Abstract: Abstract Objective: To explore the effects and mechanisms of monoclonal antibody against CD44 (A3D8) on proliferation in sphere-forming cells from solid tumor of ovarian cancer. Methods: MTS assay was used to evaluate cell proliferation; flow cytometry was used to analyze cell cycle distribution; DNA damage was measured by comet assay; expression of CDK2 and cyclinA proteins after treatment with A3D8 was evaluated by western blot assay. Results: A3D8 could inhibit the proliferation of sphere-forming cells from solid tumor of ovarian cancer; the inhibition was in dose- and time-dependant manner; compared with treatment with DDP alone, the inhibition rate caused by A3D8 combined with DDP was increased significantly ;The percentage of cells in S phase significantly increased after treatment with A3D8;DNA was damaged after treatment with A3D8 for 24h; western blot analysis demonstrated that the expression of CDK2、cyclinA proteins was suppressed significantly. Conclusion: A3D8 could inhibit the proliferation of sphere-forming cells from solid tumor of ovarian cancer, and the inhibiting effect was probably carried out by arrest of cell cycle.

Key words: monoclonal antibody against CD44 (A3D8), sphere-forming cells from solid tumor of ovarian cancer, cell proliferation