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Assays for Tumor Response to Radiation
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Clonogenic assays (plating assays): tumors are excised, reduced to
single cells, and grown in a test environment
- provide a direct measure of the surviving fraction of clonogenic cells.
- limitation: relationshipbetween clonogens (in test
environment) and stemcells (in situ) is uncertain.
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Culturing as organoids: tumors are excised, reduced to single cells, and
grown in 3D matrix
- Measurement of tumor stem cells
- Show potential to differentiate in all tumor subtype cells
- lack of environmental factors,… vascularisation
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In Situ assays (growth delay, tumor control): tumors left in place.
- measure response of effective and potential stemcells.
- limitation: no quantitation of stemcells; surviving fraction is
difficult to assess.