Loss of PTEN contributes to the activation of Akt in a subset of cases. Western blot analysis for PTEN was performed for all MCL cases and cell lines. SUDHL-1 (S) served as positive control. PTEN expression was decreased in 5 of 17 (29%) cases with activated Akt, including 4 high-expressing blastoid MCL (cases 8, 10, 11, 12) and 1 low-expressing typical MCL (case 24). In contrast, 1 of 14 cases without detectable Akt activation (case 25) showed decreased expression of PTEN. Actin is shown as loading control.