YAP1 knockdown suppresses the proliferation, migration and invasion of human nasopharyngeal carcinoma cells

Abstract

To investigate the effects of Yes-associated protein 1 (YAP1) knockdown on the proliferation, migration and invasion in human nasopharyngeal carcinoma (NPC) cells. We detected the expression of YAP1 mRNA and protein in different NPC cell lines and an immortalized nasopharyngeal epithelial cell line using RT-PCR and Western blotting. Two YAP1-targeting small interfering RNAs (siRNA) were transfected into NPC cell lines S26 and S18, and the knockdown efficiency was confirmed by RT-PCR and Western blotting. The effect of YAP1 knockdown on the proliferation of the NPC cells was determined by cell counting and colony formation assay; wound healing assay and Transwell assay were used to analyze the changes in the cell migration and invasion abilities in each group. Western blotting was used to analyze the changes in the expressions of c-myc, E-cadherin, N-cadherin and vimentin in the NPC cells after YAP1 knockdown. YAP1 was highly expressed in the NPC cell lines. Compared with the negative control group, the NPC cell lines with YAP1 knockdown showed significantly lowered YAP1 expressions at both the mRNA and protein levels (P < 0.05). YAP1 knockdown significantly suppressed the growth, cloning formation, migration and invasion of the NPC cells as compared with control cells (P < 0.01). YAP1 knockdown obviously decreased the expression levels of c-myc, N-cadherin and vimentin and increased E-cadherin expression in the NPC cells. YAP1 knockdown via siRNA suppresses the proliferation, migration and invasion of NPC cells in vitro, suggesting that YAP1 may serve as a therapeutic target for NPC.