H2AX and lung cancer: Through in vitro and in vivo studies to explore the apoptotic mechanism and combinatorial potential of PGG with cisplatin in cisplatin-resistant lung cancer cells, it can be concluded that PGG induces apoptosis in cisplatin-resistant NSCLCs via the upregulation of DNA damage proteins such as γ-H2AX, pCHK2 and p53 and the inhibition of anti-apoptotic proteins through combination with cisplatin in cisplatin-resistant NSCLCs.