Objective  In order to observe the expression level of armadillo repeat con-taining protein 8 (ARMC8) in gastric cancer (GC) tissues, plasma and cell lines, and to explore the molecular mechanism of ARMC8 on invasion, migration and epithelial-mesenchymal transition (EMT) of GC cells.

Methods  The differential expressions of ARMC8 in 408 GC tissues and 211 normal tis-sues were analyzed from GEPIA database. The expression of ARMC8 in the plasma of GC patients and healthy people was analyzed by quantitative real-time PCR (qRT-PCR). The expression of ARMC8 was further validated in two GC cell lines (HGC-27, AGS) and one normal gastric mucosal epithelial cell (GES-1). The expression level of ARMC8 was downregulated by transfection with si-ARMC8 and nega-tive control (NC). The abilities of migration and invasion of GC cells were determined by wound heal-ing assay and Transwell assay after transfection. The effect of downregulation of ARMC8 expression on EMT-associated proteins and the activation of Wnt/β-catenin signaling was measured by WB.

Results  The expression of ARMC8 was significantly elevated in GC tissues plasma and GC cell lines; Transwell invasion assay and wound healing results showed that downregulation of ARMC8 inhibited GC cell invasion and migration ability. Downregulation of ARMC8 inhibited the EMT process and the activation of Wnt/β-catenin signaling pathway in GC cells.

Conclusion  ARMC8 is highly expressed in GC tissues, the plasma of GC patients and GC cell lines, and which may play a key role in migration invasion and EMT of GC via Wnt/β-catenin signaling.

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