IVM of calvarium bone marrow tracked the migratory behavior of acute myeloid leukemia (AML) cells in comparison to T cell acute lymphoblastic leukemia (T-ALL), and demonstrated distinct traits of the lineages in their response to chemotherapy and CXCR4 antagonism, highlighting the importance of carefully evaluating cancer traits in vivo for each tumor type (171). The gene discussed is CXCR4; the disease is acute lymphoblastic leukemia.