RESUMEN
Photothermal therapy (PTT) is a highly effective anti-tumor method. However, when laser radiation was used to ablate tumors, it usually triggers a series of inflammatory reactions, promoting the further development of tumors and affecting the effect of anti-tumor therapy. Therefore, it is an effective method to improve the anti-tumor effect by suppressing the inflammatory response through the precise targeted delivery of anti-inflammatory drug while realizing the photothermal treatment of tumors. To this end, the redox-responsive linker 3,3'-dithiodipropionic acid was used to bond the classic hydrophobic anti-inflammatory drug 18β-glycyrrhetinic acid (18β-GA) and the hydrophilic fragment methoxy-polyethylene glycol (mPEG-NH2) to obtain redox-responsive amphiphilic polymer PEG-DA-GA in this study. Then, photothermal agent IR-780 was encapsulated to prepare redox-responsive polymer micelle PDG/IR-780 NPs. The PDG/IR-780 NPs exhibited uniform particle size of 80.2 ± 5.3 nm and the polydispersity index (PDI) was 0.215 ± 0.079. All animal experiments followed the ethical requirements formulated by the Ethics Committee of Sichuan University. The results showed that PDG/IR-780 NPs could respond to the abundant glutathione (GSH) in tumor cells to promote the disintegration of nanoparticle and the release of 18β-GA, thus significantly improved the killing efficiency on 4T1 cells, when compared with the non-redox-responsive control PSG/IR-780 NPs. When the concentration of 18β-GA was 50 μg·mL-1, the cell viability of 4T1 cells in the PDG/IR-780 NPs group was only (19.29 ± 1.80) %, which was significantly lower than the result of in PSG/IR-780 NPs group (29.30 ± 1.37) %. The results of frozen sections of tumor tissues showed that the designed PDG NPs can promote the tumor-targeted distribution of drugs compared with the free drug group. Eventually, PDG/IR-780 NPs achieved wonderful anti-tumor efficacy on 4T1 triple-negative breast cancer model, revealing the new possibility of the combined therapy strategy of photothermal and anti-inflammatory therapy.
RESUMEN
Objective To prepare and characterize a thermo-sensitive liposomes co-loaded with IR-780 and doxorubicin (D0X). Methods Membrane hydration method and ammonium sulfate gradient method were used to prepare IR-780/D0X thermo-sensitive liposomes (DITSL). The particle size, zeta potential and polydispersity coefficient (PDI) of liposomes were measured by Malvern laser particle size analyzer, and the drug release characteristic of DITSL induced by laser was also detected. Results DITSL loading both IR-780 and D0X was successfully prepared. The encapsulation efficiency of IR-780 and D0X was (94.47 ± 8.57) % and (92.52 ± 7.61)%, respectively; the average particle size was (138.98 ± 8.74) nm, with slight negative potential; the PDI was 0.32 ± 0.02. The drug release rate of DITSL was about 80.1% after laser radiation (0. 8 W/cm2, 5 min) and the highest temperature of DITSL was 54.2°C. Conclusion The prepared DITSL has high drug encapsulation efficiency, appropriate particle size, high photo-thermal conversion efficiency, good temperature sensitivity and laser-induced thermal drug release property, which lays a foundation study for the combination treatment of tumors with photo-thermal therapy and chemotherapy.
RESUMEN
The tumor targeted fluorescent magnetic IR780-Fe3 O4 nanoparticles were prepared for separation and detection of circulating tumor cells ( CTCs ) . These IR780-Fe3 O4 nanoparticles were characterized by electron microscopy, fluorescence spectrometer, and superconducting quantum interferometer. The targeting effect of IR780-Fe3 O4 nanoparticles was analyzed on the tumor and normal cells by confocal microscope and flow cytometry, and the confocal microscope was used to target the location of IR780-Fe3 O4 nanoparticles in MCF-7 cells. The standard curve was drawn and evaluated accorded to the IR780-Fe3 O4 nanoparticles fluorescence intensity of tumor cells after incubation. The results showed that IR780-Fe3 O4 nanoparticles could target a variety of CTCs. Furthermore, cellular localization experiment proved that IR780-Fe3 O4 nanoparticles could target the mitochondria of tumor cells. With the method of coupling magnetic Fe3 O4 nanoparticles, IR780 could well distinguish the tumor and normal cells, which could be used for separating and detecting the CTCs in simulated blood.
RESUMEN
The tumor targeted fluorescent magnetic IR780-Fe3 O4 nanoparticles were prepared for separation and detection of circulating tumor cells ( CTCs ) . These IR780-Fe3 O4 nanoparticles were characterized by electron microscopy, fluorescence spectrometer, and superconducting quantum interferometer. The targeting effect of IR780-Fe3 O4 nanoparticles was analyzed on the tumor and normal cells by confocal microscope and flow cytometry, and the confocal microscope was used to target the location of IR780-Fe3 O4 nanoparticles in MCF-7 cells. The standard curve was drawn and evaluated accorded to the IR780-Fe3 O4 nanoparticles fluorescence intensity of tumor cells after incubation. The results showed that IR780-Fe3 O4 nanoparticles could target a variety of CTCs. Furthermore, cellular localization experiment proved that IR780-Fe3 O4 nanoparticles could target the mitochondria of tumor cells. With the method of coupling magnetic Fe3 O4 nanoparticles, IR780 could well distinguish the tumor and normal cells, which could be used for separating and detecting the CTCs in simulated blood.