No abstract

Background/Aims: Ginkgolide B (GB) is currently used as an anticancer drug for treatment of some malignant cancers. However, whether it may have therapeutic effects on bladder cancer remains unknown. Here, we studied the effects of GB on bladder cancer cells. Methods: Bladder cells were treated with different doses of GB, and the effects on ZEB1 and microRNA-223-3p (miR-223-3p) were analyzed by RT-qPCR and/or Western blot. Prediction of a regulatory relationship between miR-93 and 3'-UTR of Beclin-1 mRNA was performed by a bioinformatics algorithm and confirmed by a dual luciferase reporter assay. Results: We found that GB dose-dependently decreased ZEB1 protein, but not mRNA, in bladder cancer cells, resulting in suppression of cell invasion. Moreover, in bladder cancer cells, GB dose-dependently decreased the levels of miR-223-3p, which suppressed the protein translation of ZEB1 through binding to 3'-UTR of ZEB1 mRNA. Overexpression of miR-223-3p decreased ZEB1 protein, while depletion of miR-223-3p increased ZEB1 protein in bladder cancer cells. Conclusion: GB inhibits bladder cancer cell invasiveness through suppressing ZEB1 protein translation via upregulating miR-223-3p.

No abstract

OBJECTIVE To evaluate the activity of large‐ and small‐conductance calcium‐activated potassium channels (BKCa, SKCa) and calcium‐activated chloride channels (ClCa) in detrusor overactivity (DO) cells after partial bladder outlet obstruction (PBOO) in rats. MATERIALS AND METHODS Thirteen female Wistar rats with DO caused by PBOO were studied simultaneously with eight sham‐operated rats. The expression of KCa and ClCa channels was assessed by reverse transcription‐polymerase chain reaction, and the function of the two groups compared. RESULTS In the DO cells the expression of BKCa, SKCa2 and SKCa3 was lower, and that of ClCa channels higher, than in the control group cells. Using confocal laser scanning microscopic analysis, the function of BKCa and SKCa channels was suppressed, and that of ClCa channels was enhanced in DO group cells. KCa and ClCa effectors altered the cell membrane potentials more significantly in the DO cells than in the control cells, indicating a decrease in KCa and an increase in ClCa in DO group in either iso‐ or hypo‐osmolar medium. Moreover, the change in BKCa, SKCa and ClCa channel activators in DO cells showed a more excitable state in hypo‐osmolar medium than in iso‐osmolar medium. CONCLUSION In DO myocytes after PBOO, the expression and function of KCa channels were decreased, and those of ClCa channels increased. These changes all provoke greater cell excitability, and could partly account for the DO.

Abnormal activation of Notch signaling is involved in the etiology of various diseases, including cancer, but the association between Notch3 expression in urothelial cancer and clinical outcome remains unclear, and the molecular mechanisms underlying Notch3 signaling activation are not well defined. In this study we examined 59 urothelial cancer patients and found that Notch3 was more highly expressed in human urothelial cancer tissues than in non-tumorous bladder tissue samples, with Notch3 overexpression being associated with poor clinical outcome. Notch3 knockdown resulted in decreased proliferation of urothelial cancer cells in vitro and decreased xenograft tumor growth in vivo. In addition, Notch3 knockdown rendered urothelial cancer cells more sensitive to cisplatin. Furthermore, suberoylanilide hydroxamic acid (SAHA, a histone deacetylase [HDAC] inhibitor) induced acetylation of NOTCH3, downregulated Notch 3, prevented urothelial cancer cell proliferation, and induced cell cycle arrest. Taken together, these data suggested that Notch 3 overexpression promotes growth and chemoresistance in urothelial cancer.

Human renal cancer is extremely resistant to chemotherapy and radiation therapy. This clinical characteristic reduces the efficacy of chemotherapeutic agents in the treatment of recurrence or metastasis following surgical resection. Understanding the mechanism of chemotherapy resistance in renal cell carcinoma remains a significant challenge. In this study, we have shown that varied level of XPF expression was organ-tissue specific by comparing human renal cancer, bladder cancer, testicular cancer and their normal tissue counterparts, respectively. The expression of XPF was significantly higher in renal cancer than in bladder cancer and testicular cancer and correlated with the clinical characteristic of their chemotherapeutics sensitivity. These novel findings proposed that the intrinsic chemoresistance of human renal cell carcinomas might be derived from the high level of XPF expression. In a panel of five cancer cell lines, decreasing cisplatin sensitivity correlated with increasing levels of XPF expression. Knockdown of XPF expression not only increased sensitivity of renal carcinoma cells to cisplatin treatment by affecting the DNA damage response, including DNA repair, cell cycle regulation and apoptosis, but also increased senescence of renal cancer cell. Furthermore, experiment in vivo confirmed that silenced XPF significantly increased the sensitivity and survival following treatment with cisplatin in xenograft mice bearing renal cell tumor. These findings firstly uncover a partial mechanism of intrinsic chemoresistance in renal cancer and may provide a new approach to break through the obstacle of intrinsic chemoresistance by targeting the XPF protein with a potential new inhibitor.

No abstract

No abstract