Fig. 1

Detection of the expression of STAT3 (cytoplasmic) and phospho-STAT3 (Tyr705) by immunohistochemistry in formalin-fixed and paraffin-embedded (FFPE) tissue of feline injection site sarcomas. Images A-D represent the grade 0–3 expression of panSTAT3, respectively. Images E-H represent the grade 0–3 expression of phospho-STAT3 (Tyr705), respectively. The detailed grading criteria is as follows. Count 10 HPF for each section (at least 1000 cells), 0 = negative; 1 = less than 10% cells positive; 2 = 10–50% cells positive; 3 = more than 50% cells positive Scale bars = 500 μm; inset: scale bars = 50 μm