESULTS: A total of 184 patients were included, of which 111 (60%) and 51 (28%) had HPR with clopidogrel and prasugrel. Chronic kidney disease had an impact on HPR on both clopidogrel and prasugrel, whereas the impact of diabetes was more evident in patients treated with prasugrel. Although the number of CYP2C19 loss-of-function alleles was clearly associated with a likelihood of HPR with clopidogrel, P2Y12 reactivity units with prasugrel treatment were also significantly and progressively higher in patients with more CYP2C19 loss-of-function alleles. CONCLUSIONS: Clinical and genetic factors had a differential effect on a P2Y12 inhibitor reactivity with clopidogrel and prasugrel in patients with coronary artery disease. The severity of the factors also had a different impact on HPR.

Derivation of a Novel Scoring System Predicting High Platelet Reactivity on Prasugrel in Patients with Coronary Artery Disease.

AIMS: High platelet reactivity (HPR) has been associated with an increased risk of thrombotic events in patients undergoing percutaneous coronary intervention. HPR has been well examined in patients treated with clopidogrel; however, HPR on prasugrel is poorly investigated. METHODS: Four prospective studies were pooled, in which platelet reactivity on prasugrel was measured using VerifyNow assay; genotyping of CYP2C19 was also performed. Factors associated with HPR on prasugrel were identified using multivariable analysis to develop a risk prediction model. RESULTS: In total, 180 patients were examined in this study, of whom 51 (28%) had HPR on prasugrel. The multivariable analysis indicated that hypertension, diabetes, hemodialysis, and the number of CYP2C19 loss-of-function (LOF) alleles are significant factors for HPR on prasugrel. These four factors were then incorporated to develop the HHD-GENE score. The receiver operating characteristic curve analysis showed that the HHD-GENE score predicted HPR on prasugrel (area under the curve (AUC) 0.74, best cutoff value 5, p＜0.001). With the best cutoff value, patients with the HHD-GENE score ≥ 5 had a significantly increased risk of HPR on prasugrel than their counterpart (50% vs. 18%, p＜0.001). CONCLUSIONS: The HHD-GENE score consisting of hypertension, diabetes, hemodialysis, and CYP2C19 LOF alleles may be useful in identifying patients on prasugrel who are at high risk for HPR. External validation is needed to define the clinical utility of this novel scoring system.

Degradation of filamin induces contraction of vascular smooth muscle cells in type-I collagen matrix honeycombs.

BACKGROUND: Dedifferentiated rabbit vascular smooth muscle cells (SMCs) exhibit similar features to differentiated SMCs when cultured in three-dimensional matrices of type-I collagen called "honeycombs," but the mechanism is unknown. The role of filamin, an actin-binding protein that links actin filaments in SMCs, was investigated. METHODS: Filamin and other related proteins were detected by western blot analysis and immunofluorescence staining. Honeycomb size was measured to confirm the contraction of SMCs. RESULTS: Full-length filamin was expressed in subconfluent SMCs cultured on plates; however, degradation of filamin, which might be regulated by calpain, was observed in confluent SMCs cultured on plates and in honeycombs. While filamin was co-localized with ß-actin in subconfluent SMCs grown on plates, filamin was detected in the cytoplasm in SMCs cultured in honeycombs, and degraded filamin was mainly detected in the cytoplasmic fraction of these cells. In addition, ß-actin expression was low in the cytoskeletal fraction of SMCs cultured in honeycombs compared with cells cultured on plates, and the size of the honeycombs used for culturing SMCs was significantly reduced. CONCLUSION: These data suggest that degradation of filamin in SMCs cultured in honeycombs induces structural weakness of ß-non-muscle actin filaments, thereby permitting SMCs in honeycombs to achieve contractility.

Q172H replacement overcomes effects on the metabolism of cyclophosphamide and efavirenz caused by CYP2B6 variant with Arg262.

There are a number of reports indicating that CYP2B6*6 (c.516G>T and c.785A>G) is responsible for decreased clearance of efavirenz (EFV), although increased disposition of cyclophosphamide (CPA) in individuals with this polymorphism was observed. Thus, we hypothesized that the effects of the two single nucleotide polymorphisms (SNPs) of CYP2B6*6 on the metabolism of drugs might be considerably different between these two agents. To clarify this possibility, we expressed two major variants of this enzyme, CYP2B6.6 (Q172H and K262R) and CYP2B6.4 (K262R), and investigated metabolic activities of these variants toward EFV and CPA. Kinetic analyses clearly indicated that CYP2B6.4 possessed enhanced metabolic activity toward EFV compared with that of the wild-type enzyme (CYP2B6.1), whereas CPA was metabolized less efficiently by CYP2B6.4 than by CYP2B6.1. On the other hand, CYP2B6.6 showed a completely opposite character, suggesting that Q172H gives inverse effects on metabolic activities of CYP2B6 affected by K262R. Although it is recognized that effects of amino acid change in cytochrome P450 on the metabolic activity depend on substrates, this study revealed SNPs giving an opposite effect on the metabolism of two clinically important drugs currently used. Furthermore, this study provides the first evidence that Q172H can reverse the direction of the effect caused by K262R in CYP2B6 on the metabolism of certain drugs.

Validation of the ABCD-GENE score to identify high platelet reactivity in east Asian patients undergoing percutaneous coronary intervention.

BACKGROUND: High platelet reactivity (HPR) is associated with subsequent thrombotic events in patients undergoing percutaneous coronary intervention (PCI). Recently, the ABCD-GENE score was developed to identify patients at risk for HPR, incorporating both clinical and genetic factors. However, this score was derived and validated in mostly Caucasian subjects and it has not been validated in an East Asian population. METHOD: Individual patient data from 4 prospective studies were pooled, in which platelet reactivity was measured using the VerifyNow assay on clopidogrel and genotyping of CYP2C19 was performed after PCI. Study populations included patients with general stable coronary artery disease, hemodialysis, age ≥75 and/or body weight <50 kg, and acute coronary syndrome. VerifyNow P2Y12 reactivity units >208 was defined as HPR. RESULTS: Of 184 patients, 111 (60%) had HPR on clopidogrel. In the receiver operating characteristics curve analyses, the ABCD-GENE score significantly predicted HPR on clopidogrel (AUC 0.78, best cut-off value 9, p < 0.001). Across the 4 studies and their combinations, the diagnostic ability and cut-off values of ABCD-GENE score for HPR on clopidogrel were consistent. CONCLUSIONS: The ABCD-GENE score had significant and moderate diagnostic ability for HPR on clopidogrel in Japanese patients undergoing PCI. The predictivity was consistent across a broad spectrum of patient populations, suggesting the applicability of this novel scoring system in clinical practice worldwide.

Relevance of CYP3A5 Expression on the Clinical Outcome of Patients With Renal Cell Carcinoma.

BACKGROUND/AIM: This study aimed to elucidate the detailed characteristics of CYP3A5 expression and the association between CYP3A5 expression and clinical outcomes in patients with renal cell carcinoma (RCC). PATIENTS AND METHODS: This study retrospectively enrolled 124 Japanese patients with RCC treated at the Okayama University Hospital. The commonest CYP3A5 gene polymorphism, CYP3A5*3, and expression levels of CYP3A5 mRNA and protein in each tissue were examined. RESULTS: Expression of CYP3A5 mRNA and protein in RCC tissues was significantly down-regulated compared to that in adjacent normal tissues. High level of CYP3A5 mRNA expression significantly extended cancer-specific survival (p=0.004) and overall survival (p=0.002). The CYP3A5 mRNA expression level was identified as a significant independent prognostic factor for both cancer-specific survival and overall survival. CONCLUSION: CYP3A5 could serve as a potential marker for prognostication and treatment planning for patients with RCC.

Blood concentrations of tacrolimus upon conversion from rabeprazole to vonoprazan in renal transplant recipients: Correlation with cytochrome P450 gene polymorphisms.

We evaluated the impact of vonoprazan on blood concentrations of tacrolimus via a retrospective analysis of 52 renal transplant recipients who took tacrolimus and converted from rabeprazole to vonoprazan between August 2018 and September 2019. We compared tacrolimus trough levels upon conversion among groups that were classified based on cytochrome P450 (CYP) gene polymorphisms. CYP3A5 groups were heterozygous or homozygous for CYP3A5∗1 and CYP3A5∗3 alleles. CYP2C19 genotypes were classified as extensive (∗1/∗1), intermediate (∗1/∗2 and ∗1/∗3) or poor metabolizers (∗2/∗2, ∗2/∗3 and ∗3/∗3). Tacrolimus trough levels increased only 0.3 ng/mL upon conversion in the CYP3A5∗3/∗3 group: 5.8 [3.4-7.2] vs 6.1 [3.8-7.9]; p = 0.06. No statistically significance changes in tacrolimus levels also occurred in the CYP3A5∗1/∗1 or CYP3A5∗1/∗3 groups. Subgroup analyses of CYP3A5∗3/∗3 demonstrated low changes for all three CYP2C19 subgroups: 5.2 [4.3-6.5] vs 6.2 [4.3-7.9]; p = 0.07, 6.1 [3.4-7.2] vs 6.7 [4.6-7.9]; p = 0.12 and 5.4 [3.6-6.5] vs 4.7 [3.8-6.3]; p = 1.00, respectively. Conversion to vonoprazan thus resulted in little increase of tacrolimus trough levels, even in the group predicted to be most susceptible (CYP3A5∗3/∗3 and 2C19∗1/∗1), thus supporting the safety of concomitant use of vonoprazan with tacrolimus.

Growth inhibition and differentiation of cultured smooth muscle cells depend on cellular crossbridges across the tubular lumen of type I collagen matrix honeycombs.

Although rabbit vascular smooth muscle cells (SMCs) showed a differentiated phenotype in three-dimensional type I collagen matrices (honeycombs, diameter of pores=200-500 microm), mouse vascular SMCs proliferated in honeycombs having the same pore size. Here we investigated the relationship between pore sizes of honeycombs and differentiation of SMCs using various pore sizes of honeycombs. Rabbit SMCs (length: 200+/-32 microm) and mouse SMCs (49+/-10 microm) formed crossbridges in honeycombs with 200-300 microm and less than 200 microm of pores, respectively. Both SMCs spread on the inner wall but did not form crossbridges in honeycombs with larger pores. [(3)H]Thymidine incorporation and cell number of both SMCs were decreased when the crossbridges were formed in honeycombs. Because proliferation inhibition and crossbridge formation were observed in the culture of rabbit and mouse SMCs using 200-300 microm and less than 200 microm pore sized honeycombs, respectively, these data suggested that forming crossbridges was important for the inhibition of proliferation of SMCs. Rabbit SMCs differentiation was accompanied by the expression of caldesmon heavy chain when cultured in honeycombs having less than 300 microm pores. Proliferation of mouse SMCs stopped in honeycombs having less than 200 microm pores, but caldesmon heavy chain was not detected despite the expression of its mRNA. Proliferation of SMCs stopped on plates when cells reached confluent state, however, caldesmon heavy chain was not expressed. These data suggested that an appropriate structure and suitable honeycomb pore size are important for the differentiation of SMCs.