Tcl1 and Atm are crucial for growth and proliferation of lymphoma cells in vitro and in vivo. (A) Daudi cells were mock-transfected or transfected with si-TCL1 or si-Scr and then untreated or treated with Kudos 55933 or DMSO. Cells were counted at 24-hour intervals. Results represent the average of 3 independent experiments. (B) Total lysates collected were analyzed by Western blot and tested with indicated antibodies. (C) Graph representing tumor volumes at indicated days during the experiment for the 5 groups indicated (4 mice/group). Tumor size was measured daily until the tumor reached 50 mm3. Then, 5 μg of synthetic si-TCL1or si-Scr diluted in Lipofectamine and with or without Kudos (50 μL total volume) were injected directly into the tumors and at 3, 7, and 10 days. Tumors were measured on the day of the injections and 4 days after the last injection. (D) Total lysates from tumors were analyzed by Western blot and tested with indicated antibodies. (E) Xenograft tumors were weighed. Data are mean ± SEM of 3 independent experiments, and each is measured in triplicate. *P < .05.