Hyperactivation of MAPKs in HH. Proteins extracted from HH and control tissue specimens were analyzed by immunoblotting with anti‐active JNK (pJNK), anti‐active p38 MAPK (p‐p38), anti‐active ERK (pERK), and anti‐total ERK, respectively (A). Densitometric analysis results of immunoblotting data of anti‐pJNK (B), anti‐p‐p38 (C), anti‐pERK (D), and anti‐ERK (E), respectively, from 14 HH and eight controls are shown. *P < 0.05; **P < 0.01.