4 6 diamidino 2 phenylindole dapi staining

Gastric paracarcinoma and cancerous tissues from animal models were fixed with 4% paraformaldehyde for 48 h, dehydrated, and embedded in paraffin. The paraffin sections were subjected to antigen retrieval, sealing, incubation with primary antibodies (1:50 dilutions of myeloperoxidase [MPO] [ab90810; Abcam, UK], cit-H3 [ab5103; Abcam], CD66b [ab207718; Abcam], CCDC25 [21209–1-AP; Proteintech, China], and CD31 [ab228968; Abcam]), incubation with secondary antibodies (1:100 dilutions of horseradish peroxidase [HRP]-labeled goat anti-mouse IgG and HRP-labeled goat anti-rabbit IgG), 4′,6-diamidino-2-phenylindole (DAPI) staining (Solarbio Life Science, Beijing, China), coloration, and sealing. The samples were then observed and photographed using a confocal microscope (LSM800; Zeiss, Germany).

SAHF are specialized domains of facultative heterochromatin senescent cells. HCC cells were inoculated onto a 15-mm confocal dish (2 × 10⁴ cells per well). The cells were fixed in 4% paraformaldehyde, and dyed utilizing 4’,6-diamidino-2-phenylindole (DAPI) staining (Solarbio, China) lasting 10 min to investigate SAHF. The images were captured under a confocal microscope (Leica, Germany). The SAHF-positive percentage was quantified with ImageJ software.