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PubMed · 10606413

The comet assay in clinical practice.

P L Olive·R E Durand·S M Jackson·J C Le Riche·C Luo·R Ma·D B McLaren·C Aquino-Parsons·T A Thomson·T Trotter
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Abstract

The comet assay is a single-cell gel electrophoresis technique that measures DNA damage in individual cells. Since radiation produces 3-4 times more DNA damage in well-oxygenated cells compared with hypoxic cells, this assay can quantify the fraction of radiation-resistant hypoxic cells found in many solid tumours. This paper summarizes our results with 73 accessible metastatic tumours irradiated with palliative intent. Hypoxic fractions ranged from 0.0 to 0.67 with a mean of 0.15; 62% of these advanced tumours showed a hypoxic fraction > 0.05. Comparisons between two sequential aspirates in 33 tumours gave a slope of 0.92 (r2 = 0.88), suggesting that a single aspirate is generally representative of the tumour. A limitation, however, is that the hypoxic fraction could not be measured in clinical samples given a conventional dose of 2 Gy.

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AnimalsBiopsy, NeedleCell HypoxiaComet AssayDNA DamageElectrophoresisHumansMiceMice, Inbred C3HNeoplasmsJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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P L Olive, R E Durand, S M Jackson, J C Le Riche, C Luo, R Ma, D B McLaren, C Aquino-Parsons, T A Thomson, T Trotter. 1999. The comet assay in clinical practice.. https://doi.org/10.1080/028418699432527

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