Association of HPV16 and 18 genomic copies with histological grades of cervical lesions.

Abstract

The possible correlation between HPV16 and HPV18 genomic copies with the grade of cervical lesions needs more investigations. The aim of this study was to quantify genomic copies of HPV16 and 18 simultaneously and to find out the correlation between genomic copies numbers and different grades of lesions. Therefore, a total of 102 formalin-fixed and paraffin-embedded tissue specimens, 33 LSILI, 43 HSIL, and 26 squamous/adenocarcinoma were subjected to DNA extraction. The β-globin gene was selected to qualify the extracted DNA as well as normalization of viral titers using Taq-Man real-time PCR. The presence HPV16 and/or 18 were screened in tissue samples by nested PCR method, then an in- house Taq-Man Duplex real-time PCR assay was employed to quantify their genomic copies. The mean age of participants was 43 ± 13. Out of 102, 80 samples were positive for HPV16 and/or 18 DNA. There was a statistically significant association between HPV16 genomic copies and progression of cervical lesions (P < 0.001). In contrast, no such an association was found in the case of HPV18 (P = 0.51). Moreover, with 95% confidence intervals, 2.3-4 genomic copies of HPV16 genome/cell could be applicable to distinguish LSIL from HSIL and SCC. In conclusion, quantification of HPV16 genomic copy number showed a close association with progression of cervical lesion. Furthermore, HPV16 genomic copies of 4 copies/cell could be a set point to differentiate LSIL from HSIL.