Philadelphia chromosome-positive leukemia stem cells in acute lymphoblastic leukemia and tyrosine kinase inhibitor therapy

Figure 1 Effect of tyrosine kinase inhibitor on Philadelphia chromosome-positive acute lymphoblastic leukemia and their stem cell counterparts. Therapy with tyrosine kinase inhibitor (TKI) results in the depletion of cycling leukemia cells (of which progenitor cells) without eliminating the Leukemia stem cells (LSCs), then the latter can regenerate the tumor after that therapy is halted. This seems to explain why TKI treatment needs to be chronic and why future drug development needs to be focused on agents that stike at the core of tumors by destroying stem cells.