Immunohistochemical analysis of SCA has demonstrated that lower expression of some proteins implicated in tumor progression and metastasis, such as galectin-3, a beta-galactoside-binding protein, and KLK10, belonging to the kallikrein family, in SCA than functioning ACTHomas may be one mechanism of its aggressiveness (30). This evidence concerns the gene KLK4 and autosomal dominant cerebellar ataxia.