Down-regulating NQO1 promotes cellular proliferation in K562 cells via elevating DNA synthesis

Life Sci. 2020 May 1:248:117467. doi: 10.1016/j.lfs.2020.117467. Epub 2020 Feb 24.

Abstract

Background: NQO1 protein acts as a cellular protective system, on account of its role as a quinone reductase and redox regulator. Nonetheless, new NQO1 roles are emerging-including its regulation of the cellular proliferation of many tumor cells-and this enzyme has been found to relate to the incidence of various diseases, including chronic myeloid leukemia. However, the mechanisms through which NQO1 influences leukemia progression remain unclear.

Martial and methods: The current study looks to name NQO1 as a novel molecular target that modulates DNA synthesis and chronic myeloid leukemia growth.

Results and conclusion: Our results indicate that the frequency of the T allele of NQO1 polymorphism in chronic myeloid leukemia patients is higher than that among healthy East Asian individuals (0.492 vs. 0.419) and much higher than the average level of the general population (0.492 vs. 0.289) (1000 Genomes). Functionally, NQO1 knockdown increases the protein expression of the TOP2A and MCM complex, and consequently promotes DNA synthesis and K562 cell growth. NQO1 knockdown also promotes tumorigenesis in a xenograft model. NQO1 overexpression, on the other hand, was found to have the opposite effects.

Significance: Our results show that NQO1 downregulation promotes K562 cellular proliferation via the elevation of DNA synthesis.

Keywords: Cellular proliferation; Chronic myeloid leukemia; DNA synthesis; MCM protein complex; NQO1; TOP2A.

MeSH terms

  • Adult
  • Alleles
  • Animals
  • Asian People
  • Cell Line, Tumor
  • Cell Proliferation
  • DNA Topoisomerases, Type II / genetics
  • DNA Topoisomerases, Type II / metabolism
  • DNA, Neoplasm / biosynthesis
  • DNA, Neoplasm / genetics*
  • Female
  • Gene Expression Regulation, Leukemic*
  • Heterografts
  • Humans
  • K562 Cells
  • Leukemia, Myelogenous, Chronic, BCR-ABL Positive / ethnology
  • Leukemia, Myelogenous, Chronic, BCR-ABL Positive / genetics*
  • Leukemia, Myelogenous, Chronic, BCR-ABL Positive / metabolism
  • Leukemia, Myelogenous, Chronic, BCR-ABL Positive / pathology
  • Leukocytes / metabolism*
  • Leukocytes / pathology
  • Male
  • Mice
  • Mice, Nude
  • Middle Aged
  • NAD(P)H Dehydrogenase (Quinone) / antagonists & inhibitors
  • NAD(P)H Dehydrogenase (Quinone) / genetics*
  • NAD(P)H Dehydrogenase (Quinone) / metabolism
  • Poly-ADP-Ribose Binding Proteins / genetics
  • Poly-ADP-Ribose Binding Proteins / metabolism
  • Polymorphism, Genetic
  • RNA, Small Interfering / genetics
  • RNA, Small Interfering / metabolism
  • Signal Transduction

Substances

  • DNA, Neoplasm
  • Poly-ADP-Ribose Binding Proteins
  • RNA, Small Interfering
  • NAD(P)H Dehydrogenase (Quinone)
  • NQO1 protein, human
  • DNA Topoisomerases, Type II
  • TOP2A protein, human