Predictive Capability of QSAR Models Based on the CompTox Zebrafish Embryo Assays: An Imbalanced Classification Problem

Molecules

Göran Klobučar¹  JayJ. Liu²  Mario Lovrić³  Roman Kern³  Olga Malev⁴  Bono Lučić⁴ 

[1] Department of Biology, Faculty of Science, University of Zagreb, Rooseveltov Trg 6, 10000 Zagreb, Croatia;Department of Chemical Engineering, Pukyong National University, Busan 608-739, Korea;Know-Center, Inffeldgasse 13, 8010 Graz, Austria;Ruđer Bošković Institute, P.O. Box 180, 10002 Zagreb, Croatia;

关键词: predictive QSAR;    toxicity;    ToxCast;    zebrafish embryo;    rdkit;    structural descriptors;   

DOI  :  10.3390/molecules26061617

来源: DOAJ

【 摘 要 】

The CompTox Chemistry Dashboard (ToxCast) contains one of the largest public databases on Zebrafish (Danio rerio) developmental toxicity. The data consists of 19 toxicological endpoints on unique 1018 compounds measured in relatively low concentration ranges. The endpoints are related to developmental effects occurring in dechorionated zebrafish embryos for 120 hours post fertilization and monitored via gross malformations and mortality. We report the predictive capability of 209 quantitative structure–activity relationship (QSAR) models developed by machine learning methods using penalization techniques and diverse model quality metrics to cope with the imbalanced endpoints. All these QSAR models were generated to test how the imbalanced classification (toxic or non-toxic) endpoints could be predicted regardless which of three algorithms is used: logistic regression, multi-layer perceptron, or random forests. Additionally, QSAR toxicity models are developed starting from sets of classical molecular descriptors, structural fingerprints and their combinations. Only 8 out of 209 models passed the 0.20 Matthew’s correlation coefficient value defined a priori as a threshold for acceptable model quality on the test sets. The best models were obtained for endpoints mortality (MORT), ActivityScore and JAW (deformation). The low predictability of the QSAR model developed from the zebrafish embryotoxicity data in the database is mainly due to a higher sensitivity of 19 measurements of endpoints carried out on dechorionated embryos at low concentrations.

【 授权许可】

Unknown