Coexpression of S1PR1 and phospho-STAT3 in ABC-DLBCL patient tumor cells. (A) Left panel: immunofluorescent staining of S1PR1 (green) and phospho-STAT3 (red) in ABC-DLBCL patient tumor tissue sections. Shown are 3 independent ABC-DLBCL patient tissue sections, representing 10 tested patient samples. Scale bar represents 50 μm. Right panel: quantification of 10 tested patient tissue sections for percentages of overlapping red (p-STAT3) and green (S1PR1) channels, shown as Manders colocalization coefficients M1 (p-STAT3 to S1PR1) and M2 (S1PR1 to p-STAT3), respectively. For each patient tumor section, 10 random fields were chosen to calculate M1 and M2, valued and normalized as mean, which is represented by a dot. One tumor tissue section from each of the 10 patients was analyzed. (B) Immunohistochemistry staining of S1PR1 and phospho-STAT3 of the same region, using consecutive ABC-DLBCL patient tissue sections. Scale bar represents 50 μm.