Assessment of intrinsic radiosensitivity of human bladder cancer cell lines using colorimetric-MTT and micronucleus assays

✍ Scribed by Ryusuke Futatsuya; Hitomi Kimura; Masatoshi Maeda; Miki Shoji; Takashi Honda

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 497 KB
• Volume: 4
• Category: Article
• ISSN: 1065-7541
• DOI: 10.1002/(sici)1520-6823(1996)4:6<249::aid-roi1>3.0.co;2-y

✦ Synopsis

There are two groups of patients in local invasive bladder cancer, which are radiosensitive and radioresistant groups. It is useful to select radiosensitive patients before irradiation using an appropriate predictive assay because their prognosis after radiation therapy is better than in radioresistant group. We evaluated the intrinsic radiosensitivity of two established human bladder cancer cell lines, NBT-2 and T24, using colorimetric-MTT and micronucleus assays, and compared their results with standard clonogenic cell survival assays. We could get the same shape of survival curves using MTT assays as clonogenic assays for NBT-2 and T24 cells. However, the slopes of curves were more shallow and no significant difference on SF, values of two cell lines was observed using MTT assays. Using cytokinesis-blocked micronucleus assays, the difference of intrinsic radiosensitivity of two cell lines was clearly shown at very low dose range, from 0.25 to 2 Gy, which are daily fractional doses in clinical radiation therapy including the hyperfracdonation method. Therefore, we conclude that micronucleus assay is more useful for evaluating the response for daily fractional dose range than MTT assay. MTT assay may be fit for larger fractional doses or a single fraction regimen.