Protocol for the nationwide registry of patients with polycystic kidney disease: japanese national registry of PKD (JRP)

BACKGROUND

Autosomal dominant polycystic kidney disease (ADPKD) and autosomal recessive polycystic kidney disease (ARPKD) are major genetic polycystic kidney diseases that can progress to end-stage kidney disease (ESKD). Longitudinal data on the clinical characteristics associated with clinical outcomes in polycystic kidney disease (PKD), including the development of ESKD and cardiovascular disease (CVD) are lacking in Japan. To address this unmet need the authors are establishing a novel, web-based, Nationwide Cohort Registry Study-the Japanese Registry of PKD (JRP).

METHODS

The JRP is a prospective cohort study for ADPKD (aim to recruit n = 1000 patients), and both a retrospective and prospective study for ARPKD (aim to recruit n = 100). In the prospective registry, patients will be followed-up for 10 years every 6 months and 12 months for patients with ADPKD and ARPKD, respectively. Data collection will be recorded on Research Electronic Data Capture (REDCap) starting on April 1, 2024, with recruitment ending on March 31, 2029. (jRCT 1030230618).

RESULTS

Data to be collected include: baseline data, demographics, diagnostic and genetic information, radiological and laboratory findings, and therapeutic interventions. During follow-up, clinical events such as development of ESKD, hospitalization, occurrence of extra kidney complications including CVD events, and death will be recorded, as well as patient-reported health-related quality of life for patients with ADPKD.

CONCLUSIONS

The JRP is the first nationwide registry study for patients with ADPKD and ARPKD in Japan, providing researchers with opportunities to advance knowledge and treatments for ADPKD and ARPKD, and to inform disease management and future clinical practice.

Long-Term Effects of Tolvaptan in Autosomal Dominant Polycystic Kidney Disease: Predictors of Treatment Response and Safety over 6 Years of Continuous Therapy

Tolvaptan, an oral vasopressin V2 receptor antagonist, reduces renal volume expansion and loss of renal function in patients with autosomal dominant polycystic kidney disease (ADPKD). Data for predictive factors indicating patients more likely to benefit from long-term tolvaptan are lacking. Data were retrospectively collected from 55 patients on tolvaptan for 6 years. Changes in renal function, progression of renal dysfunction (estimated glomerular filtration rate [eGFR], 1-year change in eGFR [ΔeGFR/year]), and renal volume (total kidney volume [TKV], percentage 1-year change in TKV [ΔTKV%/year]) were evaluated at 3-years pre-tolvaptan, at baseline, and at 6 years. In 76.4% of patients, ΔeGFR/year improved at 6 years. The average 6-year ΔeGFR/year (range) minus baseline ΔeGFR/year: 3.024 (-8.77-20.58 mL/min/1.73 m2). The increase in TKV was reduced for the first 3 years. A higher BMI was associated with less of an improvement in ΔeGFR (p = 0.027), and family history was associated with more of an improvement in ΔeGFR (p = 0.044). Hypernatremia was generally mild; 3 patients had moderate-to-severe hyponatremia due to prolonged, excessive water intake in response to water diuresis-a side effect of tolvaptan. Family history of ADPKD and baseline BMI were contributing factors for ΔeGFR/year improvement on tolvaptan. Hyponatremia should be monitored with long-term tolvaptan administration.

Clinical Practice Guidelines for tuberous sclerosis complex-associated renal angiomyolipoma by the Japanese Urological Association: Summary of the update

New clinical issues have been raised through an interval of 7 years from the previous version (2016). In this study, we update the "Clinical Practice Guidelines for tuberous sclerosis complex-associated renal angiomyolipoma" as a 2023 version under guidance by the Japanese Urological Association. The present guidelines were cooperatively prepared by the Japanese Urological Association and Japanese Society of Tuberous Sclerosis Complex; committee members belonging to one of the two societies or specializing in the treatment of this disease were selected to prepare the guidelines in accordance with the "Guidance for preparing treatment guidelines" published by Minds (2020 version). The "Introduction" consisted of four sections, "Background Questions (BQ)" consisted of four sections, "Clinical Questions (CQ)" consisted of three sections, and "Future Questions (FQ)" consisted of three sections (total: 14 sections). Concerning CQ, an agreement was confirmed through voting by the committee members based on the direction and strength of recommendation, accuracy of evidence, and recommendation comments. The present guidelines were updated based on the current evidence. We hope that the guidelines will provide guiding principles for the treatment of tuberous sclerosis complex-associated renal angiomyolipoma to many urologists, becoming a foundation for subsequent updating.

Public support for patients with intractable diseases in Japan: impact on clinical indicators from nationwide registries in patients with autosomal dominant polycystic kidney disease

BACKGROUND

Clinical practice guidelines recommend antihypertensive and tolvaptan therapies for patients with autosomal dominant polycystic kidney disease (ADPKD) in Japan. However, tolvaptan therapy may pose an economic burden. The Japanese Ministry of Health, Labour and Welfare supports patients with intractable diseases. This study aimed to confirm the impact of the intractable disease system in Japan on the clinical treatment of ADPKD.

METHODS

We analyzed the data of 3768 patients with ADPKD having a medical subsidy certificate from the Japanese Ministry of Health, Labour and Welfare in 2015-2016. The following quality indicators were use: the adherence rate to the 2014 clinical practice guideline for polycystic kidney disease (prescription rates of antihypertensive agents and tolvaptan in this cohort) and the number of Japanese patients with ADPKD nationwide started on renal replacement therapy in 2014 and 2020.

RESULTS

Compared with new applications from 2015 to 2016, the prescription rates of antihypertensives and tolvaptan for the indicated patients at the 2017 renewal application increased by 2.0% (odds ratio = 1.41, p = 0.008) and 47.4% (odds ratio = 10.1, p > 0.001), respectively. These quality indicators improved with antihypertensive treatment, especially in patients with chronic kidney disease stages 1-2 (odds ratio = 1.79, p = 0.013) and in those aged < 50 years (odds ratio = 1.70, p = 0.003). The number of patients with ADPKD who were started on renal replacement therapy in Japan decreased from 999 in 2014 to 884 in 2020 in the nationwide database (odds ratio = 0.83, p < 0.001).

CONCLUSIONS

The Japanese public intractable disease support system contributes to improvement of ADPKD treatment.

Chapter 1: Evaluation of kidney function in patients undergoing anticancer drug therapy, from clinical practice guidelines for the management of kidney injury during anticancer drug therapy 2022

The prevalence of CKD may be higher in patients with cancer than in those without due to the addition of cancer-specific risk factors to those already present for CKD. In this review, we describe the evaluation of kidney function in patients undergoing anticancer drug therapy. When anticancer drug therapy is administered, kidney function is evaluated to (1) set the dose of renally excretable drugs, (2) detect kidney disease associated with the cancer and its treatment, and (3) obtain baseline values for long-term monitoring. Owing to some requirements for use in clinical practice, a GFR estimation method such as the Cockcroft-Gault, MDRD, CKD-EPI, and the Japanese Society of Nephrology's GFR estimation formula has been developed that is simple, inexpensive, and provides rapid results. However, an important clinical question is whether they can be used as a method of GFR evaluation in patients with cancer. When designing a drug dosing regimen in consideration of kidney function, it is important to make a comprehensive judgment, recognizing that there are limitations regardless of which estimation formula is used or if GFR is directly measured. Although CTCAEs are commonly used as criteria for evaluating kidney disease-related adverse events that occur during anticancer drug therapy, a specialized approach using KDIGO criteria or other criteria is required when nephrologists intervene in treatment. Each drug is associated with the different disorders related to the kidney. And various risk factors for kidney disease associated with each anticancer drug therapy.

Retrospective observational study of a novel smartphone app on the management of patients with mild cognitive impairment or mild dementia

Introduction

In this study, we aimed to evaluate the feasibility, utility, and potential effects of LQ-M/D App, a smartphone application developed by Life Quest Inc., Tokyo, Japan, for patients with mild cognitive impairment (MCI) and mild dementia. The app incorporates cognitive and physical exercise training, lifestyle habit acquisition features, and a continuity improvement feature added in the post-update version to enhance user engagement. The continuity improvement feature includes the optimization of training content, and disease education, and enables family monitoring via a family app.

Methods

A retrospective analysis was conducted on app usage, cognitive and exercise training implementation and interruptions, questionnaire response rates, and cognitive assessments in a single institution. A total of 20 patients used the app, with 10 patients using the pre-update version without the continuity improvement feature, and the other 10 patients using the post-update version with the continuity improvement feature.

Results and Conclusion

The results demonstrated that the LQ-M/D App could be effectively used by the study population, and the continuity improvement feature positively influenced app usage in several aspects. Although a potential association between app usage and cognitive ability was suggested, the scatter in the data points warrants cautious interpretation. Limitations of the study included a small sample size, a single institution setting, and the retrospective nature of the study. In the future, a randomized controlled trial design using a larger sample size and multiple institutions to further evaluate the effectiveness of LQ-M/D App in managing MCI and mild dementia should be performed.

Urine spermine and multiparametric magnetic resonance imaging for prediction of prostate cancer in Japanese men

Objectives

To investigate the role of urine spermine and spermine risk score in predicting prostate cancer (PCa) diagnoses in combination with multiparametric magnetic resonance imaging (mpMRI).

Methods

Three hundred forty seven consecutive men with elevated prostate-specific antigen (PSA) with mpMRI examination were prospectively enrolled in this study. In 265 patients with PSA levels between 4 and20 ng/ml, pre-biopsy urine samples were analyzed for spermine levels with ultra-high performance liquid chromatography (UPLC-MS/MS). Transperineal image-guided prostate biopsies with 16-18 cores were performed. Logistic regressions were used to form different models for the prediction of the PCa, and the performances were compared using the area under the curve (AUC).

Results

The median serum PSA level and prostate volume were 7.4 ng/mL and 33.9 mL, respectively. PCa and high-grade PCa (ISUP group ≥2, HGPCa) were diagnosed in 66.0% (175/265) and 132/265 (49.8%) cases, respectively. The urine spermine levels were significantly lower in men with PCa (0.87 vs. 2.20, P < 0.001). Multivariate analyses showed that age, PSA, PV, urine spermine level, and Prostate Imaging Reporting and Data System (PI-RADS) findings were independent predictors for PCa. The Spermine Risk Score is a multivariable model including PSA, age, prostate volume, and urine spermine. Adding the Spermine Risk Score to PI-RADS improved the AUC from 0.73 to 0.86 in PCa and from 0.72 to 0.83 in high grade PCa (HGPCa) prediction (both P < 0.001). At 90% sensitivity for HGPCa prediction using Spermine Risk Score, 31.1% of unnecessary biopsies could be avoided. In men with equivocal MRI PI-RADS score 3, the AUC for HGPCa prediction was 0.58, 0.79, and 0.87 for PSA, PSA density, and Spermine Risk Score, respectively.

Conclusion

Urine Spermine Risk Score, including mpMRI could accurately identify men at high risk of HGPCa and reduce unnecessary prostate biopsies. Spermine Risk Score could more accurately predict HGPCa than PSA density in men with MRI showing equivocal PI-RADS 3 lesions.

High prevalence of frailty in patients with lower urinary tract symptoms

AIM

Older adults are more likely to be frail and have a high prevalence of urological diseases such as lower urinary tract symptoms (LUTS). The purpose of this study was to clarify the prevalence and characteristics of comorbid frailty in older patients with urological diseases.

METHODS

We retrospectively reviewed the medical records of 970 patient who visited the Department of Urology, Juntendo University Hospital between October 2015 and October 2016. Patients were selected who were 65 years of age or older and were being evaluated by the Kihon Checklist (KCL) to assess frailty. We examined the prevalence of comorbid frailty in urological diseases, identified factors associated with comorbid frailty in urological diseases, and examined KCL scores in urological diseases with a high prevalence of frailty.

RESULTS

A total of 405 participants were included. Of these, 21.7% were frail, 20.5% were pre-frail, and 57.8% were robust. LUTS, overactive bladder, and neurogenic bladder showed a statistically significant relationship with comorbid frailty, with high frailty prevalence rates of 44/140 (31.4%), 19/36 (52.8%), and 4/6 (66.7%), respectively. Factors related to the comorbid frailty according to multivariate analysis were female sex (P = 0.001), older age (P < 0.001), and LUTS (P < 0.033). Of the KCL subscale scores, instrumental activities of daily living (P = 0.008), physical function (P < 0.001), oral function (P = 0.008), housebound (P = 0.009), and depression (P = 0.034) were higher in LUTS patients than in non-LUTS patients.

CONCLUSIONS

Among patients with urological diseases, those with LUTS were found to have a high prevalence of frailty. Geriatr Gerontol Int 2023; 23: 609-615.

PKD1 Mutation Is a Biomarker for Autosomal Dominant Polycystic Kidney Disease

BACKGROUND

Autosomal dominant polycystic kidney disease (ADPKD) occurs in 1 in 500-4000 people worldwide. Genetic mutation is a biomarker for predicting renal dysfunction in patients with ADPKD. In this study, we performed a genetic analysis of Japanese patients with ADPKD to investigate the prognostic utility of genetic mutations in predicting renal function outcomes.

METHODS

Patients clinically diagnosed with ADPKD underwent a panel genetic test for germline mutations in PKD1 and PKD2. This study was conducted with the approval of the Ethics Committee of Juntendo University (no. 2019107).

RESULTS

Of 436 patients, 366 (83.9%) had genetic mutations. Notably, patients with PKD1 mutation had a significantly decreased ΔeGFR/year compared to patients with PKD2 mutation, indicating a progression of renal dysfunction (-3.50 vs. -2.04 mL/min/1.73 m²/year, p = 0.066). Furthermore, PKD1 truncated mutations had a significantly decreased ΔeGFR/year compared to PKD1 non-truncated mutations in the population aged over 65 years (-6.56 vs. -2.16 mL/min/1.73 m²/year, p = 0.049). Multivariate analysis showed that PKD1 mutation was a more significant risk factor than PKD2 mutation (odds ratio, 1.81; 95% confidence interval, 1.11-3.16; p = 0.020).

CONCLUSIONS

The analysis of germline mutations can predict renal prognosis in Japanese patients with ADPKD, and PKD1 mutation is a biomarker of ADPKD.

Bone scan index (BSI) scoring by using bone scintigraphy and circulating tumor cells (CTCs): predictive factors for enzalutamide effectiveness in patients with castration-resistant prostate cancer and bone metastases

Reports of Bone Scan Index (BSI) calculations as imaging biomarkers to predict survival in patients with metastatic castration-resistant prostate cancer (mCRPC) have been mainly from retrospective studies. To evaluate the effectiveness of enzalutamide (ENZ) in Japanese patients with mCRPC and bone metastases using BSI (bone scintigraphy) and circulating tumor cell (CTC) analysis. Prospective, single-arm study at Juntendo University affiliated hospitals, Japan. Patients were administered 160 mg ENZ daily, with 3 monthly assessments: BSI, prostate specific antigen (PSA), CTC and androgen receptor splicing variant-7 (AR-V7) status. Primary endpoint: BSI-decreasing rate after ENZ treatment. Secondary endpoints: PSA-decreasing rate and progression free survival (PFS). Statistical analyses included the Wilcoxon t-test, Cox proportional hazard regression analysis, and log-rank test. Median observation period: 17.9 months, and median PFS: 13.8 (2.0-43.9) months (n = 90 patients). A decrease in BSI compared to baseline as best BSI change on ENZ treatment was evident in 69% patients at the end of the observation period (29% patients showed a complete response, BSI 0.00). At 3 months 67% patients showed a ≥ 50% PSA reduction, and 70% after ENZ treatment. PSA decline (3 months) significantly associated with a prolonged median PFS: 18.0 (estimated) versus 6.4 months (HR 2.977 [95% CI 1.53-5.78], p = 0.001). Best BSI decline response significantly associated with a prolonged PFS: 18.1(estimated) versus 7.8 months (HR 2.045 [95% CI: 1.07-3.90], p = 0.029). CTC negative status (n = 20) significantly associated with a prolonged PFS: 13.4 [estimated] vs 8.6 months (HR 2.366, 95% CI 0.97-5.71, p = 0.041). CTC positive/AR-V7 positive status significantly associated with a shorter PFS: 5.9 months (HR 8.56, 95% CI 2.40-30.43, p = 0.0087). -reduction (3 months) and BSI-reduction (on ENZ treatment) were significant response biomarkers, and a negative CTC status was a predictive factor for ENZ efficacy in patients with mCRPC.

Cystic Kidney Diseases That Require a Differential Diagnosis from Autosomal Dominant Polycystic Kidney Disease (ADPKD)

Autosomal dominant polycystic kidney disease (ADPKD) is the most common hereditary cystic kidney disease, with patients often having a positive family history that is characterized by a similar phenotype. However, in atypical cases, particularly those in which family history is unclear, a differential diagnosis between ADPKD and other cystic kidney diseases is important. When diagnosing ADPKD, cystic kidney diseases that can easily be excluded using clinical information include: multiple simple renal cysts, acquired cystic kidney disease (ACKD), multilocular renal cyst/multilocular cystic nephroma/polycystic nephroma, multicystic kidney/multicystic dysplastic kidney (MCDK), and unilateral renal cystic disease (URCD). However, there are other cystic kidney diseases that usually require genetic testing, or another means of supplementing clinical information to enable a differential diagnosis of ADPKD. These include autosomal recessive polycystic kidney disease (ARPKD), autosomal dominant tubulointerstitial kidney disease (ADTKD), nephronophthisis (NPH), oral-facial-digital (OFD) syndrome type 1, and neoplastic cystic kidney disease, such as tuberous sclerosis (TSC) and Von Hippel-Lindau (VHL) syndrome. To help physicians evaluate cystic kidney diseases, this article provides a review of cystic kidney diseases for which a differential diagnosis is required for ADPKD.

P-138 Transcriptomic signatures in trophectoderm and inner cell mass of human blastocysts with expected pregnancy rates

Study question

Is it possible to identify the molecular factors that contribute to the implantation potential of blastocysts?

Summary answer

Genes correlated with expected pregnancy rate in trophectoderm (TE) and inner cell mass (ICM) respectively were identified, and aneuploidy alone couldn’t predict the pregnancy expectation.

What is known already

The selection of suitable embryos for transfer is critical for achieving successful pregnancy outcomes in assisted reproductive technology (ART). Although pre-implantation genetic testing for aneuploidy (PGT-A) as well as morphological and chronological evaluation of embryos, have been conducted in clinical practice, they do not fully guarantee successful pregnancy. Recently, transcriptional events in early human embryonic development have been analyzed using RNA-sequencing (RNA-seq) and researchers are attempting to apply this information to ART.

Study design, size, duration

To determine the correlation between blastocyst evaluation and pregnancy rate, we retrospectively analyzed 1,890 cases underwent frozen-thawed blastocyst transfer from March 2018 to December 2020. A total of 13 blastocysts that were cryopreserved for clinical use between February 2011 and September 2018, then scheduled for disposal and with consented for research, were subjected to RNA-seq without distinguishing between conventional in vitro fertilization (c-IVF) and intracytoplasmic sperm injection (ICSI).

Participants/materials, setting, methods

Blastocysts were donated by infertile couples undergoing c-IVF or ICSI cycles at the Yamashita Shonan Yume Clinic with informed consent under ethical approval. TE and ICM cells were collected from blastocysts by using a micromanipulator and then subjected to RNA-seq. Gene expression analysis and digital karyotyping using RNA-seq were performed simultaneously for TE and ICM cells, respectively. One-way analysis of variance, chi-square test and Tukey's multiple comparison test were used for this study.

Main results and the role of chance

Blastocysts were classified into three groups to correlate with pregnancy rates based on the diameter of the blastocyst and the time to reach this size: those taking less than 130 h to reach a diameter of &gt; 170 μm (Group 1, n = 676), those taking more than 140 h to reach a diameter of &lt; 180 μm (Group 2, n = 158), and the rest (Group 3, n = 1,056). The pregnancy rates of Groups 1, 2 and 3 were 59.0%, 16.5%, and 34.2%, respectively (p &lt; 0.01). Assessing the differences in overall transcripts correlated between Group 1 (n = 5), Group 2 (n = 4), and Group 3 (n = 4), 26 and 67 differentially expressed genes (DEGs) were identified in ICM and TE cells, respectively. Importantly, downregulated genes in TE of blastocysts with lower expectation of pregnancy included tight junction-related genes, such as CXADR, CLDN10, and ATP1B1, which were implicated in peri-implantation development. Digital karyotyping revealed karyotypic abnormalities and mosaicism in all groups with no common abnormalities observed, suggesting that aneuploidy alone cannot predict the pregnancy expectation.

Limitations, reasons for caution

Although 93 genes potentially related to implantation have been identified, it is still unclear how these genes are involved in implantation. In vitro implantation models using human embryos and artificial embryos currently under development are expected to contribute to the elucidation of the functions of these genes.

Wider implications of the findings

Our results provide reliable candidates for genes that could allow for non-invasive selection of high-quality blastocysts for ART and add to the knowledge base of transcriptional events in human peri-implantation development.

Trial registration number

not applicable

P-198 An analysis of the size of micro pronucleus in 2.1 pronuclear zygotes by using time-lapse images

Study question

Is it possible to determine the difference between 2.1 pronuclear (2.1PN) zygotes and tripronuclear (3PN) zygotes from time-lapse images?

Summary answer

A pronucleus of less than 15 μm in diameter can be considered the micro pronucleus (micro PN), and it is possible to classify 2.1PN zygotes.

What is known already

2.1PN zygotes are defined as zygotes with two pronuclei and one smaller pronucleus. Capalbo et al.  (2017) reported that most of the 2.1PN-derived blastocysts were diploid by preimplantation genetic testing for aneuploidy (PGT-A), including single-nucleotide polymorphisms (SNPs) analysis. Thus, the treatment with 2.1 PN zygotes should be performed with chromosome testing. In Japan, where PGT-A is not available in principle, 2.1PN zygotes are rarely used in the embryo transfer. On the other hand, the size of the micro pronucleus in 2.1PN zygotes has not been clearly defined, and it is difficult to determine differences between 2.1PN and 3PN zygotes.

Study design, size, duration

The study was performed retrospectively on 2463 cycles of in vitro fertilization (IVF) conducted at our clinic between August 2020 and December 2021. A total of 3073 embryos underwent conventional-IVF (c-IVF) or intracytoplasmic sperm injection (ICSI) and were cultured in the time-lapse incubator, of which 221 zygotes with three pronuclei were used in the study.

Participants/materials, setting, methods

The diameter of the three PNs at one hour before syngamy from time-lapse images; 2.1 PN and 3PN zygotes were classified in the report by Capalbo et al. (2017). The age of the patients and the method of insemination between the groups were compared, and the diameter of the micro PN was analysed. Moreover, logistic regression analysis was performed to investigate the predictor of 2.1PN zygotes from the morphological characteristics of oocytes at ICSI.

Main results and the role of chance

The mean age of each patient was 42.9 years for 2.1PN zygotes and 39.8 years for 3PN zygotes, significantly higher for 2.1PN zygotes (P =0.003). On the other hand, when comparing the stage of oocyte maturation at the time of oocyte retrieval, there was no significant difference (P =0.749). According to the insemination method, the incidence of 2.1PN zygotes was significantly higher in ICSI (including rescue-ICSI) compared to c-IVF: 32.9% [95%CI: 22.5-44.6%] vs 2.4% [95%CI: 0.1-12.9%] (P &lt;0.001). In terms of ICSI-derived zygotes, the mean age was also significantly higher for 2.1PN zygotes compared to 3PN zygotes: 43.3 years vs. 40.9 years (P =0.03). The diameter of micro PNs calculated using the receiver operating characteristics (ROC) curve from the measurements of the diameter was less than 15 μm (AUC [95%CI]: AUC=0.988 [0.975-1.00]). Logistic regression analysis using age, position of the oocyte spindle at ICSI, cytoplasmic viscosity, and condition of the cell membrane as explanatory variables revealed a significant difference only in age (P =0.0154, odds ratio [95%CI]: 1.18 [1.03-1.35]) and no statistically significant oocyte morphological characteristics.

Limitations, reasons for caution

In this study, we have not investigated whether 2.1 PN zygotes become blastocysts. It will be necessary to further examine the criteria for 2.1PN along with chromosome testing to investigate the use of 2.1PN-derived blastocysts.

Wider implications of the findings

A pronucleus of less than 15 μm in diameter can be considered a micro PN. Compared to 3PN zygotes, 2.1PN zygotes were more frequently observed in older patients and in ICSI-derived zygotes. However, it is difficult to predict the incidence of 2.1PN zygotes from the oocytes’ morphological characteristics at ICSI.

Trial registration number

not applicable

Gut environment changes due to androgen deprivation therapy in patients with prostate cancer

BACKGROUND

It is estimated that by 2040 there will be 1,017,712 new cases of prostate cancer worldwide. Androgen deprivation therapy (ADT) is widely used as a treatment option for all disease stages. ADT, and the resulting decline in androgen levels, may indirectly affect gut microbiota. Factors affecting gut microbiota are wide-ranging; however, literature is scarce on the effects of ADT on gut microbiota and metabolome profiles in patients with prostate cancer.

METHODS

To study the changes of gut microbiome by ADT, this 24-week observational study investigated the relationship between testosterone levels and changes in gut microbiota in Japanese patients with prostate cancer undergoing ADT. Sequential faecal samples were collected 1 and 2 weeks before ADT, and 1, 4, 12, and 24 weeks after ADT. Blood samples were collected at almost the same times. Bacterial 16 S rRNA gene-based microbiome analyses and capillary electrophoresis-time-of-flight mass spectrometry-based metabolome analyses were performed.

RESULTS

In total, 23 patients completed the study. The α- and ß-diversity of gut microbiota decreased significantly at 24 weeks after ADT (p = 0.017, p < 0.001, respectively). Relative abundances of Proteobacteria, Gammaproteobacteria, Pseudomonadales, Pseudomonas, and concentrations of urea, lactate, butyrate, 2-hydroxyisobutyrate and S-adenosylmethionine changed significantly after ADT (p < 0.05). There was a significant positive correlation between the abundance of Proteobacteria, a known indicator of dysbiosis, and the concentration of lactate (R = 0.49, p < 0.01).

CONCLUSIONS

The decline in testosterone levels resulted in detrimental changes in gut microbiota. This dysbiosis may contribute to an increase in frailty and an increased risk of adverse outcomes in patients with prostate cancer.

O-154 First mitotic spindle formation led by sperm centrosome-dependent microtubule organising centres may cause high incidence of zygotic division errors in humans

Study question

Why do multinucleated blastomeres appear at high frequency in two-cell-stage embryos in humans?

Summary answer

Failure in microtubule assembly during the first mitotic spindle body formation by sperm centrosome-dependent microtubule organising centres (MTOCs) may lead to chromosomal instability.

What is known already

Unlike that in mice, multinucleated blastomeres appear at high frequency in two-cell-stage embryos in humans. However, the underlying mechanism remains elusive. In mice, multiple acentriolar MTOCs appear around the male and female pronuclei after pronuclear disappearance and contribute to dual-spindle formation, engulfing each parental chromosome. This spindle formation may ensure an error-free division, keeping the chromosomes stable during the first cleavage, as observed in mice, but it is unclear whether a similar mechanism exists in humans.

Study design, size, duration

To examine how sperm centrosomes contribute to MTOC formation in humans, two types of 3PN zygotes derived fromeither conventional in vitro fertilization (c-IVF, n = 30) or intracytoplasmic sperm injection (ICSI, n = 10) were used. The zygotes were collected from October 2018 to January 2020. MTOC and mitotic spindle formation at consecutive stages of development during the first cleavage were analysed under static and dynamic conditions using immunofluorescence assay and fluorescent live-cell imaging.

Participants/materials, setting, methods

Under ethics approval, 3PN zygotes were donated by infertile couples undergoing c-IVF or ICSI cycles at the Yamashita Shonan Yume Clinic in Japan. All participants provided informed consent. Immunofluorescence assay was performed using antibodies against α-tubulin, pericentrin, and H3K9me3 after fixation with MTSB-XF solution. Fluorescent live-cell imaging was performed using TagGFP2-H2B mRNA (chromosome marker) and FusionRed-MAP4 mRNA (microtubule marker).

Main results and the role of chance

Immunofluorescence revealed that while 3PN zygotes derived from c-IVF showed four pericentrin dots, those derived from ICSI exhibited two pericentrin dots. In pro-metaphase, an independent group of chromosomes derived from each pronucleus and MTOCs were formed by the sperm centrosome at the core. Microtubules from each MTOC extended toward the chromosomes in the early metaphase; a quadrupolar spindle was formed in the c-IVF-derived zygotes, and a bipolar spindle was formed in the ICSI-derived zygotes by the MTOCs at the zygote apex after chromosome alignment. In pro-metaphase, the microtubules extended from the MTOCs to the nearest chromosome. Since microtubule assembly was found on oocyte-derived chromosomes, we hypothesised that whether a chromosome is surrounded by microtubules depends on the location of the MTOCs, irrespective of its origin. Live-cell imaging of histone H2B and MAP4 revealed that four MTOCs appeared around the three pronuclei just before the disappearance of the pronuclear membrane; microtubules then extended from the MTOCs toward the chromosomes, beginning to form a mitotic spindle as the chromosomes moved to the centre of the oocyte. Interestingly, one of the three assembled chromosome groups showed no microtubule assembly in the pro-metaphase. Similar results were obtained in all six 3PN zygotes subjected.

Limitations, reasons for caution

We demonstrated the high risk of developing bare chromosomes not surrounded by microtubules during the formation of the first mitotic spindle, using human tripronuclear zygotes. However, owing to unavailability of normal fertilized oocytes for this study because of the clinical use, we were unable to confirm this in normal zygotes.

Wider implications of the findings

Although two sperm centrosome-dependent MTOCs are expected to be formed in normal fertilized oocytes, these MTOCs are not sufficient to completely enclose physically separated female and male chromosomes with the microtubules. This explains the high frequency of zygotic division errors that lead to unstable human chromosomes.

Trial registration number

not applicable

P–248 Statistical estimation for incidence of blastocyst trophectoderm vesicles (TVs) and efficacy of assisted hatching (AH)

Study question

The aim of this study is to analyse the association between blastocyst diameter and TVs development, and to examine the efficacy of AH.

Summary answer

Blastocysts with a diameter of more than 170 μm leads to high incidence of TVs and AH applied from the incidence should be effective.

What is known already

TVs are protrusion of trophectoderm cells often observed in expanding blastocyst stages. TVs can be observed in expanding blastocysts regardless of Intracytoplasmic sperm injection (ICSI) and Conventional-IVF (C-IVF), when the internal pressure of blastocysts increase. The rate of TVs incidence in blastocysts inseminated by ICSI is higher than that by C-IVF, due to penetration of the needle into the zona pellucida. Moreover, it has been reported that TVs may inhibit blastocyst hatching. However, the developmental timing of TVs is still unclear, and there is no study that has analysed the association between blastocyst diameter and the incidence of TVs.

Study design, size, duration

1) Diameters and TVs incidence of blastocysts by ICSI and C-IVF were measured, and the cut-off value and the area under the curve (AUC) of the receiver operating characteristic (ROC) curve were calculated to estimate the timing of TV incidence. 2) We analysed the clinical pregnancy rates of blastocysts with TVs treated by AH compared to those of blastocysts by C-IVF not subjected to AH.

Participants/materials, setting, methods

This study included 821 transferred frozen blastocysts ranging from March 2018 to November 2019. The embryos were cultured in a dry incubator after insemination by ICSI or C-IVF. Blastocyst freezing conditions were set at day5 to day7 with a diameter of more than 150 μm in inner diameter of zona pellucida, and this was measured before freezing. The ROC curve was performed using EZR statistical analysis software.

Main results and the role of chance

1) The incidence of TVs in blastocysts by ICSI and C-IVF was 27.5% (117/424) and 14.6% (58/397) respectively. The rate of the incidence of TVs in blastocysts inseminated by ICSI and C-IVF; 8.6% (12/140) and 0.95% (1/105) in 150–159 μm, 12.7% (14/110) and 8.2% (6/73) in 160–169 μm, 40.6% (28/69) and 10.5% (6/57) in 170–179 μm, 55.6% (30/54) and 25.5% (13/51) in 180–189 μm, 66.7% (20/30) and 35.7% (10/28) in 190–199 μm, and 68.4% (13/19) and 26.8% (22/82) in the diameter of more than 200 μm. The cut-off value of the ROC curve was respectively 170 μm (sensitivity 78.6% and specificity 73.0%) and 176 μm (sensitivity 84.5% and specificity 59.6%) in the diameter; the AUC was 0.8 [95%CI:0.752–0.848] and 0.74 [95%CI:0.687–0.793] respectively. 2) The clinical pregnancy rate of TVs blastocyst vs C-IVF blastocyst was 52.7% (88/167) vs 57.8% (37/64) respectively. There is no significant difference between the two clinical pregnancy rates (P = 0.556).

Limitations, reasons for caution

The findings of this study have to be seen in light of some limitations. Since this study aimed to analyse the incidence of TVs based on blastocyst size, we did not take into account the grade according to the Gardner classification and the number of trophectoderm cells.

Wider implications of the findings: Blastocysts inseminated by ICSI and C-IVF were highly likely to have TVs above 170 μm and 176 μm respectively. The clinical pregnancy rates of the blastocyst with TV treated by AH was similar to those of the C-IVF blastocyst.

Trial registration number

Not applicable

Preservation of kidney function irrelevant of total kidney volume growth rate with tolvaptan treatment in patients with autosomal dominant polycystic kidney disease

Background

Tolvaptan slowed the rates of total kidney volume (TKV) growth and renal function decline over a 3-year period in patients with autosomal dominant polycystic kidney disease (ADPKD) enrolled in the Tolvaptan Efficacy and Safety in Management of Autosomal Dominant Polycystic Kidney Disease and Its Outcomes (TEMPO) 3:4 trial (NCT00428948). In this post hoc analysis of Japanese patients from TEMPO 3:4, we evaluated whether the effects of tolvaptan on TKV and on renal function are interrelated.

Methods

One hundred and forty-seven Japanese patients from TEMPO 3:4 were included in this analysis (placebo, n = 55; tolvaptan, n = 92). Tolvaptan-treated patients were stratified into the responder group (n = 37), defined as tolvaptan-treated patients with a net decrease in TKV from baseline to year 3, and the non-responder group (n = 55), defined as tolvaptan-treated patients with a net increase in TKV.

Results

Mean changes during follow-up in the placebo, responder, and non-responder groups were 16.99%, − 8.33%, and 13.95%, respectively, for TKV and − 12.61, − 8.47, and − 8.58 mL/min/1.73 m², respectively, for estimated glomerular filtration rate (eGFR). Compared with the placebo group, eGFR decline was significantly slowed in both the responder and non-responder groups (P < 0.05).

Conclusion

Tolvaptan was effective in slowing eGFR decline, regardless of TKV response, over 3 years in patients with ADPKD in Japan. Treatment with tolvaptan may have beneficial effects on slowing of renal function decline even in patients who have not experienced a reduction in the rate of TKV growth by treatment with tolvaptan.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10157-020-02009-0.

Imaging Identification of Rapidly Progressing Autosomal Dominant Polycystic Kidney Disease: Simple Eligibility Criterion for Tolvaptan

BACKGROUND

Tolvaptan was approved for the treatment of autosomal dominant polycystic kidney disease (ADPKD). However, the official indication of "rapidly progressive disease" is described differently in the clinical guidelines. We aim to define "rapidly progressive disease" by risk of ESRD, which is evaluated using estimated height-adjusted total kidney volume (HtTKV) growth rate.

METHODS

The risk of ESRD was retrospectively analyzed in 617 initially non-ESRD adults with ADPKD and observed with standard of care between 2007 and 2018. The estimated annual growth rate of the HtTKV, termed as eHTKV-α (%/year), is derived from the following equation: [HtTKV at age t] = K(1 + eHTKV-α/100)t, where K = 150 mL/m is used in Mayo Imaging Classification and K = 130 mL/m is proposed for individually stable eHTKV-α value from baseline. The accuracy of eHTKV-α to predict ESRD for censored ages was analyzed using time-dependent receiver-operating characteristic curves (ROC). The cutoff point of initially measured eHTKV-α to predict ESRD was assessed using Kaplan-Meier and Cox's proportional hazards models. Performance characteristics of the cutoff point for censored ages were calculated using time-dependent ROC and validated by the bootstrap method.

RESULTS

The area under the time-dependent ROC of eHTKV-α to predict ESRD at age 65 was 0.89 ± 0.04 (K = 130). The mean renal survival was less than 70 years at eHTKV-α ≥4.0%/year (K = 130). Mean renal survival was approximately 12 years shorter, and hazard ratio of ESRD was more than 5-time higher at this cutoff point than at lower point. Time-dependent sensitivity for age 65 and cutoff point of 4.0%/year (K = 130) was 93.4 ± 0.3%. Between cutoff points ≥4.0%/year (K = 130) and ≥3.5%/year (K = 150), there was no significant difference in performance characteristics and accuracy to predict ESRD.

CONCLUSION

eHTKV-α well predicts ESRD. Initially, measured eHTKV-α ≥4.0%/year (K = 130) defines high-risk ESRD. Without additional conditions, a single eHTKV-α cutoff point identifies subjects that are most likely to benefit from tolvaptan.

P6405Potential for drug-drug interaction between vonoprazan and prasugrel on antiplatelet effect assessed by VerifyNow P2Y12 assay in patients with coronary artery disease

Background

Vonoprazan is a potassium-competitive acid blocker increasingly used in Japan to prevent gastrointestinal bleeding in patients under dual antiplatelet therapy (DAPT) after coronary stents implantation. Since cytochrome P450 (CYP) 3A4 is involved in the primary metabolism of vonoprazan and prasugurel, there is a possibility that CYP-mediated drug-drug interaction between them can attenuate the antiplatelet function of prasugrel.

Purpose

The aim of this study was to investigate whether antiplatelet effect of prasugrel could be attenuated upon coadministration with vonoprazan compared to conventional proton pump inhibitors (PPIs).

Method

We evaluated 72 patients (57 males, 67±11 years) with coronary artery disease who were taking either vonoprazan (n=35) or PPIs (n=37) in combination with DAPT (aspirin and prasugrel) after drug-eluting stents implantation. PPIs included 21 esomeprazole, 8 lansoprazole, and 8 rabeprazole. Antiplatelet effects of prasugrel were assessed using VerifyNow P2Y12 assay. Primary measurements were P2Y12 reaction units (PRU) and P2Y12 percent inhibition. High on-treatment platelet reactivity (HPR) on prasugrel was defined as PRU >208. Administration period of vonoprazan or PPIs in combination with DAPT ≤7 days was defined as early administration period.

Results

Median administration period of vonoprazan or PPIs in combination with DAPT was 127 days. There were no significant differences in baseline clinical characteristics between patients with vonoprazan and PPIs. In the analysis for all subjects, patients with vonoprazan showed similar PRU (166±50 vs. 167±64, p=0.93) and percent inhibition (36±18 vs. 38±23, p=0.66) compared to those with PPIs. No significant differences were observed in the prevalence of HPR between patients with vonoprazan and PPIs (17 vs. 30%, p=0.27). In the analysis for patients in early administration period [vonoprazan (n=14) vs. PPIs (n=10)], there were no significant differences in PRU (166±47 vs. 186±82, p=0.45), percent inhibition (33±17 vs. 30±26, p=0.73), and prevalence of HPR (14 vs. 50%, p=0.085) between patients with vonoprazan and PPIs. In addition, the analysis for patients over early administration period [vonoprazan (n=21) vs. PPIs (n=27)] showed that PRU (166±55 vs. 160±57, p=0.73), percent inhibition (37±19 vs. 41±21, p=0.57), and prevalence of HPR (19 vs. 22%, p=1.00) were comparable between patients with vonoprazan and PPIs.

Conclusion

Compared to PPIs, vonoprazan did not exhibit significant inhibitory effects on the antiplatelet activity of prasugrel assessed by VerifyNow assay. These findings suggest that there are possibly no clinically harmful drug-drug interactions between vonoprazan and prasugrel.

P1549Serum soluble Klotho is associated with extent of coronary artery calcification in patients with stable angina pectoris undergoing percutaneous coronary intervention

Background

Klotho, which was originally identified as an aging suppressor, is a key regulator of bone and mineral metabolism. Transmembrane and soluble forms of Klotho protein have been identified. The transmembrane form serves as an obligate co-receptor for fibroblast growth factor 23 (FGF23). However, the physiological importance of soluble form of Klotho has not been determined.

Purpose

The present study aimed to test the hypothesis that circulating soluble Klotho levels can predict the presence or extent of coronary artery calcification (CAC) in patients with coronary artery disease.

Methods

We analyzed CAC of culprit lesions in patients with 75 stable angina pectoris who were not on dialysis and were scheduled for percutaneous coronary intervention (PCI) following intravascular ultrasound (IVUS). Arc and length of each calcium within the culprit lesion was measured by IVUS. The main outcome measure was the calcium index; a volumetric IVUS-derived measure which was calculated as total calcium length/lesion length × maximal calcium arc/360°. Low calcium index was defined as calcium index <0.042 of the first quartile value. Serum Klotho and FGF23 were measured before PCI. Patients were divided into two groups according to median serum Klotho value: low-Klotho (n=37, ≤460 pg/mL) and high-Klotho group (n=38, >460 pg/mL).

Results

Compared with patients with low-Klotho, those with high-Klotho had higher estimated glomerular filtration rate (eGFR) (69±20 vs. 55±16 mL/min/1.73 m2, p<0.001), lower FGF23 levels (51±24 vs. 67±41 pg/mL, p=0.010). Patients with high-Klotho had significantly lower calcium index than those with low-Klotho (0.17±0.21 vs. 0.24±0.23, p=0.043). Serum Klotho levels correlated significantly and inversely with calcium index (r=−0.31, p=0.006). The correlation between Klotho and calcium index was pronounced at analysis in patients with eGFR <60 mL/min/1.73 m2 (r=−0.52, p<0.001). Logistic regression analysis showed that high-Klotho is a sole significant independent factor associated with low calcium index (odds ratio 7.17, p=0.004). Presence of high-Klotho had high sensitivity and negative predictive value for identifying low calcium index (83% and 92%, respectively).

Conclusions

Serum Klotho values were independently and inversely associated with the degree of CAC assessed by IVUS. These findings have important clinical implications for serum Klotho as a biomarker that reflects the extent of CAC.