FOXO1 inhibits PDAC cell proliferation. (A, B) mRNA and protein levels of FOXO1 are significantly upregulated in FOXO1-overexpressing BXPC3 and PANC1 cell lines. (C, D) CCK-8 cell viability assays revealed that ectopic expression of FOXO1 significantly inhibits BxPC3 (C) and PANC1 (D) cell proliferation. (E) Xenograft tumor formation assays showed that overexpression of FOXO1 inhibits subcutaneous tumor formation capacity. (F, G) Tumor growth (F) and tumor weight (G) of xenografts of FOXO1-overexpressing PANC1 stable cells in nude mice. (H) IHC staining revealed that the expression of FOXO1 and PCNA in PANC1 stable cells induced tumor formation. (I, J) Matrigel-coated Transwell assays showed that overexpression of FOXO1 inhibits BxPC3 (I) and PANC1 (J) cell invasion. (K, L) Images showing intrahepatic metastasis (K) and morphological characters by HE staining (L), **P < 0.01. All assays were conducted in triplicate.