Purpose: To elucidate the role of D-type cyclins in both superficial (Ta-T1) and muscle-invasive (T2-T4) urothelial carcinomas (UCs), investigating their potential prognostic usefulness.
Methods: Paraffin-embedded tissues from 157 patients with bladder UC were immunostained for cyclins D1, D2 and D3.
Results: Cyclin D1 expression positively correlated with D2 and negatively with D3. Cyclin D1 expression decreased with increasing grade (P = 0.0001) and tumour T-category in the entire cohort and in muscle-invasive carcinomas (P = 0.0001 and P = 0.0033). Cyclin D2 correlated with grade (P = 0.0005) and T-category (P = 0.0078), a relationship which remained significant in muscle-invasive (P = 0.0135). Cyclin D3 immunoreactivity increased with histologic grade and T-category in the entire cohort (P = 0.0001 in both relationships), in superficial (P = 0.0034) and in muscle-invasive carcinomas (P = 0.0036, respectively). Survival analysis in superficial tumours showed that higher cyclin D1 (P = 0.0001) and higher cyclin D3 levels (P = 0.0032) were correlated with a lesser probability of survival. In muscle-invasive tumours, lower cyclin D1 (P = 0.0234), and D2 (P = 0.0424) and higher cyclin D3 (P = 0.0322) correlated with shortened survival. In multivariate analysis in superficial tumours only cyclin D3 expression remained significant. Cyclin D3 expression also retained its adverse significance in muscle-invasive tumours.
Conclusions: Cyclin D1 overexpression seems to be more important during early T-categories of bladder carcinogenesis, whereas cyclin D3 is implicated in the acquisition of a more aggressive phenotype. Cyclin D3 overexpression emerges as an independent adverse prognostic marker in both superficial and muscle-invasive tumours. Cyclin D1 is an independent indicator of shortened survival only in muscle-invasive tumours.