Related Experiment Video
Updated: Dec 7, 2025
Viability Assays for Cells in Culture
Published on: January 20, 2014
DRAQ7 as an Alternative to MTT Assay for Measuring Viability of Glioma Cells Treated With Polyphenols
Harcharan Kaur Rooprai1, Patrick Lawrence1,2, Sholeh Keshavarz1
1Department of Neurosurgery, King's College Hospital, London, U.K.
Background/Aim:
The tetrazolium-based MTT cytotoxicity assay is well established for screening putative anti-cancer agents. However, it has limitations including lack of reproducibility with glioma cells treated with polyphenols. The aim of this study was to evaluate whether a flow cytometric assay with the anthraquinone, DRAQ7, was a better alternative than the colorimetric MTT assay for measuring cell viability.
Materials And Methods:
Two glioma cell lines (IPSB-18, U373) and 1 pancreatic cancer cell line (AsPC-1) were treated with 4 polyphenols, namely red grape seed extract, red clover extract, anthocyanin-rich extract and curcumin. Cell viability was assessed using MTT assay and DRAQ7 staining.
Results:
Limitations of MTT assay included lack of sensitivity and interference with the structure and absorbance spectra of polyphenols. Also, DMSO was toxic to glioma cells. Microscopic observations of cells treated with polyphenols confirmed the range of IC50 values evaluated by DRAQ7, but not by the MTT assay.
Conclusion:
DRAQ7 is a better alternative than MTT for measuring viability of glioma cells treated with brightly coloured polyphenols.
Insights
The DRAQ7 flow cytometry assay is superior to the MTT assay for assessing glioma cell viability when treated with colorful polyphenols, overcoming MTT assay limitations.
Area of Science:
- Cancer research
- Cell biology
- Pharmacology
Background:
- The MTT assay is a standard method for screening anti-cancer drugs.
- MTT assay has reproducibility issues with glioma cells and polyphenols.
- Polyphenols can interfere with MTT assay measurements.
Purpose of the Study:
- To compare the efficacy of DRAQ7 flow cytometry assay versus MTT assay.
- To evaluate cell viability in glioma and pancreatic cancer cells treated with polyphenols.
- To determine a more reliable method for assessing cytotoxicity of polyphenols.
Main Methods:
- Utilized two glioma cell lines (IPSB-18, U373) and one pancreatic cancer cell line (AsPC-1).
- Treated cells with four polyphenols: red grape seed extract, red clover extract, anthocyanin-rich extract, and curcumin.
- Assessed cell viability using both MTT assay and DRAQ7 staining.
Main Results:
- MTT assay showed limited sensitivity and interference from polyphenol absorbance.
- DMSO, used in MTT assay, exhibited toxicity towards glioma cells.
- DRAQ7 assay results correlated with microscopic observations, unlike MTT assay, for IC50 values.
Conclusions:
- DRAQ7 staining is a more reliable method than MTT assay for assessing glioma cell viability.
- DRAQ7 overcomes limitations associated with MTT assays when using brightly colored polyphenols.
- This finding improves the accuracy of anti-cancer agent screening, particularly for polyphenol compounds.
