The inhibitory effect of hsa_circ_0000515 silencing on cancer progression was observed, as indicated by decreased expression of PCNA, MMP-9, TIMP-1 and P62 in respons to hsa_circ_0000515 silencing, accompanied by elevated expression of Caspase3, Caspase9, Beclin1 and LC3, and the ratio of LC3-II/LC3-I. Here, PCNA is linked to cancer.