SummaryThe expression of cyclin D1 protein in tumour sections from 81 patients with epithelial ovarian cancer was analysed using immunohistochemistry. The tumours that overexpressed cyclin D1 in more than 10% of neoplastic cells were considered positive. Thus overexpression of cyclin D1 was observed in 72/81 (89%) of the cases examined. Protein was detected in both the nucleus and the cytoplasm in 24/81 (30%) and localized exclusively in the cytoplasm in 48/81 (59%) of the tumours. Cyclin D1 was overexpressed in both borderline and invasive tumours. There was no association between protein overexpression and tumour stage and differentiation. Furthermore, no correlation between cyclin D1 expression and clinical outcome was observed. However, in tumours overexpressing cyclin D1 (n = 72), the proportion displaying exclusively cytoplasmic localization of protein was higher in those with serous compared with non-serous histology (P = 0.004, odds ratio 4.8, 95% confidence interval 1.4-19.1). Western analysis using a monoclonal antibody to cyclin D1 identified a 36 kDa protein in homogenates from seven tumours displaying cytoplasmic only and one tumour demonstrating both nuclear and cytoplasmic immunostaining. Using restriction fragment length polymorphism polymerase chain reaction and PCR-multiplex analysis, amplification of the cyclin D1 gene (CCNDI) was detected in 1/29 of the tumours demonstrating overexpression of cyclin D1 protein. We conclude that deregulation of CCND1 expression leading to both cytoplasmic and nuclear protein localization is a frequent event in ovarian cancer and occurs mainly in the absence of gene amplification.

We have investigated the influence of CCND1 genotype on clinical outcome in 138 women with epithelial ovarian cancer. CCND1 genotypes were identified from peripheral blood DNA by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) analysis. Patient CCND1 genotypes were compared with clinical details including FIGO tumor stage, residual tumor volume, tumor histology and differentiation, response to chemotherapy, progression free interval, and survival. We observed no association between patient CCND1 genotypes and tumor characteristics or response to chemotherapy. There was no significant difference in overall survival and progression free interval (PFI) among women with different CCND1 genotypes. However, analysis of data from patients who responded to postoperative chemotherapy revealed that women with CCND1 AA genotype were associated with early disease progression (P = 0.020, HR 4.58, 95% CI 1.27-16.48) and reduced survival (P = 0.026, HR 4.48, 95% CI 1.19-16.79) compared with those with CCND1 AG and GG genotypes. These data show that CCND1 genotype does not influence overall prognosis in a cohort of epithelial ovarian cancer patients, however, it is associated with disease progression in a subgroup of patients following initial response to chemotherapy.