DNA adducts in squamous cell cervical carcinomas associated with HPV infection

The aim of the study was qualitative and quantitative evaluation of DNA adducts in squamous cell cervical carcinomas associated with oncogenic HPV infection.

Material: The study material consisted of oncogenic tissue collected during the surgeries of seven women aged 37 to 52 who were undergoing surgical treatment due to squamous cell cervical carcinoma. The control group consisted of 3 tissue fragments from morphologically normal cervix collected from patients undergoing surgery due to uterine myomas.

Methods: DNA from the tissues was isolated using Genomic Prep Plus kit from A&A Biotechnology, Austria. Amplification reactions detecting HPV DNA presence in the tissue fragments were performed using specific starters allowing for amplification of conservative genome fragments within L1, E6 and E7 Papilloma viruses. After extraction, the DNA specimens underwent enzymatic digestion to nucleotides and marked on the 5' end using gamma32P-post labeling technique. Division and quantitative evaluation of DNA adducts was performed using thin-layer chromatography (TLC) on PEI-cellulose plates. Qualitative radioactivity measurements were performed using Bio-Imaging analyzer in quantitative mode.

Results: In all fragments, including the control, HPV 16 and/or 18 DNA was found. Mean adduct content in cervical carcinoma tissues was 289 adducts per 10(9) nucleotides and was higher than mean adduct content in control tissues (57 adducts per 10(9) nucleotides).

Conclusions: The study results suggest that the content of DNA adducts in squamous cell cervical cancer associated with HPV infection may serve as a molecular marker of oncogenesis in this organ.

Squamous cervical cancer; HPV 16 and/or 18; Adducts

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