Role of sphingosine-1-phosphate signaling in the proliferation of breast cancer BT549 cells
Objective To study the role of sphingosine-1-phosphate(S1P)signal on the proliferation of breast cancer BT549 cells.Methods Cells were divided into control group and experimental group,experimental group were treated with 0.1,1.0,10.0 μmol·L-1 S1P receptor agonist SEW2871 for 72 h.Control group was cultured with 0.1%fetal bovine serum.Cell proliferation was detected by methyl thiazolyl tetrazolium(MTT)assay.Cell models of overexpressing S1P receptors in BT549 were divided into three groups:blank plasmid group(LUC),wild type S1P receptor overexpression group(WT),S1P receptor phosphorylation site mutation overexpression group(MUT);the proliferation ratio was detected by MTT,the number of cell clones was counted by colony formation experiment.S1P antagonist W146(10 μmol·L-1)and protein kinase(AKT)signaling inhibitor MK2206(90 nmol·L-1)were used to detect the role of S1P signaling in the proliferation of breast cancer cells.The expression of phosphorylate signal transducer and activator of transcription 3(p-STAT3),c-Myc proteins were detected by Western blot.Results The growth ratio of BT549 cells in control group and 0.1,1.0,10.0 μmol·L-1experimental groups were 1.00±0.03,1.13±0.06,1.06±0.10 and 1.07±0.03,0.1 μmol·L-1 SEW2871 promot the cell proliferation(P<0.05).Compared between WT group,MUT group and LUC group,the growth rate and the number of clonal colonies were increased after overexpression of S1P receptor(all P<0.05).The growth ratio of BT549 cells after treatment with W146 and MK2206 in the LUC group,WT group and MUT group were 1.25±0.12,1.31±0.03,1.43±0.14 and 0.87±0.15,0.77±0.03,0.88±0.02.Compared between MUT group,WT group and corresponding DMSO group,the differences were statistically significant(all P<0.01).The number of cell clony formation number after treatment with W146 were 65.65±5.12,141.48±5.63 and 93.64±5.14;compared between MUT,WT group and corresponding DMSO group,the differences were statistically significant(all P<0.05).The relative protein expression levels of p-STAT3 in LUC group,WT group and MUT group were 0.67±0.04,0.69±0.08 and 0.81±0.06,the relative protein expression levels of proto-oncogene c-Myc were 1.69±0.03,0.70±0.10 and 0.67±0.07,compared between WT group,MUT group and corresponding DMSO group,the difference was statistically significant(P<0.05).Conclusion S1P signaling can promote proliferation in breast cancer BT549 cells,and the mechanism could be related to AKT and STAT3 signaling pathway.
sphingosine 1-phosphate receptor agonist and antagonistprotein kinase B inhibitorsphingosine 1-phosphate signalingbreast cancer cellproliferation