Epithelial cells were isolated and cultured from a number of human mammary specimens of both cancerous and noncancerous origin. Doxorubicin (Dx) sensitivity was measured at second passage with the use of a highly efficient clonogenic assay. For 23 different tumor specimens derived from patients without previous chemotherapy, the drug concentrations required to kill 50% of the cells varied approximately 35-fold. In contrast, for 11 tumor specimens from patients who relapsed after regimens contanining Dx, the drug concentration for 50% survival varied only fivefold and the dose-response curves for these specimens clustered at the more resistant end of the spectrum. A wide range of sensitivities was also observed among 13 noncancerous mammary specimens; however, tumor tissue and noncancerous tissue from the same donor were similar. When cultures were subjected to drug incubation periods of 1 and 4 hours, dose-response curves were superimposable when plotted as a function of drug concentration multiplied by time.
|Original language||English (US)|
|Number of pages||7|
|Journal||Journal of the National Cancer Institute|
|State||Published - Jul 4 1985|
ASJC Scopus subject areas
- Cancer Research