Cited by 678Open Access
Memorial Sloan Kettering Cancer Center
Publishes on Cancer-related Molecular Pathways, Protein Kinase Regulation and GTPase Signaling, Microtubule and mitosis dynamics. 21 papers and 3.3k citations.
Add your photo, update your bio, and get notified when your ranking changes.
To identify proteins that may participate in the activation of the protein kinase Raf, proteins that interact with Raf were selected in a two-hybrid screen. Two members of the 14-3-3 protein family were isolated that interacted with both the amino terminal regulatory regions of Raf and the kinase domain of Raf, but did not compete with the guanine nucleotide-binding protein Ras for binding to Raf. 14-3-3 proteins associated with Raf in mammalian cells and accompanied Raf to the membrane in the presence of activated Ras. In yeast cells expressing Raf and MEK, mammalian 14-3-3 beta or 14-3-3 zeta activated Raf to a similar extent as did expression of Ras. Therefore, 14-3-3 proteins may participate in or be required for the regulation of Raf function. These findings suggest a role for 14-3-3 proteins in Raf-mediated signal transduction.
BACKGROUND: We address the prognostic and predictive value of KRAS, PIK3CA and BRAF mutations for clinical outcomes in response to active agents in the treatment of metastatic colorectal cancer (mCRC). METHODS: We determined KRAS, BRAF and PIK3CA mutations in tumours from 168 patients treated for mCRC at two institutions. All patients received 5-FU-based first-line chemotherapy and treatment outcome was analysed retrospectively. RESULTS: KRAS, BRAF and PIK3CA mutations were present in 62 (37%), 13 (8%) and 26 (15%) cases, respectively. Multivariate analysis uncovered BRAF mutation as an independent prognostic factor for decreased survival (hazard ratio (HR) 4.0, 95% confidence interval (CI) 2.1-7.6). In addition, patients with BRAF-mutant tumours had significantly lower progression-free survival (PFS: HR 4.0, 95% CI 2.2-7.4) than those whose tumors that carried wild-type BRAF. Among 92 patients treated using chemotherapy and cetuximab as salvage therapy, KRAS mutation was associated with lack of response (P=0.002) and shorter PFS (P=0.09). BRAF (P=0.0005) and PIK3CA (P=0.01) mutations also predicted reduced PFS in response to cetuximab salvage therapy. CONCLUSIONS: These results underscore the potential of mutational profiling to identify CRCs with different natural histories or treatment responses. The adverse significance of BRAF mutation should inform patient selection and stratification in clinical trials.