Effect of Phosphoribosyltransferase Down-regulation on Malignant Glioma Cell Characteristics

Anticancer Res. 2020 Sep;40(9):4895-4905. doi: 10.21873/anticanres.14492.

Abstract

Background/aim: Nicotinamide phosphoribosyl-transferase (NAMPT) is a rate-limiting enzyme in the pathway synthesizing nicotinamide adenine dinucleotide (NAD (+)) from nicotinamide (NAM). Glioma tissues exhibit up-regulated NAMPT expression associated with a poor prognosis of patients. To determine if NAMPT can be a molecular therapeutic target, we investigated the effects of short hairpin RNA (shRNA)-mediated NAMPT down-regulation.

Materials and methods: We designed shRNA to NAMPT and transfected to T98G cells. The characteristics of these cells were analyzed.

Results: The NAMPT shRNA-transfected cells exhibited delayed cell growth. However, there was no difference in the increase of sensitivity to temozolomide (TMZ) or X-ray irradiation between the NAMPT and scramble shRNA-transfected cells. The expression of NAMPT in the NAMPT shRNA-transfected cells increased with cell passage. Additionally, the shRNA-mediated transfection was associated with enhanced expression of quinolinic acid phosphoribo-syltransferase (QPRT).

Conclusion: shRNA-mediated NAMPT down-regulation may not decrease the NADt to a sufficient level to increase TMZ/radiation sensitivity.

Keywords: Nicotinamide phosphoribosyltransferase; glioma; shRNA.

MeSH terms

  • Antineoplastic Agents, Alkylating / pharmacology
  • Cell Line, Tumor
  • Cell Proliferation
  • Cytokines / genetics
  • Cytokines / metabolism*
  • Down-Regulation*
  • Glioma / enzymology*
  • Glioma / metabolism
  • Glioma / pathology
  • Humans
  • NAD / metabolism
  • Nicotinamide Phosphoribosyltransferase / genetics
  • Nicotinamide Phosphoribosyltransferase / metabolism*
  • Pentosyltransferases / genetics
  • Pentosyltransferases / metabolism
  • RNA, Small Interfering / genetics
  • Temozolomide / pharmacology

Substances

  • Antineoplastic Agents, Alkylating
  • Cytokines
  • RNA, Small Interfering
  • NAD
  • Pentosyltransferases
  • Nicotinamide Phosphoribosyltransferase
  • nicotinamide phosphoribosyltransferase, human
  • nicotinate-nucleotide diphosphorylase (carboxylating)
  • Temozolomide