PDLIM2 suppresses tumorigenicity of HTLV-I/Tax both in vitro and in vivo. (A) Rat-1 cells stably expressing GFP, Tax, Tax, and PDLIM2, or Tax and PDLIM2 LIM deletion mutant (ΔLIM) were plated in soft agar for colony formation. Pictures shown here were taken at day 21 after plating. Original magnification: ×100. (B) PDLIM2 wild-type (WT) and knockout (KO) MEFs stably expressing Tax or an empty vector (Vec) were plated in soft agar for colony formation. Pictures shown here were taken at day 21 after plating. Original magnification: ×40. (C) Expression levels of Tax, exogenous PDLIM2 (WT), and LIM deletion mutant (ΔLIM) in Rat-1 stable cells used in panels A and E were examined by IB using Tax and Myc antibodies, respectively. The expression levels of Hsp90 were used as a loading control. (D) Expression levels of Tax in PDLIM2 wild-type or knockout stable cells used in panels B and F were examined by IB using Tax antibody. The expression levels of Hsp90 were used as a loading control. (E) Rat-1 cells stably expressing Tax or Tax/PDLIM2 were subcutaneously inoculated into the right and left hind-back of the same SCID mouse, respectively. Pictures (from left to right) here were taken at days 14, 21, and 28 after inoculation, respectively. Bar represents 1 cm. (F) PDLIM2 WT and KO MEFs stably expressing Tax were subcutaneously inoculated into the right and left hind-back of the same SCID mouse, respectively. The mice were killed at day 21 after inoculation and tumor weights were measured. The data presented are the mean plus or minus standard deviation (n = 15), and P value is .027 (Student t test). (G) The indicated HTLV-I–transformed T-cell lines stably expressing PDLIM2 or an empty vector were subcutaneously inoculated in the postauricular region of SCID mice. The mice were killed at day 21 of postinoculation for tumor evaluation.