For example Spirotryptostatin A and B,1 and 2 inhibits tubulin polymerization and induces cell cycle inhibition of cancer cells at G2/M phase and spirooxindole MI-5, 3, demonstrated novel type of inhibition of p53-MDM2 protein-protein interaction that is critical for modulating tumor suppressing ability of the p53-proteins (Fig. 1)12, 13, 14. Here, TP53 is linked to cancer.