The therapeutic end point of destabilization of abnormal methylation
enzymes is terminally differentiated cells. This end point is compatible
with the end point on the therapy of hematological cancers. It can fit
in on the therapy of hematological cancers, but it will not be easy for
the acceptance on the therapy of solid cancers. In combination with
surgery, or cytotoxic chemotherapy to pursue the end point of tumor
disappearance is perhaps an easy way out. Different end points, however,
have to be sought to legitimate differentiation therapy. End point of
the disappearance of circulating cancer stem cells, or restoration of
plasma/urine peptide ratios to those of healthy people are valid, but
need careful studies before being accepted as valid end points.