RESUMO
AIM:To investigate the effects of gonadotropin-releasing hormone ( GnRH) analogue on the growth of breast cancer cell lines MCF-7 and MDA-MB-231 in vitro and to explore the related mechanisms with PI 3K/Akt or ERK/MAPK pathways .METHODS: The proliferation of human breast cancer cell lines MCF-7 and MDA-MB-231 treatment with triptorelin was detected by MTT assay and the distribution of the cell cycle was determined by flow cytometry .The phosphorylation of the ERK 1/2 and Akt was evaluated by Western blotting .RESULTS:Triptorelin inhibited the prolifera-tion of MCF-7 cells at concentration of 10-5 mol/L after treated for 192 h or at concentration of 10 -4 mol/L after treated for 168 h and 192 h.Triptorelin inhibited the proliferation of MDA-MB-231 cells at concentration of 10 -4 mol/L after treated for 192 h (P0.05).CONCLUSION:Inhibitory effect of GnRH analogue triptorelin on human breast cancer cells is not just the connection with the down-regulation of pituitary hormone , but also a direct in-hibitory effect.The role may not be involved in the activation of ERK /MAPK and PI3K/Akt signaling pathways .