Zinc and p53 disrupt mitochondrial binding of HK2 by phosphorylating VDAC1

Exp Cell Res. 2019 Jan 1;374(1):249-258. doi: 10.1016/j.yexcr.2018.12.002. Epub 2018 Dec 4.

Abstract

Many cell death regulators physically or functionally interact with metabolic enzymes. These interactions provide insights into mechanisms of anticancer treatments from the perspective of tumor cell metabolism and apoptosis. Recent studies have shown that zinc and p53 not only induce tumor cell apoptosis, but also regulate tumor cell metabolism. However, the underlying mechanism is complex and remains unclear, making further research imperative to provide clues for future cancer treatments. In this study, we found that hexokinase 2 (HK2), which has dual metabolic and apoptotic functions, is downstream of zinc and p53 in both prostate cancer patient tissue and prostate cancer cell lines. Notably, the mitochondrial location of HK2 is crucial for its function. We demonstrate that zinc and p53 disrupt mitochondrial binding of HK2 in prostate cancer cells by phosphorylating VDAC1, which is mediated by protein kinase B (Akt) inhibition and glycogen synthase kinase 3β (GSK3β) activation. In addition, we found that zinc combined with p53 significantly inhibited tumor growth in a prostate cancer cell xenograft model. Therefore, interference of the mitochondrial localization of HK2 by zinc and p53 may provide a new treatment approach for cancer.

Keywords: Akt; GSK3β; HK2; VDAC; Zinc; p53.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis
  • Cell Line, Tumor
  • Glycogen Synthase Kinase 3 beta / metabolism
  • Hexokinase / metabolism*
  • Humans
  • Male
  • Membrane Potential, Mitochondrial
  • Mice, Inbred BALB C
  • Mice, Nude
  • Mitochondria / metabolism*
  • Phosphorylation
  • Prostatic Neoplasms / metabolism
  • Prostatic Neoplasms / pathology
  • Protein Binding
  • Proto-Oncogene Proteins c-akt / metabolism
  • Tumor Suppressor Protein p53 / metabolism*
  • Voltage-Dependent Anion Channel 1 / metabolism*
  • Xenograft Model Antitumor Assays
  • Zinc / metabolism*

Substances

  • Tumor Suppressor Protein p53
  • Voltage-Dependent Anion Channel 1
  • Hexokinase
  • AKT1 protein, human
  • Glycogen Synthase Kinase 3 beta
  • Proto-Oncogene Proteins c-akt
  • Zinc