PTK2 and gastric cancer: The orthotopic tumor transplantation model showed that when the FAK gene expression was silenced by RNAi technology, the metastasis of gastric cancer in nude mice was inhibited, which further confirmed that FAK plays an important role in the process of tumor metastasis, suggesting that orthotopic tumor transplantation may better present the biological characteristics of SGC-7901 cells in the event of metastasis.