FIG. 8.

Cathepsin L in breast cancer cells has a direct effect on capillary sprouts and vascular densities in the microvasculature during angiogenesis. Bioprinted nontarget, NT, (A, B) or cathepsin L knockdown, KD, (D, E) 4T1 murine breast cancer cells onto wild-type mesometrium tissues were cultured ex vivo for 5 days. Tissues with cells were fixed in methanol and labeled against PECAM to identify endothelial cells lining the microvasculature. Both groups were angiogenic indicative of the capillary sprouts (arrows). After 5 days in culture, the number of capillary sprouts (C) and vascular segments (F) were quantified for the nontarget cancer cells (black circle symbol) and the cathepsin L KD cancer cells (blue triangle symbol). Data are shown as the mean ± SEM and * represents p < 0.05, n = 7. Scale bars = 100 μm.