CCK-8 assay was used to detect cell proliferation after cells were treated with 60% H2 for 12, 24, 36, 48 and 72 h in (A) A549 and (B) H1975 cells. (C) Cell invasion ability was determined by using the Transwell chambers after 48 h of cell treatment with 60% H2. (D,E) Wound healing assay was used to assess cell migration ability after 24 h of cell treatment with 60% H2. (F) The effects of H2 treatment on cell apoptosis were determined by flow cytometry assay in A549 and H1975 cells. (G) Western blotting was carried out to detect the expressions of Bcl-2, cleaved caspase3, caspase3, cleaved PARP and PARP after 48 h of cell treatment with 60% H2 (*P<0.05, **P<0.01).