Analysis of cell surface and intracellular markers in RHOA-mutated cases. (A) Analysis of cell surface marker in RHOA mutated cases. Expression of PD-1 and FOXP3 (bottom) in the CD4⁺CD25⁺ tumor cell fraction (top) in primary ATLL samples. Results of 3 representative cases are shown. Case ID, type of RHOA mutations, and their VAFs are also indicated. Numbers in boxes show percentage of cells in the indicated fractions. (B) Immunohistochemical analysis of formalin-fixed paraffin-embedded specimens obtained from the lymph nodes of two RHOA-mutated ATLL cases. Representative images of double staining with FOXP3 (intra-nuclei, brown) and PD-1 (cytosol, blue), and single staining with CD25, CD3, CD4, and CD45RO (brown) are shown.