Compared with either single agent alone, cotreatment with JQ1 and ibrutinib exerts superior in vivo anti-MCL activity against Mino xenografts. (A) NOD/SCID mice (n = 8 per cohort) were injected with Mino cells and monitored for 7 days. Following engraftment, mice were treated with JQ1 and/or ibrutinib for 3 weeks as described in supplemental Methods. Survival of the mice is represented by a Kaplan–Meier plot. Vehicle vs JQ1, P = .003, Student t test; vehicle vs ibrutinib, P = .0204, Student t test. Mantel–Cox rank sum of all groups, P .0013. (B) Immunoblot analyses conducted on the spleen and BM from NOD/SCID mice injected with Mino cells as above, and treated with JQ1 and/or ibrutinib for 1 week. Vertical line(s) have been inserted to indicate a repositioned gel lane. Ibr, ibrutinib; Veh, vehicle.