EXPERIMENTAL CHEMOTHERAPY STUDIES. 3. PROPERTIES OF DNA FROM ASCITES CELLS TREATED IN VIVO WITH NITROGEN MUSTARD.

Abstract

Summary To obtain information concerning the extent and nature of the chemical attack by HN2 on DNA during the course of chemotherapy, mice bearing Lettre-Ehrlich ascites tumors were given doses of HN2-C 14 which produce significant carcinostasis. After isolation and purification DNA was shown to be alkylated to the extent of 1 in every 10 4 deoxynucleotides. Measurements of the melting behavior, optical characteristics, viscosity, and sedimentation characteristics of this DNA showed no significant differences from those in control, untreated specimens, thus eliminating intermolecular cross-linking or chain scission, exhaustive deguanylation, or changes in base composition as major chemical results of alkylation. The one important gross difference between alkylated and control DNA9s was the retention by the former of increased amounts of protein which cannot be separated by the normal purification procedure.