title: SUMOylation proteins in breast cancer.
abstract: Small Ubiquitin-like Modifier proteins (or SUMO) modify the function of protein substrates involved in various cellular processes including DNA damage response (DDR). It is becoming apparent that dysregulated SUMO contribute to carcinogenesis by affecting post-transcriptional modification of key proteins. It is hypothesised that SUMO contributes to the aggressive nature of breast cancer particularly those associated with features similar to breast carcinoma arising in patients with BRCA1 germline mutations. This study aims to assess the clinical and biological significance of three members of SUMO in a well-characterised annotated series of BC with emphasis on DDR. The study cohort comprised primary operable invasive BC including tumours from patients with known BRCA1 germline mutations. SUMO proteins PIAS1, PIAS4 and UBC9 were assessed using immunohistochemistry utilising tissue microarray technology. Additionally, their expression was assessed using reverse phase protein microarray utilising different cell lines. PIAS1 and UBC9 showed cytoplasmic and/or nuclear expression while PIAS4 was detected only in the nuclei. There was a correlation between subcellular localisation and expression of the nuclear transport protein KPNA2. Tumours showing positive nuclear/negative cytoplasmic expression of SUMO featured good prognostic characteristics including lower histologic grade and had a good outcome. Strong correlation with DDR-related proteins including BRCA1, Rad51, ATM, CHK1, DNA-PK and KU70/KU80 was observed. Correlation with ER and BRCA1 was confirmed using RPPA on cell lines. SUMO proteins seem to play important role in BC. Not only expression but also subcellular location is associated with BC phenotype.
authors.affiliation: Department of Histopathology and School of Molecular Medical Sciences, The University of Nottingham and Nottingham University Hospitals NHS Trust, Nottingham City Hospital, Nottingham, UK, mrxaa31@nottingham.ac.uk.
authors.forename: Alaa T
authors.initials: AT
authors.lastname: Alshareeda
authors.forename: Ola H
authors.initials: OH
authors.lastname: Negm
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Green
authors.forename: Christopher
authors.initials: C
authors.lastname: Nolan
authors.forename: Paddy
authors.initials: P
authors.lastname: Tighe
authors.forename: Nada
authors.initials: N
authors.lastname: Albarakati
authors.forename: Rebeka
authors.initials: R
authors.lastname: Sultana
authors.forename: Srinivasan
authors.initials: S
authors.lastname: Madhusudan
authors.forename: Ian O
authors.initials: IO
authors.lastname: Ellis
authors.forename: Emad A
authors.initials: EA
authors.lastname: Rakha
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers; D001943:Breast Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D045744:Cell Line, Tumor; D015331:Cohort Studies; D004260:DNA Repair; D005260:Female; D015870:Gene Expression; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D060787:Neoplasm Grading; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D063868:Patient Outcome Assessment; D011379:Prognosis; D025841:Small Ubiquitin-Related Modifier Proteins / Q000378:metabolism*; D058207:Sumoylation; D047368:Tumor Burden
chemical_list: D015415:Biomarkers; D025841:Small Ubiquitin-Related Modifier Proteins