MSLN and acute myeloid leukemia: identified SPAG6, along with chemokine C-C motif ligand 23 (CCL23), mesothelin (MSLN), suppression of tumorigenicity 18 (ST18), G antigen family D2 (GAGED2), Wilms tumor gene (WT1), and preferentially expression antigen in melanoma 9 (PRAME9), as an MRD marker in AML monitoring.