Vitamin D increases the efcacy of cisplatin on bladder cancer cell lines

Abstract

Background 1,25(OH)2D3(Calcitriol), which is a broad regulatory molecule, plays a role in changing the efcacy of chemo therapeutic drugs. Cisplatin is one of a current standard chemotherapy regimen for bladder cancer. Increasing the efectiveness of the treatment and reducing the side efects to chemotherapeutics are of great importance in bladder cancer. We aimed to investigate the efect of the combination of cisplatin and calcitriol in order to create a possible advantage in treatment of bladder cancer. Methods T24, ECV-304 and HUVEC cell lines were treated with calcitriol and cisplatin individually and in combination. Dose determination and combination treatments of calcitriol and cisplatin were evaluated using the MTT assay for cytotox icity analysis on the cells. Annexin V-PI staining method was used for apoptosis determination by fow cytometry. Also the P-gp expression levels were determined by fow cytometry. Results The combination treatment increased the anti-proliferative efcacy compared to the efcacy in cisplatin alone in T24 cells and reduced the cytotoxicity in the HUVEC healthy cells compared to cisplatin alone. Combination treatment achieved signifcantly higher apoptosis rate in T24 cells compared with the rates in treatment of cisplatin alone. However apoptosis decreased in HUVEC cell line. P-gp ratios were increased in HUVEC and decreased in T24 cells with combina tion treatment compared to the numbers in the control cells. The rate of apoptosis and P-gp levels showed no signifcant change in ECV-304 cells. Conclusion Our study revealed that the combination of calcitriol and cisplatin allows the use of cisplatin at lower doses in T24 bladder cancer cell line