Wideł M, Dobrut M, Maka B, Lubecka B, Pluciennik A
Laboratory of Radiobiology, Maria Skłodowska-Curie Memorial Institute, Gliwice, Poland.
Neoplasma. 1997;44(2):109-16.
Cytokinesis-block micronucleus assay (CB-MNA) was applied for comparison of radiation sensitivity of 25 human malignant melanomas in primary culture. Cells obtained from tumor specimens were irradiated (0-4.Gy) on dishes, incubated with cytochalasin B (2 micrograms/ml) to block cytokinesis, stained in situ and micronuclei (MN) scored in binucleate cells (BNC). Proportions of BNC in nonirradiated controls after fixed time of incubation (96 h) ranged from 2.3 to 38% indicating great differences (C.V. = 74%) in proliferative activity among tumors evaluated. No correlation was observed between proliferative activity and susceptibility of cells to induction of MN by radiation. The great inter-tumor heterogeneity was observed in respect of radiation sensitivity expressed either as normalized (Net) frequency (Fq) of BNC with MN or as number of MN per BNC. Both endpoints differed widely at 2 Gy and 4 Gy as well (Net FqBNC with MN = 0.28-25.4% or 1.5-45% and MN/BNC = 0.004-0.309 or 0.013-0.593 respectively at 2 Gy and 4 Gy) with coefficients of variation ranging from 44 to 57%. Extreme difference in MN frequency was also observed between one primary tumor and its metastasis indicating intra-tumor heterogeneity. Our results suggest that CB-MNA may contribute some clinically useful information for discriminating tumors that will eventually respond to radiotherapy and those that will probably not. However, studies aimed at comparison of MN induction in vitro with clinical radioresponsiveness of malignant melanomas are urgently required.
采用胞质分裂阻滞微核试验（CB-MNA）比较25种原代培养的人恶性黑色素瘤的辐射敏感性。从肿瘤标本中获取的细胞在培养皿上接受照射（0 - 4 Gy），用细胞松弛素B（2微克/毫升）孵育以阻滞胞质分裂，原位染色并对双核细胞（BNC）中的微核（MN）进行计数。在固定孵育时间（96小时）后，未照射对照组中BNC的比例在2.3%至38%之间，表明所评估的肿瘤之间增殖活性存在很大差异（变异系数=74%）。未观察到增殖活性与细胞对辐射诱导MN的易感性之间存在相关性。在以含MN的BNC的标准化（净）频率（Fq）或每个BNC的MN数量表示的辐射敏感性方面，观察到肿瘤间存在很大的异质性。在2 Gy和4 Gy时，两个终点也有很大差异（2 Gy和4 Gy时，含MN的净FqBNC分别为0.28% - 25.4%或1.5% - 45%，MN/BNC分别为0.004 - 0.309或0.013 - 0.593），变异系数在44%至57%之间。在一个原发性肿瘤与其转移灶之间也观察到MN频率的极端差异，表明肿瘤内存在异质性。我们的结果表明，CB-MNA可能为区分最终对放疗有反应的肿瘤和可能无反应的肿瘤提供一些临床有用信息。然而，迫切需要进行旨在比较体外MN诱导与恶性黑色素瘤临床放射反应性的研究。
