FZD4 and acute myeloid leukemia: On the other hand, several studies reported the upregulation of Wnt elements in primary samples of AML patients; some examples are the gene overexpression of ligands (such as WNT1, WNT2B and WNT10B) and transcription factors (such as LEF-1), or the protein overexpression of receptors (such as FZD4) [52,53,54,55].