MKI67 and neoplasm: As observed for early S115 lesions, treatment with ARPCA (i.p. at 100 mg/kg every other day) impaired FGFR1 activation in TRAMP-C2 alginate plugs, thus leading to a decrease of the tumor cell proliferation rate (as assessed by Ki67 immunostaining) and of CD31-positive tumor vascularization (Figure 5A).