Immunohistochemistry was performed on 4 μm sections that were
cut from FFPE (formalin-fixed, paraffin-embedded) blocks. Sections were then
deparaffinised with xylene and rehydrated through graded ethanol. Antigen
retrieval was achieved with a pH 9.5 Nuclear Decloaker (Biocare Medical) in a
Decloaking pressure cooker at 95°C for 40 min. Tissue sections were then
treated with 3% hydrogen peroxide (LOT 161509; Fisher Chemical) and with
Background Sniper (Biocare Medical, Concord, CA, USA) to reduce nonspecific
background staining. Primary antibody for p53 (Cell Signaling, 2527) was applied
in a 1:150 dilution for 80 min followed by detection with the MACH 3 Rabbit HRP-
Polymer Detection kit (Biocare Medical). Visualization was achieved using VECTOR
NovaRED (SK-4800; Vector Laboratories, Inc.) as chromogen. Lastly, sections were
counterstained with Tacha's Automated Hematoxylin (Biocare Medical).
cut from FFPE (formalin-fixed, paraffin-embedded) blocks. Sections were then
deparaffinised with xylene and rehydrated through graded ethanol. Antigen
retrieval was achieved with a pH 9.5 Nuclear Decloaker (Biocare Medical) in a
Decloaking pressure cooker at 95°C for 40 min. Tissue sections were then
treated with 3% hydrogen peroxide (LOT 161509; Fisher Chemical) and with
Background Sniper (Biocare Medical, Concord, CA, USA) to reduce nonspecific
background staining. Primary antibody for p53 (Cell Signaling, 2527) was applied
in a 1:150 dilution for 80 min followed by detection with the MACH 3 Rabbit HRP-
Polymer Detection kit (Biocare Medical). Visualization was achieved using VECTOR
NovaRED (SK-4800; Vector Laboratories, Inc.) as chromogen. Lastly, sections were
counterstained with Tacha's Automated Hematoxylin (Biocare Medical).