RBL2 and neoplasm: The expression of the cell-cycle promoting cyclins D1 and E, the cell-cycle inhibitors Rb, Rb2, p16, p21 and p27, and the proliferation marker Ki67 had been studied before by Western blot analysis or, for Ki67, by immunohistochemistry in 75 tumours from our cohort (Milde-Langosch et al, 2000).