Classification of estrogenic compounds by coupling high content analysis and machine learning algorithms.

Journal: PLoS computational biology
PMID:

Abstract

Environmental toxicants affect human health in various ways. Of the thousands of chemicals present in the environment, those with adverse effects on the endocrine system are referred to as endocrine-disrupting chemicals (EDCs). Here, we focused on a subclass of EDCs that impacts the estrogen receptor (ER), a pivotal transcriptional regulator in health and disease. Estrogenic activity of compounds can be measured by many in vitro or cell-based high throughput assays that record various endpoints from large pools of cells, and increasingly at the single-cell level. To simultaneously capture multiple mechanistic ER endpoints in individual cells that are affected by EDCs, we previously developed a sensitive high throughput/high content imaging assay that is based upon a stable cell line harboring a visible multicopy ER responsive transcription unit and expressing a green fluorescent protein (GFP) fusion of ER. High content analysis generates voluminous multiplex data comprised of minable features that describe numerous mechanistic endpoints. In this study, we present a machine learning pipeline for rapid, accurate, and sensitive assessment of the endocrine-disrupting potential of benchmark chemicals based on data generated from high content analysis. The multidimensional imaging data was used to train a classification model to ultimately predict the impact of unknown compounds on the ER, either as agonists or antagonists. To this end, both linear logistic regression and nonlinear Random Forest classifiers were benchmarked and evaluated for predicting the estrogenic activity of unknown compounds. Furthermore, through feature selection, data visualization, and model discrimination, the most informative features were identified for the classification of ER agonists/antagonists. The results of this data-driven study showed that highly accurate and generalized classification models with a minimum number of features can be constructed without loss of generality, where these machine learning models serve as a means for rapid mechanistic/phenotypic evaluation of the estrogenic potential of many chemicals.

Authors

  • Rajib Mukherjee
    Texas A&M Energy Institute, Texas A&M University, College Station, TX, United States of America.
  • Burcu Beykal
    Texas A&M Energy Institute, Texas A&M University, College Station, TX, United States of America.
  • Adam T Szafran
    Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, United States of America.
  • Melis Onel
    † Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, Texas 77843, United States.
  • Fabio Stossi
    Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, United States of America.
  • Maureen G Mancini
    Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, United States of America.
  • Dillon Lloyd
    Bioinformatics Research Center, Center for Human Health and the Environment, Department of Statistics, North Carolina State University, Raleigh, NC, United States of America.
  • Fred A Wright
    Bioinformatics Research Center, Center for Human Health and the Environment, Department of Statistics, North Carolina State University, Raleigh, NC, United States of America.
  • Lan Zhou
    CAS Key Laboratory of Tropical Plant Resources and Sustainable Use, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Kunming 650223, China.
  • Michael A Mancini
    Molecular and Cellular Biology, Baylor College of Medicine, Houston, TX, United States of America.
  • Efstratios N Pistikopoulos
    † Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, Texas 77843, United States.