CXCR4 and acute lymphoblastic leukemia: Another study found that integrin β1 existed in a multi-protein membrane complex together with the potassium channel protein hERG1 (human Ether-à-go-go-Related-Gene 1) and the C-X-C chemokine receptor type 4 (CXCR4) and that stromal cell-mediated chemoresistance in ALL cells was overcome by hERG1 blockade or inhibition of the CXCR4/CXCL12 axis (58).