PTEN and gastric cancer: Amplifications of JAK2, CD274, PDCD1LG2, and ERBB2 have also been detected in EBV-positive GC cases, as well as deletions in PTEN, SMAD4, CDKN2A, and ARID1A. The JAK/STAT signaling play an important role in proliferation, differentiation and apoptosis and has been intensely investigates in gastric cancer [50] and increased expression of PD-L1 has been correlated with poor prognosis in the GC cases, potentially contributing to immune suppression and evasion [51, 52].