STAT5B and erythroleukemia: In human erythroleukemia cells, which are homozygous for JAK2 V617F and harbor p53 M133K mutation, downmodulation of p53 or inhibition of STAT5 activation prevents induction of LPP and similarly regulated genes; recruitment of p53 M133K is dependent on STAT5 chromatin binding, while downmodulation of p53 still allows STAT5 chromatin binding.