PTK2 and gastric cancer: As for THBS4, its potential role and prognostic performance in melanoma remains unclear but it is linked to poor prognosis in many other cancers: it effects the amplification and metastasis of gastric cancer positively (62); it may facilitate invasion of tumour cells in breast cancer (63); it accelerates HCC progression by modulating ITGB1 through FAK/PI3K/AKT pathway (64).