A synthetic, 20-base antisense oligodeoxynucleotide that hybridizes to c-raf kinase messenger RNA. ISIS 5132 has been shown to specifically suppress Raf-1 expression both in vitro and in vivo. Raf-1 serine/threonine kinase functions as a critical effector of Ras-mediated signal transduction; constitutive activation of this pathway directly contributes to malignant transformation. or A substance that is being studied in the treatment of cancer.