PCNA and neoplasm: Correlation with the aim to investigate the effect of cannabinoids on the human PDAC xenograft tumors via the mechanism of tumor cell death, IHC was carried out to detect the expression of proliferative markers (Ki-67 and PCNA), and apoptotic–related markers (BAX, BCL-2, Caspase-3, Caspase-8, and p53) (Fig. 3a,d).