PLD1 inhibitor is a compound that targets phospholipase D1 (PLD1). It suppresses PLD activity in A549 cells overexpressing PLD1 with an IC50 of 1.97 µM. This inhibitor also decreases the viability of A549 lung cancer and HCT116 colorectal cancer cells, with IC50 values of 18 and 29 µM, respectively. Furthermore, it impairs proliferation, migration, and invasion of A549 cells and triggers apoptosis. Administered at 10 mg/kg every other day, PLD1 inhibitor diminishes tumor growth, induces intratumoral apoptosis, and lowers levels of Ras, CD47, CD24, and programmed cell death 1 ligand 1 (PD-L1) in a murine Lewis lung carcinoma model.