NK314 inhibits cell growth of ATL cell lines. (A) Structure of NK314. (B-E) Inhibition of cell growth of ATL-related cell lines MT-1 (B), KOB (C), MOLT4 (D), and normal PBMCs (E) by treatment with NK314 or etoposide. NK314 (●) or etoposide (♦) were added at various concentrations in culture media, and cell growth rates were determined by trypan blue staining 48 hours after treatment. The relative ratio of cell growth is shown; values are mean ± SD of triplicate analyses.