The Prognostic Value of G1 Cyclins, p21 and Rb Protein in Patients With Colon Cancer

Background/Aim: Cyclins D1 and. play different roles in the cell cycle. Cyclin. promotes chromosome instability, whereas cyclin D1 regulates apoptosis of cells. This study evaluated the prognostic significance of G1 cyclins, p21 and pRb in tumor proliferation. Patients and Methods: A total of 102 patients with colon cancer were operated on and staged according to TNM. Follow-up was 2 to 68 months (mean 38.3 +/- 16.7 months). Expression of cyclin. and D1 were evaluated using immunohistochemistry. Results: Levels of cyclin. expression were correlated with cyclin D1 expression (p=0.038), p21 expression (p=0.047), and pRb expression (p=0.004). The 5-year survival rate along with prognosis of patients with advanced stage (III, IV) colon cancer and cyclin D1 positive tumors, were significantly worse (p=0.009). Statistically significant association was observed between tumor proliferative capacity Ki-67, cyclin D1 (p=0.009), pRb (p=0.031) and p21 (p=0.050). Conclusion: Cyclin D1 is highly expressed in advanced stage colon cancer patients, implying a potential prognostic value.