DIFFERENTIAL NEUTRAL RED UPTAKE AS A POTENTIAL MARKER OF CANCER STATE

Distinctive uptake of neutral red (NR) has been previously reported to be characteristic of mitotic cancer cells. In a related study, we hav e shown differential NR accumulations in acidification-and-recovery be tween oral KB carcinoma and Chang liver cells. The present flow cytome tric study demonstrates the presence of differential NR uptake between the whole cell populations of non-tumourigenic human Chang liver cell s and four other established human carcinoma cell lines viz. lung (A42 7), colon (HCT 116), skin (A431) and human KB oral carcinoma. This was corroborated by image analysis of NR uptake in single KB and Chang ce lls with confocal laser scanning microscopy. Detection of cancer cells via pH, modulated NR uptake, suggests that the NR index of 'viability ' may also serve as a mechanism-based cancer cell discriminant.