α-Fetoprotein contributes to the malignant biological properties of AFP-producing gastric cancer.

This study aimed to investigate whether α-fetoprotein (AFP) could affect the malignant behavior of AFP-producing gastric cancer (AFP-GC) and to explore the relationship between AFP and mesenchymal-epithelial transition factor (c-Met) in AFP-GC. In this study, 23 patients with AFP-GC (AFP[+]) and 18 patients with common gastric cancer (AFP[-]) were evaluated for the c-Met expression using immunohistochemical analysis. The AFP-GC cell line, GCIY, was used. The AFP endoribonuclease-prepared small interfering RNA (siRNA) and eukaryotic AFP overexpression vector were used to increase/knockdown the expression of AFP. Afterward, the c-Met expression was evaluated by polymerase chain reaction and western blot. The proliferation, migration, and invasion of GCIY cells were estimated before and after the AFP overexpression/knockdown. The c-Met expression in both groups was the same ( > 0.05), and AFP[+] group had a higher positive incidence of the c-Met expression than the AFP[-] group ( < 0.01). Furthermore, the c-Met expression frequency was decreased by AFP knockdown and increased by AFP overexpression ( < 0.01). The cell counting kit-8 cell proliferation assay, cell invasion, and migration assays confirmed that the AFP could affect the malignant biological behavior of AFP-GC. These findings suggest that AFP contributes to the malignant biological properties of AFP-GC and the high expression of c-Met in AFP-GC.