ACKR3 and acute lymphoblastic leukemia: Additionally, high levels of CXCR7 transcripts were found in malignant ALL cells and cell lines and in the T-ALL subtypes [63, 92, 93],, although little surface expression of CXCR7 was detected in mouse Notch1-induced T-ALL cells with high surface levels of CXCR4 [15].