X-ray-induced nanoparticle-based photodynamic therapy of cancer.
OBJECTIVE
In this study, Ce(3+)-doped lanthanum(III) fluoride (LaF3:Ce(3+)) nanoparticles were synthesized by a wet-chemistry method in dimethyl sulfoxide (DMSO) and their application as an intracellular light source for photodynamic activation was demonstrated.


METHODS
The LaF3:Ce(3+)/DMSO nanoparticles have a strong green emission with a peak at approximately 520 nm, which is effectively overlapped with the absorption of protoporphyrin IX (PPIX). The nanoparticles were encapsulated into poly(D,L-lactide-co-glycolide (PLGA) microspheres along with PPIX. Upon irradiation with x-rays (90 kV), energy transfer from the LaF3:Ce(3+)/DMSO nanoparticles to PPIX occurs and singlet oxygen is generated for cancer cell damage.


RESULTS
The LaF3:Ce(3+)/DMSO/PLGA or LaF3:Ce(3+)/DMSO/PPIX/PLGA microspheres alone caused only sublethal cytotoxicity to the cancer cells. Upon x-ray irradiation, the LaF3:Ce(3+)/DMSO/PPIX/PLGA microspheres induced oxidative stress, mitochondrial damage and DNA fragmentation on prostate cancer cells (PC3).


CONCLUSIONS
The results indicate that x-rays can activate LaF3:Ce(3+) and PPIX nanocomposites, which can be a novel method for cancer destruction.
Department of Physics & the Center for Security Advances via Applied Nanotechnology, The University of Texas at Arlington, TX 76019-0059, USA.
Xiaoju
X
Zou
Mingzhen
M
Yao
Lun
L
Ma
Marius
M
Hossu
Xiumei
X
Han
Petras
P
Juzenas
Wei
W
Chen
D045744:Cell Line, Tumor; D004735:Energy Transfer; D005456:Fluorescent Dyes; D006801:Humans; D053758:Nanoparticles; D009369:Neoplasms / Q000188:drug therapy* / Q000473:pathology; D010778:Photochemotherapy; D014965:X-Rays
D005456:Fluorescent Dyes
LaF3:Ce3+; cancer; energy transfer; luminescence; nanoparticle; photodynamic therapy; photosensitizer; prostate cancer; singlet oxygen; treatment