[A new anticancer drug sensitivity test using the microplate culture and surviving tumor cell staining method]

We have developed a new anticancer drug sensitivity test using the short-term microplate culture and viable cell staining method, and the details of this method are reported. The tumor cells are cultured with the anticancer drugs for 2 days and 4 days. After culture, the microplate is centrifuged. The surviving tumor cells are fixed with ethanol and stained with crystal violet. After washing out the remaining crystal violet, 200 microliters of sodium lauryl sulfate is put into each microwell and the absorbance of each is measured. When we examined this method using leukemic cell lines, we found that the numbers of cells were in proportion to the absorbance, and that the surviving cells could be counted by the absorbance within the range of 0.4 to 1.7. On the assumption that the effective range is more than 60% of the cytotoxicity index (CI), tables of CI classified into drugs, concentrations and duration of culture for each leukemic cell line were made. With these tables, comparison of the anticancer drugs and subsequent selection of the effective ones became easier. This method is simple, rapid and convenient for handling a large volume of material. Its application to further clinical practice is therefore expected.