Finally, BM CD26+ LSCs appeared to decrease substantially during a successful treatment with TKIs indicating that CD26 could also be a good predictive biomarker for monitoring CML patients during therapy (20) and that flow cytometry approach could be a useful tool for the identification of CML LSCs on BM samples by using a CD45+/CD34+/CD38−/CD26+ panel as a strict gating strategy (18, 20). The gene discussed is PTPRC; the disease is chronic myelogenous leukemia, BCR-ABL1 positive.