Cancer-associated fibroblast exosomes promote prostate cancer metastasis through miR-500a-3p/FBXW7/HSF1 axis under hypoxic microenvironment

Cancer Gene Ther. 2024 May;31(5):698-709. doi: 10.1038/s41417-024-00742-2. Epub 2024 Feb 14.

Abstract

Metastasis is the main cause of deaths in prostate cancer (PCa). However, the exact mechanisms underlying PCa metastasis are not fully understood. In this study, we discovered pronounced hypoxia in primary lesions of metastatic PCa(mPCa). The exosomes secreted by cancer-associated fibroblasts (CAFs) under hypoxic conditions significantly enhance PCa metastasis both in vitro and in vivo. Through miRNA sequencing and reverse transcription quantitative PCR (RT-qPCR), we found that hypoxia elevated miR-500a-3p levels in CAFs exosomes. Subsequent RT-qPCR, western blotting, and dual luciferase reporter assays identified F-box and WD repeat domain-containing 7(FBXW7) as a target of miR-500a-3p. In addition, immunohistochemistry revealed that FBXW7 expression decreased with the progression of PCa, while heat shock transcription factor 1(HSF1) expression increased. Introducing an FBXW7 plasmid into PCa cells reduced their metastatic potential and significantly lowered HSF1 expression. These findings suggest that CAFs exosomes drive PCa metastasis via the miR-500a-3p/FBXW7/HSF1 axis in a hypoxic microenvironment. Targeting either hypoxia or exosomal miR-500a-3p could be a promising strategy for PCa management.

MeSH terms

  • Animals
  • Cancer-Associated Fibroblasts* / metabolism
  • Cancer-Associated Fibroblasts* / pathology
  • Cell Line, Tumor
  • Exosomes* / genetics
  • Exosomes* / metabolism
  • F-Box-WD Repeat-Containing Protein 7* / genetics
  • F-Box-WD Repeat-Containing Protein 7* / metabolism
  • Gene Expression Regulation, Neoplastic
  • Heat Shock Transcription Factors / genetics
  • Heat Shock Transcription Factors / metabolism
  • Humans
  • Hypoxia / genetics
  • Hypoxia / metabolism
  • Male
  • Mice
  • MicroRNAs* / genetics
  • MicroRNAs* / metabolism
  • Neoplasm Metastasis*
  • Prostatic Neoplasms* / genetics
  • Prostatic Neoplasms* / metabolism
  • Prostatic Neoplasms* / pathology
  • Tumor Microenvironment*

Substances

  • F-Box-WD Repeat-Containing Protein 7
  • FBXW7 protein, human
  • MicroRNAs
  • MIRN500 microRNA, human
  • HSF1 protein, human
  • Heat Shock Transcription Factors