Measuring cytotoxicity: a new perspective on LC50.

Abstract

BACKGROUND:

Cytotoxicity in cell culture is typically expressed as LC50 the concentration of a given agent which is lethal to 50% of the cells. This number is dependent on the incubation time with the agent. Previously, a two-term exponential model has been proposed to describe cell growth after a cytotoxic event: y(t) = k, * exp(-d(1)*t) + k2 * exp(d(2)*t). A dose-response relationship was observed between the parameter k2 in this formula and the concentration of the cytotoxic agent etoposide, in high-grade glioma cells was independent of incubation time.

MATERIALS AND METHODS:

In order to test if the model can be applied more generally, DAOY medulloblastoma cells treated with MS275, a histone deacetylase inhibitor, were used.

RESULTS:

The observed data fit the model well.

CONCLUSION:

The concentration at which k2 is reduced by 50% is called KC50. It provides a far better description of the cytotoxicity of an agent in a specific cell line than the traditional LC50.

• Authors: Ming Zhang, Dolly Aguilera, Chandra Das, Hernan Vasquez, Peter Zage, Vidya Gopalakrishnan, Johannes Wolff
• Journal: Anticancer research (Anticancer Res) 2007 Jan-Feb Vol. 27 Issue 1A Pg. 35-8 ISSN: 0250-7005 [Print] Greece
• PMID: 17352213 (Publication Type: Journal Article)

Chemical References

• Antineoplastic Agents
• Benzamides
• Pyridines
• entinostat

Topics

• Antineoplastic Agents (pharmacokinetics, pharmacology)
• Benzamides (pharmacokinetics, pharmacology)
• Cell Line, Tumor
• Child, Preschool
• Dose-Response Relationship, Drug
• Drug Screening Assays, Antitumor (methods)
• Humans
• Male
• Medulloblastoma (drug therapy, metabolism)
• Models, Biological
• Pyridines (pharmacokinetics, pharmacology)