HMGB1 translocation is involved in the transformation of autophagy complexes and promotes chemoresistance in leukaemia

Int J Oncol. 2015 Jul;47(1):161-70. doi: 10.3892/ijo.2015.2985. Epub 2015 May 4.

Abstract

Acute lymphoblastic leukaemia (ALL) is a common paediatric cancer and is among the most curable cancers. However, the acquisition of drug resistance is a significant obstacle to the achievement of favourable outcomes, and autophagy is regarded as a mechanism that underlies chemoresistance. In this study, RT-qPCR was used to measure the expression of HMGB1 and Beclin1 in bone marrow mononuclear cells. A CCK-8 test was conducted to assess cell viability. Western blot, immunofluorescence and transmission electron microscopic analyses were performed to evaluate the autophagy levels. Immunoprecipitation analysis was performed to detect protein-protein interactions in the autophagy complexes. We found that HMGB1 expression correlated with the clinical status of ALL. In vitro, anticancer agent-induced cytotoxic effects were associated with autophagy-related drug resistance, and these effects were ameliorated by FIP200 depletion or the application of autophagy inhibitors. Moreover, the Ulk1‑Atg13-FIP200 complex, which promotes HMGB1 trafficking, acted upstream of the HMGB1-Beclin1 and PI3KC3-Beclin1 complexes and played a critical role in autophagy. Targeting the transformation of autophagic complexes or HMGB1 translocation may suppress autophagy and consequently overcome chemoresistance in leukaemia.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apoptosis Regulatory Proteins / genetics
  • Autophagy
  • Beclin-1
  • Cell Line, Tumor
  • Drug Resistance, Neoplasm*
  • HMGB1 Protein / genetics*
  • HMGB1 Protein / metabolism*
  • Humans
  • Jurkat Cells
  • Membrane Proteins / genetics
  • Precursor B-Cell Lymphoblastic Leukemia-Lymphoma / genetics
  • Precursor B-Cell Lymphoblastic Leukemia-Lymphoma / metabolism
  • Precursor B-Cell Lymphoblastic Leukemia-Lymphoma / pathology*
  • Protein Transport

Substances

  • Apoptosis Regulatory Proteins
  • BECN1 protein, human
  • Beclin-1
  • HMGB1 Protein
  • HMGB1 protein, human
  • Membrane Proteins