We found that knockdown of IARS2 inhibited the proliferation and clonal formation of A549 and H1299 cells, promoted apoptosis, and induced cell cycle arrest in A549 cells (G0/G1 phase) and H1299 cells (S phase), indicating that it affects DNA and protein synthesis, proliferation, and division in lung cancer cells. The gene discussed is IARS2; the disease is lung carcinoma.