Roles of cyclin D1 and cyclin E in non-small-cell lung cancer and the relationship between cyclin D1 and cyclin E

Purpose:To study the roles of cyclin D1 and cyclin E in non small cell lung cancer(NSCLC) and the relationship between cyclin D1 and cyclin E.Methods:The expression of cyclin D1 and cyclin E in 87 NSCLC were studied immunohistochemically, PCNA was detected immunohistochemically to estimate the proliferative index(PI), the relationship between cyclin D1, cyclin E, PI, clinicopathological and prognostic factors were analysed.Results:Of the 87 NSCLC, 44 8%(39/87) were positive for cyclin D1 and 48.3%(42/87) for cyclin E, the PI of the cyclin D1 positive group was significantly higher than the cyclin D1 negative group( P 〈0.05).Significant differences were shown in the diameter of tumor, lymph node metastasis rate and survival rate between the positive and negative group of cyclin D1( P 〈0.01,0.05,0.01), and there were significant differences in lymph node metastasis, stages and survival rate between the positive and negative group of cyclin E( P 〈0.05,0.05,0.01). The expression of cyclin E in the cyclin D1 positive group was significantly higher than that of the cyclin D1 negative group( P 〈0.05), and the PI, diameter of tumor, lymph node metastasis rate in the coexpression group of cyclin D1 and cyclin E were significantly higher than that of the non coexpression group( P 〈0.05), while the coexpression group had significantly lower survival rate than that of the non coexpression group( P 〈0.05).Conclusions:Cyclin D1 and cyclin E are involved in NSCLC, but their effects are different: cyclin D1 is an important factor in the regulation of proliferation, cyclin E is related to the progression of NSCLC, cyclin D1 can promote the expression of cyclin E, while cyclin E can perhaps intensify the effect of cyclin D1, thus there could exist synergism between cyclin D1 and cyclin E.