FIGURE 1.

OR‐S1 is an effective suppressor of mantle cell lymphoma (MCL) tumor growth in vitro and in vivo. A, The chemical structure of OR‐S1. B, Protocol for the in vivo study of OR‐S1 efficacy of using an MCL patient–derived xenograft (PDX) mouse model. A patient‐derived tumor was xenografted into SCIDbg mice, and after 1 wk vehicle control or 200 mg/kg of ibrutinib or OR‐S1 was orally administered twice a day for 3 wk. C, Tumor burden of mice treated with ibrutinib (left) or OR‐S1 (right) compared with vehicle control. When tumor volumes exceeded 2000 mm³, the mice were euthanized. Data represent the mean of triplicates ± SD. *P <.05. D, E, Growth curves of three MCL cell lines (Mino, JeKo‐1, and REC‐1) treated with OR‐S1 (D) or GSK126 (E). Cell number was calculated on days 3, 7, 10, and 14 (Mino and JeKo‐1), or days 5, 10, and 15 (REC‐1). F, Western blotting for H3 lysine 27 trimethylation (H3K27me3). Cells were treated with vehicle alone or 300 nmol/L OR‐S1 for 5 d, and total histones were extracted in 0.4 N HCl. Band intensity was measured by ImageJ