The specificity of the thalidomide effect is further underscored by our observation that PMA (phorbol myristate acetate, or 12-0-tetradecanoyl-phorbol-13-acetate) (10 nM) a tumor-promoting ester treatment attenuated CUL5 but not NEDD8 signal intensity (Fig 5A, bottom panel). The gene discussed is NEDD8; the disease is neoplasm.