Splenic serum from portal hypertensive patients enhances liver stem cell proliferation and self-renewal via the IGF-II/ERK signaling pathway

Dig Liver Dis. 2020 Feb;52(2):205-213. doi: 10.1016/j.dld.2019.07.014. Epub 2019 Sep 5.

Abstract

Background: Hypersplenism is a serious complication of portal hypertension (PH) and can affect the prognosis of liver disease. Liver stem cells (LSCs) are involved in liver regeneration and hepatocarcinogenesis after liver cirrhosis.

Aim: To explore the effects and mechanism of the spleen on the proliferation and differentiation of LSCs in PH due to liver cirrhosis.

Methods: Fetal liver stem cells (FLSCs) were treated with splenic serum from liver cirrhosis patients with hypersplenism and control serum from healthy volunteers, and the proliferation, self-renewal, and IGF-II/ERK signaling pathway of FLSCs were then evaluated.

Results: We found that splenic serum from PH patients promoted FLSC proliferation, colony formation, and Ki-67 expression in vitro. Splenic serum from PH also enhanced FLSC spheroid formation in vitro. Mechanistically, we determined that insulin-like growth factor (IGF)-II concentration was elevated in splenic serum from PH patients and could promote FLSC proliferation and self-renewal. Furthermore, both IGF-II and splenic serum from PH patients enhanced ERK signaling activation through IGF-I receptor (IGF-I R) in FLSCs. Consistently, blocking IGF-I R or ERK signaling could attenuate the effects of splenic serum from PH patients on FLSCs.

Conclusions: The spleen in PH patients promotes FLSC proliferation and self-renewal through the IGF-II/ERK signaling pathway.

Keywords: Carcinogenesis; Cell proliferation; Differentiation; Liver cirrhosis.

MeSH terms

  • Adult
  • Animals
  • Case-Control Studies
  • Cell Differentiation
  • Cell Proliferation
  • Cell Self Renewal*
  • Cells, Cultured
  • Female
  • Humans
  • Hypertension, Portal / blood*
  • Insulin-Like Growth Factor II / metabolism*
  • Liver / blood supply
  • Liver / cytology
  • Liver / embryology
  • Liver Cirrhosis / blood*
  • MAP Kinase Signaling System*
  • Male
  • Mice, Inbred C57BL
  • Middle Aged
  • Receptor, IGF Type 1 / metabolism*
  • Serum
  • Spleen / blood supply
  • Stem Cells / cytology
  • Young Adult

Substances

  • IGF2 protein, human
  • Insulin-Like Growth Factor II
  • Receptor, IGF Type 1