CD34 staining of sections from tumors that received (A) vehicle plus light exposure, (B) blank nanoparticles plus light exposure, (C) doxorubicin nanoparticles plus light exposure, (D) methylene blue nanoparticles plus light exposure, (E) doxorubicin and methylene blue in solution plus light exposure, (F) nanoparticles loaded with doxorubicin and methylene blue without light exposure, and (G) nanoparticles loaded with methylene blue and doxorubicin plus light exposure. Images were acquired at 400× magnification.