Performance of an HPV 16/18 E6 oncoprotein test for detection of cervical precancer and cancer

Field experience with the 8-HPV-type oncoprotein test for cervical cancer screening among HPV-positive women living with and without HIV in LMICs

Overexpression of HPV-oncoproteins E6 and E7 is necessary for HPV-driven cervical carcinogenesis. Hence, these oncoproteins are promising disease-specific biomarkers. We assessed the technical and operational characteristics of the 8-HPV-type OncoE6/E7 Cervical Test in different laboratories using cervical samples from HPV-positive women living with (WLWH) and without HIV. The 8-HPV-type OncoE6/E7 Test (for short: "OncoE6/E7 test") was performed in 2833 HIV-negative women and 241 WLWH attending multicentric studies in Latin America (ESTAMPA study), and in Africa (CESTA study). Oncoprotein positivity were evaluated at each testing site, according to HIV status as well as type-specific agreement with HPV-DNA results. A feedback questionnaire was given to the operators performing the oncoprotein test to evaluate their impression and acceptability regarding the test. The OncoE6/E7 test revealed a high positivity rate heterogeneity across all testing sites (I2: 95.8%, p < .01) with significant lower positivity in WLWH compared to HIV-negative women (12% vs 25%, p < .01). A similar HPV-type distribution was found between HPV DNA genotyping and oncoprotein testing except for HPV31 and 33 (moderate agreement, k = 0.57). Twenty-one laboratory technicians were trained on oncoprotein testing. Despite operators' concerns about the time-consuming procedure and perceived need for moderate laboratory experience, they reported the OncoE6/E7 test as easy to perform and user-friendly for deployment in resource-limited settings. The high positivity rate variability found across studies and subjectivity in test outcome interpretation could potentially results in oncoprotein false positive/negative, and thus the need for further refinements before implementation of the oncoprotein testing in screen-triage-and-treat approaches is warranted.

Value of high‑risk human papillomavirus detection combined with colposcopy in the diagnosis of cervical cancer and precancerous lesions

In the present study, the diagnostic value of high risk-human papillomavirus (HR-HPV) combined with colposcopy for the detection of cervical cancer and precancerous lesions was evaluated. A total of 397 patients with confirmed cervical disease were enrolled between August 2020 and December 2021. According to the pathological diagnosis, the patients were divided into cervical intraepithelial neoplasia grade I (CIN I; n=153 cases), CIN II (n=101 cases), CIN III (n=86 cases) and cervical cancer (n=57 cases) groups. The HR-HPV-positive rate of the patients with different lesion types was compared, and the consistency of colposcopy and pathological examination results were assessed. For cervical cancer and precancerous lesions, the diagnostic value and efficacy of HR-HPV testing, colposcopy and combined HR-HPV testing and colposcopy examination were compared using pathological examination results as the gold standard. The results of the present study demonstrated that in patients with cervical cancer, the positive rate of HR-HPV (100.00%; n=57/57) was higher than that in patients with precancerous lesions, and the positive rate of HR-HPV in patients with CIN I type (36.60%, n=56/153) was lower than that in patients with CIN II (83.17%, n=84/101) and CIN III (82.56%, n=71/86) types (P<0.05). There was no significant difference in the HR-HPV-positive rate between patients with CIN II and CIN III (P>0.05). Cohen's κ coefficient for colposcopy examination and pathological examination of patients with cervical cancer and precancerous lesions was 0.622, the diagnostic accuracy was 90.43% (n=359/397), the positive predictive value was 65.57% (n=40/61), and the negative predictive value was 94.94% (n=319/336). Receiver operating characteristic curve analysis demonstrated that the area under the curve of the combined examination in the diagnosis of cervical cancer and precancerous lesions was 0.904, which was higher than that of colposcopy (0.820) or HR-HPV testing (0.802) alone (P<0.05). The results of the present study indicated that HR-HPV detection combined with colposcopy has diagnostic value for cervical cancer and precancerous lesions.

Accuracy of HPV E6/E7 oncoprotein tests to detect high-grade cervical lesions: a systematic literature review and meta-analysis

BACKGROUND

Cervical carcinogenesis is mediated by the HPV-E6 and E7 oncoproteins, considered as biomarkers usable in managing screen-positive women.

METHODS

We conducted a systematic review and meta-analysis assessing the accuracy of HPV-E6/E7-oncoprotein tests to detect underlying cervical-precancer and cancer. We included studies reporting data on oncoprotein test accuracy detecting cervical intraepithelial neoplasia grade 3 or worse. Random effects logistic regression models were applied for pooling absolute and relative accuracy.

RESULTS

Twenty-two studies were included. Sensitivity and specificity estimates ranged from 54.2% (95%CI: 45.2-63.0) to 69.5% (95%CI:60.8-76.9) and from 82.8% (95%CI: 50.4-95.8) to 99.1 (95%CI: 98.8-99.3), respectively in the population irrespective of HPV status. Higher sensitivity estimates ranging from 60.8% (95%CI: 49.6-70.9) to 75.5% (95%CI: 71.7-78.9) but lower specificity estimates ranging from 83.7% (95%CI: 76.1-89.3) to 92.1% (95%CI: 88.5-94.6) were observed in studies enrolling high-risk-HPV-positive women. Studies recruiting only HIV-positive women showed a pooled sensitivity of 46.9% (95%CI: 30.6-63.9) with a specificity of 98.0% (95%CI: 96.8-98.7).

CONCLUSIONS

The high specificity of oncoprotein tests supports its use for triaging HPV-positive women. However, oncoprotein-negative women would not be recommended to undertake routine screening, requiring further follow-up. Large-scale and longitudinal studies are needed to further investigate the role of E6/E7-oncoprotein detection in predicting the risk of developing cervical pre-cancer and cancer.

Molecular triaging options for women testing HPV positive with self-collected samples

We review developments in molecular triaging options for women who test positive for high-risk human papillomavirus (hrHPV) on self-collected samples in the context of cervical cancer elimination. The World Health Organization (WHO) recommends hrHPV screening as the primary test for cervical screening due to its high sensitivity compared to other screening tests. However, when hrHPV testing is used alone for treatment decisions, a proportion of women of childbearing age receive unnecessary treatments. This provides the incentive to optimize screening regimes to minimize the risk of overtreatment in women of reproductive age. Molecular biomarkers can potentially enhance the accuracy and efficiency of screening and triage. HrHPV testing is currently the only screening test that allows triage with molecular methods using the same sample. Additionally, offering self-collected hrHPV tests to women has been reported to increase screening coverage. This creates an opportunity to focus health resources on linking screen-positive women to diagnosis and treatment. Adding an additional test to the screening algorithm (a triage test) may improve the test's positive predictive value (PPV) and offer a better balance of benefits and risks for women. Conventional triage methods like cytology and visual inspection with acetic acid (VIA) cannot be performed on self-collected samples and require additional clinic visits and subjective interpretations. Molecular triaging using methods like partial and extended genotyping, methylation tests, detection of E6/E7 proteins, and hrHPV viral load in the same sample as the hrHPV test may improve the prediction of cervical intraepithelial neoplasia grade 2 or worse (CIN2+) and invasive cancer, offering more precise, efficient, and cost-effective screening regimes. More research is needed to determine if self-collected samples are effective and cost-efficient for diverse populations and in comparison to other triage methods. The implementation of molecular triaging could improve screening accuracy and reduce the need for multiple clinical visits. These important factors play a crucial role in achieving the global goal of eliminating cervical cancer as a public health problem.

Diagnostic value of high-risk HPV E6/E7 mRNA in patients with ASCUS

OBJECTIVE

To investigate the infection status of high-risk human papillomavirus (HR-HPV) E6/E7 mRNA in patients with a cytological diagnosis of "atypical squamous cells of undetermined significance" (ASCUS) and to analyze the pathogenic rate of different high-risk HPV subtypes combined with biopsy pathological results to provide a more accurate basis for managing ASCUS patients.

METHODS

A total of 1387 patients with ASCUS and HPV E6/E7 mRNA positivity who were referred for colposcopy were retrospectively analyzed. They were divided into HPV16+, 18/45 + and other HR-HPV + groups premenopausal and postmenopausal groups. The pathological results of the biopsy were divided into the LSIL- group (including normal and low-grade squamous intraepithelial lesions) and the HSIL + group (including high-grade squamous intraepithelial lesions and higher lesions). SPSS was used for the analysis.

RESULTS

The age group 31-40 years had the highest level of HPV16+, and HPV18/45 + was the highest in the 41-50 years group. The detection rates of HSIL + in the HPV16+, HPV18/45+, HPV 16/18/45 + and Other HR-HPV + groups were 48.4%, 18.8%, 43.9% and 15.0%, respectively. The infection rates of HPV16/18/45 in postmenopausal and premenopausal women were 42.4% and 34.3%, respectively. In the HPV18/45 group, the incidence of HSIL + was 30.0% in postmenopausal women and 15.0% in premenopausal women (P < 0.01). In the HPV 16 + and Other HR-HPV + groups, the incidence of HSIL + in postmenopausal patients was not significantly different from that in premenopausal patients. The incidence of cervical cancer in postmenopausal patients is significantly higher than that in premenopausal patients.

CONCLUSIONS

Colposcopy referral or further biopsy is recommended for all ASCUS patients with HPV16/18/45E6/E7 mRNA positivity and postmenopausal patients with HR-HPVE6/E7 mRNA positivity. For premenopausal ASCUS patients with other HR-HPV E6/E7 mRNA positivity, colposcopy should be performed if possible, depending on the specific situation, to achieve early detection and diagnosis.

Performance of Cervical Screening a Decade Following HPV Vaccination: The Costa Rica Vaccine Trial

BACKGROUND

We investigated the impact of human papillomavirus (HPV) vaccination on the performance of cytology-based and HPV-based screening for detection of cervical precancer among women vaccinated as young adults and reaching screening age.

METHODS

A total of 4632 women aged 25-36 years from the Costa Rica HPV Vaccine Trial were included (2418 HPV-vaccinated as young adults and 2214 unvaccinated). We assessed the performance of cytology- and HPV-based cervical screening modalities in vaccinated and unvaccinated women to detect high-grade cervical precancers diagnosed over 4 years and the absolute risk of cumulative cervical precancers by screening results at entry.

RESULTS

We detected 95 cervical intraepithelial neoplasia grade 3 or worse (52 in unvaccinated and 43 in vaccinated women). HPV16/18/31/33/45 was predominant (69%) among unvaccinated participants, and HPV35/52/58/39/51/56/59/66/68 predominated (65%) among vaccinated participants. Sensitivity and specificity of cervical screening approaches were comparable between women vaccinated as young adults and unvaccinated women. Colposcopy referral rates were lower in the vaccinated group for HPV-based screening modalities, but the positive predictive value was comparable between the 2 groups.

CONCLUSIONS

Among women approaching screening ages, vaccinated as young adults, and with a history of intensive screening, the expected reduction in the positive predictive value of HPV testing, associated with dropping prevalence of HPV-associated lesions, was not observed. This is likely due to the presence of high-grade lesions associated with nonvaccine HPV types, which may be less likely to progress to cancer.

A dual-signal electrochemical immunosensor for the detection of HPV16 E6 oncoprotein based on PdBP dendritic ternary nanospheres and MBSi-Chi nanocomposites

A dual-signal electrochemical immunosensor was fabricated to detect HPV16 E6 oncoprotein for the first time, which meets the requirements for a quick and sensitive detection.

Human Papillomaviruses-Associated Cancers: An Update of Current Knowledge

Human papillomaviruses (HPVs), which are small, double-stranded, circular DNA viruses infecting human epithelial cells, are associated with various benign and malignant lesions of mucosa and skin. Intensive research on the oncogenic potential of HPVs started in the 1970s and spread across Europe, including Croatia, and worldwide. Nowadays, the causative role of a subset of oncogenic or high-risk (HR) HPV types, led by HPV-16 and HPV-18, of different anogenital and head and neck cancers is well accepted. Two major viral oncoproteins, E6 and E7, are directly involved in the development of HPV-related malignancies by targeting synergistically various cellular pathways involved in the regulation of cell cycle control, apoptosis, and cell polarity control networks as well as host immune response. This review is aimed at describing the key elements in HPV-related carcinogenesis and the advances in cancer prevention with reference to past and on-going research in Croatia.

Molecular markers for cervical cancer screening

INTRODUCTION

Cervical cancer remains a significant healthcare problem, notably in low- to middle-income countries. While a negative test for hrHPV has a predictive value of more than 99.5%, its positive predictive value is less than 10% for CIN2+ stages. This makes the use of a so-called triage test indispensable for population-based screening to avoid referring women, that are ultimately at low risk of developing cervical cancer, to a gynecologist. This review will give an overview of tests that are based on epigenetic marker panels and protein markers.

AREAS COVERED

There is a medical need for molecular markers with a better predictive value to discriminate hrHPV-positive women that are at risk of developing cervical cancer from those that are not. Areas covered are epigenetic and protein markers as well as health economic considerations in view of the fact that most cases of cervical cancer arise in low-to-middle-income countries.

EXPERT OPINION

While there are biomarker assays based on changes at the nucleic acid (DNA methylation patterns, miRNAs) and at the protein level, they are not widely used in population screening. Combining nucleic acid-based and protein-based tests could improve the overall specificity for discriminating CIN2+ lesions that carry a low risk of progressing to cervical cancer within the screening interval from those that carry an elevated risk. The challenge is to reduce unnecessary referrals without an undesired increase in false-negative diagnoses resulting in cases of cervical cancer that could have been prevented. A further challenge is to develop tests for low-and middle-income countries, which is critical to reduce the worldwide burden of cervical cancer.

Adjunctive testing by cytology, p16/Ki-67 dual-stained cytology or HPV16/18 E6 oncoprotein for the management of HPV16/18 screen-positive women

High-risk human papillomavirus type 16/18 (HPV16/18) genotyping is unable to accurately discriminate nonprogressive infections from those that will progress to cervical cancer. Our study aimed to assesses if additional testing either with liquid-based cytology (LBC) or the putative progression markers p16/Ki-67 and HPV16/18 E6 oncoprotein (E6) can improve the efficiency of HPV16/18 genotyping for triaging high-risk HPV (hrHPV)-positive women through better cancer risk stratification. Women attending colposcopy after positive HPV16/18 genotyping results within the Forwarding Research for Improved Detection and Access for Cervical Cancer Screening and Triage (FRIDA) hrHPV-based screening study in Tlaxcala, Mexico, underwent further testing with LBC, p16/Ki-67 dual-stained (DS) cytology and E6. We calculated measures of test performance for detecting histologically confirmed cervical intraepithelial neoplasia grade 2 or higher (CIN2+) and grade 3 or higher (CIN3+). A number of 475 (64.3%) of 739 HPV16/18-positive women had complete results for all tests. Triage positivity rates were 14.1%, 18.5% and 24.4%, for LBC, E6 and DS, respectively. Compared with LBC, DS had higher sensitivity (24.4% vs 60.0%) although lower specificity (87.0% vs 79.3%) for CIN3+ (P < .001), whereas E6 had a sensitivity of 37.8% and a specificity of 83.5%. No invasive cancer was missed by DS or E6, but 75% were in normal cytology. DS test was associated with nearly 75% reduction of colposcopy referrals compared with the direct referral of all HPV16/18-positive women, giving the least number of colposcopies (n = 4.3) per CIN3+ detected. We show that adjunctive testing of HPV16/18-positive women with DS may greatly reduce unnecessary colposcopy referrals within HPV-based screening employing HPV16/18 genotyping while retaining acceptable sensitivity for CIN2+ and CIN3+.

Development of a sensitive and specific nanoparticle-assisted PCR assay for detecting HPV-16 and HPV-18 DNA

Carcinoma precursor lesion caused by persistent infection of human papillomavirus (HPV) types 16 and 18 is known as a principal inducer of cervical cancer. Therefore, rapid and effective detection of HPV-16 and HPV-18 infection at early stage is an important strategy for preventing such disease. In this study, a novel duplex nanoparticle-assisted polymerase chain reaction (nanoPCR) assay was developed to detect both of the two genotypes simultaneously. Two pairs of primers for nanoPCR were designed based on the conserved region within the early 6 (E6) gene of HPV-16 and HPV-18, respectively. After optimizing reaction conditions, the nanoPCR assay displayed 10-fold more sensitive than that of conventional PCR and showed high specificity. The detection limit of nanoPCR was 1.7 × 101  copies/μL for HPV-16, 1.2 × 102  copies/μL for HPV-18, and no cross-reaction was detected after using other viruses or HPV subtypes as templates. Of 209 clinical samples collected from patients, as also confirmed by sequencing, the nanoPCR method gave consistent results with conventional PCR assay: 7 positives for HPV-16, 4 positives for HPV-18, and no co-infection. Here is the first report to introduce a reproducible nanoPCR assay for detecting HPV DNA with high sensitivity and specificity, which may point out a useful diagnostic tool for potential clinical application.

Multicentric study of cervical cancer screening with human papillomavirus testing and assessment of triage methods in Latin America: the ESTAMPA screening study protocol

INTRODUCTION

Human papillomavirus (HPV) testing is replacing cytology in primary screening. Its limited specificity demands using a second (triage) test to better identify women at high-risk of cervical disease. Cytology represents the immediate triage but its low sensitivity might hamper HPV testing sensitivity, particularly in low-income and middle-income countries (LMICs), where cytology performance has been suboptimal. The ESTAMPA (EStudio multicéntrico de TAMizaje y triaje de cáncer de cuello uterino con pruebas del virus del PApiloma humano; Spanish acronym) study will: (1) evaluate the performance of different triage techniques to detect cervical precancer and (2) inform on how to implement HPV-based screening programmes in LMIC.

METHODS AND ANALYSIS

Women aged 30-64 years are screened with HPV testing and Pap across 12 study centres in Latin America. Screened positives have colposcopy with biopsy and treatment of lesions. Women with no evident disease are recalled 18 months later for another HPV test; those HPV-positive undergo colposcopy with biopsy and treatment as needed. Biological specimens are collected in different visits for triage testing, which is not used for clinical management. The study outcome is histological high-grade squamous intraepithelial or worse lesions (HSIL+) under the lower anogenital squamous terminology. About 50 000 women will be screened and 500 HSIL+ cases detected (at initial and 18 months screening). Performance measures (sensitivity, specificity and predictive values) of triage techniques to detect HSIL+ will be estimated and compared with adjustment by age and study centre.

ETHICS AND DISSEMINATION

The study protocol has been approved by the Ethics Committee of the International Agency for Research on Cancer (IARC), of the Pan American Health Organisation (PAHO) and by those in each participating centre. A Data and Safety Monitoring Board (DSMB) has been established to monitor progress of the study, assure participant safety, advice on scientific conduct and analysis and suggest protocol improvements. Study findings will be published in peer-reviewed journals and presented at scientific meetings.

TRIAL REGISTRATION NUMBER

NCT01881659.

Correlation of APOBEC3G Polymorphism with Human Papillomavirus (HPV) Persistent Infection and Progression of Cervical Lesions

BACKGROUND We studied the effect of APOBEC3G on persistent human papillomavirus (HPV) infection and the correlation between APOBEC3G polymorphism and HPV persistent infection and cervical disease progression in Uygur women in China. MATERIAL AND METHODS From January 2015 to December 2017, we enrolled 529 Uygur ethnic group patients with HPV infection. SIHA cells were transfected with APOBEC3G. Real-time quantitative polymerase chain reaction (RT-qPCR) and Western blot analysis were used to detect mRNA and protein expression levels of APOBEC3G and HPV E6 and p53. Exon 3 of APOBEC3G was sequenced by first-generation sequencing. RESULTS The mRNA and protein expression levels of APOBEC3G in the cervical cancer group were significantly higher than in the cervical intraepithelial neoplasia (CIN) group (p<0.05). The mRNA and protein expression levels of APOBEC3G in the CIN group were significantly higher than in the non-cervical lesions group (p<0.05). The mRNA and protein expression levels of HPV E6 in SIHA cells transfected with APOBEC3G were significantly lower than in the control group and the no-load group (p<0.05), and the mRNA and protein expression levels of p53 were significantly higher than in the control group and the no-load group (p<0.05). There was a polymorphic locus rs5757465 on exon 3 of APOBEC3G in Uygur women, and this rare CC type was a risk factor for cervical lesions and cervical cancer (OR=3.714, 95%CI: 1.916-7.202, p<0.05). CONCLUSIONS APOBEC3G is involved in continuous HPV infection, cervical prelesions, and the development of cervical cancer, and the rare genotype (CC) of APOBEC3G may be one of the factors causing cervical lesions in Uygur women who have HPV infection.