Thalidomide is initially promoted as a sedative, has immunomodulatory, anti-inflammatory and anti-angiogenic cancer properties, and targets cereblon (CRBN), a part of the cullin-4 E3 ubiquitin ligase complex CUL4-RBX1-DDB1, with a Kd of ∼250 nM. Thalidomide (50 μg/mL) potentiates the anti-tumor activity of icotinib against the proliferation of both PC9 and A549 cells, and this effect is correlated with apoptosis and cell migration. In addition, Thalidomide and icotinib inhibits the EGFR and VEGF-R2 pathways in PC9 cells.