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Molecular detection of HPV DNA is considered as the gold standard for the diagnosis of cervical disease. Although the molecular assays for the identification of HPV16 and HPV18 have helped identify cervical cancer incidents, they are restricted to specialized laboratories. Thus, we developed a novel 2-stage, nested-like nucleic acid amplification method, named IsoPCR, to amplify the E6 gene of HPV16 and HPV18 with high analytical sensitivity and specificity. The performance of IsoPCR was compared to that of conventional PCR and LAMP. The analytical sensitivity of IsoPCR (1 copy/test) was 10-fold higher than conventional PCR and 25-fold higher than conventional LAMP. IsoPCR displayed significant amplification specificity (100%) and efficiency, as well. In conclusion, IsoPCR is a highly sensitive and specific diagnostic tool and it is suitable for the detection of low copy number of viral DNA in clinical specimens, providing critical information to healthcare providers. • The IsoPCR assay was developed for the detection of HPV16, HPV18 DNA. • The IsoPCR amplify the E6 gene of HPV16 and HPV18 DNA. • The assay enables the amplification of 1 copy/reaction of both HPV16, HPV18 DNA. • The assay exhibits 100% specificity for the detection of HPV16, HPV18 in clinical samples. [ABSTRACT FROM AUTHOR]

Objective HPV genotype distribution varies by race/ethnicity, but is unclear whether there are racial/ethnic variations in HPV 16/18 integration in the host genome. We describe HPV16/18 infection and integration status in a racially/ethnically diverse sample of women with a recent abnormal Pap test. Methods Patients ( n = 640) represent a subset of women participating in a clinical trial. Cervical swabs were tested for HPV16/18 DNA using type-specific polymerase chain reaction assays. Viral integration status was assessed using type-specific integration assays and categorized as fully integrated, fully non-integrated, or mixed. Unconditional logistic regression was used to generate unadjusted (OR) and adjusted odds ratios (aOR) to assess the association between self-reported race/ethnicity and risk of these outcomes. Results Hispanic and non-Hispanic black women had half the odds of prevalent HPV16 compared to non-Hispanic white women (aORs: 0.43 and 0.45, respectively). The prevalence odds of HPV18 was less than half among Hispanic women (aOR: 0.48), but not significantly different between black and white women (aOR: 0.72). Among women with prevalent HPV16, the odds of fully integrated viral DNA were significantly higher among black women (aORs: 2.78) and marginally higher among Hispanic women (aOR: 1.93). No racial/ethnic differences were observed for HPV18 DNA integration. Conclusions While HPV16 and 18 infections were less prevalent among Hispanic and black women compared to whites, their HPV16 DNA was more likely to be present in a fully integrated state. This could potentially contribute to the higher rates of abnormal cytology and cervical dysplasia observed among Hispanic and black women. [ABSTRACT FROM AUTHOR]

Abstract: Altered angiogenic response is associated with high-grade cervical dysplasia and with invasive squamous carcinoma of the cervix. Vascular Endothelial Growth Factor (VEGF) is one of the most potent inducers of angiogenesis and is up-regulated in carcinoma of the cervix. Infection by high-risk human papillomavirus and persistent expression of viral oncogene E6 are etiologically linked to the development of cervical cancer. E6 is able to immortalize cells and induce malignant transformation by inactivating p53. In cervical cancer, regulation of VEGF expression is poorly described. Thus, we investigated whether E6 oncoprotein could regulate VEGF expression in HPV18-positive cervical cancer-derived HeLa cells harboring a wild-type p53. The alternative splicing of vegf mRNA renders three major isoforms of 121, 165 and 189 amino-acids in humans. We have designed isoform specific real time QRT-PCR assays to quantitate vegf transcripts and VEGF121 was the predominant isoform. Silencing HPV18 E6 mRNA with specific siRNA reduced VEGF121 expression by at least 50% whereas silencing of p53 did not alter its expression. Treatment with cycloheximide did not inhibit E6-induced VEGF121 expression. Collectively, these results suggest that HPV18 E6 oncoprotein contributes to tumor angiogenesis by inducing VEGF transcription from the promoter in a p53-independent manner. [Copyright &y& Elsevier]

Abstract: Activation of the productive phase of the human papillomavirus (HPV) life cycle in differentiated keratinocytes is coincident with high-level expression of E1^E4 protein. To determine the role of E1^E4 in the HPV replication cycle, we constructed HPV18 mutant genomes in which expression of the full-length E1^E4 protein was abrogated. Undifferentiated keratinocytes containing mutant genomes showed enhanced proliferation when compared to cells containing wildtype genomes, but there were no differences in maintenance of viral episomes. Following differentiation, cells with mutant genomes exhibited reduced levels of viral DNA amplification and late gene expression, compared to wildtype genome-containing cells. This indicates that HPV18 E1^E4 plays an important role in regulating HPV late functions, and it may also function in the early phase of the replication cycle. Our finding that full-length HPV18 E1^E4 protein plays a significant role in promoting viral genome amplification concurs with a similar report with HPV31, but is in contrast to an HPV11 study where viral DNA amplification was not dependent on full-length E1^E4 expression, and to HPV16 where only C-terminal truncations in E1^E4 abrogated vegetative genome replication. This suggests that type-specific differences exist between various E1^E4 proteins. [Copyright &y& Elsevier]

Abstract: Persistent infections with human papillomaviruses type 18 can result in the development of cervical cancer. HPV18 genomes persist extrachromosomally in low-grade and precancerous lesions but are always integrated in cervical cancers, and this might contribute to the progression of HPV18-induced lesions. To address whether integration induces additional changes in host cells, several keratinocyte lines with wild type and replication-deficient E1 mutant HPV18 (E1C-TTL) genomes were analyzed with high density oligonucleotide arrays. In comparison to normal keratinocytes, wild type and integrated E1C-TTL HPV18 genomes deregulate the expression of 280 annotated genes. However, the comparison of wild type with E1C-TTL cell lines did not reveal any significant differences, indicating that neither the loss of E1 nor viral integration induces additional gene expression changes in low passage HPV18-positive keratinocytes. Half of the deregulated genes have been described as targets of the p16/Rb/E2F, p53, interferon or NFκB pathways consistent with the functions ascribed to the viral E6 and E7 oncoproteins, but the other half can currently not be ascribed to certain pathways. [Copyright &y& Elsevier]

Abstract: Objective. : Addition of high-risk human papillomavirus (hrHPV) testing to post-treatment monitoring policies of women treated for high-grade cervical intraepithelial neoplasia (CIN) may improve the effectiveness of detecting recurrent/residual disease. Recent studies have shown that HPV type 16 confers an increased risk of high-grade CIN and cervical cancer. This study aimed to find out whether the post-treatment CIN3 rate is increased in HPV16-positive women treated for CIN3. Methods. : We included 229 hrHPV-positive women treated for CIN3. HPV typing was performed by GP5+/6+-PCR followed by reverse line blotting on a cervical scrape taken before treatment. HPV typing data were related to the occurrence of post-treatment CIN3 within a median follow-up time of 20.1 months (range 3–85.4 months) following treatment. Results. : Twenty nine of the 151 (19%) HPV16-positive women versus 6 of the 78 (8%) women with other hrHPV types had recurrent/residual CIN3. Post-treatment CIN3 rate was significantly increased in women with HPV16 compared to those harboring other hrHPV types (p =0.03). None of the other hrHPV types were associated with higher post-treatment CIN3 rates. Conclusion. : Women treated for HPV16 containing CIN3 should be monitored more intensively because of their increased risk of post-treatment CIN3. Thus, the HPV genotype should be considered in post-treatment monitoring policies. [Copyright &y& Elsevier]