CR-1-31 B, a synthetic silvestrol analog [27], shows very potent single agent activity against many cancer cell lines in vitro with B cell lymphoma lines among the most sensitive with an area under the CR-1-31 B response curve ranging from 0.5737 (Pfeiffer) to 15 (REC1) (Figure 1A). The gene discussed is RAD1; the disease is B-cell non-Hodgkin lymphoma.