{
  "id": 3506053,
  "title": "Ovarian cancer ascites is enriched in Tim4+ macrophage-derived extracellular vesicles carrying a translation-related proteomic signature",
  "url": "https://urgent.news/2026/08/26/ovarian-cancer-ascites-is-enriched-in-tim4-macrophage-derived",
  "topic": "health",
  "section": "Health & Medicine",
  "published": "2026-08-26T00:00:00.000Z",
  "source": {
    "name": "bioRxiv",
    "slug": "biorxiv",
    "url": "https://www.biorxiv.org/content/10.64898/2026.08.25.747110v1?rss=1"
  },
  "original_language": "en",
  "account": "Ovarian cancer (OvCa) is the leading cause of gynecological cancer deaths, primarily due to late diagnosis and widespread spread within the peritoneal cavity. High-grade serous ovarian cancer (HGSOC), the most common type, often spreads through the peritoneum, leading to increased metastasis and poor prognosis. Malignant ascites, a fluid accumulation in the abdominal cavity, is linked to elevated cancer spread and worse patient outcomes. This complex environment within ascites contains various cell types, soluble factors, and extracellular vesicles (EVs), which may facilitate cell-to-cell communication and disease progression. To better understand these EVs, researchers examined both human and mouse ovarian cancer ascites, focusing on macrophage-linked EVs. Proteomic investigation of a human EV sample from malignant ascites revealed an overrepresentation of proteins associated with myeloid and macrophage cells. Within a controlled mouse model of ID8 ovarian cancer, researchers discovered that CD9+ EVs, which include CD9+CD63+CD81+ EVs, were more prevalent in the cell-free peritoneal fluid of tumor-bearing mice. Macrophages were the most common CD9+ cells in the ascites. When examining the proteins present on these CD9+ EVs, scientists found an abundance of macrophage-linked proteins and an enrichment of ribosomal proteins. The research also identified Tim4+ membrane-stain-positive, detergent-sensitive EVs that were more abundant in tumor-bearing mice. These Tim4+ EVs exhibited a protein profile enriched in ribosomal and other translation-related proteins. Additionally, the study found a separate membrane-stain-negative, detergent-resistant Tim4+ particle population that was also increased in ovarian cancer ascites. The findings represent the first identification of EV-associated and non-EV particle-associated Tim4 protein in ovarian cancer ascites. Overall, these results highlight the presence of macrophage-associated EV signatures in ovarian cancer ascites and demonstrate a consistent increase in ribosome- and translation-related EV cargo across human and mouse ascites samples.",
  "summary": "Ovarian cancer (OvCa) remains the leading cause of gynecological cancer mortality, largely due to late-stage diagnosis and extensive peritoneal dissemination. High-grade serous ovarian cancer (HGSOC), the most prevalent subtype, commonly disseminates throughout the peritoneal cavity, where malignant ascites is associated with increased metastatic burden and poor clinical outcomes. Malignant…",
  "key_points": [],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}