APOE and cancer: To address the possible mechanistic roles of SPL other than via the LPI, LPG‐GPR55 axis, we checked the condition of autophagy in the cell lines, based on the positive correlations between SPL and autophagy‐related molecules in the clinical study (Table S3), the importance of autophagy in cancer progression,66, 67 the action of S1P through its receptors as an inhibitor of autophagy via activation of the mTOR pathway,48, 68 and the direct role of SPL in neuronal autophagy.69