Neuron-Specific Enolase (NSE) is a biomarker composedof αγ-and γγ-dimers that is used for both diagnosis and follow-upin lung cancer.15 Using bottom-up LC-MSassays, it is already possible to distinguish between these isoforms,as was demonstrated in previous work.4 However,the development of an intact mass proteomics method could lead toa simplified method for isoform differentiation, incorporation ofPTMs in the analysis, and quantification and correction for, e.g.,hemolysis, since erythrocytes contain high concentration of αγ-NSE.16 This evidence concerns the gene RENBP and lung cancer.