Lanosterol synthase loss of function decreases the malignant phenotypes of HepG2 cells by deactivating the Src/MAPK

Xiaomei Sun1, Jun Zhang1, Hui Liu2

  • 1Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, Anhui 230032, P.R. China.

Oncology Letters
|June 5, 2023
PubMed

Insights

Inhibiting lanosterol synthase (LSS) in liver cancer cells reduces tumor growth and metastasis. LSS knockdown halts cell proliferation and migration by deactivating the Src/MAPK pathway.

Area of Science:

  • Oncology
  • Molecular Biology
  • Biochemistry

Background:

  • Cholesterol is essential for tumor cell membrane integrity, morphology, and function.
  • Targeting cholesterol synthesis pathways presents a potential strategy to impede tumor progression and metastasis.

Purpose of the Study:

  • To investigate the impact of inhibiting lanosterol synthase (LSS) on the biological behavior of HepG2 liver cancer cells.
  • To elucidate the underlying molecular mechanisms, including the role of the Src/MAPK signaling pathway.

Main Methods:

  • Lanosterol synthase (LSS) was inhibited using short hairpin RNA (shRNA) in HepG2 cells.
  • Cell proliferation, apoptosis, and migration were assessed using Cell Counting Kit-8, flow cytometry, and wound healing assays.
  • Protein expression and signaling pathway activity (Src/MAPK) were analyzed via western blotting.

Main Results:

  • LSS knockdown significantly inhibited HepG2 cell proliferation, inducing cell cycle arrest at the S phase.
  • Reduced cell migration and increased apoptosis were observed following LSS knockdown.
  • LSS inhibition led to decreased activity of the Src/MAPK signaling pathway.
  • Alterations in protein expression related to cell cycle, apoptosis, and migration regulation were noted.

Conclusions:

  • Lanosterol synthase knockdown reduces the malignant phenotypes of HepG2 liver cancer cells.
  • This effect is mediated by the deactivation of the Src/MAPK signaling pathway.
  • LSS inhibition represents a potential therapeutic target for liver cancer treatment.

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