A High-Content Assay Enables the Automated Screening and Identification of Small Molecules with Specific ALDH1A1-Inhibitory Activity

• Published in: PloS one Vol. 12; no. 1; p. e0170937
• Main Authors: Yasgar, Adam, Titus, Steven A, Wang, Yuhong, Danchik, Carina, Yang, Shyh-Ming, Vasiliou, Vasilis, Jadhav, Ajit, Maloney, David J, Simeonov, Anton, Martinez, Natalia J
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 27.01.2017; Public Library of Science (PLoS)
• Subjects: Alcohol; Aldehyde dehydrogenase; Aldehyde Dehydrogenase - antagonists & inhibitors; Aldehyde Dehydrogenase - biosynthesis; Aldehydes; Aldehydes - metabolism; Assaying; Automation; Biological Assay; Biology and Life Sciences; Cancer; Cell Line, Tumor; Cellular structure; Chemistry; Cocaine; Dehydrogenases; Dopamine; Drug dosages; Engineering and Technology; Environmental health; Enzyme Inhibitors - chemical synthesis; Enzyme Inhibitors - chemistry; Enzyme Inhibitors - pharmacology; Gene expression; Gene Expression Regulation, Enzymologic - drug effects; High-throughput screening; High-throughput screening (Biochemical assaying); Humans; Identification and classification; Inhibitors; Medical screening; Metabolism; Miniaturization; Molecular structure; Molecules; Neoplastic Stem Cells - drug effects; Oxidation; Oxidation-Reduction; Pharmaceutical sciences; Physical Sciences; Physiology; Proteins; Research and Analysis Methods; Screening; Small Molecule Libraries - chemical synthesis; Small Molecule Libraries - chemistry; Small Molecule Libraries - pharmacology; Stem cells; Structural analysis; Structure-Activity Relationship
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0170937

Aldehyde dehydrogenase enzymes (ALDHs) have a broad spectrum of biological activities through the oxidation of both endogenous and exogenous aldehydes. Increased expression of ALDH1A1 has been identified in a wide-range of human cancer stem cells and is associated with cancer relapse and poor prognosis, raising the potential of ALDH1A1 as a therapeutic target. To facilitate quantitative high-throughput screening (qHTS) campaigns for the discovery, characterization and structure-activity-relationship (SAR) studies of small molecule ALDH1A1 inhibitors with cellular activity, we show herein the miniaturization to 1536-well format and automation of a high-content cell-based ALDEFLUOR assay. We demonstrate the utility of this assay by generating dose-response curves on a comprehensive set of prior art inhibitors as well as hundreds of ALDH1A1 inhibitors synthesized in house. Finally, we established a screening paradigm using a pair of cell lines with low and high ALDH1A1 expression, respectively, to uncover novel cell-active ALDH1A1-specific inhibitors from a collection of over 1,000 small molecules.