Lipid droplet storage promotes murine pancreatic tumor growth

Oncol Rep. 2021 Apr;45(4):21. doi: 10.3892/or.2021.7972. Epub 2021 Mar 2.

Abstract

Hypoxia Inducible Lipid Droplet Associated (HILPDA) is frequently overexpressed in tumors and promotes neutral lipid storage. The impact of Hilpda on pancreatic ductal adenocarcinoma (PDAC) tumor growth is not known. In order to evaluate Hilpda‑dependent lipid storage mechanisms, expression of Hilpda in murine pancreatic cells (KPC) was genetically manipulated. Lipid droplet (LD) abundance and triglyceride content in vitro were measured, and model tumor growth in nu/nu mice was determined. The results showed that excess lipid supply increased triglyceride storage and LD formation in KPC cells in a HILPDA‑dependent manner. Contrary to published results, inhibition of Adipose Triglyceride Lipase (ATGL) did not ameliorate the triglyceride abundance differences between Hilpda WT and KO cells. Hilpda ablation significantly decreased the growth rate of model tumors in immunocompromised mice. In conclusion, Hilpda is a positive regulator of triglyceride storage and lipid droplet formation in murine pancreatic cancer cells in vitro and lipid accumulation and tumor growth in vivo. Our data suggest that deregulated ATGL is not responsible for the absence of LDs in KO cells in this context.

Keywords: lipid; hypoxia; pancreatic.

MeSH terms

  • Animals
  • Carcinoma, Pancreatic Ductal / metabolism*
  • Carcinoma, Pancreatic Ductal / pathology
  • Cell Growth Processes / physiology
  • Lipid Droplets / metabolism*
  • Lipid Metabolism
  • Mice
  • Neoplasm Proteins / metabolism*
  • Pancreatic Neoplasms / metabolism*
  • Pancreatic Neoplasms / pathology

Substances

  • HIG2 protein, mouse
  • Neoplasm Proteins