Molecular effects of vitamin D on bladder cancer

It is a great importance for patients to investigate the efficacy of the use of chemotherapeutics and to study drug combinations to reduce side effects of treatment. Vitamin D has been shown to have anti-proliferative, differential and metabolic regulation effects in different cancer cell lines. Our study was performed in vitro and the combinations of different doses of Vitamin D and cisplatin on T24, ECV-304 and HUVEC cell lines were evaluated for cytotoxic, apoptotic and drug resistance. It was evaluated whether cisplatin, which is used in bladder cancer treatment, will have an effect-enhancing and dose-reducing effect in order to reduce the possible side effects in combination with Vitamin D. Datas showed that 500nM calcitriol dose in combination with 5µg / ml cisplatin increased the anti-proliferative efficacy compared to cisplatin alone (p <0.0108). In the healthy control cell line, HUVEC showed that 500nM calcitriol dose and combined with 5µg / ml cisplatin prevented the decrease in viability compared to cisplatin alone (p <0.0001). P-gp rates were increased with combined cisplatin and calcitriol administration in HUVEC (92.16% p <0.0001) compared to control (87.08% p <0.0001). The P-gp ratio (68.33% p <0.0001) of combined administration of cisplatin and calcitriol in T24 decreased compared to control (74.47% p <0.0001). No change was detected in ECV-304 cell line. These data show that calcitriol reduces cisplatin normal dose use and increases its anti-proliferative activity in the T24 cell line and that it can help maintain the viability of the HUVEC healthy cell line.