RNAi Screening-based Identification of USP10 as a Novel Regulator of Paraptosis

Sci Rep. 2019 Mar 20;9(1):4909. doi: 10.1038/s41598-019-40982-z.

Abstract

Accumulating reports demonstrate that apoptosis does not explain all the effects of cancer therapy due to the innate and acquired apoptotic resistance of malignant cancer cells. Recently, paraptosis, a type of programmed cell death accompanied by dilation of mitochondria and/or the endoplasmic reticulum (ER), has garnered interest in cancer research as an alternative way to kill apoptosis-resistant cancers. We describe here the adaptation and validation of a high-content cell-based assay to screen and identify novel paraptotic regulators employing the malignant breast cancer cells undergoing curcumin-induced paraptosis. We used YFP-Mito cells, which express fluorescence selectively in mitochondria, to select paraptosis-related genes whose corresponding siRNAs appeared to modulate mitochondrial dilation, a morphological feature of paraptosis. From the selected 38 candidate genes, we chose ubiquitin specific peptidase 10 (USP10), a ubiquitin specific protease, as a strongly active candidate that warranted further evaluation of its involvement in paraptosis. We found that both siRNA-mediated knockdown of USP10 and treatment with the USP10 inhibitor, spautin-1, effectively attenuated curcumin-induced paraptosis. This systematic assay, in which a siRNA library is screened for the ability to ameliorate paraptotic changes in mitochondria, may enable researchers to identify potent regulators of paraptosis and new candidate genes/drugs to combat malignant breast cancer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antineoplastic Agents / pharmacology*
  • Benzylamines / pharmacology
  • Breast Neoplasms / drug therapy
  • Breast Neoplasms / enzymology
  • Breast Neoplasms / genetics
  • Breast Neoplasms / pathology
  • Cell Death / drug effects
  • Cell Death / genetics*
  • Cell Line, Tumor
  • Curcumin / pharmacology*
  • Endoplasmic Reticulum / drug effects*
  • Endoplasmic Reticulum / enzymology
  • Endoplasmic Reticulum / genetics
  • Female
  • Gene Library
  • High-Throughput Screening Assays
  • Humans
  • Membrane Potential, Mitochondrial / drug effects
  • Mitochondria / drug effects*
  • Mitochondria / enzymology
  • Mitochondria / genetics
  • Quinazolines / pharmacology
  • RNA Interference
  • RNA, Small Interfering / genetics
  • RNA, Small Interfering / metabolism
  • Ubiquitin Thiolesterase / antagonists & inhibitors
  • Ubiquitin Thiolesterase / genetics*
  • Ubiquitin Thiolesterase / metabolism

Substances

  • Antineoplastic Agents
  • Benzylamines
  • Quinazolines
  • RNA, Small Interfering
  • USP10 protein, human
  • spautin-1
  • Ubiquitin Thiolesterase
  • Curcumin