Abstract: Abstract Objective: To explore the effects and mechanisms of A3D8(mAb) against CD44 on proliferation and apoptosis in three kinds of sphere-forming cells of ovarian cancer. Methods: The MTS assay was used to evaluate the cell proliferation. The PI staining and flow cytometry was used to analyze the cell cycle distribution. Annexin V-FITC/PI apoptosis detection kit was used to analyze cell apoptosis. Rhodamine123 apoptosis detection kit was used to detect the change of mitochondrial transmembrane potential (ΔψM). Western blotting assay was used to detect the CDK2,cyclinA,Bcl-2 and caspase-3 protein levels. Results: A3D8 inhibited the proliferation in three sphere-forming cells of ovarian cancer, the inhibition was in concentration-and time-dependant manner. A3D8 could cause S arrest with G0/G1 decrease via p21/CDK2/cyclinA pathways. A3D8 can increase the apoptosis rates of three kinds of cells, compared with DDP treatment alone, the apoptosis rates caused by A3D8 combined with DDP was increased significantly.Meanwhile A3D8 can lead ΔψM to decrease, CDK2,cyclinA,Bcl-2 protein level decrease and caspase-3 increase in above three kinds of sphere-forming cells. Conclusion: A3D8 inhibit the proliferation in three sphere-forming cells of ovarian cancer probably by the cell cycle arrest via p21/CDK2/cyclinA pathways and increase the apoptosis rates via mitochondrial pathways.

Key words: anti-CD44 monoclonal antibody A3D8, sphere-forming cells of ovarian cancer, cell proliferation, apoptosis