In order to evaluate the effect of FA + ASP chemopreventive regimens on tumor cell proliferation, immunohistochemistry (IHC) was performed to measure the expression of cell proliferation markers proliferating cell nuclear antigen (PCNA; Fig. 5a, c) and MKI67 (Fig. 5b, d) on pancreatic tissues. The gene discussed is MKI67; the disease is neoplasm.