RESUMO
OBJECTIVE: To investigate the mechanism of receptors for retinoids inducing apoptosis of human melanoma cell line A375. METHODS: The effects of 3 kinds of retinoids (9-cis-RA, at-RA and 13-cis-RA), of TTNPB (RAR agonist) and of Methoprene acid (Ma, RXR agonist) on apoptosis of A375 cells were studied by detecting the expression of Bcl-2/Bax and by using. Annexin V/PI staining analysis, TUNEL detection and active Caspase-3 analysis. RESULTS: Retinoids and TTNPB could up-regulate the expression of Bax and down-regulate the expression of Bcl-2. The results of TUNEL and Annexin V/PI staining analysis showed that all of retinoids and TTNPB could induce apoptosis of A375 cells, compared with control group (P < 0.05); the effect of TTNPB was significantly greater than that of others (P < 0.05), but Ma was similar to the control (P > 0.05). Active Caspase-3 analysis showed that TTNPB and all of retinoids could up-regulate the expression of Caspase-3, and the effect of TTNPB was significantly greater than that of others (P < 0.05). CONCLUSION: Caspase-3 pathway is involved in the process for retinoids inducing apoptosis of A375 cells. The activation of RAR may have relation with retinoids inducing apoptosis of A375 cells, but may have no longer relation with RXR.
