DNA demethylation is directly related to tumour progression: evidence in normal, pre-malignant and malignant cells from uterine cervix samples.

A computer-assisted assay based on the quantitative analysis of DNA methylation in individual interphase nuclei by indirect immunolabelling with anti-5-methylcytosine antibodies was recently developed in our laboratory. In situ analyses were performed on individual nuclei from normal and experimentally hypo- or hypermethylated cultured cells as well as on human peripheral blood B-lymphocytes from normal and chronic lymphoid leukemia (CLL) samples. We present the results obtained on cells from patients affected by different degrees of preneoplastic or neoplastic changes of the uterine cervix as compared to normal controls.