Figure 4.

PDGF-β cooperates with SCCRO to produce poorly differentiated glioblastoma. (A) Although no significant change in overall incidence was observed, tumors induced by RCAS-PDGF-β alone were primarily low grade, whereas those induced by in combination with RCAS-SCCRO were high grade (Fisher exact test, P = .03). (B) Brain sections of mice infected with RCAS-SCCRO and RCAS-PDGF-β show a distinct immunohistochemical profile with increased MIB1 expression and vimentin expression relative to those infected with RCAS-PDGF-β alone. Loss of S100 expression was seen in RCAS-SCCRO- and RCAS-PDGF-β-induced gliomas.