Additionally, knockdown of FEZF1-AS1 dramatically increased 5-FU sensitivity of GC cells in vivo as evidenced by the tumor growth was dramatically slower in the mice of the sh-FEZF1-AS1-SGC7901 group compared to the sh-NC-SGC7901 group after 5-FU treatment (Figures 6A,B). The gene discussed is FEZF1; the disease is neoplasm.