| First Author | Kwong LN | Year | 2012 |
| Journal | Nat Med | Volume | 18 |
| Issue | 10 | Pages | 1503-10 |
| PubMed ID | 22983396 | Mgi Jnum | J:238049 |
| Mgi Id | MGI:5818006 | Doi | 10.1038/nm.2941 |
| Citation | Kwong LN, et al. (2012) Oncogenic NRAS signaling differentially regulates survival and proliferation in melanoma. Nat Med 18(10):1503-10 |
| abstractText | The discovery of potent inhibitors of the BRAF proto-oncogene has revolutionized therapy for melanoma harboring mutations in BRAF, yet NRAS-mutant melanoma remains without an effective therapy. Because direct pharmacological inhibition of the RAS proto-oncogene has thus far been unsuccessful, we explored systems biology approaches to identify synergistic drug combination(s) that can mimic RAS inhibition. Here, leveraging an inducible mouse model of NRAS-mutant melanoma, we show that pharmacological inhibition of mitogen-activated protein kinase kinase (MEK) activates apoptosis but not cell-cycle arrest, which is in contrast to complete genetic neuroblastoma RAS homolog (NRAS) extinction, which triggers both of these effects. Network modeling pinpointed cyclin-dependent kinase 4 (CDK4) as a key driver of this differential phenotype. Accordingly, combined pharmacological inhibition of MEK and CDK4 in vivo led to substantial synergy in therapeutic efficacy. We suggest a gradient model of oncogenic NRAS signaling in which the output is gated, resulting in the decoupling of discrete downstream biological phenotypes as a result of incomplete inhibition. Such a gated signaling model offers a new framework to identify nonobvious coextinction target(s) for combined pharmacological inhibition in NRAS-mutant melanomas. |
