Abstract: Objective To explore the role and mechanisms of ω-3 polyunsaturated fatty acids(ω-3PUFA)alone or in combination with dexamethasone(DEX)in inducing cell apoptosis and anti-proliferation in multiple myeloma(MM).Methods DEX resistance MM cell line MM1R were treated with different concentrations of Eicosapentaenoic acid(EPA)or Docosahexaenoic acid(DHA)alone or in combination with DEX for 24hrs or 48hrs.Cell proliferation was detected by MTT.Cell cycle and apoptosis were measured by flow cytometry.The levels of apoptosis related proteins were analyzed by Western blot.Results The proliferation of MM1R was inhibited by different concentrations(10,20,50,100 μM)of EPA or DHA alone or in combination with 10 μM DEX in a dose-and time-dependent manner.Inhibition effect was significantly higher in combinative groups than in single agent groups(P＜0.05).The percentage of G₀/G₁ phase and cell apoptosis rate in MM1R treated with different concentrations of EPA or DHA alone was increased in a dose-dependent manner,and being significantly higher in combinative groups than in single agent groups(P＜0.05).The expressive levels of cleaved caspase-3 and Bax were up-regulated,while pro-caspase-3 and BCL-2 were down-regulated in a dose-dependent manner.Conclusion ω-3PUFA can inhibit DEX resistant MM cell proliferation,arrest cell cycle and induce cell apoptosis,and has a synergistic anti-resistant effect in combination with DEX,may serve as a new,effective MM drugs.

Key words: ω-3 polyunsaturated fatty acids, Multiple myeloma, Dexamethasone, Drug resistance