CST3 and amyotrophic lateral sclerosis: Among the significantly dysregulated proteins identified in this study, some of the best characterized biomarker candidates for ALS such as neurofilament heavy and medium polypeptides, cystatin C or SOD1 (one of the best known ALS causing mutations) (Table 2) were found, thus corroborating the excellent quality of our data and supporting the reliability of the new observations here reported.