NGF and acute lymphoblastic leukemia: The levels of pro-BDNF (1.14 pg/mL), BDNF (0.70 pg/mL), and NGF (1.66 pg/mL) analyzed at ALL diagnosis were significantly lower than pro-BDNF (11.07 pg/mL), BDNF (6.87 pg/mL), and NGF (6.84 pg/mL) levels assessed in HI samples (Figure 1, Figure 2 and Figure 3).