Increased TNF/NGF Receptor Expression on BCP-ALL Blasts Carrying the Prognostically Favorable TEL-AML Rearrangement.

TEL-AML the most common genetic alteration in childhood precursor B (BCP)-ALL is associated with a favorable prognosis yet the underlying mechanism remains largely unknown. Among the tumor necrosis factor (TNF) receptors CD40 is a key regulator of B cell maturation while nerve growth factor receptor (NGFR), CD27 and CD95 have been implicated in cell cycle arrest and blast apoptosis. Here we prospectively assessed baseline surface expression of the different TNF receptors and the costimulatory molecules CD70, CD80 and CD86 on primary BCP-ALL blasts in a pediatric cohort of TEL-AML positive (n=29) and negative patients (pts) (n=89) treated according to the CoALL06-97 protocol. In the TEL-AML positive subgroup, the percentage of blasts positive for CD40 (median; interquartile range: 100%, 100–100% vs. 82%, 56–97%; p