Comparison of the kinetics of 99Tcm-MIBI in tumor cells with or without MDR and the changes after MDR reversing agents / 中华核医学杂志

ABSTRACT

Objective Overexpression of multidrug resistance(MDR)is one of the mechanisms that will lead to chemotherapy failure.Of the MDR pathways in tumor cells,P-glycoprotein (P-gp) encoded by MDR genes is one of the key points.99Tcm-methoxyisobutylisonitrile(MIBI) is an imaging agent that can detect overexpression of MDR in tumor cells.The aim of this study was to observe the relationship between 99Tcm.MIBI uptake kinetics and P-gp levels in tumor cells,with or without MDR reversing agents.Methods A totle of 2×106 cells of human myelogeneous leukemia cell line K562 and its resistant subline(K562/D) were incubated with 8 MBq 99Tcm-MIBI respectively.99Tcm-MIBl accumulation and emux at various time inter-vats and the uptake difference with the presence of different cyclosporin A(O.1-O.4 ug/ml)were also ob-served.Comparison of different cell lines or without and with cyclosporin A were performed with the t-test, and the daa of different groups were compared by q-test.Results 99Tcm-MIBI uptake in K562 and K562/D cell line were 1.559±0.529 and 0.107±0.036,99Tcm-MIBI uptake in k562 was flitleon times higher than k562/D.As compared with K562 cell line with no expression of P-gp,significantly increased the 99Tcm-MIBI uptake of K562/D to 106%,148% and 163%after treated with cyclosporin A(0.1,0.2.0.4ug/ml)was ob-served(t=4.35,4.83,5.88,P<0.05).Conclusiom 99Tcm-MIBI uptake can reflect the P-gP level and multidrug-resistance inhibitor may impact 99Tcm-MIBI uptake in P-gP overexpressing cells.