Titaniumdioxide mediated sonophotodynamic therapy against prostate cancer

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Oncology

Background:

• Titanium dioxide (TiO2) nanoparticles are utilized in various industries and have potential as sensitizers for cancer therapies.
• Photodynamic therapy (PDT) and sonodynamic therapy (SDT) are emerging cancer treatment modalities.
• Sonophotodynamic therapy (SPDT) synergistically combines PDT and SDT for enhanced therapeutic outcomes.

Purpose of the Study:

• To investigate the antitumor efficiency of TiO2-mediated PDT, SDT, and SPDT against PC3 prostate cancer cells.
• To compare the in vitro efficacy of PDT, SDT, and SPDT using TiO2 nanoparticles.
• To elucidate the apoptotic mechanisms underlying TiO2-mediated SPDT.

Main Methods:

• PC3 prostate cancer cells were incubated with varying concentrations of TiO2 nanoparticles.
• Cells were subjected to ultrasound (US) and/or light irradiation (0.5 W/cm2 and 0.5 mJ/cm2, respectively).
• Cell viability was assessed using MTT assay; apoptosis was analyzed via Propidium iodide and Hoechst 33342 staining and Western blot analysis for apoptosis-related proteins (caspases, PARP, Bax). Oxidative stress markers (MDA, SOD, CAT, GSH) were also evaluated.

Main Results:

• TiO2-mediated SPDT significantly reduced PC3 cell viability compared to PDT and SDT alone.
• SPDT treatment led to increased apoptotic bodies and altered expression of apoptosis-related proteins, including increased caspase-9 and decreased caspase-3, caspase-8, PARP, and Bax.
• Biochemical analysis indicated increased MDA levels and decreased SOD, CAT, and GSH levels post-treatment, suggesting oxidative stress induction.

Conclusions:

• TiO2-mediated SPDT demonstrates significant potential as a novel therapeutic strategy for prostate cancer.
• SPDT induces cancer cell death primarily through the induction of apoptosis.
• TiO2 nanoparticles serve as effective sensitizers for SPDT, highlighting their role in enhancing cancer therapy.