Abstract
BACKGROUND: Advanced ovarian cancer involves tumor cells proliferating within ascitic fluid, which is rich in chemokines, cytokines, growth factors, and phospholipids essential for tumor progression. Tumor necrosis factor-alpha (TNF-α) and lysophosphatidic acid (LPA) are critical components that modulate ovarian tumor cell behavior in vivo, though most in vitro studies have relied on cell monolayers that do not accurately represent the tumor microenvironment. We thus investigated TNF-α and LPA effects on ovarian tumor cells cultured in collagen scaffolds, which are a model more reflective of in vivo conditions. METHODS: Ovarian cancer cell lines SKOV-3, OVCAR-8, OVCAR-5, and OVCAR-4 were cultured in collagen I hydrogels at various concentrations of TNF-α and LPA for 2-8 days. Outcomes included cell morphology, collagen topography, secretion of vascular endothelial growth factor (VEGF), interleukin-8 (IL-8), interleukin-6 (IL-6), and cell survival endpoints, with comparisons to collagen topography observed in ovarian tumor tissue. RESULTS: Collagen I fiber topography in 3D hydrogels remodeled over time, resembling the ovarian cancer tissue. LPA significantly reduced hydrogel size in SKOV-3 cells. While LPA modestly altered VEGF secretion, both LPA and TNF-α increased IL-8 secretion over time, with TNF-α also elevating IL-6 levels. TNF-α reduced cell survival in OVCAR-8 and OVCAR-5, while LPA promoted cell growth in SKOV-3, OVCAR-8, and OVCAR-5. CONCLUSIONS: TNF-α and LPA have diverse, cell line-specific effects on ovarian cancer cells in collagen hydrogels, underscoring cell line heterogeneity and the utility of 3D models.