TNFR2 predicts SM sensitivity. (A) Sensitivity of primary ALL samples in different risk categories, according to risk stratification in the AIEOP-BFM 2000 study, to birinapant. Numbers are cases with IC₅₀ < 100 nM and the total analyzed cases. TNFR2 (TNFRRSF1B) expression²⁰  from 17 primary samples correlated with the response (IC₅₀) to birinapant (B) and LCL161 (C). TNFR2 (D) and TNFR1 (E) expression by quantitative real-time PCR from 12 responsive PDX samples (birinapant IC₅₀ ≤ 100 nM) and 22 nonresponsive PDX samples (birinapant IC₅₀ > 100 nM). MR/HR, medium risk/high risk; SR, standard risk; VHR, very high risk.