BACKGROUNDTo evaluate the significance of flow cytometry (FCM) in the analysis of multi-drug resistance of doxorubicin.

METHODSThe level of doxorubicin or Rh-123 in S-180R and BGC-823/DOX, which were two cell lines with different drug resistance, was measured by FCM comparatively and continuously.

RESULTSThe total fluorescence profile peaks of S-180R, a high resistant cell line, were predominantly different from those of S-180, the parent cell line, by the FCM analysis. The subtle fluorescence profile differences between BGC-823/DOX (a low resistant cell line) and the parent cell line were quantitatively measured on the FCM map. The changes of each resistant cell fluorescence from the S 180R cells could be displayed by continuous tests, the more near the fluorescence level of each cell was, the more the fluorescence pike of whole cells centralized.

CONCLUSIONSFCM is a sensitive, accurate and quantitative test in the analysis of doxorubicin drug resistance.