Interactions between Viscum album (Iscador) and DNA were studied by amplification
of specific human pepsinogen A gene promoter sequences by polymerase chain reaction
(PCR). Gel retardation assays showed no binding of Viscum album to these promoter
sequences. Incubation of plasmid constructs consisting of human pepsigen A promoter
fragments coupled to the chloramphenicol acetyltransferase (CAT) reporter gene with
Iscador had no effect on transcriptional activity. Promoter sequences incubated with
Iscador became insensitive to methylation by specific DNA methyltransferases by destruction
of DNA methyltransferase activity.
Keywords
Carcinogenesis - DNA methylation - Gastric chief cells - Pepsinogen A -
Viscum album L. - Polymerase chain reaction