| abstract |
In particular aspects, stem-cell polycomb group (PcG) targets are more likely to have cancer-specific promoter DNA methylation than non-targets, indicating a stem-cell origin of cancer, where reversible gene repression is replaced by permanent silencing, locking the cell into a perpetual state of self-renewal and predisposition to subsequent malignant transformation. Exemplary aspects provide methods for identifying preferred DNA methylation markers for a cellular proliferative disorder and/or cancer and markers for developmental lineages and/or stages, based on identifying PcG protein or PcG repressive complex genomic target loci within a precursor cell (e.g., stem or progenitor cell) population, and determining, in cells of the proliferative disorder and/or cancer or cell of the particular developmental lineages and/or stages, a characteristic methylation status of the PcG target loci. Additional aspects provide methods for validating and/or monitoring a precursor cell (e.g., stem cell) population. Diagnostic and prognostic methods for ovarian and breast cancer are provided. |