Keap1 mutation renders lung adenocarcinomas dependent on Slc33a1

Nat Cancer. 2020 Jun;1(6):589-602. doi: 10.1038/s43018-020-0071-1. Epub 2020 Jun 8.

Abstract

Approximately 20-30% of human lung adenocarcinomas (LUAD) harbor loss-of-function (LOF) mutations in Kelch-like ECH Associated-Protein 1 (KEAP1), which lead to hyperactivation of the nuclear factor, erythroid 2-like 2 (NRF2) antioxidant pathway and correlate with poor prognosis1-3. We previously showed that Keap1 mutation accelerates KRAS-driven LUAD and produces a marked dependency on glutaminolysis4. To extend the investigation of genetic dependencies in the context of Keap1 mutation, we performed a druggable genome CRISPR-Cas9 screen in Keap1-mutant cells. This analysis uncovered a profound Keap1 mutant-specific dependency on solute carrier family 33 member 1 (Slc33a1), an endomembrane-associated protein with roles in autophagy regulation5, as well as a series of functionally-related genes implicated in the unfolded protein response. Targeted genetic and biochemical experiments using mouse and human Keap1-mutant tumor lines, as well as preclinical genetically-engineered mouse models (GEMMs) of LUAD, validate Slc33a1 as a robust Keap1-mutant-specific dependency. Furthermore, unbiased genome-wide CRISPR screening identified additional genes related to Slc33a1 dependency. Overall, our study provides a strong rationale for stratification of patients harboring KEAP1-mutant or NRF2-hyperactivated tumors as likely responders to targeted SLC33A1 inhibition and underscores the value of integrating functional genetic approaches with GEMMs to identify and validate genotype-specific therapeutic targets.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adenocarcinoma of Lung* / genetics
  • Animals
  • Humans
  • Kelch-Like ECH-Associated Protein 1* / genetics
  • Lung Neoplasms* / genetics
  • Membrane Transport Proteins* / genetics
  • Mice
  • Mutation
  • NF-E2-Related Factor 2 / genetics

Substances

  • KEAP1 protein, human
  • Keap1 protein, mouse
  • Kelch-Like ECH-Associated Protein 1
  • Membrane Transport Proteins
  • NF-E2-Related Factor 2
  • SLC33A1 protein, human
  • Slc33a1 protein, mouse