Aim: To develop a realistic 3D tumor-infiltration model (TM) that mimics ovarian tissue contaminated with cancer cells, aimed at cellular analysis and drug screening applications.3 Methods: Ovarian stromal cells (SCs) and acute myeloid leukemia cells (HL-60) were combined in four specific ratios (1:1, 1:10, 1:100, and 1:1000) (Fig. 1a) and embedded within a hydrogel matrix designed to mimic extracellular conditions 1. The hydrogel’s structural properties and cytocompatibility were assessed using scanning electron microscopy (SEM) (Fig. 1b) and LIVE/DEAD viability assays (Fig. 1c,d). Cancer cell identification, as well as proliferation and density dynamics, were analyzed through immunofluorescence targeting CD43 and Ki-67 (Fig. 1e). Additionally, the persistence of malignant cells within the TMs was verified using reverse transcription polymerase chain reaction (RT-PCR) to confirm tumor-specific gene expression. Results: The hydrogel matrix successfully supported the proliferation of both cell types without cytotoxic effects. By the third day, in the TM group with an HL-60 to SC ratio of 1:1, the SC proliferation rate was limited to 6.33 ± 1.96%, significantly lower than that observed in the fourth group. This finding suggests that when HL-60 cells are present at the same concentration as SCs, they can inhibit SC proliferation. This influence is likely due to nutrient competition, as myeloid cells are known to consume notably high glucose levels. At HL-60:SC ratios of 1:1 and 1:10, proliferation rates increased significantly compared to baseline (Day 0), likely due to cell-cell interactions and microenvironmental factors. In contrast, the 1:1000 ratio group showed no detectable cancer cell proliferation, possibly due to the inhibitory influence of mesenchymal stem cells within the ovarian SCs 2. Possessing immunomodulatory and anti-tumor properties, these cells are known for their ability to inhibit tumor growth by secreting various cytokines and chemokines, which modulate the immune response and potentially induce apoptosis in malignant cells 3. The 1:100 HL-60:SC ratio provided the most accurate model of leukemia cell infiltration into ovarian tissue, as malignant cell activity remained stable over the five-day culture period, showing consistent cell density and proliferation dynamics.
Moghassemi et al. (Wed,) studied this question.