There is a strong genetic influence on the clinicopathological phenotypes associated with frontotemporal lobar degeneration (FTLD) and frontotemporal dementia (FTD). Intracellular deposition of TDP-43 is the phenotypical hallmark of a frequent subgroup of cases. Mutations in the sequestosome 1 (SQSTM1) gene have rarely been found in individuals with FTD. Here we provide a comprehensive clinicopathological description of two cases with a SQSTM1 mutation. The clinical phenotype of patient 1 (mutation p.Glu396*) was compatible with the behavioural variant (bv) of FTD. TDP-43 pathology was consistent with the features of type B of FTLD-TDP pathology. However, prominent neuronal granular cytoplasmic TDP-43 immunoreactivity and abundant oligodendroglial inclusions, proven by colocalization with the oligodendroglial-marker TPPP/p25, were also seen. The clinical phenotype of patient 2 was compatible with bvFTD associated with parkinsonism and bulbar symptoms in the later stage. Genetic testing of patient 2 identified a C9orf72 repeat expansion mutation together with a missense mutation (p.Arg212Cys) in SQSTM1. TDP-43 pathology was characterized by neuritic profiles compatible mostly with type A. In contrast to patient 1, p62 pathology was seen to a greater extent as TDP-43 immunoreactivity in neurons. Using an antibody that detects poly(GP) peptides produced via repeat associated non-ATG translation associated with expanded hexanucleotide repeat in the C9orf72 gene, we confirmed the presence of pathognomonic inclusions. The present study supports previous observations on amyotrophic lateral sclerosis (ALS) that SQSTM1 mutations consistently associate with TDP-43 pathology. The co-presence of C9orf72 mutation may influence the phenotype, thus finding one FTLD (or ALS) related mutation does not exclude the presence of further influential genetic alterations. Oligodendroglial TDP-43 pathology is considerable in some forms of FTLD-TDP, thus their evaluation might be considered to be included in classification systems.

• Klíčová slova
• FTD, SQSTM1, TDP-43, amyotrophic lateral sclerosis, p62,
• MeSH
• adaptorové proteiny signální transdukční genetika   MeSH
• chování MeSH
• dospělí MeSH
• expanze repetic DNA MeSH
• frontotemporální demence genetika   MeSH
• lidé středního věku MeSH
• lidé MeSH
• missense mutace genetika   MeSH
• mutační analýza DNA MeSH
• neurity patologie   MeSH
• neurony patologie   MeSH
• oligodendroglie patologie   MeSH
• progrese nemoci MeSH
• protein C9orf72 MeSH
• proteinopatie TDP-43 genetika   patologie   MeSH
• proteiny genetika   MeSH
• protoonkogenní proteiny c-myc genetika   MeSH
• sekvestosom 1 MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH
• práce podpořená grantem MeSH
• Názvy látek
• adaptorové proteiny signální transdukční MeSH
• C9orf72 protein, human MeSH Prohlížeč
• protein C9orf72 MeSH
• proteiny MeSH
• protoonkogenní proteiny c-myc MeSH
• sekvestosom 1 MeSH
• SQSTM1 protein, human MeSH Prohlížeč