Furthermore, several PD-associated genes, such as SNCA (encoding α-synuclein, which forms the Lewy body aggregates found in PD), PINK1 and PARK7 (encoding PTEN-induced kinase 1 and DJ-1, respectively, both of which protect neurons from oxidative stress), and PARKIN (encoding a ubiquitin ligase), exhibit dual roles in cancer (Li et al., 2016). This evidence concerns the gene SNCA and Parkinson disease.