G870A Polymorphic Variants of CCND1 Gene and Cyclin D1 Protein Expression as Prognostic Markers in Laryngeal Lesions

CCND1 gene encodes Cyclin D1 protein, the alternations and overexpression of which are commonly observed in human cancers. Cyclin D1 controls G1-S transition in the cell cycle. The aim of the study was to assess utility of the genotyping and protein expression in predicting the susceptibility of transformation from normal tissue to precancerous laryngeal lesions (PLLs) and finally to laryngeal cancer (LC). Four hundred and thirty-five patients (101 with LC, 100 with PLLs and 234 healthy volunteers) were enrolled in the study. Cyclin D1 expression was examined by immunohistochemistry and G870A polymorphism of gene CCND1 by PCR-RFLP technique. We confirmed association between the A allele and risk of developing LC from healthy mucosa (p = 0.006). Significantly higher expression of Cyclin D1 was observed in LC compering with PLLs (p < 0.0001) and we found that it could be a predictive marker of shorter survival time. To sum up, in the study population CCND1 gene polymorphism A870G and Cyclin D1 expression have a significant impact on the risk of developing PLLs and LC, and, therefore, Cyclin D1 could be a useful marker for the prediction of survival time in LC, whereas CCND1 gene polymorphism does not have a direct impact on patients’ outcome.