Fig. 2: Spatial association of apoptotic cells and tumor cells provides an early survival advantage to tumor cells.
From: Apoptotic cells promote circulating tumor cell survival and metastasis
Met-1 cells were injected I.V. with acCasp8 3T3 (A, C, E) or acCasp9 Met-1 (B, F–H). Lung gDNA was harvested at the indicated timepoints for qPCR (A, B) or lungs processed for FACS at 24 h (C). Met-1 cells expressed ZsGreen (Met-1ZsG) (B, C). B16-F10 cells were injected I.V. with acCasp8 3T3 (D). Tumor cells and apoptotic cells were mixed up to 1 h in advance (mixed) or immediately prior and injected in a single bolus, or injected in two sequential injections into opposite tail veins (separate), or apoptotic cells were injected 24 h prior to tumor cell challenge (D–H). Surface lung metastasis was quantified after 14 days (D, E). Lungs were harvested 1 h after I.V. for visualization by fluorescent microscopy, acCasp9 Met-1 cells were stained with CFSE (green) and Met-1 cells expressed mCherry (red), scale bar = 200 µm (F–H). Error bars represent SEM, Dots are biological replicates (A–E) or represent distinct slices of lung tissue taken from n = 3–4 biological replicates (G, H), statistical testing is unpaired t-test (A–C, G, H) or Ordinary one-way ANOVA with Tukey’s multiple comparisons test (D, E) AC apoptotic cell, TC tumor cell.
