Cyclin E low molecular weight isoforms occur commonly in early-onset gastric cancer and independently predict survival.

Department of Pathology, University Medical Centre, Utrecht, The Netherlands.
Journal of clinical pathology (Impact Factor: 2.43). 04/2008; 61(3):311-6. DOI: 10.1136/jcp.2006.042648
Source: PubMed

ABSTRACT Post-translational cleavage of full-length cyclin E from the N-terminus can produce low molecular weight (LMW) isoforms of cyclin E containing the C-terminus only.
To assess their presence in early-onset gastric cancer (EOGC), stump cancers and conventional gastric cancers and ascertain how they influence survival in EOGC.
The expression of full-length and LMW isoforms of cyclin E in 330 gastric cancers, including early-onset gastric cancer (EOGC), stump cancer and conventional gastric cancer (>45 years old) was compared using antibodies targeted to the N- and C-terminals.
LMW isoforms were found in 35% of EOGCs, compared to 8% of conventional gastric cancers and 4% of stump cancers; their presence was visualised in cell lines using western blot analysis. In addition, C-terminal staining was a positive predictor of survival in EOGC. In contrast, no correlation with survival was found with the N-terminal antibody which detects only full-length cyclin E.
EOGCs have a unique molecular phenotype and LMW isoforms of cyclin E may independently influence survival in EOGC.

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