TOX inhibition impairs the tumor-forming ability of CTCL cells in vivo. (A) Tumor volume comparison between Hut78 and HH mice injected with 1 million TOX-sh cells (n = 12) or control (CTR) cells (n = 6). Mice were monitored for local tumor formation 3 times a week, and tumor sizes were measured with a glide caliper. Tumor volume was calculated using the formula (length [mm] × width [mm]²) ÷ 2. (B) Gross appearances of mice representative of each injection group (i), appearances of tumor or normal skin (Hut78 TOX-sh) from representative mice (ii), H&E staining of tissue sections from corresponding tumors or normal skin (iii), and immunohistochemistry staining of human CD3 from corresponding tumors or normal skin (iv). Bars represent 1 cm (Bi-ii), 200 μm (Biii-iv), and 25 μm (Biii-iv insets).