Psoas Muscle Volume Is a Predictive Marker of Fatigue and Anorexia in Prostate Cancer Patients Treated with Enzalutamide.

Introduction: Enzalutamide is approved for the treatment of patients with metastatic castration-resistant prostate cancer. Adverse effects (e.g., fatigue and anorexia) are often observed and cause difficulty with continuous therapy; however, no clinical data describing which patients are more likely to suffer adverse effects were observed. Therefore, this study hypothesized that body composition, comprising body fat distribution and psoas muscle volume, may affect the occurrence of subjective symptoms (e.g., fatigue and anorexia) in prostate cancer patients treated with enzalutamide. Methods: Adverse effects, especially fatigue, anorexia, insomnia, and pain, were retrospectively evaluated by CTCAE v4.0 criteria. Sixty-seven prostate cancer patients treated with enzalutamide were enrolled, and body fat, visceral fat percentage, and psoas muscle ratio (psoas muscle, in cubic centimeter/height, in meters) were calculated using computed tomography images evaluated before enzalutamide, with SYNAPSE VINCENT software. Univariate analysis was performed to identify the factors associated with adverse effects. Results: Univariate analysis showed that high psoas muscle ratio was significantly associated with fatigue (grade ≥ 2; odds ratio, 3.875; 95% confidence interval, 1.016-17.134; P = 0.047), but inversely related to anorexia (grade ≥ 2; odds ratio, 0.093; 95% confidence interval, 0.011-0.784; P = 0.029). Conclusions: Psoas muscle ratio is a predictive marker of fatigue and anorexia in patients treated with enzalutamide.

Testosterone level in seminal vesicle fluid is a better indicator of erectile function than serum testosterone in patients with prostate cancer.

OBJECTIVES: Semen comprises prostatic fluid and seminal vesicle fluid, and seminal vesicle fluid contains various factors such as prostaglandin E2 (PGE2), zinc, and testosterone, which play important roles in sperm motility. It is not known whether these factors affect erectile function. In this study, we investigated factors in seminal vesicle fluid that may affect erectile function. METHODS: After receiving institutional review board approval, we collected seminal vesicle fluid samples from 134 Japanese patients with localized prostate cancer who underwent robot-assisted radical prostatectomy. We examined the relationship between the results of the Sexual Health Inventory for Men (SHIM), erection hardness score, an original questionnaire on the presence or absence of sexual desire, and concentrations of several factors in seminal vesicle fluid (testosterone, PGE2, transforming growth factor ß1, and 8-hydroxy-2-deoxyguanosine), as well as the serum testosterone level. RESULTS: Median participant age was 67 (range 51-77) years. Median concentrations were as follows: seminal vesicle testosterone 1.85 (range 0.17-4.32) ng/ml and serum testosterone 4.60 (range 1.75-10.82) ng/ml. When the SHIM score was divided into two groups, seminal vesicle testosterone concentration was significantly increased (p = 0.002) in participants with a SHIM score ≥17, and no significant difference was observed in serum testosterone levels (p = 0.661). Multivariate analysis revealed that seminal vesicle testosterone was significantly correlated with the SHIM score (≥17 vs. <17; odds ratio 2.137, 95% confidence interval 1.148-3.978, p = 0.016). CONCLUSIONS: Testosterone levels in seminal vesicle fluid can reflect erectile function in patients with prostate cancer, suggesting that seminal vesicle testosterone is very important for male erectile function.

Anticancer Effect of Second-line Treatment for Castration-Resistant Prostate Cancer Following First-line Treatment with Androgen Receptor Pathway Inhibitors.

INTRODUCTION: Studies on the effect of androgen receptor pathway inhibitors (ARPI), docetaxel (DTX), and radium-223 (Ra-223) after first-line treatment with ARPI in patients with castration-resistant prostate cancer (CRPC) are scarce. This study compared the efficacy of treatment after ARPI for CRPC. METHODS: Patients with CRPC who received ARPI as first-line treatment and different second-line treatments were retrospectively reviewed. Clinicopathological backgrounds and treatment outcomes, including maximum prostate-specific antigen (PSA) decrease, progression-free survival (PFS), and overall survival (OS), were compared between second-line treatments. RESULTS: In total, 88 patients were enrolled. Forty-one (46.6%), 37 (42.0%), and 10 (11.4%) patients were treated with ARPI, DTX, and Ra-223, respectively. Patients whose PSA levels were not adequately reduced by first-line treatment with ARPI were eventually enrolled in the DTX treatment (P = 0.030). PSA decrease was not significantly different when comparing treatments. PFS in the DTX group was significantly better than in the other two groups (P = 0.023). In multivariate analysis, DTX was an independent prognostic factor for better PFS compared to ARPI (hazard ratio, 95% confidence interval; 0.44, 0.25-0.79, P = 0.006). Subgroup analysis showed a favorable impact of DTX on PFS in patients with Gleason score >8 (interaction P = 0.027) and a PSA decline >50% (interaction P = 0.019) during first-line treatment with ARPI. However, no significant difference in OS was observed between groups of different second-line treatments. CONCLUSIONS: This study suggests that in patients with CRPC, second-line treatment with DTX following progression in patients who received ARPI as first-line treatment is more beneficial compared with second-line treatment with ARPI or Ra-233.

Molecular detection of maturation stages in the developing kidney.

Recent advances in stem cell biology have enabled the generation of kidney organoids in vitro, and further maturation of these organoids is observed after experimental transplantation. However, the current organoids remain immature and their precise maturation stages are difficult to determine because of limited information on developmental stage-dependent gene expressions in the kidney in vivo. To establish relevant molecular coordinates, we performed single-cell RNA sequencing (scRNA-seq) on developing kidneys at different stages in the mouse. By selecting genes that exhibited upregulation at birth compared with embryonic day 15.5 as well as cell lineage-specific expression, we generated gene lists correlated with developmental stages in individual cell lineages. Application of these lists to transplanted embryonic kidneys revealed that most cell types, other than the collecting ducts, exhibited similar maturation to kidneys at the neonatal stage in vivo, revealing non-synchronous maturation across the cell lineages. Thus, our scRNA-seq data can serve as useful molecular coordinates to assess the maturation of developing kidneys and eventually of kidney organoids.

Activin Is Superior to BMP7 for Efficient Maintenance of Human iPSC-Derived Nephron Progenitors.

Kidney formation is regulated by the balance between maintenance and differentiation of nephron progenitor cells (NPCs). Now that directed differentiation of NPCs from human induced pluripotent stem cells (iPSCs) can be achieved, maintenance and propagation of NPCs in vitro should be beneficial for regenerative medicine. Although WNT and FGF signals were previously shown to be essential for NPC propagation, the requirement for BMP/TGFß signaling remains controversial. Here we reveal that activin has superior effects to BMP7 on maintenance efficiency of human iPSC-derived NPCs. Activin expanded ITGA8+/PDGFRA-/SIX2-GFP+ NPCs by 5-fold per week at 80%-90% efficiency, and the propagated cells possessed robust capacity for nephron formation both in vitro and in vivo. The expanded cells also maintained their nephron-forming potential after freezing. Furthermore, the protocol was applicable to multiple non-GFP-tagged iPSC lines. Thus, our activin-based protocol will be applicable to a variety of research fields including disease modeling and drug screening.

Reconstitution of the embryonic kidney identifies a donor cell contribution to the renal vasculature upon transplantation.

The kidney possesses a highly organised vasculature that is required for its filtration function. While recent advances in stem cell biology have enabled the in vitro generation of kidney tissues, at least partially, recapitulation of the complicated vascular architecture remains a huge challenge. Herein we develop a method to reconstitute both the kidney and its vascular architecture in vitro, using dissociated and sorted mouse embryonic kidney cells. Upon transplantation, arteriolar networks were re-established that ran through the interstitial space between branching ureteric buds and eventually entered glomeruli. Using this system, we found that donor-derived endothelial cells significantly contributed to the arterioles and glomerular capillaries formed after transplantation. Unexpectedly, the near-complete depletion of canonical endothelial cells from the donor embryonic kidney suggested the existence of unidentified donor-derived endothelial precursors that were negative for canonical endothelial markers, but still contributed significantly to the vasculature in the transplants. Thus, our protocol will serve as a useful platform for identification of renal endothelial precursors and induction of these precursors from pluripotent stem cells.

From organoids to transplantable artificial kidneys.

It is difficult to restore kidney function following chronic kidney damage. Although dialysis is currently used to treat patients with chronic kidney disease, it does not cure the disease, while severely restricting the patient's daily and social activities. Kidney transplantation is an alternative and curative therapy, but donor numbers remain limited. However, the generation of kidney organoids from human induced pluripotent stem cells represents an important recent advance in regenerative medicine. Kidney organoids are expected to be used for disease modeling and drug discovery, and may eventually be applicable for transplantation. In this review, we describe the current status of kidney organoids and discuss the hurdles that need to be overcome to generate transplantable artificial kidneys.

Organoids from Nephrotic Disease-Derived iPSCs Identify Impaired NEPHRIN Localization and Slit Diaphragm Formation in Kidney Podocytes.

Mutations in the NPHS1 gene, which encodes NEPHRIN, cause congenital nephrotic syndrome, resulting from impaired slit diaphragm (SD) formation in glomerular podocytes. However, methods for SD reconstitution have been unavailable, thereby limiting studies in the field. In the present study, we established human induced pluripotent stem cells (iPSCs) from a patient with an NPHS1 missense mutation, and reproduced the SD formation process using iPSC-derived kidney organoids. The mutant NEPHRIN failed to become localized on the cell surface for pre-SD domain formation in the induced podocytes. Upon transplantation, the mutant podocytes developed foot processes, but exhibited impaired SD formation. Genetic correction of the single amino acid mutation restored NEPHRIN localization and phosphorylation, colocalization of other SD-associated proteins, and SD formation. Thus, these kidney organoids from patient-derived iPSCs identified SD abnormalities in the podocytes at the initial phase of congenital nephrotic disease.