학술논문

Direct inhibition of oncogenic KRAS by hydrocarbon-stapled SOS1 helices.
Document Type
Article
Source
Proceedings of the National Academy of Sciences of the United States of America. 2/10/2015, Vol. 112 Issue 6, p1761-1766. 6p.
Subject
*CANCER cells
*DROSOPHILA
*CARCINOGENESIS
*PEPTIDES
*CELL-mediated cytotoxicity
Language
ISSN
0027-8424
Abstract
Activating mutations in the Kirsten rat sarcoma viral oncogene homolog (KRAS) underlie the pathogenesis and chemoresistance of ~30% of all human tumors, yet the development of high-affinity inhibitors that target the broad range of KRAS mutants remains a formidable challenge. Here, we report the development and validation of stabilized alpha helices of son of sevenless 1 (SAH-SOS1) as prototype therapeutics that directly inhibit wild-type and mutant forms of KRAS. SAH-SOS1 peptides bound in a sequence- specific manner to KRAS and its mutants, and dose-responsively blocked nucleotide association. Importantly, this functional binding activity correlated with SAH-SOS1 cytotoxicity in cancer cells expressing wild-type or mutant forms of KRAS. The mechanism of action of SAH-SOS1 peptides was demonstrated by sequence-specific down-regulation of the ERK-MAP kinase phosphosignaling cascade in KRAS-driven cancer cells and in a Drosophila melanogaster model of Ras85DV12 activation. These studies provide evidence for the potential utility of SAH-SOS1 peptides in neutralizing oncogenic KRAS in human cancer. [ABSTRACT FROM AUTHOR]