Method for determining BRAF mutation and wild type BRAF protein by mass spectrometry

摘要

The present invention discloses a method for determining the molar ratio of wild-type (WT) BRAF protein to its protein variant in a biological sample, which comprises the following steps. a) Digesting the sample by using a serine proteinase that specifically cleaves a C-terminal peptide bond to a glutamic acid residue, or a C-terminal peptide bond to a glutamic acid or aspartic acid residue, and digests the peptide with a proteinase. Obtaining a composition comprising the resulting peptide fragment, wherein the mass of the fragment differs between the wild type (WT) B-raf protein and one of the BRAF protein variants. b) Using mass spectrometric techniques, the molar amounts of peptide fragments resulting from the digestion of wild-type (WT) B-raf protein and the digestion of mutants of wild-type (WT) B-raf protein. Quantitatively assaying the peptide fragments for molar amounts. And c) calculating at least one specific ratio between the WT BRAF protein and the variant thereof based on a quantitative assessment. Further, a method for estimating a subject's susceptibility to a given drug treatment for a BRAF-related disease. Additionally, a method of treatment for a subject having a BRAF-related disease. [Selection diagram] Figure 1