PPM1G promotes autophagy and progression of pancreatic cancer via upregulating HMGB1

Cell Signal. 2024 Nov:123:111342. doi: 10.1016/j.cellsig.2024.111342. Epub 2024 Aug 8.

Abstract

Pancreatic cancer remains one of the most aggressive and lethal malignancies worldwide, with a dismal 5-year relative survival rates of only 12%. Therefore, it is urgent to discover the key molecular markers to improve the therapeutic outcomes in pancreatic cancer. Herein, we first demonstrated that PPM1G is upregulated in pancreatic cancer and that PPM1G depletion decreases pancreatic cancer cell growth in vitro and in vivo. High PPM1G expression was linked to short overall survival of pancreatic cancer patients, which was further validated in the TCGA database. Moreover, by detecting Beclin 1, LC3-II, and SQSTM1/p62 expressions and observing autolysosome under transmission electron microscope, we discovered that PPM1G is a novel positive regulator of macroautophagy/autophagy. Furthermore, by using immunoprecipitation-mass spectrometry (IP-MS) analysis and following systemic molecular biology experiment, we demonstrated PPM1G promotes the autophagy and proliferation of pancreatic cancer by directly upregulating HMGB1. Additionally, patients with both high PPM1G and high HMGB1 exhibited poorer prognosis in our cohort. This study preliminarily investigated the possibility of PPM1G as a potential therapeutic target and prognostic biomarker in pancreatic cancer patients.

Keywords: Autophagy; HMGB1; PPM1G; Pancreatic cancer; Progression.

MeSH terms

  • Animals
  • Autophagy*
  • Cell Line, Tumor
  • Cell Proliferation*
  • Disease Progression
  • Female
  • Gene Expression Regulation, Neoplastic
  • HMGB1 Protein* / genetics
  • HMGB1 Protein* / metabolism
  • Humans
  • Male
  • Mice
  • Mice, Nude
  • Pancreatic Neoplasms* / genetics
  • Pancreatic Neoplasms* / metabolism
  • Pancreatic Neoplasms* / pathology
  • Prognosis
  • Protein Phosphatase 2C* / genetics
  • Protein Phosphatase 2C* / metabolism
  • Up-Regulation

Substances

  • HMGB1 Protein
  • HMGB1 protein, human
  • Protein Phosphatase 2C
  • PPM1G protein, human