Dr. Stephanie Xie is fascinated with the persistence of long-term hematopoietic stem cells (LT-HSCs) for lifelong blood production. Her challenge as a stem cell biologist is to understand the molecular programs in place to balance dormancy with cellular activation to maintain self-renewal and differentiation in LT-HSCs. Some of these include cell cycle regulation, the interplay of transcriptional, epigenetic and signaling pathways, and metabolism. Teasing out these regulatory systems may help us better understand what causes malignancy like acute myeloid leukemia (AML). Recent work in the field has also revealed that stemness underlies AML and determinants of stemness are prognostic for patient survival. What continues to be challenging is that AML is highly heterogeneous and our current treatments fail to adequately treat the leukemia stem cells (LSC), which are typically the source of relapse. Dr. Xie has identified a particular class of lipids, sphingolipids, that intersects with stemness and proteostasis quality control programs to regulate cell fate in primary human LT-HSC and this differs in patient LSCs. Lipids are understudied in LSCs despite the recognition that cellular metabolism is a hallmark of cancer. Dr. Xie believes that understanding lipid metabolism in stem cells can be very powerful and have great promise to yield strategies for targeting stemness in AML and thus prevent relapse.