CUL4high Lung Adenocarcinomas Are Dependent on the CUL4-p21 Ubiquitin Signaling for Proliferation and Survival. Academic Article uri icon

Overview

abstract

  • Cullin (CUL) 4A and 4B ubiquitin ligases are often highly accumulated in human malignant neoplasms and are believed to possess oncogenic properties. However, the underlying mechanisms by which CUL4A and CUL4B promote pulmonary tumorigenesis remain largely elusive. This study reports that CUL4A and CUL4B are highly expressed in patients with non-small cell lung cancer (NSCLC), and their high expression is associated with disease progression, chemotherapy resistance, and poor survival in adenocarcinomas. Depletion of CUL4A (CUL4Ak/d) or CUL4B (CUL4Bk/d) leads to cell cycle arrest at G1 and loss of proliferation and viability of NSCLC cells in culture and in a lung cancer xenograft model, suggesting that CUL4A and 4B are oncoproteins required for tumor maintenance of certain NSCLCs. Mechanistically, increased accumulation of the cell cycle-dependent kinase inhibitor p21/Cip1/WAF1 was observed in lung cancer cells on CUL4 silencing. Knockdown of p21 rescued the G1 arrest of CUL4Ak/d or CUL4Bk/d NSCLC cells, and allowed proliferation to resume. These findings reveal that p21 is the primary downstream effector of lung adenocarcinoma dependence on CUL4, highlight the notion that not all substrates respond equally to abrogation of the CUL4 ubiquitin ligase in NSCLCs, and imply that CUL4Ahigh/CUL4Bhigh may serve as a prognostic marker and therapeutic target for patients with NSCLC.

publication date

  • June 11, 2021

Research

keywords

  • Adenocarcinoma of Lung
  • Cullin Proteins
  • Cyclin-Dependent Kinase Inhibitor p21
  • Lung Neoplasms

Identity

PubMed Central ID

  • PMC8420861

Scopus Document Identifier

  • 85113760246

Digital Object Identifier (DOI)

  • 10.1016/j.ajpath.2021.05.018

PubMed ID

  • 34119472

Additional Document Info

volume

  • 191

issue

  • 9