Knockdown of Lymphoid Enhancer-binding Factor 1 Inhibits Pancreatic Adenocarcinoma Growth and Neoangiogenesis by Curbing Notch1 and Nuclear Factor Kappa B Signaling Pathways.

[OBJECTIVES] To investigate the impaction of LEF1 for malignant development of pancreatic adenocarcinoma (PAAD) and its specific mechanisms.

[MATERIALS AND METHODS] The expression of LEF1 in PAAD and normal tissues was inspected by bioinformatics, qRT-PCR, and western blot (WB). AsPC-1 and BxPC-3 were selected for further knockdown study. The post-knockdown cellular malignant progression was evaluated by CCK-8, EdU, clonogenic assay, wound healing, Transwell, Calcein AM/PI staining, and LDH release assays. Conditioned medium (CM) of PAAD after LEF1 knockdown was collected to culture HUVEC for evaluating the effect on angiogenesis. Immunofluorescence assay and WB were employed to detect the changes of Notch1 and NF-κB pathway. Finally, a nude mouse tumor xenograft model was established to verify the in vivo suppressive effect of knocking down LEF1 on PAAD.

[RESULTS] LEF1 is highly expressed in PAAD. The proliferation, migration, and invasion of AsPC-1/sh-LEF1 and BxPC-3/sh-LEF1 were inhibited, and the apoptosis was significantly increased. The CM of AsPC-1/sh-LEF1 and BxPC-3/sh-LEF1 significantly inhibited HUVEC migration and angiogenesis. The intranuclear expression of Notch1, NICD, Hes1, and P65 proteins were reduced, indicating that LEF1 downregulation inhibited the activation of the Notch1 and NF-κB. Finally, the inhibitory effect of LEF1 downregulation on PAAD growth was further verified in vivo, confirming the important role of LEF1 in PAAD development.

[CONCLUSIONS] Knockdown of LEF1 can inhibit the growth and neoangiogenesis of PAAD by inhibiting Notch1 and NF-κB, thus inhibiting the malignant progression of PAAD.