[Biological behavior of stromal cell-derived factor-1 on migration, adhesion and apoptosis in different kinds of AML...

The study was aimed to investigate the biological behavior of stromal cell-derived factor-1 (SDF-1) in migration, adhesion and apoptosis as well as the related signaling transduction pathways in different kinds of acute myeloid leukemia (AML) cell lines. The expression of surface molecules on AML (KG1a, ML1 and U937) cells were analyzed by flow cytometry. The cell adhesion was detected by MTT assay. The cell migration was checked by transwell assay. Bcl-xl was checked by immunoblotting after activation of phosphionositide-3 kinase (PI3K) in AML cells treated with SDF-1. The results indicated that the expressions of the surface molecules on AML (KG1a, ML1 and U937) cells were different. The list of the expression showed CD34 (KG1a = 95.6%, ML1 = 4.6%, U937 = 4.8%), CD45 (KG1a = 98.3%, U937 = 97.5%, ML1 = 17.8%), CXCR4 (ML1 = 85.4%, U937 = 43.6%, KG1a = 3.8%), ICAM (KG1a = 75.8%, U937 = 41.8% and ML1 = 46.3%). SDF-1 could not upregulate their expression, but could trigger the establishment of polarized morphology of the cells which expressed CXCR4 high. SDF-1 promoted ML1 and U937 cell adhesion to the stroma cells (HS5, HS27), stimulated PI3K in the cells. It was also confirmed that SDF-1 could increase the leukemic cell survival by stimulate this pathway. After addition of wortmaninn or PTX, the cell death increased. It is concluded that the SDF-1 increases the leukemic cell adhesion, migration and survival by stimulating the PI3K pathway. These functions can be depressed by the PI3K inhibitor and also the inhibitor of G protein as well.