Evaluating the cytotoxic effects of novel quinone compounds

Abstract

Background/aim: Quinone-containing compounds can induce cell death in cancer cells and are, therefore, promising lead compounds for the development of novel anti-cancer drugs.

Materials and methods: In the present study, we evaluated the cytotoxic effects of fifteen novel synthetic quinone-containing compounds in cell cultures in an attempt to establish structure/activity relationships for these compounds. The compounds were clustered into four groups (1, 2, 3, 4) based on common structural features. In vitro cell cultures were treated for 24 h with the compounds, after which cell viability was assessed by flow cytometry. The APOPercentage™ assay, the Terminal deoxynucleotidyl transferase mediated dUTP Nick End Labeling (TUNEL) assay and the caspase-3 assay was used to investigate the activation of apoptosis in the cells.

Results: Compounds from groups 2 and 4 were highly toxic to the cells. The compounds induced apoptosis in some human cancer cell cultures and exhibited low toxicity towards the non-cancerous cell line, KMST-6. The induction of apoptosis in CHO cells was associated with the activation of caspase-3 cleavage, DNA fragmentation and the reactive oxygen species (ROS) generation.

Conclusion: The present study demonstrates that five of the quinone-containing compounds induced apoptosis in human cancer cells and are therefore promising lead compounds for the development of novel anticancer drugs.

Keywords: Cancer; apoptosis; quinone; structure/activity relationships.