3% of patients eligible for a therapy with vemurafenib. The pyrosequencing approach selleck chem Vorinostat showed in fact the highest sensitivity in our preselected cohort with a limit of detection of 5% mutant alleles but exhibited the lowest specificity with 90% and is prone to errors without using customer designed set up. In their present set up, the cobas 4800 BRAF V600 test as well as the therascreen BRAF Pyro Kit are therefore not sufficient for the European approval of vemurafenib because there is a therapeutic option for melanoma patients with any mutation in codon 600 of the BRAF gene. Therefore, we suggest a com bination of VE1 antibody staining and HRM for p. V600E mutation analysis combining the lowest detection limit with a fast, reliable method with 100% sensitivity for rou tine diagnostics at the moment.
In the near future and with growing experiences, it is an inevitable fact that NGS will replace all established methods for molecular diagnostics. This is based on the high sensitivity and multiplexing options of this method allowing to generate a molecular profile of each tumor sample analyzed. Background The v raf murine sarcoma Inhibitors,Modulators,Libraries viral oncogene homolog B1 is one of three RAF genes localized on chromosome 7q34. This gene encodes a cytoplasmic serine threonine pro tein kinase of the RAF family. RAF kinases are part of the mitogen activated protein kinase pathway in volved in cell growth, survival and differentiation. Inhibitors,Modulators,Libraries BRAF mutations play an important role in 40 70% of malignant melanomas, 45% of papillary thyroid cancers and 10% of colorectal cancers besides ovarian, breast and lung cancers.
According to the COSMIC Inhibitors,Modulators,Libraries database 44% of the melanomas harbor BRAF mutations and 97. 1% of these mutations are localized in codon 600 of the BRAF gene. The most common variation is a substitution of valine to glutamic acid at codon 600. Less common mutations are substitutions of valine to lysine, to arginine, to leu cin or to aspartic acid, mutations affect ing codon 597, codon 594 and mutations in codon 601 resulting in the exchange of lysine to glutamic acid. The approval of vemurafenib in the US 2011 and in Europe 2012 improved the therapy of not resectable or metastatic melanoma. Vemurafenib exhibits an approxi mately 30 fold selectivity for p. V600E mutated compared to wildtype BRAF melanomas. In addition, patients car rying a p.
V600K mutation included in the BRIM 3 study showed response to this inhibitor. In a phase I trial, a 70% response rate to vemurafenib among 32 genotype selected metastatic melanoma patients was observed. Recent in vitro and in Inhibitors,Modulators,Libraries vivo experiments indicate that vemurafenib might have an effect in patients with rare mutations in codon 600 of the BRAF gene as for instance p. V600D or p. V600R. Furthermore, dab rafenib, another selective BRAF inhibitor shows good clinical Inhibitors,Modulators,Libraries response rates not only for patients with p. V600E or selleckchem p. V600K mutations but also in patients carrying a p. V600R, p. V600M or a double p.