SNX9 Inhibits Cell Proliferation and Cyst Development in Autosomal Dominant Polycystic Kidney Disease via Activation of the Hippo-YAP Signaling Pathway.

Autosomal dominant polycystic kidney disease (ADPKD) is a complex process, involving the alteration of multiple genes and signaling pathways, and the pathogenesis of ADPKD remains largely unknown. Here, we demonstrated the suppressive role of sorting nexin 9 (SNX9) during ADPKD development. Sorting nexin 9 expression was detected in the kidney tissues of ADPKD patients, for the first time, and SNX9 expression was also detected in Pkd1 knockout (Pkd1 -/-) and control mice. Subsequently, a series of gain- and loss-of-function studies were performed, to explore the biological roles and underlying molecular mechanisms of SNX9 in ADPKD progression. The expression of SNX9 was significantly downregulated in ADPKD patients and Pkd1 -/- mice compared with control individuals and wild-type mice (Pkd1+/+), respectively. The ectopic expression of SNX9 significantly inhibited ADPKD cell proliferation, renal cyst formation and enlargement, whereas these effects were promoted by SNX9 silencing. Mechanistically, we found that SNX9 interacted directly with yes-associated protein (YAP) and increased the large tumor suppressor kinase 1-mediated phosphorylation of YAP, resulting in the cytoplasmic retention of YAP, the decreased transcriptional activity of the YAP/TEA domain transcription factor 4 complex, and, consequently, the inhibition of Hippo target gene expression and ADPKD development. Taken together, our findings provided novel insights into the role played by SNX9 during ADPKD pathogenesis and may reveal novel therapeutic approaches for ADPKD and related kidney diseases.

Metabolomics Evaluation of Patients With Stage 5 Chronic Kidney Disease Before Dialysis, Maintenance Hemodialysis, and Peritoneal Dialysis.

OBJECTIVE: Current treatment options for patients with stage 5 chronic kidney disease before dialysis (predialysis CKD-5) are determined by individual circumstances, economic factors, and the doctor's advice. This study aimed to explore the plasma metabolic traits of patients with predialysis CKD-5 compared with maintenance hemodialysis (HD) and peritoneal dialysis (PD) patients, to learn more about the impact of the dialysis process on the blood environment. METHODS: Our study enrolled 31 predialysis CKD-5 patients, 31 HD patients, and 30 PD patients. Metabolite profiling was performed using a targeted metabolomics platform by applying an ultra-high-performance liquid chromatography-tandem mass spectrometry method, and the subsequent comparisons among all three groups were made to explore metabolic alterations. RESULTS: Cysteine metabolism was significantly altered between predialysis CKD-5 patients and both groups of dialysis patients. A disturbance in purine metabolism was the most extensively changed pathway identified between the HD and PD groups. A total of 20 discriminating metabolites with large fluctuations in plasma concentrations were screened from the group comparisons, including 2-keto-D-gluconic acid, kynurenic acid, s-adenosylhomocysteine, L-glutamine, adenosine, and nicotinamide. CONCLUSION: Our study provided a comprehensive metabolomics evaluation among predialysis CKD-5, HD, and PD patients, which described the disturbance of metabolic pathways, discriminating metabolites and their possible biological significances. The identification of specific metabolites related to dialysis therapy might provide insights for the management of advanced CKD stages and inform shared decision-making.

Initial Experience of Sorafenib Neoadjuvant Therapy Combined with Retroperitoneoscopy in Treating T2 Large Renal Carcinoma.

OBJECTIVES: To investigate the safety and feasibility of sorafenib neoadjuvant therapy combined with retroperitoneoscopic radical nephrectomy (RRN) in treating T2 large renal cell carcinoma (RCC). METHODS: Retrospectively analyzed 5 cases (2 males and 3 females, aged 52-73 years) of T2 stage large RCC who receive preoperative sorafenib targeted treatment (400 mg bid for 1-3 months) and RRN between March, 2013, and July, 2014. Patient information, therapeutic regimen, drug adverse effect, tumor changes before and after surgery, and perioperative parameters were recorded. RESULTS: During the sorafenib therapy adverse effects included 2 cases of hypertension (Grade I toxicity), 1 case of hand-foot syndrome (Grade I), and 1 case of diarrhea (Grade II), which were all tolerable for patients. CT scan and histopathological tests confirmed significant reduction in the longest dimension (LD) and medium density (MD) of the tumor after therapy as well as tumor hemorrhage, necrosis, and cystic degeneration. All 5 patients received RRN surgery successfully around 2 weeks after drug discontinuation with only 1 case of perioperative complication. CONCLUSIONS: Sorafenib neoadjuvant therapy could significantly reduce the size and aggressiveness of T2 large renal tumors, thus reducing the operative challenge and enabling patients who were previously disqualified for operation to receive surgical treatment.

Application of renal-rotation techniques in retroperitoneoscopic partial nephrectomy.

Retroperitoneoscopic partial nephrectomy (RPN) is one of the standard methods for treating T1-stage renal carcinoma, which has a narrow operational space and a difficult surgical procedure. The aim of this study was to examine the safety and feasibility of renal-rotation techniques in RPN. Between April 2012 and June 2014, the renal-rotation technique in RPN was performed in 22 male and 16 female patients, aged between 31 and 75 years (mean, 52 years), with stage T1N0M0 renal-cell carcinoma. In 29 cases the tumor was located at the ventral side of the kidney, including 22 cases at the renal hilum, and in nine cases the tumor was located at the inferior pole of the kidney. The tumor size was between 1.5 and 4.6 cm (mean, 2.8 cm). The results showed that, in all 38 cases, the procedure was successfully accomplished without conversion to open surgery. There were no intraoperative complications and only three cases of postoperative complications. The surgery duration was between 45 and 116 min (mean, 59 min); blood loss was between 10 and 120 ml (mean, 40 ml) and no patients required a blood transfusion. The average kidney ischemia time was 21 min (range, 15-38 min). No patients had local recurrence or metastasis after follow-up of between one and 26 months. In conclusion, the application of the renal-rotation technique in RPN for tumors located at the ventral side, renal hilum or at the inferior pole of the kidney is safe and feasible and worth wider clinical application.

Pancreatic insulin-producing cells differentiated from human embryonic stem cells correct hyperglycemia in SCID/NOD mice, an animal model of diabetes.

BACKGROUND: Human pancreatic islet transplantation is a prospective curative treatment for diabetes. However, the lack of donor pancreases greatly limits this approach. One approach to overcome the limited supply of donor pancreases is to generate functional islets from human embryonic stem cells (hESCs), a cell line with unlimited proliferative capacity, through rapid directed differentiation. This study investigated whether pancreatic insulin-producing cells (IPCs) differentiated from hESCs could correct hyperglycemia in severe combined immunodeficient (SCID)/non-obese diabetic (NOD) mice, an animal model of diabetes. METHODS: We generated pancreatic IPCs from two hESC lines, YT1 and YT2, using an optimized four-stage differentiation protocol in a chemically defined culture system. Then, about 5-7 × 10(6) differentiated cells were transplanted into the epididymal fat pad of SCID/NOD mice (n = 20). The control group were transplanted with undifferentiated hESCs (n = 6). Graft survival and function were assessed using immunohistochemistry, and measuring serum human C-peptide and blood glucose levels. RESULTS: The pancreatic IPCs were generated by the four-stage differentiation protocol using hESCs. About 17.1% of differentiated cells expressed insulin, as determined by flow cytometry. These cells secreted insulin/C-peptide following glucose stimulation, similarly to adult human islets. Most of these IPCs co-expressed mature ß cell-specific markers, including human C-peptide, GLUT2, PDX1, insulin, and glucagon. After implantation into the epididymal fat pad of SCID/NOD mice, the hESC-derived pancreatic IPCs corrected hyperglycemia for ≥ 8 weeks. None of the animals transplanted with pancreatic IPCs developed tumors during the time. The mean survival of recipients was increased by implanted IPCs as compared to implanted undifferentiated hESCs (P<0.0001). CONCLUSIONS: The results of this study confirmed that human terminally differentiated pancreatic IPCs derived from hESCs can correct hyperglycemia in SCID/NOD mice for ≥8 weeks.

Celecoxib inhibits growth of human autosomal dominant polycystic kidney cyst-lining epithelial cells through the VEGF/Raf/MAPK/ERK signaling pathway.

Autosomal dominant polycystic kidney disease (ADPKD) is a progressive chronic kidney disease. To date there are no effective medicines to halt development and growth of cysts. In the present study, we explored novel effects of celecoxib (CXB), a COX-2 specific inhibitor, on primary cultures of human ADPKD cyst-lining epithelial cells. Primary cultures of ADPKD cyst-lining epithelial cells were obtained from five patients. Effects of CXB were measured by various assays to detect BrdU incorporation, apoptosis and proliferation in vitro. Additionally, effects of CXB on kidney weight, the cyst index, the fibrosis index, blood urea nitrogen (BUN), serum creatinine (SCr), serum 6-keto-PGF-1α, serum thromboxane-2 (TXB2) and renal PCNA expression were assessed in Han:SPRD rat, a well-characterized rodent model of PKD. CXB inhibited proliferation of ADPKD cyst-lining epithelial cells, blocked the release of VEGF from the cells and induced extensive apoptosis in a time- and dose-dependent manner. Moreover, CXB up-regulated the cell cycle negative regulator p21(CIP/WAF1) and the cell cycle positive regulator Cyclin A, blocked ERK1/2 phosphorylation, induced apoptotic factors (Bax and caspase-3) and reduced Bcl-2. Furthermore, CXB inhibited the expression of VEGFR-2 and Raf-1 in ADPKD cyst-lining epithelial cells. CXB markedly reduced the cyst index, the fibrosis index, leukocyte infiltration, BUN, SCr, serum 6-keto-PGF-1α, TXB2 and renal PCNA expression in Han:SPRD rat. We demonstrated for the first time that CXB could suppress renal cyst-lining growth both in vitro and in vivo in Han:SPRD rat. CXB can inhibit proliferation, suppress cell cycle progression, and induce apoptosis in ADPKD cyst-lining epithelial cells through the inhibition of the VEGF/VEGFR-2/Raf-1/MAPK/ERK signaling pathway.

Differences in phenotype and gene expression of prostate stromal cells from patients of varying ages and their influence on tumour formation by prostate epithelial cells.

Prostate cancer (PCa) is an age-related disease, and the stromal microenvironment plays an important role in prostatic malignant progression. However, the differences in prostate stromal cells present in young and old tissue are still obscure. We established primary cultured stromal cells from normal prostatic peripheral zone (PZ) of donors of varying ages and found that cultured stromal cells from old donors (PZ-old) were more enlarged and polygonal than those from young donors (PZ-young). Furthermore, based on immunocytochemical and ultrastructural analysis, the components of stromal cells changed from a majority of fibroblasts to a mixture of fibroblasts and myofibroblasts with increasing donor age. Using a three-dimensional in vitro culture system, we found that PZ-old stromal cells could enhance the proliferation, migration and invasion of cocultured benign BPH-1 and PC-3 cells. Using an in vivo tissue recombination system, we also found that PZ-old stromal cells are more effective than PZ-young cells in promoting tumour formation by BPH-1 cells of high passage (>100) and PC-3 cells. To probe the possible mechanism of these effects, we performed cDNA microarray analysis and profiled 509 upregulated genes and 188 downregulated genes in PZ-old cells. Among the changed genes, we found genes coding for a subset of paracrine factors that are capable of influencing adjacent epithelial cells; these include hepatocyte growth factor (HGF), fibroblast growth factor 5 (FGF5), insulin-like growth factor 2 (IGF2), insulin-like growth factor-binding protein 4 (IGFBP4), IGFBP5 and matrix metallopeptidase 1 (MMP1). Changes in the expression of these genes were further confirmed by quantitative real-time polymerase chain reaction (PCR), Western blotting and enzyme-linked immunosorbent assays. Overall, our findings indicate that stromal cells from prostate PZ of old donors are more active than similar cells from young donors in promoting the malignant process of adjacent epithelial cells. This finding hints at a new potential strategy for the prevention of PCa.

[Characterization of stromal cell cultures from the prostatic peripheral zone of men at different ages].

OBJECTIVE: To characterize age-related cellular phenotype alterations and growth rates of human prostatic stromal cell cultures from the normal prostatic peripheral zone of young donors (PZ-young) and old donors (PZ-old). METHODS: We isolated stromal cells from 10 donors of different ages, assessed the cellular phenotypes by immunocytostaining for prolyl-4-hydroxylase, alpha-smooth muscle actin (alpha-SMA) and desmin, and analysed the ultrastructure by transmission electron microscopy (TEM). The proliferation and apoptosis of the cells were determined by Cell Counting Kit-8 assay and flow cytometry, respectively. RESULTS: All the stromal cells were positive for prolyl-4-hydroxylase regardless of the donors' age, while alpha-SMA and desmin positive cells increased with their age. The positive expressions of alpha-SMA and desmin were (2.56 +/- 1.81)% and (0.89 +/- 0.93)% in PZ-young, and (38.89 +/- 11.22)% and (14.89 +/- 5.97)% in PZ-old (P < 0.01). The alpha-SMA- and/or desmin-positive stromal cells were morphologically large, flat and polygonal. Ultrastructural analysis showed that the cell cultures from PZ-old were richer in rough endoplasmic reticulum and golgi complexes. The stromal cells of PZ-old had a lower growth rate than that of PZ-young (P < 0.01), but there was no significant difference in the apoptosis rate between the two groups. CONCLUSION: Cellular phenotypes of human prostate stromal cell cultures change with the increase of age from predominantly typical fibroblasts to a mixture of fibroblasts and myofibroblasts, which might responsible for the high incidence of prostate cancer in elderly men.

Androgen receptor is a potential therapeutic target for bladder cancer.

OBJECTIVES: To investigate whether androgen receptor (AR) could serve as a potential molecular target for the treatment of bladder cancer. METHODS: Cell proliferation, apoptosis, and migration capacity were determined in human transitional carcinoma cell lines T24 and 253-J treated with small interfering RNA directed against AR, and expression levels of growth- and metastasis-related genes were assessed using quantitative reverse transcriptase-polymerase chain reaction. Tumor cell growth and apoptosis were also evaluated in vivo in T24 tumor-bearing nude mice receiving electroporation-assisted administration of anti-AR small interfering RNA. RESULTS: AR expression knockdown produced increased apoptosis, decreased proliferation, and migration of bladder cancer cells. Cyclin D1, Bcl-x(L), and matrix metallopeptidase-9 gene expression were also reduced with AR knockdown, which might have contributed to the altered biological behavior of cancer cells. In vivo experiments showed that silencing AR expression, by interference aided by electroporation, significantly suppressed AR-positive bladder tumor growth with decreased cell proliferation and increased apoptotic rates. CONCLUSIONS: Downregulation of AR expression inhibits bladder cancer cell growth in vitro and in vivo, implying that its use might be a potential therapeutic target for the treatment of bladder cancer.

Androgen receptor functioned as a suppressor in the prostate cancer cell line PC3 in vitro and in vivo.

BACKGROUND: Prostate cancer is one of the most common urogenital tumors in the world with an increasing incidence in China. Androgen deprivation therapy is the major therapeutic option for advanced prostate cancer. However, the role of androgen receptor (AR) in hormone-refractory prostate cancer still remains unclear. This work aimed to investigate the role of AR in an androgen independent prostate cancer cell line by in vitro and in vivo studies. METHODS: The role of AR in the proliferation and invasion/metastasis ability of PC3-AR9 (a PC3 stable clone expressing human AR driven by natural human AR promoter) were examined with MTT assay, soft agar assay, chamber invasion assay, wound healing assay, and also with orthotopic xenograft mouse model. RESULTS: Restoring androgen receptor in PC3 cells resulted in decreased proliferation and invasion/metastasis ability in MTT, soft agar, chamber invasion and wound healing assay. In the mouse orthotopic xenograft model, PC3-AR9 resulted in smaller primary tumors and metastasis tumors, with a lower proliferation rate and higher apoptosis rate. CONCLUSION: The AR might function as a tumor suppressor in PC3 cells both in vitro and in vivo.

The influence of ureteral stent on renal pelvic pressure in vivo.

The objective of this study was to explore the influence of ureteral stent on renal pelvic pressure by urodynamic study. 41 patients (with unilateral renal and/or ureteral calculi) after minimally invasive percutaneous nephrolithotomy (MPCNL) were placed a 4.7-Fr ureteral stent and 16-Fr nephrostomy tube. Renal pelvic pressure of these patients was measured by urodynamic study at the 5-7 days after MPCNL. Renal pelvic pressure (RPP), intraabdominal pressure (IAP), and vesical pressure (VP) during the filling and voiding phases were detected by urodynamic study with intravesical perfusion. At the baseline, intraabdominal pressure (IAP(0)) was 27.52 +/- 7.03 cmH(2)O, renal pelvic pressure (RPP(0)) was 33.07 +/- 7.04 cmH(2)O; at the maximum cystometric bladder capacity (MCBC) during the filling phase, vesical pressure (VP(vol)) was 41.61 +/- 10.34 cmH(2)O, renal pelvic pressure (RPP(vol)) was 39.44 +/- 7.33 cmH(2)O; at the maximum vesical pressure during the voiding phase, vesical pressure (VP(max)) was 74.95 +/- 12.79 cmH(2)O, renal pelvic pressure (RPP(max)) was 65.68 +/- 17.03 cmH(2)O. (1) There was a strong relationship between RPP(0) and IAP(0) (P = 0.0001); (2) There was statistical significance among RPP(0), RPP(vol) and RPP(max) (P = 0.0001); (3) RPP was higher than 40 cmH(2)O during the voiding phase, and it was obviously relevant to the VP (P = 0.0001) but not to the MCBC (P = 0.2696). RPP increased mildly during the filling phase and dramatically during the voiding phase after stenting. RPP increased higher than the level required for a backflow (40 cmH(2)O) during the voiding phase. So it was encouraged to remove the stent at earlier stage or decrease using the ureteral stent if possible.

Tumor formation of prostate cancer cells influenced by stromal cells from the transitional or peripheral zones of the normal prostate.

This study was designed to investigate the different involvements of prostatic stromal cells from the normal transitional zone (TZ) or peripheral zone (PZ) in the carcinogenesis of prostate cancer (PCa) epithelial cells (PC-3) in vitro and in vivo co-culture models. Ultra-structures and gene expression profiles of primary cultures of human prostatic stromal cells from the normal TZ or PZ were analyzed by electron microscopy and microarray analysis. In vitro and in vivo co-culture models composed of normal TZ or PZ stromal cells and human PCa PC-3 cells were established. We assessed tumor growth and weight in the in vivo nude mice model. There are morphological and ultra-structural differences in stromal cells from TZ and PZ of the normal prostate. In all, 514 differentially expressed genes were selected by microarray analysis; 483 genes were more highly expressed in stromal cells from TZ and 31 were more highly expressed in those from PZ. Co-culture with PZ stromal cells and transforming growth factor-beta1 (TGF-beta1) increased the tumor growth of PC-3 cells in vitro and in vivo, as well as Bcl-2 expression. On the other hand, stromal cells of TZ suppressed PC-3 cell tumor growth in the mouse model. We conclude that ultra-structures and gene expression differ between the stromal cells from TZ or PZ of the normal prostate, and stroma-epithelium interactions from TZ or PZ might be responsible for the distinct zonal localization of prostate tumor formation.

The diverse and contrasting effects of using human prostate cancer cell lines to study androgen receptor roles in prostate cancer.

The androgen receptor (AR) plays an important role in the development and progression of prostate cancer (PCa). Androgen deprivation therapy is initially effective in blocking tumor growth, but it eventually leads to the hormone-refractory state. The detailed mechanisms of the conversion from androgen dependence to androgen independence remain unclear. Several PCa cell lines were established to study the role of AR in PCa, but the results were often inconsistent or contrasting in different cell lines, or in the same cell line grown under different conditions. The cellular and molecular alteration of epithelial cells and their microenvironments are complicated, and it is difficult to use a single cell line to address this important issue and also to study the pathophysiological effects of AR. In this paper, we summarize the different effects of AR on multiple cell lines and show the disadvantages of using a single human PCa cell line to study AR effects on PCa. We also discuss the advantages of widely used epithelium-stroma co-culture systems, xenograft mouse models, and genetically engineered PCa mouse models. The combination of in vitro cell line studies and in vivo mouse models might lead to more credible results and better strategies for the study of AR roles in PCa.

Chimeric molecules facilitate the degradation of androgen receptors and repress the growth of LNCaP cells.

Post-translational degradation of protein plays an important role in cell life. We employed chimeric molecules (dihydrotestosterone-based proteolysis-targeting chimeric molecule [DHT-PROTAC]) to facilitate androgen receptor (AR) degradation via the ubiquitin-proteasome pathway (UPP) and to investigate the role of AR in cell proliferation and viability in androgen-sensitive prostate cancer cells. Western blot analysis and immunohistochemistry were applied to analyse AR levels in LNCaP cells after DHT-PROTAC treatment. Cell counting and the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) cell viability assay were used to evaluate cell proliferation and viability after AR elimination in both LNCaP and PC-3 cells. AR was tagged for elimination via the UPP by DHT-PROTAC, and this could be blocked by proteasome inhibitors. Degradation of AR depended on DHT-PROTAC concentration, and either DHT or an ALAPYIP-(arg)(8) peptide could compete with DHT-PROTAC. Inhibition of cell proliferation and decreased viability were observed in LNCaP cells, but not in PC-3 or 786-O cells after DHT-PROTAC treatment. These data indicate that AR elimination is facilitated via the UPP by DHT-PROTAC, and that the growth of LNCaP cells is repressed after AR degradation.