ABSTRACT
@# Objective: To explore the resistance of CD133+ cells in HepG2 cell line to doxorubicin (DOX) and its mechanism. Methods: CD133+ cells were sorted by magnetic beads and CD133+ positive rate was detected by flow cytometry. MTT assay was used to detect the resistance to DOX-induced apoptosis of CD133+ cells. The expression of BCRP transporter mRNA was detected by RT-PCR. The expression of apoptosis-related proteins was detected by Western blotting. Immunofluorescence assay was used to detect the activation and transportation of P65 after DOX treatment. Results: Magnetic beads sorting could efficiently sort the CD133+ cells from HepG2 cells. MTT proliferation assay showed that CD133+ cells had stronger resistance to DOX than CD133- cells (P<0.05). Immunofluorescence showed that the activation rate and content of P65 in CD133+ cells were significantly higher than those in CD133- cells and HepG2 cells (P<0.05). The results of RT-PCR showed that the mRNA content of BCRP in CD133+ cells was significantly increased compared with CD133- cells and HepG2 cells (all P<0.05). Compared with HepG2 and CD133- groups, the expression of Bax and p53 in CD133+ cells was significantly decreased (P<0.05), while the expression of Bcl-2 and Survivin protein in CD133+ cells was significantly increased (P<0.05 or P<0.01). Conclusion: The molecular mechanism of high DOX-resistance of the CD133+ cell subsets in HepG2 cells is the high expression of the survival-related proteins NF-κB, Bcl-2, Survivin and the drug-resistance transporter BCRP, and low expression of apoptosis-promoting proteins p53 and Bax.
ABSTRACT
Aim The release process of an anticancer agent, DOX_HAP in rabbit liver was observed.Methods DOX and DOX_HAP were separately injectoed into rabbit livers under the guide of B type ultrasound. Dox concentrations in plasma and liver tissue of the rabbits in both groups were measured by fluorescent stectrophotometer and compared. Results The concentration of complex could existed in the liver tissue about 5 d(1 000 ng?g-1) when it was given in a dose of 2 mg?g-1. At the 10 min the concentration in plasma would be reduced about 1/2 as compared with that in the control group. Conclusions The DOX_ HAP complex not only could increase and insist in an effective concentration of DOX at the local injecting area of liver tissue, but also reduce its concerntration in the plasma. Therefore, it could decrease the toxicity and side_effect of DOX.