Thus, firstly the effects of PARP1 on the cell proliferation of A549, H1975 and PC9 were tested through MTT assays. The result indicated that PARP1 gene silence could significantly inhibit the cell growth of A549, H1975 and PC9, while PARP1 overexpression promoted the growth of A549 cell significantly (Figure 6). Secondly, cell scratch test would be conducted to identify whether PARP1 could promote the metastatic capacity of NSCLC. The result showed that PARP1 silence inhibited cell migration significantly shown in cell scratch test, while PARP1 overexpression promoted migration of NSCLC cell significantly (Figure 7). Finally, trans-well assays (Figure 8) was adopted to confirm these results, with the same conclusion drawn.