Investigation of the treatment efficacy of zinc phosphateloaded cisplatin in MDR1 gene inhibited head and neckcancer cell line

In this thesis study, the treatment efficacy of cisplatin (ZnP+SiO2+CIS) loaded onto ZnP-coated SiO2 nanoparticles produced by green synthesis method by inhibiting MDR1 gene with siRNA in FaDu cell line was evaluated. Synthesized nanoparticles were structurally and morphologically characterized by Zeta Potential, XRD, FTIR, SEM and TEM analyses. Drug loading capacity and loaded drug amount were determined by HPLC analyses; release profile of cisplatin was examined in detail by in vitro release tests performed under different pH conditions. In cell culture experiments, IC50 value of ZnP+SiO2+CIS application was found as 15 µg/mL in FaDu cell line. While it was determined that MDR1 gene silencing alone had a limited effect on cell viability, ZnP+SiO2+CIS application caused a significant decrease in cell viability and provided a significant increase in treatment efficacy. In addition, RT-PCR and Western blot analyses revealed detailed molecular effects of MDR1 inhibition and nanoparticle treatments on cell death, proliferation and signal transduction pathways. The obtained data highlighted the potential of nanoparticleassisted chemotherapy approaches to overcome multidrug resistance.