Detection of oncogenic mutations in cervical carcinoma using method High Resolution Melting (HRM)

Oncogenic mutations in proto-oncogenes and tumor suppressor genes represent one of key events in cancerogenesis. In this study, we analysed mutation status in PIK3CA, KRAS and EGFR proto-oncogenes and TP53 tumor suppressor gene in a cohort of twenty-four patients diagnosed with squamous cell carcinoma or adenocarcinoma using the screening method "High Resolution Melting" (HRM). Positive findings were confirmed and identified by Sanger sequencing. Totally, we detected DNA sequence changes in targeted regions in seven patients (7/24, 29.2%). In PIK3CA gene, we found six sequence changes in four patients (4/24, 16.7%) and four of them were confirmed as oncogenic mutations. In KRAS gene, we detected sequence changes in four patients (4/24, 16.7%). Conversely, we identified pathogenic or potentially pathogenic sequence changes neither in EGFR nor TP53 genes. Our results suggest that sequence changes are specific neither for a certain histological subtype, clinical stage nor lymph node involvement and they appear independently on the presence of HPV (human papillomavirus) infection since early clinical stages. We observed the correlation between the presence of DNA sequence changes and hTERC gene amplification, but we did not find a significant relationship between the identified DNA sequence changes and detected copy-number alterations using the technique of array-CGH (array-based comparative genomic hybridization). Regardless our results confirmed an important role of oncogenic mutations in PIK3CA and KRAS genes in the neoplastic transformation process in the cervical carcinoma pathogenesis. Their identification in the early clinical stages should encourage further studies to better understand these mutations and exploit them for more detailed diagnostics.