Figure 3. 15-LOX-1 Inhibits Colonic Stem Cell Self-Renewal in Intestinal Epithelial Cells of Apc^Δ580 Mice and Human Colorectal Cancer Cells.

(A–C) Apc^Δ580 and Apc^Δ580-15-LOX-1 littermates were euthanized at 6 weeks and isolated colonic mucosa cells from two littermates (Lm) of the indicated mice were cultured for primary organoids for 8 days and then analyzed for LRP5, active β-catenin, and 15-LOX-1 protein expression levels (A), as well as Axin2 (B) and cyclin D1 (C) mRNA expression.

(D–F) Primary (P0) (D) and secondary (P1) (E) organoid formation efficacies at 8 days of culture. (F) Representative bright-field light microscopic (P0 and P1) and hematoxylin and eosin (H&E) staining of images (P1) of organoids for the indicated mice.

(G–L) LRP5, active β-catenin, 15-LOX-1, Axin1, and cyclin D1 protein expression levels, measured using western blot analysis (G); immunofluorescence staining images of active β-catenin (H); and mRNA expression of Axin2 (I) and cyclin D1 (J) measured using reverse transcription real-time quantitative polymerase chain reaction performed in triplicate in human colorectal cancer tissue-derived organoid cells transduced with control (Ctrl) or 15-LOX-1 lentivirus for at least five passages. (K) Organoid formation efficacies and (L) representative bright-field light microscopic images of human colorectal cancer tissue-derived organoids transduced with either control or 15-LOX-1 lentivirus (n = 6 cases).

Values are mean ± SEM. *p < 0.05, **p < 0.01, ***p < 0.001, and ****p < 0.0001; unpaired t test (B–E, I–K).