摘要
MDM2 was transfected to acute lymphoblastic leukemia (ALL) line EU-4 cell which lacks P53 expression and expresses very low levels of MDM2. The results showed that MDM2 up-regulated P65 expression in mRNA level and protein level. The effect of adriamycin (ADM) on MDM2-transfected EU-4 cell was detected by MTT assay. It was found that MDM2 transfection could increase drug resistance of EU-4 cells to ADM as compared with parent cells. Since the expression of E-selectin is P65 dependent, E-selectin promoter-CAT construct and P65 and MDM2 expression plasmids were co-transfected to EU-4 cells, revealing that MDM2 increased P65-mediated transactivation of E-selectin promoter. In the absence of P65, MDM2 had no effect on the transactivation of E-selectin. Moreover, MDM2 antisense couldn't change the transactivation of E-selectin. It was concluded that MDM2 could up-regulate transcriptionally P65 expression; MDM2 increased drug resistance of leukemia cells to ADM; MDM2 elevated NF-kappaB activity in a P53-independent manner.
MDM2 was transfected to acute lymphoblastic leukemia (ALL) line EU-4 cell which lacks P53 expression and expresses very low levels of MDM2. The results showed that MDM2 up-regulated P65 expression in mRNA level and protein level. The effect of adriamycin (ADM) on MDM2-transfected EU-4 cell was detected by MTT assay. It was found that MDM2 transfection could increase drug resistance of EU-4 cells to ADM as compared with parent cells. Since the expression of E-selectin is P65 dependent, E-selectin promoter-CAT construct and P65 and MDM2 expression plasmids were co-transfected to EU-4 cells, revealing that MDM2 increased P65-mediated transactivation of E-selectin promoter. In the absence of P65, MDM2 had no effect on the transactivation of E-selectin. Moreover, MDM2 antisense couldn't change the transactivation of E-selectin. It was concluded that MDM2 could up-regulate transcriptionally P65 expression; MDM2 increased drug resistance of leukemia cells to ADM; MDM2 elevated NF-kappaB activity in a P53-independent manner.
基金
This project was supported by a grant from National Natu-ral Sciences Foundation of China ( No.3 9970 778)
