title: Expression analysis of Ubc9, the single small ubiquitin-like modifier (SUMO) E2 conjugating enzyme, in normal and malignant tissues.
abstract: Unlike ubiquitination, which targets proteins for degradation, sumoylation modulates protein-protein interactions of target proteins. Although there are multiple E2 enzymes required for ubiquitination, there is only one E2-conjugating enzyme for sumoylation, which is Ubc9. In line with increasing evidence that sumoylation plays an important role in tumorigenesis, we recently demonstrated that Ubc9 is expressed at high levels in advanced melanomas and that blocking expression of Ubc9 sensitizes melanomas to the cytotoxic effects of chemotherapeutic drugs. To determine whether and to what extent Ubc9 is expressed in other malignancies and their normal tissue counterparts, we undertook a detailed analysis of colon, lung, prostate, and breast cancer tissue microarrays. The findings, presented here, document that in primary colon and prostate cancer, Ubc9 expression is increased compared with their normal tissue counterparts, whereas in metastatic breast, prostate, and lung cancer, it is decreased in comparison with their corresponding normal and primary adenocarcinoma tissues. We also provide evidence that Ubc9 expression correlates positively with Dukes' stage and negatively with the Gleason score as well as breast cancer grade and that Ubc9 expression is substantially higher in the luminal than in the nonluminal type of breast cancer.
authors.affiliation: Department of Medicine, University of Pittsburgh, Pittsburgh, PA 15213, USA. moschossj@upmc.edu
authors.forename: Stergios J
authors.initials: SJ
authors.lastname: Moschos
authors.forename: Drazen M
authors.initials: DM
authors.lastname: Jukic
authors.forename: Charalambos
authors.initials: C
authors.lastname: Athanassiou
authors.forename: Rohit
authors.initials: R
authors.lastname: Bhargava
authors.forename: Sanja
authors.initials: S
authors.lastname: Dacic
authors.forename: Xiaolei
authors.initials: X
authors.lastname: Wang
authors.forename: Shih-Fan
authors.initials: SF
authors.lastname: Kuan
authors.forename: Shelley L
authors.initials: SL
authors.lastname: Fayewicz
authors.forename: Csaba
authors.initials: C
authors.lastname: Galambos
authors.forename: Marie
authors.initials: M
authors.lastname: Acquafondata
authors.forename: Rajiv
authors.initials: R
authors.lastname: Dhir
authors.forename: Dorothea
authors.initials: D
authors.lastname: Becker
mesh_terms: D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D009362:Neoplasm Metastasis / Q000473:pathology; D009369:Neoplasms / Q000201:enzymology* / Q000473:pathology; D046888:Tissue Array Analysis; D044763:Ubiquitin-Conjugating Enzymes / Q000378:metabolism*; D000098843:Ubiquitin-Conjugating Enzyme UBC9
chemical_list: D044763:Ubiquitin-Conjugating Enzymes; D000098843:Ubiquitin-Conjugating Enzyme UBC9