3D CRISPR screen in prostate cancer cells reveals PARP inhibitor sensitization through TBL1XR1-SMC3 interaction

Abstract

Poly(ADP-ribose) (PAR) polymerase inhibitors (PARPi) either have been approved or being tested in the clinic for the treatment of a variety of cancers with homologous recombination deficiency (HRD). However, cancer cells can develop resistance to PARPi drugs through various mechanisms, and new biomarkers and combination therapeutic strategies need to be developed to support personalized treatment. In this study, a genome-wide CRISPR screen was performed in a prostate cancer cell line with 3D culture condition which identified novel signals involved in DNA repair pathways. One of these genes, TBL1XR1, regulates sensitivity to PARPi in prostate cancer cells. Mechanistically, we show that TBL1XR1 interacts with and stabilizes SMC3 on chromatin and promotes γH2AX spreading along the chromatin of the cells under DNA replication stress. TBL1XR1-SMC3 double knockdown (knockout) cells have comparable sensitivity to PARPi compared to SMC3 knockdown or TBL1XR1 knockout cells, and more sensitivity than WT cells. Our findings provide new insights into mechanisms underlying response to PARPi or platin compounds in the treatment of malignancies.

Document Details

Document Type
Pub Defense Publication
Publication Date
Nov 29, 2022
Source ID
10.3389/fonc.2022.999302

Entities

People

  • Adeyemi A. Adeosun
  • August John
  • Huan Zhang
  • Huanyao Gao
  • Jia Yu
  • Liewei Wang
  • Lixuan Wei
  • Minhong Huang
  • Richard M. Weinshilboum
  • Yayun Gu

Organizations

  • National Institutes of Health
  • United States Department of Defense

Tags

Fields of Study

  • Biology
  • Medicine

Readers

  • Molecular Biology and Genetics
  • Oncology
  • Oncology (Cancer Research).

Technology Areas

  • Biotechnology