Synergistic effects of magnetic drug targeting using a newly developed nanocapsule and tumor irradiation by ultrasound on CT26 tumors in BALB/c mice

The aim of the current study was to magnetically target the 5-fluorouracil (5-Fu) loaded magnetic poly lactic-co-glycolic acid (PLGA) nanocapsules towards CT26 colon tumor model in BALB/c mice. In addition, we ultrasonicated the tumors impregnated by nanocapsules with the goal of aiding them in magnetic drug targeting (MDT) procedure. Newly synthesized 5-Fu-loaded PLGA magnetic nanocapsules were characterized. Various treatment modalities with the use of nanocapsules, magnetic fields, and ultrasound were applied to the tumors and appropriate controls were considered. Magnetic resonance imaging (MRI) and Prussian blue (PB) staining were performed to analyze the distribution of nanocapsules within the CT26 tumor. Finally, anti-tumor and pro-apoptotic effects of each treatment modality on CT26 tumors were investigated. The effective diameter of nanocapsules was approximately 70 nm. The histological staining of the tumor tissue with PB as well as MRI revealed a broad distribution of magnetic nanocapsules within the tumor and confirmed the targeting of nanocapsules to the tumors. Anti-tumor studies demonstrated that the combination of nanocapsules-MDT-ultrasound effectively inhibits the growth of CT26 tumors compared with injection of 5-Fu alone (P < 0.01). The present study exhibits potentials of the newly synthesized magnetic nanocapsule and suggests that the combination of MDT and ultrasound might help this new nanotechnology-based cancer chemotherapy agent in vivo. This journal is © The Royal Society of Chemistry 2015

Evaluation of nonlinear optical behavior of mouse colon cancer cell line CT26 in hyperthermia treatment

Hyperthermia treatment can induce component changes on cell. This study explored the potential of Z-scan to improve accuracy in the identification of subtle differences in mouse colon cancer cell line CT26 during hyperthermia treatment. Twenty-one samples were subjected individually to treatment of hyperthermia at 41, 43, and 45 °C. Each hyperthermia treatment was done in six different time (15, 30, 45, 60, 75, and 90 min). Two optical setups were used to investigate the linear and nonlinear optical behavior of samples. Prior to the Z-scan technique, all samples were fixed with 1 mL of 5 paraformaldehyde. The linear optical setup indicated that extinction coefficient cannot monitor cell changes at different treatment regimes. But the nonlinear behavior of CT26 in all hyperthermia treatment regimens was different. By increasing the time and/or temperature of hyperthermia treatments, change in the sign of nonlinear refractive index from negative to positive occurred in earlier time intervals. This phenomenon was seen for 41, 43, and 45 °C in 75, 60, and 45 min, respectively. The results showed that the Z-scan technique is a reliable method with the potential to characterize cell changes during hyperthermia treatment regimes. Nonlinear refractive index can be used as a new index for evaluation of cell damage. © 2019, Springer-Verlag London Ltd., part of Springer Nature