[Chemosensitivity test on superficial urinary bladder cancer using the dye exclusion assay--model of intravesical chemotherapy]

A chemosensitivity test was carried out on superficial bladder cancers using the trypan blue dye exclusion assay for the purpose of screening chemosensitive drugs for intravesical chemotherapy. Transplantable murine bladder tumor cells (MBT-2) were incubated, in vitro, in the presence of adriamycin (4, 40, 400, 1000 micrograms/ml) as well as verapamil (3, 30, 100, 500 micrograms/ml) at 5% CO2, 37 degrees C for two hours. After cellular viabilities were calculated, MBT-2 cells were inoculated into the hind limbs of mice. The cellular viability was correlated well with the ratio of tumor appearance, tumor growth inhibition and prolongation of survival, and was dose dependent in the adriamycin treated groups. On the other hand, a reduction of cellular viability, tumor growth inhibition and prolongation of survival were seen in the high dose verapamil (100, 500 micrograms/ml) treated groups. Human superficial bladder cancer cells were incubated in the presence of adriamycin, 4'-0-tetrahydropyranyladriamycin, mitomycin C and pepleomycin (1000 micrograms/ml) and/or verapamil (500 micrograms/ml). The reduction rates of cellular viability markedly varied with the kind of anticancer drugs. A reduction of cellular viability of human tumor cells as well as MBT-2 cells was seen in the verapamil treated groups. This rapid and handy assay seems to be useful for the purpose of screening chemosensitive drugs for intravesical chemotherapy.