Fig. 6

Characteristics and antitumor effects of Dc-NBs in PCa cells in vitro. A Schematic illustration of Step-wise fabrication of bowl-like structured OA-Gd/PDA NPs. B TEM images of the bowl-like structured OA-Gd/PDA NPs (named as NBs in this study) (upper left panel); Elemental mapping of NBs (lower left and right panel). C SEM image of the NBs. D The UV-vis absorbance spectra of NBs. E - F Photothermal temperature changes of NBs with different concentrations (E) and irradiation power densities (F). G Thermal images of water and NBs solution with different concentrations under NIR laser irradiation (808 nm). H Temperature change profiles of NBs with 4 times NIR irradiation cycle. I Heating and cooling curves (gray) and time constant (τs) for heat transfer from the system (pink). J Loading efficiency and encapsulation efficiency and of DTX in NBs nano-carrier. K Zeta potential of the D-NBs and circBNC2 loaded D-NBs. L CCK-8 assay analyzed cell viability of RWPE-1 and DU145 treated with saline (Ctrl) or different concentrations of NBs. M Analysis of cell viability of DU145 cells by CCK-8 assay, upon treatment with saline (Ctrl), DTX loaded NBs (D-NBs), DTX and circBNC2 co-loaded NBs (Dc-NBs) or Dc-NBs combined photothermal therapy (PTT) (Dc-NBs + PTT). N Western blotting results revealed the expression of ACSL6, ACSL4, COX2, NOX1, GPX4, FTH1 in DU145 cells treated with different treatment, including Ctrl, D-NBs, Dc-NBs or Dc-NBs + PTT. O The level of ROS was detected in DU145 cells by CLSM treated with different treatment as indicated. Scale bar = 50 μm. P  In vivo fluorescence images of DU145-tumor-bearing mice at various time points after tail vein injection of Cy5.5 loaded NBs and ex vivo fluorescence imaging of the tumor and the major organs at 48 h. ns, no significance; *P < 0.05; **P < 0.01; ***P < 0.001