Patients with cGVHD have increased B-cell signaling associated with metabolic activation and survival. (A) Phosphorylation of ERK (pERK at Thr 202 and Thr 204) and AKT (pAKT at S473) measured by immunoblot analysis of peripheral B cells from patients with cGVHD (+cGVHD) and without cGVHD (−cGVHD). Expression was controlled by reprobing with the respective nonphosphospecific protein. (B) Normalized B-cell expression of phosphorylated ERK (left) and phosphorylated AKT (right) in patients without cGVHD (−cGVHD) and with cGVHD (+cGVHD). Data are median ± range, pooled from 5 independent experiments. −cGVHD, n = 9 or 10. +cGVHD, n = 8-10. *P = .021 (unpaired 2-tailed t test with Satterthwaite correction). #P = .009 (unpaired 2-tailed t test with Satterthwaite correction). (C) Isoforms of Bim (Bim _EL, Bim _L, and Bim _S) analyzed by immunoblot analysis of peripheral B cells from patients without cGVHD (−cGVHD) and with cGVHD (+cGVHD). Expression was controlled by reprobing for β-actin. (D) Normalized B-cell expression of the long and short isoforms of Bim in patients without cGVHD (−cGVHD) and with cGVHD (+cGVHD). Data are median ± range from 3 independent experiments. −cGVHD, n = 11. +cGVHD, n = 6. *P = .017 (unpaired 2-tailed t test with Satterthwaite correction).