The plant product Bouvardin (BVD; NSC 259968) exhibited high activity against P388 murine leukemia and B16 melanoma, but it was not effect against various other tumor models. BVD inhibited the synthesis of all the macromolecules, namely protein, DNA and RNA, in P388 cells in vitro. Protein synthesis
KB (Eagle) cell culture has played a powerful role in discovery of antitumor agents from higher plants. Had KB alone been used as a preliminary screen, with in vivo screening limited to KB-active extracts, fractions, or compounds, KB activity of crude products would have led to discovery of