Then, 92-shRAC2 and OCM-RAC2, with RAC2 knock-down in 92-1 cells and radiation-inducible RAC2 overexpression in OCM-1 cells respectively, as well as their negative control cell lines (92-NC and OCM-NC) were established by corresponding lentivirus infection and puromycin selection. The gene discussed is RAC2; the disease is lentivirus infection.