CD26 (dipeptidyl peptidase-4 (DPP4)) is involved in releasing CML LSCs into the bloodstream from the BM through cleaving stromal-derived factor (SDF-1: CXCL12)-CXCR4 (CD184) axis, which can lead to the disruption of interactions within the stem cell niche and spread of the disease regardless of specific niche regulations. The gene discussed is CXCL12; the disease is chronic myelogenous leukemia, BCR-ABL1 positive.