Genetic alterations in the K-Ras gene influence the prognosis in patients with cervical cancer treated by radiotherapy.

INTRODUCTION

A high incidence of K-Ras mutations has been identified in a variety of human cancers, especially in codon 12, 13, and 61. Nevertheless, the presence of K-Ras mutations in cervical cancer remains controversial. The aim of this study was to investigate possible mutations in exon 1 and 2 of the K-Ras gene and to assess whether K-Ras mutation status had prognostic and predictive significance and were linked to clinicopathological parameters.

METHODS

Genomic DNA from 107 patients with cervical cancer, treated with radiochemotherapy, were examined for mutations in the coding exons 1 and 2, including exon/intron borders of the K-Ras gene using single-stranded conformation polymorphism and sequence analyses.

RESULTS

K-Ras mutations were detected in 11 patients (10%). Seven tumors showed a mutation in codon 59, 3 tumors in codon 38, and 1 tumor in codon 13. In 6 of the cases with a mutation in codon 59, an additional alteration located in codon 65 was found.Patients with K-Ras mutations had significantly worse recurrence-free survival (P = 0.03), and an association between K-Ras status and distant metastases was also seen (P = 0.04).

CONCLUSIONS

The present data indicate that K-Ras mutations are relatively uncommon in cervical cancer but associates with poorer prognosis, especially in the subset of squamous cell carcinomas. There is a need for new markers in cervical cancer to improve individual treatment, but whether K-Ras mutation status is a potential biomarker in this situation needs further investigations in larger tumor series and in more regions of the K-Ras gene.