Diagnosis of 25 genotypes of human papillomaviruses for their physical statuses in cervical precancerous/cancerous lesions: a comparison of E2/E6E7 ratio-based vs. multiple E1-L1/E6E7 ratio-based detection techniques

Abstract

BackgroundCervical lesions caused by integrated human papillomavirus (HPV) infection are highly dangerous because they can quickly develop into invasive cancers. However, clinicians are currently hampered by the lack of a quick, convenient and precise technique to detect integrated/mixed infections of various genotypes of HPVs in the cervix. This study aimed to develop a practical tool to determine the physical status of different HPVs and evaluate its clinical significance.MethodsThe target population comprised 1162 women with an HPV infection history of > six months and an abnormal cervical cytological finding. The multiple E1-L1/E6E7 ratio analysis, a novel technique, was developed based on determining the ratios of E1/E6E7, E2/E6E7, E4E5/E6E7, L2/E6E7 and L1/E6E7 within the viral genome. Any imbalanced ratios indicate integration. Its diagnostic and predictive performances were compared with those of E2/E6E7 ratio analysis. The detection accuracy of both techniques was evaluated using the gold-standard technique “detection of integrated papillomavirus sequences” (DIPS). To realize a multigenotypic detection goal, a primer and probe library was established.ResultsThe integration rate of a particular genotype of HPV was correlated with its tumorigenic potential and women with higher lesion grades often carried lower viral loads. The E1-L1/E6E7 ratio analysis achieved 92.7% sensitivity and 99.0% specificity in detecting HPV integration, while the E2/E6E7 ratio analysis showed a much lower sensitivity (75.6%) and a similar specificity (99.3%). Interference due to episomal copies was observed in both techniques, leading to false-negative results. However, some positive results of E1-L1/E6E7 ratio analysis were missed by DIPS due to its stochastic detection nature. The E1-L1/E6E7 ratio analysis is more efficient than E2/E6E7 ratio analysis and DIPS in predicting precancerous/cancerous lesions, in which both positive predictive values (36.7%-82.3%) and negative predictive values (75.9%-100%) were highest (based on the results of three rounds of biopsies).ConclusionsThe multiple E1-L1/E6E7 ratio analysis is more sensitive and predictive than E2/E6E7 ratio analysis as a triage test for detecting HPV integration. It can effectively narrow the range of candidates for colposcopic examination and cervical biopsy, thereby lowering the expense of cervical cancer prevention.Electronic supplementary materialThe online version of this article (doi:10.1186/s12967-014-0282-2) contains supplementary material, which is available to authorized users.

Human papilloma virus and breast cancer: the role of inflammation and viral expressed proteins

“…This issue has already been proven in Cervical Cancer [40]. One of the limitations in our study was to use E2 / E6 ratio for determination of physical status of HPV genome while Zhang et al have demonstrated that E2/E6 or E2/E7 is less sensitive and predictive than E2/E6E7 for determination of physical status of HPV genome in cervical cancer [54]. Therefore, in our study, the percentage of integrated HPV genomes was probably more than the percentage we reported.…”

Detection and genotyping of human papillomavirus (HPV) in HIV-infected women and its relationship with HPV/HIV co-infection

“…[ 36 ] Some experts have hypothesized that HPV16 has better evolutionary ability to escape the effects of immune surveillance, while non-HPV16 genotypes are often better controlled by the immune response. [ 36 , 37 ] Consequently, in women with progressive weakening of the immune system, the immune control over non-HPV16 types may be lost, promoting the rise in the prevalence of types frequently targeted by a competent immune system. [ 37 ]…”

“…[ 36 , 37 ] Consequently, in women with progressive weakening of the immune system, the immune control over non-HPV16 types may be lost, promoting the rise in the prevalence of types frequently targeted by a competent immune system. [ 37 ]…”

Elevated HPV16 E1 Expression Is Associated with Cervical Cancer Progression

“…However, it has been demonstrated in numerous studies that HPV16 shows a different integration pattern in conjunction with disease. Zhang et al [33] found a 27.7% integration rate of HPV16 in precancerous lesions. This study detected a high number of samples with fully integrated HPV16 in normal samples (2/6, 33%), similar to a finding reported by Dutta et al [34] (27% integration in normal samples).…”