AR optimization. (A, B, and C): Serial sections of breast cancer FFPE slides
were subjected to AR at different temperatures for immunostaining with
anti-topoI-pS10. (D) CRC FFPE slides were also subjected to immunostaining
with anti-topoI-pS10 without heat-induced AR. (E) The same tissue was
immunostained with anti-topoI-pS10 after heat-induced AR at 100C. The red
box is an enlarged image of the positive area. Scale bar = 100 µm.
Abbreviations: AR, antigen retrieval; FFPE, formalin-fixed paraffin
embedded; topoI-pS10, topoisomerase I phosphorylates at serine 10; CRC,
colon cancer.