found that resistant monocytes (CD45-bright/SSC-high/CD117-/CD11b+/CD68+) differentiated after drug treatment showed a significantly different response from typical FAB-M0/M1/M2 bone marrow cells (CD45-med/SSC-low/CD117+/CD11b-/CD68-) in AML patients. The gene discussed is PTPRC; the disease is acute myeloid leukemia.