Demethylation Of PTEN And P16 Of Osteosarcoma Suppressor Gene By Curcumin Combined With 5-Aza-CdR

Objective:To investigate whether curcumin can enhance the demethylation of 5-Aza-CdR on osteosarcoma tumor suppressor gene P16 and PTEN.Methods:(1)Curcumin with different concentrations and 5-Aza-CdR were used alone or in combination for osteosarcoma cells;(2)Inverted phase contrast microscope observe cell morphology;(3)cell growth inhibition rate was detected by CCK-8 method;(4)The methylation status of PTEN and P16 gene promoters in osteosarcoma cells before and after intervention was detected by methylation-specific PCR(MSP).(5)Apoptosis rate and apoptosis-related gene P16,PTEN were detected by flow cytometry and RT-PCR.(6)The expression of P16 and PTEN protein levels was detected by western blot.Results:(1)Curcumin inhibited the growth of osteosarcoma cells in a time-and concentration-dependent manner.(2)The results of MSP indicated that curcumin and 5-Aza-CdR had certain demethylation effects when used alone or in combination.Demethylation was significantly enhanced when they combined.(3)The results of RT-PCR and western blot showed that the expression of P16 and PTEN increased significantly when curcumin was combined with 5-AzaCdR(P<0.05).Conclusion:(1)Both curcumin and 5-Aza-CdR can inhibit the proliferation and induce apoptosis of human osteosarcoma Saos-2 cells;(2)Curcumin and 5-Aza-CdR can enhance the demethylation level of human osteosarcoma tumor suppressor gene P16 and PTEN;(3)Curcumin combined with 5-Aza-CdR treatment of human osteosarcoma Saos-2 cells can enhance the demethylation level of human osteosarcoma tumor suppressor gene P16 and PTEN,which is more effective than the single effect.