Malignant ascites-derived exosomes promote peritoneal tumor cell dissemination and reveal a distinct miRNA signature in advanced gastric cancer

Cancer Lett. 2019 Aug 10:457:142-150. doi: 10.1016/j.canlet.2019.04.034. Epub 2019 May 8.

Abstract

Peritoneal dissemination (PD) is the most frequent metastasis with poor prognosis in patients with advanced gastric cancer (GC). However, the molecular mechanisms of PD remain poorly defined. Exosomes play a pivotal role in cancer progression. Thus, this study aims to investigate the effects of malignant ascites (MA)-derived exosomes from GC patients on tumor cells and to elucidate the underlying mechanism. In vitro and in vivo analysis showed that compared to exosome-depleted supernatants, exosomes from MA of GC patients promoted invasion of AGS cells by up-regulation of Epithelial-mesenchymal transition (EMT) signaling. In a mouse abdominal xenograft model, the median survival was shorter after MA-derived exosomes treatment than the control group (35.5 days versus 67 days, p = 0.0005). Moreover, 29 exosomal miRNAs from ascites were identified by high throughput sequencing among 8 paired GC patients before and after peritoneal chemotherapy and 3 individuals with non-malignant disease. In summary, MA-derived exosomes from patients with GC promote EMT signaling in GC cells and in mouse peritoneal tumor model. Differential exosomal miRNAs might be targeted therapeutically for inhibiting peritoneal metastasis, which provides new insights for the molecular mechanisms of PD in GC.

Keywords: Ascitic fluid; Exosomal miRNA; Gastric cancer; Peritoneal metastasis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Ascites / genetics*
  • Ascites / metabolism
  • Ascites / pathology
  • Cell Line, Tumor
  • Cell Movement
  • Disease Progression
  • Epithelial-Mesenchymal Transition
  • Exosomes / genetics*
  • Exosomes / metabolism
  • Exosomes / pathology
  • Female
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Mice, Inbred NOD
  • Mice, SCID
  • MicroRNAs / genetics*
  • MicroRNAs / metabolism
  • Neoplasm Invasiveness
  • Peritoneal Neoplasms / genetics*
  • Peritoneal Neoplasms / metabolism
  • Peritoneal Neoplasms / secondary
  • Signal Transduction
  • Stomach Neoplasms / genetics*
  • Stomach Neoplasms / metabolism
  • Stomach Neoplasms / pathology
  • Time Factors
  • Transcriptome*

Substances

  • MicroRNAs