Figure 4.

Peritoneal tumors of SKOV-3 were induced as described in Materials and Methods, and similar sized tumors (approximately 3∼5 mm in diameters) were soaked in 50 mM DOX diluted in 4 ml of HBSS buffer with unstimulated (A) or PMA-stimulated (B) neutrophils in 15 ml tube. In (C), DNase I (1000 u/ml) was added with PMA-stimulated neutrophils at the start of the experiment. After 3 h, the tumors were taken out, fixed with dry-iced acetone and 10-μM cryostat sections of post-fixed frozen samples were created. After the counterstaining the nuclei with DAPI, the infiltration of DOX from the tumor surface was evaluated with the detection of autofluorescence under fluorescence microscopy (BZ8000; Keyence, Osaka, Japan). Figures show the merged images for DOX (red) and DAPI (Blue).