Cluster of differentiation 96 as a leukemia stem cell-specific marker and a factor for prognosis evaluation in leukemia

Resistance to chemotherapy is a major challenge for leukemia treatment. It has been suggested that leukemia stem cells (LSCs), a small pool of self-renewing leukemic cells, play important roles in development of chemotherapy resistance. The expression of cluster of differentiation 96 (CD96), a potential marker for LSCs, was investigated in CD34+CD38− cells of 105 acute leukemia (AL) patients by flow cytometry. The data showed that all the CD34+, CD34+CD38− and CD34+CD38−CD96+ proportions were much higher in AL compared to the normal control (P 15% CD34+CD38− cells achieved complete remission (CR), suggesting that as an LSC-rich population, the amount of CD34+CD38− cells may not be positively associated with the proportion of refractory LSCs. The mean percentage of the co-presence of CD96 expression itself was similar in AML patients with CR and non-CR (P>0.05). However, the CR rate was significantly higher in the AML population with <10% CD96 expressed, which indicated that a distinct sub-group of CD34+CD38−CD96+ cells may still contribute to the drug resistance or poor prognosis.