PFDN5 and Huntington disease: Other potentially common factors in cancer and neurodegenerative diseases include the PARK7 (DJ-1) and APP oncogenes (the first is involved in mitochondrial regulation, the second is a precursor of the β-amyloid protein), the PFDN5 (MM-1) and PRKN (Parkin) tumor suppressors (the first inhibits transcription and protein aggregation, involved in the onset of PD, cerebellar atrophy and HD, the latter plays a role in mitophagy and ubiquitination), and the PDAP1 (PAP1) and PINK1 modulators (the former is involved in splicing and the latter in mitophagy) [44].