PTENP1 and hepatocellular carcinoma: On the contrary, other lncRNAs, such as the phosphatase and tensin homolog pseudogene 1 (PTENP1), which has been found downregulated in HCC, could act as tumor suppressors by activating autophagy and promoting autophagic cell death of tumor cells and inhibiting migration, invasion, and angiogenesis [113].