Protein kinase cAMP-activated catalytic subunit alpha (PRKACA) was proven as miR-503 target gene by luciferase assay, and it is suggested that miR-503 induced autophagy in ESCC cells via the protein kinase A (PKA)/mammalian target of rapamycin (mTOR) pathway (Wu et al., 2018). This evidence concerns the gene MTOR and esophageal squamous cell carcinoma.