ANXA5 Enhances Malignancy of Murine Hepatocarcinoma Hca-P Cells <i>via</i> ERK Activation and E-cadherin Suppression

Abstract

The invasion and metastasis are linked to the rapid progression and poor prognosis of hepatocarcinoma patients. Lymphatic metastasis is potentially involved in above pathogenesis with unclear mechanism. Previously, we found the deregulation of annexin A5 (ANXA5), a member of Ca²⁺-regulated phospholipid- and membrane-binding annexin family protein, mediated the <i>in vivo</i> malignancy, lymph node metastasis (LNM) rate and level of mice transplanted with Hca-P, a murine hepatocarcinoma cell line with the LNM potential rate of ~25%. Current work aimed to investigate the influence with action mechanism of ANXA5 overexpression on the <i>in vitro</i> malignant behaviours of Hca-P cells. For overexpressing ANXA5, the <i>Anxa5</i> gene was ligated into pCDNA3.1 (+) vector and transfected into Hca-P named as Hca-P-ANXA5up. Hca-P transfected with empty pCDNA3.1 (+) vector was named as Hca-P-mock and used as the control. The monoclonal Hca-P-mock and Hca-P-ANXA5up cell lines were obtained against G418 screening using limiting dilution method. Compared with the Hca-P-mock cells, Western blotting assay indicated ANXA5 expression level was increased by 50.1% (<i>p</i>=0.025) in the Hca-P-ANXA5up cells. Transwell chamber assays indicated that the migration and invasion capacities of Hca-P-ANXA5up cells were increased by 150.2% (<i>p</i>=0.001) and 94.8% (<i>p</i>=0.003) than Hca-P-mock cells. ANXA5 overexpression enhanced the levels of p-MEK (Ser217/221), ERK1, ERK2, p-ERK1 (Thr202/Tyr204) and p-ERK2 (Thr185/Tyr187), and suppressed the levels of E-Cadherin, Snail and Slug in Hca-P cells. Current work shows ANXA5 overexpression enhances the malignant behaviours of hepatocarcinoma Hca-P cells through activating p-MEK-ERK pathway and suppressing E-Cadherin, Snail and Slug. It is of potential value in tumor malignancy and lymphatic metastasis of hepatocarcinoma.