Translation of novel anti-cancer cytotoxicity biomarkers detected with high content analysis from an in vitro predictive model to an in vivo cell model.

Toxicology in vitro : an international journal published in association with BIBRA 2010 Jul 27; In press

Lieggi N NT, Edvardsson A, O'Brien P PJ

Veterinary Science Centre,University College Dublin, Belfield, Dublin 4, Ireland; Advanced Diagnostics Laboratory, Unit 0.13, Nova UCD, Belfield Innovation Park, University College Dublin, Belfield, Dublin 4, Ireland.

Using high content analysis (HCA), we assessed whether cytotoxicity biomarkers translate from in vitro to in vivo models using four anti-cancer drugs (arabinoside C, arsenic trioxide, doxorubicin, and mitoxantrone) and staining live cells with Hoechst 33342 for DNA (nuclear area, nuclear intensity and cell number), Fluo-4 for ionised calcium, TMRM for mitochondrial membrane potential and TOTO-3 for plasma membrane permeability. Human HepG2 hepatocytes and Jurkat T-lymphocytes were treated with 10-fold increasing concentrations of drug for 24 and 72h. We demonstrate that HCA can be carried out on suspension cells and that this in vivo model was at least as sensitive as the in vitro model. In addition, we show that the concentration of DOX in the nucleus and its anti-cancer mechanism of action can be assessed due to its intrinsic fluorescence and its DNA intercalation in competition with the Hoechst dye. We conclude cytotoxicity biomarkers translate from the in vitro, predictive, hepatocyte model to the in vivo lymphocyte model. Thus, HCA cytotoxicity biomarkers may not only be predictive of human toxicity potential but may be translatable for detection and monitoring of subclinical toxicity.

Keywords: biomarker