STAT3 and cancer: Another study suggests that OP-D can induce apoptosis and exert anti-tumor effects by inhibiting of signal transducer and activator of transcription 3 (STAT3) signaling pathways in non-small cell lung carcinoma (NSCLC) cells (Lee et al., 2018a) (The potential anti-cancer effects and mechanisms of OP-D are shown in Figure 3).