Potential therapeutic target secretogranin II might cooperate with hypoxia-inducible factor 1α in sunitinib-resistant renal cell carcinoma.

Multitargeted receptor tyrosine kinase inhibitors, including vascular endothelial growth factor (VEGF) inhibitors, such as sunitinib, have been used as the primary targeted agents for patients with recurrent or distant metastasis of advanced renal cell carcinoma (RCC). However, endogenous or acquired sunitinib resistance has become a significant therapeutic problem. Therefore, we focused on mechanisms of sunitinib resistance in RCC. First, we undertook RNA sequencing analysis using previously established sunitinib-resistant RCC (SUR-Caki1, SUR-ACHN, and SUR-A498) cells. The results showed increased expression of secretogranin II (SCG2, chromogranin C) in SUR-RCC cells compared to parental cells. The Cancer Genome Atlas database showed that SCG2 expression was increased in RCC compared to normal renal cells. In addition, the survival rate of the SCG2 high-expression group was significantly lower than that of the RCC low-expression group. Thus, we investigated the involvement of SCG2 in sunitinib-resistant RCC. In vitro analysis showed that migratory and invasive abilities were suppressed by SCG2 knockdown SUR cells. As SCG2 was previously reported to be associated with angiogenesis, we undertook a tube formation assay. The results showed that suppression of SCG2 inhibited angiogenesis. Furthermore, coimmunoprecipitation assays revealed a direct interaction between SCG2 and hypoxia-inducible factor 1α (HIF1α). Expression levels of VEGF-A and VEGF-C downstream of HIF1α were found to be decreased in SCG2 knockdown SUR cells. In conclusion, SCG2 could be associated with sunitinib resistance through VEGF regulation in RCC cells. These findings could lead to a better understanding of the VHL/HIF/VEGF pathway and the development of new therapeutic strategies for sunitinib-resistant RCC.

Characterization and treatment of gemcitabine- and cisplatin-resistant bladder cancer cells with a pan-RAS inhibitor.

Combination chemotherapy with gemcitabine and cisplatin (GC) is recommended as the primary treatment for advanced bladder cancer (BC). However, the benefits of this approach are limited owing to the acquisition of drug resistance. Here, we found that gemcitabine-resistant and cisplatin-resistant BCs do not exhibit cross-resistance, and that these BCs exhibit different mRNA patterns, as revealed using RNA sequence analysis. To overcome drug resistance, we used the newly developed pan-RAS inhibitor Compound 3144. Compound 3144 inhibited cell viability through suppression of RAS-dependent signaling in gemcitabine- and cisplatin-resistant BCs. RNA sequencing revealed that several genes and pathways, particularly those related to the cell cycle, were significantly downregulated in Compound 3144-treated BCs. These findings provide insights into potential therapeutic strategies for treating BC.

Exosomal microRNA-1 and MYO15A as a target for therapy and diagnosis in renal cell carcinoma.

Exosomes are 40-100 nm nano-sized extracellular vesicles and are receiving increasing attention as novel structures that participate in intracellular communication. We previously found that miRNA-1 (miR-1) functions as a tumor suppressor in renal cell carcinoma (RCC). In this study, we investigated the function of exosomal miR-1 and the possibility that the exosome constitutes a tumor maker in RCC. First, we established the method to collect exosomes from cell lysates and human serum by a spin column-based method. Next, we assessed exosomes using Nanosight nanoparticle tracking analysis and Western blot analysis with exosome marker CD63. We confirmed that exosomes labeled with PKH26 fused with recipient cells. Moreover, miR-1 expression was elevated in RCC cells treated with exosomes derived from miR-1-transfected cells. Functional analyses showed that exosomal miR-1 significantly inhibited cell proliferation, migration and invasion compared to control treatment. Our analyses with TCGA database of RCCs showed that miR-1 expression was significantly downregulated in clinical RCC samples compared to that in normal kidney samples, and patients with low miR-1 expression had poorer overall survival in comparison to patients with high expression. Furthermore, RNA sequence analyses showed that expression levels of several genes were altered by exposure to exosomal miR-1. The analyses with TCGA database indicated that high expression of MYO15A was associated with a poorer outcome in RCC. In addition, RT-qPCR analysis of exosomes from clinical patients' sera showed that MYO15A was significantly upregulated in RCC patients compared to that in healthy controls. This study showed that treatment with exosomal miR-1 might be an effective approach to treating RCCs. In addition, exosomal MYO15A could be a diagnostic tumor marker in RCCs.

Laparoscopic Surgery for Pheochromocytoma in Hemodialysis Patients.

Objectives: We analyzed the clinical outcomes of laparoscopic adrenalectomy for pheochromocytomas in hemodialysis compared with nonhemodialysis patients. Methods: Fifty-seven patients (7 hemodialysis and 50 nonhemodialysis) were included in the study. We analyzed the differences in clinical parameters and outcomes between the hemodialysis patient groups and nonhemodialysis patient groups as well as identified predictors for an intraoperative hypertensive spike. Results: The increasing intravascular volume before surgery in hemodialysis patients made perioperative hemodynamic management safer. No significant difference in clinical parameters between the two groups was observed except for the length of hospitalization that was significantly longer in the hemodialysis patients (9 vs. 6 days, P=0.005). An increase in systolic blood pressure at CO2 insufflation was an independent predictor of a hypertensive spike with a cutoff value of 22.5 mmHg (odds ratio 1.038, 95% confidence interval 1.012-1.078). Conclusion: Laparoscopic adrenalectomy for pheochromocytomas in hemodialysis was safe and feasible. An increase in systolic blood pressure at CO2 insufflation was a predictor of the intraoperative hypertensive spike. The research in this manuscript is not registered. This is a retrospective study.

Targeting of the glutamine transporter SLC1A5 induces cellular senescence in clear cell renal cell carcinoma.

In recent years, cancer metabolism has attracted attention as a therapeutic target, and glutamine metabolism is considered one of the most important metabolic processes in cancer. Solute carrier family 1 member 5 (SLC1A5) is a sodium channel that functions as a glutamine transporter. In various cancer types, SLC1A5 gene expression is enhanced, and cancer cell growth is suppressed by inhibition of SLC1A5. However, the involvement of SLC1A5 in clear cell renal cell carcinoma (ccRCC) is unclear. Therefore, in this study, we evaluated the clinical importance of SLC1A5 in ccRCC using The Cancer Genome Atlas database. Our findings confirmed that SLC1A5 was a prognosis factor for poor survival in ccRCC. Furthermore, loss-of-function assays using small interfering RNAs or an SLC1A5 inhibitor (V9302) in human ccRCC cell lines (A498 and Caki1) showed that inhibition of SLC1A5 significantly suppressed tumor growth, invasion, and migration. Additionally, inhibition of SLC1A5 by V9302 in vivo significantly suppressed tumor growth, and the antitumor effects of SLC1A5 inhibition were related to cellular senescence. Our findings may improve our understanding of ccRCC and the development of new treatment strategies for ccRCC.

Mid-Term Safety and Efficacy of the Modified Double Hydrodistention Implantation Technique (HIT), Termed Systematic Multi-Site HIT (SMHIT), for Patients with Primary Vesicoureteral Reflux.

PURPOSE: To evaluate the treatment outcomes and postoperative complications associated with the systematic multi-site hydrodistention implantation technique (SMHIT) for primary vesicoureteral reflux (VUR) and to determine its mid-term efficacy and safety. PATIENTS AND METHODS: We retrospectively reviewed the data for 17 ureters from 12 consecutive children, aged ≥1 year, with grade II-IV reflux and a history of febrile urinary tract infections (FUTI), who underwent a single-session of SMHIT. The primary outcome was the absence of postoperative FUTI (clinical success). The secondary outcome was improvement in reflux to grade 0-I on postoperative voiding cystourethrography (radiographic success). RESULTS: Five and 7 children had bilateral and unilateral reflux, respectively. Reflux was categorized as grade II, III, and IV reflux in 2, 12, and 3 ureters, respectively. Seven of 10 (70%) toilet-trained children had bladder-bowel dysfunction (BBD) preoperatively. The SMHIT was performed for all patients, after which BBD improved. The mean postoperative follow-up period was 6 years and 9 months. The clinical success rate was 100%. Radiographic success was achieved in 16/17 ureters (94%) at 3-4 months, 17/17 (100%) ureters at 1 year, and 17/17 (100%) ureters at 3 years postoperatively. Major complications did not develop postoperatively. CONCLUSION: When prioritizing treatment of concomitant BBD in children with primary VUR and avoiding dextranomer/hyaluronic acid injection therapy in contraindicated children according to the Food and Drug Administration recommendations, a single-session of SMHIT may be as effective and safe in the mid-term as performing open anti-reflux surgery.

Regulation of UHRF1 by dual-strand tumor-suppressor microRNA-145 (miR-145-5p and miR-145-3p): Inhibition of bladder cancer cell aggressiveness.

In microRNA (miRNA) biogenesis, the guide-strand of miRNA integrates into the RNA induced silencing complex (RISC), whereas the passenger-strand is inactivated through degradation. Analysis of our miRNA expression signature of bladder cancer (BC) by deep-sequencing revealed that microRNA (miR)-145-5p (guide-strand) and miR-145-3p (passenger-strand) were significantly downregulated in BC tissues. It is well known that miR-145-5p functions as a tumor suppressor in several types of cancer. However, the impact of miR-145-3p on cancer cells is still ambiguous. The aim of the present study was to investigate the functional significance of miR-145-3p and BC oncogenic pathways and targets regulated by miR-145-5p/miR-145-3p. Ectopic expression of either miR-145-5p or miR-145-3p in BC cells significantly suppressed cancer cell growth, migration and invasion and it also induced apoptosis. The gene encoding ubiquitin-like with PHD and ring finger domains 1 (UHRF1) was a direct target of these miRNAs. Silencing of UHRF1 induced apoptosis and inhibited cancer cell proliferation, migration, and invasion in BC cells. In addition, overexpressed UHRF1 was confirmed in BC clinical specimens, and the high UHRF1 expression group showed a significantly poorer cause specific survival rate in comparison with the low expression group. Taken together, our present data demonstrated that both strands of miR-145 (miR-145-5p: guide-strand and miR-145-3p: passenger-strand) play pivotal roles in BC cells by regulating UHRF1. The identification of the molecular target of a tumor suppressive miRNAs provides novel insights into the potential mechanisms of BC oncogenesis and suggests novel therapeutic strategies.

Tumour-suppressive microRNA-29s directly regulate LOXL2 expression and inhibit cancer cell migration and invasion in renal cell carcinoma.

Here, we found that members of the microRNA-29 family (miR-29a/b/c; "miR-29s") were significantly reduced in clear cell renal cell carcinoma (ccRCC) tissues, suggesting that they functioned as tumour suppressors. Restoration of all mature members of the miR-29 family inhibited cancer cell proliferation, migration and invasion. LOXL2 was a direct target gene of miR-29s, as shown by genome-wide gene expression analysis and luciferase reporter assay. Overexpressed LOXL2 was confirmed in ccRCC clinical specimens, and silencing of LOXL2 inhibited cancer cell migration and invasion in ccRCC cell lines. Our data demonstrated that the miR-29s-LOXL2 axis contributed to cancer cell migration and invasion in ccRCC.

Dual regulation of receptor tyrosine kinase genes EGFR and c-Met by the tumor-suppressive microRNA-23b/27b cluster in bladder cancer.

Recent clinical trials of chemotherapeutics for advanced bladder cancer (BC) have shown limited benefits. Therefore, new prognostic markers and more effective treatment strategies are required. One approach to achieve these goals is through the analysis of RNA networks. Our recent studies of microRNA (miRNA) expression signatures revealed that the microRNA-23b/27b (miR-23b/27b) cluster is frequently downregulated in various types of human cancers. However, the functional role of the miR-23b/27b cluster in BC cells is still unknown. Thus, the aim of the present study was to investigate the functional significance of the miR-23b/27b cluster and its regulated molecular targets, with an emphasis on its contributions to BC oncogenesis and metastasis. The expression levels of the miR-23b/27b cluster were significantly reduced in BC clinical specimens. Restoration of mature miR-23b or miR-27b miRNAs significantly inhibited cancer cell migration and invasion, suggesting that these clustered miRNAs function as tumor suppressors. Gene expression data and in silico analysis demonstrated that the genes coding for the epidermal growth factor receptor (EGFR) and hepatocyte growth factor receptor (c-Met) were potential targets of the miR-23b/27b cluster. Luciferase reporter assays and western blotting demonstrated that EGFR and c-Met receptor trypsine kinases were directly regulated by these clustered miRNAs. We conclude that the decreased expression of the tumor-suppressive miR-23b/27b cluster enhanced cancer cell proliferation, migration and invasion in BC through direct regulation of EGFR and c-Met signaling pathways. Our data on RNA networks regulated by tumor-suppressive miR-23b/27b provide new insights into the potential mechanisms of BC oncogenesis and metastasis.

Tumour-suppressive microRNA-24-1 inhibits cancer cell proliferation through targeting FOXM1 in bladder cancer.

Here, we found that microRNA-24-1 (miR-24-1) is significantly reduced in bladder cancer (BC) tissues, suggesting that it functions as a tumour suppressor. Restoration of mature miR-24-1 inhibits cancer cell proliferation and induces apoptosis. Forkhead box protein M1 (FOXM1) is a direct target gene of miR-24-1, as shown by genome-wide gene expression analysis and luciferase reporter assay. Overexpressed FOXM1 is confirmed in BC clinical specimens, and silencing of FOXM1 induces apoptosis in cancer cell lines. Our data demonstrate that the miR-24-1-FOXM1 axis contributes to cancer cell proliferation in BC, and elucidation of downstream signalling will provide new insights into the molecular mechanisms of BC oncogenesis.

Expression of the tumor suppressive miRNA-23b/27b cluster is a good prognostic marker in clear cell renal cell carcinoma.

PURPOSE: We observed abnormal expression of the microRNA-23b/27b (miR-23b/27b) cluster in our previous study of miRNA expression signatures. However, the relationship between aberrant miRNA expression and clear cell renal cell carcinoma is not well established. We investigated the functional significance of the miR-23b/27b cluster in clear cell renal cell carcinoma cells and evaluated these miRNAs as biomarkers to predict the risk of clear cell renal cell carcinoma. MATERIALS AND METHODS: Expression levels of miR-23b and miR-27b were determined by quantitative real-time reverse transcriptase-polymerase chain reaction. The association between miRNA expression and overall survival was estimated by the Kaplan-Meier method. Gain of function assays were performed using mature miR-23b and miR-27b in the 786-O and A498 renal cell carcinoma cell lines. Targets regulated by these miRNAs were predicted by in silico analysis. RESULTS: Expression of the miR-23b/27b cluster was significantly decreased in clear cell renal cell carcinoma tissue specimens and associated with pathological grade and stage. Significantly shorter overall survival was observed in patients with lower expression of the miR-23b/27b cluster. Restoration of miR-23b and miR-27b significantly inhibited cancer cell proliferation, migration and invasion. CONCLUSIONS: Expression of the miR-23b/27b cluster was frequently decreased in clear cell renal cell carcinoma tissue. Reduced expression of these miRNAs increased the risk of disease progression and predicted poor survival. Thus, miR-23b and miR-27b function as tumor suppressors, targeting several oncogenic genes in clear cell renal cell carcinoma cells.

Tumour-suppressive microRNA-224 inhibits cancer cell migration and invasion via targeting oncogenic TPD52 in prostate cancer.

Our recent study of the microRNA expression signature of prostate cancer (PCa) revealed that microRNA-224 (miR-224) is significantly downregulated in PCa tissues. Here, we found that restoration of miR-224 significantly inhibits PCa cell migration and invasion. Additionally, we found that oncogenic TPD52 is a direct target of miR-224 regulation. Silencing of the TPD52 gene significantly inhibits cancer cell migration and invasion. Moreover, TPD52 expression is upregulated in cancer tissues and negatively correlates with miR-224 expression. We conclude that loss of tumour-suppressive miR-224 enhances cancer cell migration and invasion in PCa through direct regulation of oncogenic TPD52.