APOM and neoplasm: Sarkisyan et al. (2014) suggested that S1PR1 signaling could delay tumor progression by enhancing or destabilizing integrity of neovasculature. S1PR signaling pathways are also reported to be involved in the oncogenesis of various cancers including NSCLC (Zhang et al., 2018b; Zhu et al., 2018). Apolipoprotein M (ApoM) is a sphingosine 1-phosphate (S1P) carrier, which is involved in regulating S1P (Duan et al., 2001; Sevvana et al., 2009). Overexpression of ApoM could promote proliferation, invasion, and tumor growth of NSCLC cell via upregulation of S1PR1 (Zhu et al., 2018).