IRS1 and neuroblastoma: Endogenous IRS-1 expression was increased by DYRK1A to 149.6 ± 4.8% of control (Fig. 1, E and F, lane 2 versus 1; p = 0.0006) and decreased by DYRK1A inhibitor harmine to 74.8 ± 6.1% of control (Fig. 1, E and F, lane 4 versus 3; p = 0.0181) in neuroblastoma SH-SY5Y cells.