Basal acetylation of histone H3 and H4 was higher in ovarian carcinoma compared to normal ovarian tissues and benign ovarian tumors, and in borderline tumor than in normal ovarian tissues, and was positively correlated with differentiation and expression of the proliferative marker, Ki-67 (P < 0.05). This evidence concerns the gene MKI67 and ovarian benign neoplasm.