In vitro interaction of serum protein with circulating DNA of lung cancer patient.

Circulating DNA and oncoproteins can be extracted from serum or plasma of cancer patients. In this study, using gel retardation analysis we observed circulating DNA obtained from plasma of a lung cancer patient complexed with serum proteins. p53 was identified by immunoblotting as one of the proteins present in the complex. Our finding suggests that the same interaction observed between p53 and DNA in intact cells occurs in serum of lung cancer patient. As far as we know this is the first evidence for such finding.