The relationship between tumor stem cells marker CD90 and resistance to cisplatin in human lung adenocarcinoma A549 cells

Objective: To observe the relationship between stem cells marker CD90 and CDDP (cisplatin) resistance in lung adenocarcinoma A549 cells, and to explore whether CD90 is a marker of lung cancer stem cells. Methods: Self-renewal abilities of A549 and A549/CDDP cells were detected by sphere-forming assay, CCK-8 (cell counting kit-8) and plate colony-formation assay, respectively. The proportions of CD90＋ in A549 cells, A549/CDDP adherent cells and the spheres cells were measured by FCM (flow cytometry). The CDDP resistance in CD90＋A549 cells and CD90－A549 cells was detected by cytotoxicity experiment. The CDDP resistance in CD90＋A549 cells in vivo was detected by using transplanted tumor in nude mice. Results: As compared with A549 cells, the abilities of sphere formation, proliferation and colony-formation efficiency of A549/CDDP cells were increased (P < 0.01). The proportions of CD90＋ in A549/CDDP adherent cells and the sphere cells were higher than those in the corresponding A549 adherent cells and the sphere cells (P < 0.05). IC50 (half inhibitory concentration) values of CDDP in CD90＋A549 and CD90－A549 cells were 8.50 and 1.50 μmol/L, respectively. The tumor xenograft volume of CD90＋A549 cells was larger than that of CD90－A549 cells after treatment with CDDP in nude mice (P < 0.05). Conclusion: A549/CDDP cells show high self-renewal ability and CD90＋ proportion. CD90＋A549 cells have high ability of CDDP resistance. CD90 may be a marker of lung cancer stem cells. DOI:10.3781/j.issn.1000-7431.2013.09.004