Affordable Access

deepdyve-link
Publisher Website

Elimination of dormant, autophagic ovarian cancer cells and xenografts through enhanced sensitivity to anaplastic lymphoma kinase inhibition.

Authors
  • Blessing, Alicia M1
  • Santiago-O'Farrill, Janice M1
  • Mao, Weiqun1
  • Pang, Lan1
  • Ning, Jing2
  • Pak, Daewoo2
  • Bollu, Lakshmi Reddy1
  • Rask, Philip1
  • Iles, LaKesla1
  • Yang, Hailing1
  • Tran, Samantha1
  • Elmir, Ezzeddine1
  • Bartholomeusz, Geoffrey1
  • Langley, Robert1
  • Lu, Zhen1
  • Bast, Robert C Jr1
  • 1 Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.
  • 2 Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.
Type
Published Article
Journal
Cancer
Publisher
Wiley (John Wiley & Sons)
Publication Date
Jun 02, 2020
Identifiers
DOI: 10.1002/cncr.32985
PMID: 32484926
Source
Medline
Keywords
Language
English
License
Unknown

Abstract

Poor outcomes for patients with ovarian cancer relate to dormant, drug-resistant cancer cells that survive after primary surgery and chemotherapy. Ovarian cancer (OvCa) cells persist in poorly vascularized scars on the peritoneal surface and depend on autophagy to survive nutrient deprivation. The authors have sought drugs that target autophagic cancer cells selectively to eliminate residual disease. By using unbiased small-interfering RNA (siRNA) screens, the authors observed that knockdown of anaplastic lymphoma kinase (ALK) reduced the survival of autophagic OvCa cells. Small-molecule ALK inhibitors were evaluated for their selective toxicity against autophagic OvCa cell lines and xenografts. Autophagy was induced by reexpression of GTP-binding protein Di-Ras3 (DIRAS3) or serum starvation and was evaluated with Western blot analysis, fluorescence imaging, and transmission electron microscopy. Signaling pathways required for crizotinib-induced apoptosis of autophagic cells were explored with flow cytometric analysis, Western blot analysis, short-hairpin RNA knockdown of autophagic proteins, and small-molecule inhibitors of STAT3 and BCL-2. Induction of autophagy by reexpression of DIRAS3 or serum starvation in multiple OvCa cell lines significantly reduced the 50% inhibitory concentration of crizotinib and other ALK inhibitors. In 2 human OvCa xenograft models, the DIRAS3-expressing tumors treated with crizotinib had significantly decreased tumor burden and long-term survival in 67% to 79% of mice. Crizotinib treatment of autophagic cancer cells further enhanced autophagy and induced autophagy-mediated apoptosis by decreasing phosphorylated STAT3 and BCL-2 signaling. Crizotinib may eliminate dormant, autophagic, drug-resistant OvCa cells that remain after conventional cytoreductive surgery and combination chemotherapy. A clinical trial of ALK inhibitors as maintenance therapy after second-look operations should be seriously considered. © 2020 American Cancer Society.

Report this publication

Statistics

Seen <100 times