Use of the Differential Staining Cytotoxicity Assay to Predict Chemosensitivity

The differential staining cytotoxicity (DiSC) assay is one of the total cell-kill assays that can be used for drug resistance testing. Numerous publications have demonstrated the clinical value of chemosensitivity testing with that assay (and similar ones). The DiSC assay is successful in the majority of malignant samples of which the cells can be brought in suspension (not necessarily as single-cell suspension). Although the assay is laborious and requires skilled technicians, it requires few cells, can be used for proliferating and nonproliferating cell populations, and can discriminate between malignant and contaminating nonmalignant cells. The latter is a major advantage of the DiSC assay. This chapter describes the practical aspects of this assay, several topics that need to be taken into account, and potential pitfalls. As such, it is not an extensive review of studies in which the DiSC assay was used.