PCNA and neoplasm: Molecular analysis of the tumor tissues showed that melatonin decreased the levels of p-Akt, p-ERK, cyclin D1, PCNA, Bcl-2, Vimentin, Snail, HIF-1α, and VEGF, but upregulated the expressions of Bax and E-cadherin (Figures 5(e) and 5(f)).