Discovery of Small Molecules That Induce Lysosomal Cell Death in Cancer Cell Lines Using an Image-Based Screening Platform

Research output: Contribution to journalArticle

Abstract

The lysosomal cell death (LCD) pathway is a caspase 3-independent cell death pathway that has been suggested as a possible target for cancer therapy, making the development of sensitive and specific high-throughput (HT) assays to identify LCD inducers highly desirable. In this study, we report a two-step HT screening platform to reliably identify such molecules. First, using a robust HT primary screen based on propidium iodide uptake,we identified compounds that kill through nonapoptotic pathways. A phenotypic image-based assay using a galectin-3 (Gal-3) reporterwas then used to further classify hits based on lysosomal permeabilization, a hallmark of LCD. The identification of permeabilized lysosomes in our image-based assay is not affected by changes in the lysosomal pH, thus resolving an important limitation in currently usedmethods.We have validated our platform in a screen by identifying 24 LCD inducers, some previously known to induce LCD. Although most LCD inducers were cationic amphiphilic drugs (CADs), we have also identified a non-CAD LCD inducer, which is of great interest in the field. Our data also gave new insights into the biology of LCD, suggesting that lysosomal accumulation and acid sphingomyelinase inhibition are not sufficient or necessary for the induction of LCD. Overall, our results demonstrate a robust HT platform to identify novel LCD inducers that will also be very useful for gaining deeper insights into the molecular mechanism of LCD induction.

Details

Authors
  • Romina J. Pagliero
  • Diego S. D'Astolfo
  • Daphne Lelieveld
  • Riyona D. Pratiwi
  • Sonja Aits
  • Marja Jaattela
  • Nathaniel I. Martin
  • Judith Klumperman
  • David A. Egan
External organisations
  • University Medical Center Utrecht
  • Hubrecht Institute
  • Danish Cancer Society Research Center
  • Utrecht University
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Basic Medicine

Keywords

  • galectin-3 reporter, high throughput screening, LMP phenotypic assay, lysosomal cell dead
Original languageEnglish
Pages (from-to)489-510
JournalAssay and Drug Development Technologies
Volume14
Issue number8
Publication statusPublished - 2016 Oct 1
Publication categoryResearch
Peer-reviewedYes
Externally publishedYes