Human Papillomaviruses 16 and 18 E6 Oncoprotein Detection Test in Primary Oropharyngeal Carcinomas and Metastatic Lymph Nodes: A Cross-Sectional Study

PURPOSE

Accuracy in the diagnosis of HPV-associated oropharyngeal carcinoma (OPSCC) of a rapid, low-cost lateral flow immunochromatographic assay for detecting E6 oncoprotein of HPV-16 and HPV-18 was previously evaluated in a small pilot study. This cross-sectional study aimed to assess on a large case series the sensitivity and specificity of E6 oncoprotein as a diagnostic marker for HPV-associated carcinogenesis in OPSCC.

METHODS

137 consecutive patients with histologically confirmed OPSCC were enrolled in two hospitals in Northeast Italy. HPV status was determined by PCR for HPV DNA and p16INK4a immunohistochemistry on primary tumor biopsies. An OPSCC was defined as HPV-associated when double positive for high-risk HPV-DNA and p16INK4a overexpression in primary lesion. Cytological samples from primary tumors and metastatic lymph nodes were obtained and tested for HPV16/18 E6 oncoproteins using the lateral flow immunochromatographic assay, which requires between 90 and 120 min to provide a result. Diagnostic performances were calculated as percentage with confidence intervals (CI).

RESULTS

Of the 137 OPSCC cases, 68 (49.6%) were HPV-associated, testing positive for both high-risk HPV-DNA and p16INK4a, with HPV16 predominating (82.4%). An average waiting time of 22 days was observed to obtain the results of p16INK4a and HPV-DNA after primary lesions biopsy. In patients with HPV16/18-associated OPSCC, the HPV16/18 E6 oncoprotein was detected in 59 out of 60 cytological samples from the primary lesion (sensitivity: 98.3%; 95% CI: 91.1-100%) and in 45 out of 51 cytological samples from lymph node metastases (sensitivity: 88.2%; 95% CI: 76.1-95.6%). The E6 oncoprotein assay showed a specificity of 100% in both primary tumors and lymph node metastases.

CONCLUSION

The low-cost lateral flow immunochromatographic assay for detecting HPV16/18 E6 oncoproteins confirmed high accuracy for identifying HPV-associated OPSCC, particularly in primary tumors, suggesting its potential as a valuable diagnostic tool in clinical practice. Its rapid diagnostic capability could significantly accelerate the process of treatment decision-making, enhancing the timely management of patients.

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.

Human papillomavirus-related neoplasia of the ocular adnexa

Human papillomaviruses (HPV) are involved in approximately 5% of solid cancers worldwide. The mucosotropic genotypes infect the stratified epithelium of various locations, where persistent infection may lead to invasive carcinomas. While the causative role of HPV in certain anogenital and head and neck carcinomas is well established, the role of HPV in carcinomas arising in the mucosal membranes of the ocular adnexal tissue (the lacrimal drainage system and the conjunctiva) has been a topic of great uncertainty. Therefore, we conducted a series of studies to assess the correlation between HPV and carcinomas arising in the mucosa of the ocular adnexal tissue and characterize the clinical, histopathological, and genomic features of the tumors in the context of HPV status in a Danish nationwide cohort. We collected clinical and histopathological data and tumor specimens from patients with carcinomas of the conjunctiva and the lacrimal drainage system, and their potential precursors, identified in Danish nationwide registries. The HPV status of the tumors was determined by the combined use of HPV DNA polymerase chain reaction (PCR), HPV E6/E7 mRNA in-situ hybridization, and p16 immunohistochemistry. The genomic profile was investigated by high-throughput DNA sequencing targeting 523 cancer-relevant genes. The literature to date on carcinomas of the lacrimal drainage system and the conjunctiva was summarized. In the Danish cohort, 67% of all carcinomas of the lacrimal drainage system and 21% of all conjunctival carcinomas were HPV-positive. HPV16 was the most frequently implicated genotype. A full-thickness expression of the viral oncogenes E6 and E7 was evident in almost all HPV DNA-positive cases. The HPV-positive carcinomas of the conjunctiva and the lacrimal drainage system shared histopathological and genomic features distinct from their HPV-negative counterparts. The HPV-positive carcinomas were characterized by a non-keratinizing morphology, p16 overexpression, high transcriptional activity of HPV E6/E7, and frequent pathogenic variants in the PI3K-AKT signaling cascade. In contrast, the HPV-negative carcinomas were characterized by a keratinizing morphology, lack of p16 and E6/E7 expression, and frequent somatic pathogenic variants in TP53, CDKN2A, and RB1. Among the patients with conjunctival tumors, HPV positivity was associated with a younger age at diagnosis and a higher risk of recurrence. In conclusion, the results support an etiological role of HPV in a subset of conjunctival and LDS carcinomas and their precursor lesions. Our investigations have shown that the HPV-positive carcinomas of the ocular adnexa share genomic and phenotypic characteristics with HPV-positive carcinomas of other anatomical locations. Therefore, these patients may be eligible for inclusion in future basket trials and future treatment regimens tailored to the more frequently occurring HPV-positive carcinomas of other locations. Future research will further elucidate the diagnostic, prognostic, and predictive role of HPV in these carcinomas.

Highly Reproducible and Sensitive Electrochemiluminescence Biosensors for HPV Detection Based on Bovine Serum Albumin Carrier Platforms and Hyperbranched Rolling Circle Amplification

Most DNA-based electrochemiluminescence (ECL) biosensors are established through the self-assembly of thiolated single-stranded DNA (ssDNA) probes on the Au electrode surface. Because of this random assembly process, a significant discrepancy exists in the distribution of a modified DNA film on different electrodes, which greatly affects the reproducibility of a biosensor. In this study, a porous bovine serum albumin (BSA) layer was first modified on the electrode surface, which can improve the position distribution and spatial orientation of the self-assembly ssDNA probe. It was then coupled with hyperbranched rolling circle amplification to develop the high-reproducibility-and-sensitivity ECL biosensor for human papillomavirus 16 E6 and E7 oncogene detection. In the presence of the target DNA, the surface of the electrode accumulates abundant amplified products through reaction, which contain double-stranded DNA (dsDNA) fragments of different lengths, followed by plentiful dichlorotris (1,10-phenanthroline) ruthenium(II) hydrate (Ru(phen)₃²⁺, acting as an ECL indicator) insertion into grooves of dsDNA fragments, and a strong signal can be detected. There is a linear relationship between the signal and the target concentration range from 10 fM to 15 pM, and the detection limit is 7.6 fM (S/N = 3). After the BSA modification step, the relative standard deviation was reduced from 9.20 to 3.96%, thereby achieving good reproducibility. The proposed ECL strategy provides a new method for constructing high-reproducibility-and-sensitivity ECL biosensors.

Characterization of cervical biopsies of women with HIV and HPV co-infection using p16ink4a, ki-67 and HPV E4 immunohistochemistry and DNA methylation

This study aims to characterize cervical intraepithelial neoplasia (CIN) in women living with HIV using biomarkers. Immunohistochemical (IHC) staining for human papillomavirus (HPV) E4 protein indicates CIN with productive HPV infection, whereas Ki-67 and p16ink4a indicate CIN with transforming characteristics, which may be further characterized using DNA hypermethylation, indicative for advanced transforming CIN. Cervical biopsies (n = 175) from 102 HPV positive women living with HIV were independently reviewed by three expert pathologists. The consensus CIN grade was used as reference standard. IHC staining patterns were scored for Ki-67 (0-3), p16ink4a (0-3), and E4 (0-2) and correlated to methylation levels of four cellular genes in corresponding cervical scrapes. Reference standards and immunoscores were obtained from 165 biopsies:15 no dysplasia, 91 CIN1, 31 CIN2, and 28 CIN3. Ki-67 and p16ink4a scores increased with increasing CIN grade, while E4 positivity was highest in CIN1 and CIN2 lesions. E4 positive CIN1 lesions had higher Ki-67 and p16ink4a scores and higher methylation levels compared with E4 negative CIN1 lesions. E4 positive biopsies with low cumulative Ki-67/p16 ink4a immunoscores (0-3) had significantly higher methylation levels compared with E4 negative biopsies. No significant differences in Ki-67 and p16ink4a scores and methylation levels were observed between E4 negative and positive CIN2 or CIN3 lesions. The presence of high methylation levels in scrapes of CIN lesions with IHC characteristics of both productive (E4 positive) and transforming infections (increased Ki-67/p16ink4a expression) in women living with HIV might indicate a rapid aggressive course of HPV infections towards cancer in these women.

[The value of P16/ki67 double labeling, HPV E6/E7 mRNA detection and their combined application in cytological shunt diagnosis of low-grade squamous intraepithelial lesions]

Objective To explore the value of double labeling of P16/ki67, E6/E7 mRNA of human papillomavirus (HPV) and combined detection in shunt diagnosis of low-grade squamous intraepithelial lesions (LSIL) by thin-layer cervical cytology (TCT). Methods The study enrolled 239 patients who underwent colposcopy and biopsy within 4 weeks after primary TCT diagnosis. The remaining cytological samples were double-labeled with P16/ki67 immunocytochemical staining and the HPV E6/E7 mRNA was detected by Panther automatic HPV E6/E7 mRNA detection system. Using SPSS22.0 software, the positive rates of P16/ki67 double-labeling, HPV E6/E7 mRNA and combined detection were analyzed in different cervical lesions, and the positive rates in the same cervical lesions were compared horizontally to evaluate the efficiency of double labeling of P16/ki67, HPV E6/E7 and combined detection in the diagnosis of high-grade squamous intraepithelial lesions (HSIL) and above lesions. Results The diagnostic results of HE staining for the 239 cases of LSIL were 71 cases of chronic cervicitis (29.71%), 143 cases of LSIL (59.83%), 22 cases of HSIL (9.20%) and 3 cases of cervical cancer (1.26%). There were 46 cases of P16⁺ki67⁺ lesions (19.25%), 41 cases of ki67⁺P16^- lesions (17.15%), 33 cases of ki67^-P16⁺ lesions (13.81%) and 119 cases of P16-ki67- lesions (49.79%). The positive rates of P16/ki67 double-labeling, HPV E6/E7 mRNA and combined detection increased with the severity of cervical lesions. The positive rate of combined detection was the highest in the HSIL lesions, which was higher than that of P16/ki67 double-labeling and HPV E6/E7 mRNA detection. The sensitivity of combined detection was higher than that of P16/ki67 double-labeling and HPV E6/E7 mRNA detection. The Youden index of joint detection was 0.7850. Conclusion The combined detection of P16/ki67 double labeling, HPV E6/E7 mRNA and HPV E6/E7 mRNA had a certain clinical value in the management of cell LSIL shunt diagnosis. The combined detection significantly improved the sensitivity and Youden index of HSIL and above lesions, while maintaining a high specificity and coincidence rate.

Performance of OncoE6TM Cervical Test in detecting cervical precancer lesions in HIV-positive women attending an HIV clinic in Bujumbura, Burundi: a cross-sectional study

OBJECTIVE

New rapid and low-cost molecular tests for cervical cancer screening, such as the OncoE6 Cervical Test, are emerging and could be alternatives for low-income and middle-income countries. To this end, we evaluated the clinical performance of the OncoE6 Cervical Test in detecting cervical intraepithelial neoplasia (CIN) among HIV-infected women in Bujumbura, Burundi.

METHODS

From June to December 2017, a cross-sectional study was conducted in 680 HIV-positive women at the University Hospital. Women aged 25-65 years who declared having had vaginal intercourse were consecutively recruited, and cervical specimens for OncoE6, liquid-based cytology and human papillomavirus (HPV) genotyping were obtained and visual inspection with acetic acid performed. Thereafter, participants underwent a colposcopic examination. The sensitivity, specificity, and positive and negative predictive values of the different tests were calculated with reference to 'colposcopic-histological' diagnoses, and areas under the receiver operating curves of OncoE6 and cytology tests were compared.

RESULTS

The prevalence of CIN was 4.9%, and OncoE6 positivity was 3.1%. OncoE6 sensitivity varied from poor to low with increasing disease severity (42.1%, 95% CI 19.9% to 64.3% at CIN2+ threshold; and 58.3%, 95% CI 30.4% to 86.2% at CIN3+ threshold). OncoE6 had the highest specificity compared with all other tests used together. The performance of the OncoE6 test was significantly lower compared with cytology at atypical squamous cell of undetermined significance (ASCUS+) cut-off (AUC=0.68 vs 0.85, p=0.03) and low-grade squamous intraepithelial lesion (LSIL+) cut-off (AUC=0.68 vs 0.83, p=0.04) for CIN2+ diagnoses. However, the performance of the OncoE6 test was similar to that of cytology at high-grade squamous intraepithelial lesion (HSIL+) cut-off (AUC=0.68 vs 0.76; p=0.30) for CIN2+ diagnoses and was also similar to that of cytology at all cut-offs (ASCUS+, LSIL+ and HSIL+) for CIN3+ diagnoses (p1=0.76, p2=0.95 and p3=0.50, respectively).

CONCLUSION

The current OncoE6 test proved to be a point-of-care test. However, given its poor performance for CIN2+ diagnoses, we do not recommend it for primary screening. We recommend to enrich it with more oncogenic HPV types, which may improve the performance of the test akin to that of cytology.

Distribution of HPV-16 and HPV-18 from the Patients Attending At Mymensingh Medical College Hospital by Newly Developed Oncoprotein Detection Assay

Cervical cancer is one of cause of death in women in many developing countries. Persistent infection with Human Papilloma Virus (HPV), primarily high risk types 16 and 18, is recognized as a causal and essential factor for the development of cervical cancer. The objective of this cross sectional observational study is to detect the distribution of HPV-16 and HPV-18 among Onco E6 positive cases. Following universal safety precautions a total of 180 endocervical swabs were collected from Colposcopy clinic of Obstetrics and Gynaecology Department of Mymensingh Medical College Hospital (MMCH), Mymensingh, Bangladesh from January 2016 to December 2016. Laboratory work was done in the department of Microbiology, Mymensingh Medical College. E6 strip test is an immunochromatographic test based on the detection of HPV-E6 oncoprotein in cervical swab samples. Onco E6 cervical test was done on 180cases. Among them 60% were VIA positive and 120% were VIA negative. From this VIA positive cases 12(16.25%) were On E6 cervical test positive and from VIA negative cases 3(2.5%) were positive by this On E6 cervical test. From this 12 Onco E6 cervical test positive cases 10(%) were HPV-16 and 2(%) were HPV-18 and from VIA negative cases 3 were only HPV-16 by this test. Histopathological test done on 35 suspected cases and out of 08 cervical carcinoma cases 07 were positive by this Onco E6 cervical test which was also HPV-16 type. It may be concluded that HPV-16 is most prevalent type to cause cervical cancer and by this newly developed protein detection assay will be helpful to reduce over treatment and save many lives.

[The role of HPV E6/E7 mRNA combined with P16/ki67 immunocytochemistry in the diagnosis of atypical squamous cells of undetermined significance(ASCUS)]

Objective To investigate the diagnostic value of human papillomavirus (HPV) E6/E7 mRNA combined with P16/antigen KI-67(ki67) immunocytochemical double staining in the atypical squamous cells of undetermined significance (ASCUS). Methods A total of 272 patients were selected and the results of HPV E6/E7 and P16/ki67 immunocytochemical double staining in the remaining cytological specimens were retrospectively analyzed. HPV E6/E7 gene was detected by HPV E6/E7 gene detection kit and Panther molecular diagnostic instrument. P16/ki67 was detected by immunocytochemical staining and Ventana Benchmark Ultra immunohistochemical staining instrument. Then we analyzed the difference of positive rate between the two detection methods in the same grade of cervical epithelial lesions, explored the difference of the two detection methods and their combined detection in the diagnosis of high grade squamous intraepithelial lesions (HSIL), and finally evaluated the role of different detection methods in shunt diagnosis of ASCUS. Results Histopathological findings of cervical cytology ASCUS includes chronic cervicitis, low-grade squamous intraepithelial lesions (LSIL), HSIL and cervical cancer. The positive rate of simple molecular diagnosis or immunocytochemical staining increased with the severity of cervical lesions. In cervicitis and LSIL lesion group, the difference between the positive rates of the two methods was obvious, but in HSIL and cervical cancer lesion group, there was no significant difference between the positive rates of the two methods. The sensitivity, specificity, Yoden index, coincidence rate, positive predictive value and negative predictive value were 95.65%, 85.40%, 0.81, 87.13%, 57.14% and 98.97%, respectively. Conclusion The detection of HPV E6/E7 and P16/ki67 immunocytochemical staining has certain significance in ASCUS shunt diagnosis. The combined detection of HPV E6/E7 and P16/ki67 can significantly improve the sensitivity of shunt diagnosis and maintain a good specificity.

Self-sampling coupled to the detection of HPV 16 and 18 E6 protein: A promising option for detection of cervical malignancies in remote areas

Objective

To evaluate both the performance and acceptability of a method coupling self-sampling with detection of cervical malignancy via elevated HPV 16 and 18 E6 oncoproteins (OncoE6™ Cervical Test) in remote areas in Brazil.

Methods

Women living in rural villages in proximity to Coari city, Amazonas, Brazil were invited to participate in a cervical cancer screening study. 412 subjects were enrolled; there were no refusals. In addition to E6 protein detection, DNA was extracted from the brushes and evaluated for HPV genotypes by PCR (PGMY09/11), followed by typing by the Papillocheck™ if positive. Subjects who were found to be positive for OncoE6 or HPV-DNA were referred for colposcopy.

Results

For 110 subjects (27%) this was the first cervical cancer exam. Overall the HPV-DNA prevalence was 19.1% (n = 79); 1.4% (n = 6) were positive by the OncoE6 Test. Fifty-six women attended the invitation for colposcopy where nine had an abnormal cervix and were subsequently biopsied. Histopathological analysis revealed 2 CIN3, 2 carcinomas and 5 CIN1. OncoE6 called two out of the three HPV 16 or 18 associated CIN3+ lesions.

Conclusions

The findings suggest that self-administered sample collection in combination with OncoE6 Test is feasible in this population. This could enable expanded screening coverage while ensuring a high specificity which is imperative given the remote geographic location, since women bearing abnormal test results would necessitate travel and logistical burden to access colposcopy and treatment.

A prospective study of women with ASCUS or LSIL pap smears at baseline and HPV E6/E7 mRNA positive: a 3-year follow-up

Human papillomavirus (HPV) testing is used in the triage of women with a borderline smear result. The efficiency of testing women with a low-grade squamous intraepithelial lesion (LSIL) and atypical squamous cells of undetermined significance (ASCUS) is less clear. For this reason we used a new HPV test that detects E6/E7 messenger RNA (mRNA), which might have a higher specificity. The objective of this prospective study was to assess whether HPV E6/E7 mRNA positivity in women with ASCUS and LSIL at baseline, is able to predict those women who have a high risk of developing a histological cervical intraepithelial neoplasia (CIN2) or worse lesion. We took into consideration the women's age and HPV DNA genotype and followed them up for 3 years. Cervical samples from women with high-risk HPV (HR-HPV) DNA-positive ASCUS (n = 90) or LSIL (n = 222) were tested for the presence of HR-HPV E6/E7 mRNA and the women were monitored for the development of histopathologically verified CIN2+. Thirteen patients with ASCUS and 17 with LSIL did not complete follow-up. All patients with LSIL and ASCUS, enrolled in this study, had confirmed lesions at the colposcopic examination. Follow-up was available for 312 women, 193 were positive in the HR-HPV DNA test and 93 had a HPV E6/E7 mRNA positive test. Finally, 22 women positive in the HPV DNA test for high-risk genotypes and with positive E6/E7 mRNA had a histologically confirmed CIN2+. Only two cases with negative HPV E6/E7 mRNA had CIN2+. The study shows that women positive in the HPV E6/E7 mRNA test have a greater risk of malignant progression of cervical lesions and therefore deserve greater attention and earlier check-ups.

OncoE6 Positivity among VIA Positive Suspected Cases from Colposcopy Clinic of Mymensingh Medical College Hospital, Mymensingh

Cervical cancer is a major world health problem for women. It is the fourth most leading cause of death in women around the world. High risk HPV DNA has been shown to be present in 99.7% of cervical cancers worldwide. Oncoprotein E6 and E7 play an important role in the development of cervical cancer which can be detected by OncoE6 cervical test. This Cross sectional observational study was performed to detect E6 Oncoprotein from cervical swab by OncoE6 cervical test. Following universal safety precautions a total of 47 endocervical swabs were collected from Colposcopy clinic of Obstetrics and Gynaecology department of Mymensingh Medical College Hospital (MMCH), Mymensingh, Bangladesh from January 2015 to December 2015. Laboratory work was done in the department of Microbiology, Mymensingh medical college. E6 strip test is an immunochromatographic test based on the detection of HPV-E6 oncoprotein in cervical swab samples. The swab specimen was treated with lysis solution and conditioning solution. Then the specimen solution was clarified by centrifugation. After that the sample solution was transferred into Detector mAb vial, wash solution vial and finally into developing solution vial. The test unit was then placed on a reading guide. Positive result was indicated by the appearance of purple colored test line. Out of 47 specimens 21(44.68%) were OncoE6 positive by OncoE6 cervical test. Among 21 positive cases 19(90.48%) were HPV-16 and 2 were (9.52%) HPV-18. Histopathologically out of 22 cervical carcinoma cases 20(90.90%) were positive by this test. Based on the findings of the present study, it may be concluded that screening with HPV E6 may minimize the overtreatment as well as the colposcopy referral. So it can be used as primary screening to aid colposcopy and to identify real disease. HPV based screening may help to control cervical cancer in Bangladesh. As HPV is a sexually transmitted infection; so, male screening method should be established.

Risk stratification and long-term risk prediction of E6 oncoprotein in a prospective screening cohort in China

E6 oncoprotein is a necessary agent of HPV driven oncogenic transformation. This study is aimed at evaluating the risk stratification potency of HPV 16/18 E6 oncoprotein (E6) as a triage method for HPV positivity. Moreover, it also acts as a predictor of cervical intraepithelial neoplasia grade 3 or worse (CIN3+). The screening cohort of 1,997 women was followed for a 15 year period in approximate five-year intervals. Participants were concurrently screened by HPV DNA testing (HC2), liquid based cytology (LBC), visual inspection with acetic acid (VIA) and were referred to colposcopy and biopsy if any tests reflected positive. E6 was performed on cervical samples collected from this cohort in 2005 and 2014. The ability of E6 to predict CIN3+ risk after the five- and ten-year interval was evaluated. Among HPV positive women in 2005, E6 indicated the lowest positive rate (9.9%) compared to LBC (48.4%) and VIA (28.0%), however, a higher prevalence rate (10.3%) and 10-year cumulative incidence rate (53.0%) of CIN3+ were detected among women who were E6 positive. Meanwhile, only 4.2% and 2.9% of women with abnormal LBC and positive VIA were diagnosed as prevalent CIN3+ in 2005, 23.0% and 16.5% developed to CIN3+ after year 10, respectively. Strong associations were found between precedent and subsequent HPV persistence and E6 oncoprotein expression (ORadjusted  = 40.0 and 21.2, respectively). E6 oncoprotein could serve as a low-cost, highly specific, strongly indicative point-of-care method in the triage and treatment of HPV positive women.

Immunohistochemical Evaluation of E6/E7 HPV Oncoproteins Staining in Cervical Cancer

BACKGROUND/AIM

High-risk human papillomavirus (HPV) subtypes (i.e. 16 and 18) lead to uterine cervical cancer as well as HPV-positive oropharyngeal cancer (OSCC), a form of head and neck cancer. The induction of HPV-induced cancer is driven by virus-specific oncoproteins E6 and E7. E6 protein of HPV types 16 and 18 interacts with the E3 ubiquitin protein ligase, resulting in ubiquitination and proteolysis of tumor protein p53. E7 inactivates retinoblastoma protein (Rb) by phosphorylation followed by an increase of free eukaryotic transcription factor E2F (E2F) in the cell. This leads to an increase of cyclin-dependent kinase inhibitor p16, that is used as an immunohistochemical marker of HPV-associated OSCC. Unfortunately, p16 is not exclusively increased by E7 oncoprotein in carcinogenesis. Therefore, the aim of this study was to develop an immunohistochemical approach for the direct detection of E6/E7 oncoproteins in uterine cervical cancer as well as in OSCC.

MATERIAL AND METHODS

Paraffin sections of uterine cervical cancer and 130 were analyzed. Immunohistochemical staining protocols were evaluated with tissue slides from patients with cervical dysplasia (CIN III) and squamous epithelial carcinoma tissue with HPV infection. Liver and placental tissues were used as negative controls. E6-Specific antibody (Biorbyt) was used as primary antibody. The polymer staining method and diaminobenzidine were applied for further development. Panels of E7-specific antibodies were tested. Again, the polymer staining method and diaminobenzidine were applied for further development.

RESULTS

E6-Specific antibody revealed specific and intense staining after pre-incubation of tissue slides with citrate buffer solution. Only the E7 antibody obtained from Chemicon showed intense and specific staining in patients with CIN III and squamous epithelial carcinoma tissue. Pre-incubation with proteinase K diminished non-specific reaction.

CONCLUSION

Our results revealed a useful staining protocol for the immunohistochemical evaluation of E6/E7 oncoprotein expression in uterine cervical cancer, as well as in HPV-positive oropharyngeal cancer. Advantages of this method compared to mRNA in situ hybridization of E6/E7 are the much lower costs, as well as the broader applicability in pathological practice.

Human Papilloma Virus as a Biomarker for Personalized Head and Neck Cancer Radiotherapy

A dramatic increase in the incidence of HPV-related oropharyngeal cancer has been reported in some parts of the western world over the past 30 years. They constitute a clinically distinct subgroup of cancers in terms of molecular biology, patient characteristics, and treatment outcome. This chapter describes the molecular characteristics, epidemiology, and demographics of the HPV-related head and neck cancers and discuss available methods to detect HPV-related tumours. The impact of HPV-related biomarkers in clinical studies on radiotherapy only, altered fractionation, modulation of hypoxia, and concurrent chemo- or bio-radiotherapy are reviewed as well as the perspectives of de-escalation and immune-modulation are discussed.

Type-specific detection of human papillomaviruses in Kazakh esophageal squamous cell carcinoma by genotyping both E6 and L1 genes with MALDI-TOF mass spectrometry

BACKGROUND

Many studies have suggested a relationship between human papillomavirus (HPV) infection and the risk of esophageal squamous cell carcinoma (ESCC). However, findings are inconclusive, potentially because of geographic heterogeneity and variations in detection methods.

OBJECTIVES

We sought to further investigate the prevalence of HPV with a new detection method, the MassARRAY Sequenom technique, in esophageal squamous cell carcinomas occurring in patients belonging to Kazakh populations in Xinjiang, China.

STUDY DESIGN

In the present study, a novel genotyping method for detecting 30 HPV genotypes, specifically by genotyping both the HPV E6 and L1 genes with multiplex PCR using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) (PCR-MS) was first adopted to evaluate HPV genotypes in 89 esophageal cancer samples and 49 matched adjacent normal esophageal tissues.

RESULTS

Six HPV genotypes (HPV6, HPV16, HPV33, HPV39, HPV51, and HPV82) were present in at least 51.7% of the esophageal carcinoma tissues, which was significantly greater than 28.6% prevalence among controls (P < 0.05). HPV16 was the most common of all the genotypes investigated (HPV16 prevalence in carcinoma tissue: 49.4%; odds ratio 3.02, 95% confidence interval 1.39-6.53). HPV-positive ESCC patients were generally younger than HPV-negative patients (P = 0.04). In addition, HPV infection was more common in cases of well-differentiated and shallower invasive depth.

CONCLUSIONS

Based on this new detection method, our findings reiterate the possibility that HPV infection (especially HPV16) may be involved in the etiology of esophageal carcinoma in the Kazakh populations and that HPV E6 gene positivity may be associated with prognosis of patients.

[Semi-quantitative detection of HPV L1 capsid protein in exfoliative cytological examination facilitates the differential diagnosis of cervical lesions]

OBJECTIVE

To evaluate the association of human papilloma virus (HPV) L1 capsid protein expression levels with cervical intraepithelial neoplasia (CIN) and its clinical significance.

METHODS

Immunohistochemistry were performed to detect the expression of HPV L1 capsid protein in the cervical exfoliative cytological examination of 153 cases. The intensity (positive unit, PU) was assessed semi-quantitatively using ImagePro Plus image analysis software. The results were evaluated based on histopathologic diagnosis of cervical biopsy.

RESULTS

PU of HPV L1 capsid protein in different cytopathological groups, including normal/inflammation, atypical squamous cells of unknown significance (ASCUS), low-grade squamous intraepithelial lesion (LSIL), high-grade squamous intraepithelial lesion (HSIL), was 46.87±24.46, 27.23±24.30, 24.10±22.45, 9.36±19.82, respectively, and the differences were statistically significant (P<0.01). PU of HPV L1 capsid protein in different histopathological groups, including normal cervixes or chronic cervicitis, LSIL and HSIL, was 41.30±26.66, 24.84±22.18, 8.69±19.20, respectively, and the differences were statistically significant (P<0.01). Patients with high-risk HPV16 and HPV18 had significantly lower PU of HPV L1 capsid protein than those with other high-risk HPV (P<0.01). PU of HPV L1 capsid protein were correlated negatively with both cytopathological groups and histopathological groups of cervical diseases (r=-0.458, P<0.01 and r=-0.441, P<0.01, respectively). PU of HPV L1 capsid protein was not associated with patients' age (P>0.05).

CONCLUSION

Semi-quantitative analysis of HPV L1 capsid protein expression can directly reflect the precancerous progression of cervical cancer.

Evaluation of clinical performance of a novel urine-based HPV detection assay among women attending a colposcopy clinic

BACKGROUND

Human papillomavirus (HPV) testing in urine offers a convenient approach for cervical cancer screening but has previously suffered from limited clinical sensitivity.

OBJECTIVES

We evaluated clinical performance of the prototype Trovagene HPV test, a novel polymerase chain reaction assay that targets the E1 region of the HPV genome and detects and amplifies short fragments of cell-free HPV DNA in urine.

STUDY DESIGN

We conducted a pilot study among 72 women referred to colposcopy following abnormal screening. Participants provided a urine sample prior to clinician-collected cervical sampling and colposcopically-directed punch biopsy. Trovagene HPV test results on urine samples were compared with cervical and urine testing by Linear Array HPV Genotyping Test (LA-HPV) for detection of histologically-confirmed cervical precancerous lesions.

RESULTS

There was high concordance between urine samples tested by the Trovagene HPV test and corresponding cervical (87.5%) and urine (81.9%) samples tested by LA-HPV. The Trovagene HPV test had high sensitivity (92.3% for detecting CIN2/3, and 100% for CIN3), comparable to LA-HPV testing on cervical samples (96.0% and 100%, respectively), and higher than LA-HPV testing on urine samples (80.8% and 90.0%, respectively). In this referral population, the specificity of the Trovagene urine HPV test was non-significantly lower (29% for CIN2/3 and 25% for CIN3) than corresponding estimates of LA-HPV testing on cervical (36% and 28%, respectively) and urine (42% and 38%, respectively) samples.

CONCLUSIONS

This pilot study suggests that the Trovagene HPV test has high sensitivity for urine-based detection of cervical precancer and merits evaluation in larger studies.

[Correlation study of HPV-16 existential status with Th17/Treg cytokines]

OBJECTIVE

To explore the relationship between the presence of HPV-16 DNA and the expression Treg surface marker Foxp3(+), peripheral blood levels of Th17/Treg cell-associated cytokines and explore their roles and significance in cervical cancer progression.

METHODS

Between January 2012 and October 2012 at Shengjing Hospital of China Medical University, a total of 142 HPV16 positive patients were divided into cervical cancer (CC, n = 60), cervical intraepithelial neoplasia (CIN, n = 65) and control group (n = 17). Cervical liquid-based cytological (LBC) samples were collected to detect E2 and E6 genes of HPV type 16 using multiple real-time polymerase chain reaction (PCR). E2/E6 ratio was used to evaluate the physical status of HPV-16 DNA in host cell genome. The SP immunohistochemical method was used to detect the expressions of FOXP3 in cervical lesions. The concentrations of Th17/Treg cell-associated cytokines were detected by enzyme-linked immunosorbent assay (ELISA).

RESULTS

Under the same status of HPV16 DNA in vivo, the levels of Foxp3(+), transforming growth factor-β (TGF-β) and interleukin-10 (IL-10) were significantly higher than those of the control group (P < 0.01) while the levels of interleukin-17 (IL-17) and interleukin-21 (IL-21)were significantly lower than those of the control group (P < 0.05) . In the same disease, HPV16 DNA integration rate grew with the increases of Foxp3(+), TGF-β and IL-10 while IL-17 and IL-21 were opposite. In the different status of HPV16 type DNA, the expression of Foxp3(+) was closely correlated with Federation International of Gynecology and Obstetrics (FIGO) stage, histological grade and lymphnode metastasis (P < 0.05) except for age (P > 0.05).

CONCLUSION

Treg cytokines, HPV16 integration rate and severity of cervical lesions are positively correlated while Th17 cytokines show opposite effects. Th17/Treg cell-associated cytokines may play an important role in the occurrence and development of cervical cancer.

Association of human papillomavirus genomic sequences by polymerase chain reaction in gastric carcinomas in Brazil

OBJECTIVE

To investigate the prevalence of human papillomavirus (HPV) in patients with gastric cancer and compare with a control group.

STUDY DESIGN

Forty paraffin samples of gastric cancer and 40 endoscopic normal mucosa and peripheral blood controls were subjected to examination by polymerase chain reaction for the L1 gene of HPV. The extracted DNA was amplified in 2 reaction systems using 2 pairs of primers: MY09/MY11 and GP+5/GP+6. We used Milli-Q water as negative control and a mixture of 1 microL of human blood plus 0.25 microL of plasmid pBR322 (HPV-16) as positive control.

RESULTS

HPV was found in 4 patients with gastric cancer and 10 patients without cancer.

CONCLUSION

There was no statistically significant difference between the 2 samples (p = 0.077).

[Capsid protein L1 HPV-16 in a modified cervical epithelium]

The 58 cervical biopsies were studied by cytological, histological, immunomorphological methods, electron microscopy and PCR. Expression of L1 was observed only in the differentiated cells of squamous and metaplastic cervical epithelium. At increase of grade of cervical epithelial lesion decrease expression L1 from 75% of cases of CIN1 up to 28.5% of cases of SCC. Not all capsid structures connect with DNA HPV in case of CIN3.

B7-H1 expression model for immune evasion in human papillomavirus-related oropharyngeal squamous cell carcinoma

Human papillomavirus (HPV) is associated with oropharyngeal squamous cell carcinomas. Persistent viral infection is postulated to lead to carcinogenesis, although infection of benign adjacent epithelium is not typically observed. It is known that immune evasive tumor cells can provide an ideal niche for a virus. The B7-H1/PD-1 cosignaling pathway plays an important role in viral immune evasion by rendering CD8+ cytotoxic T cells anergic. We hypothesized that HPV-related oropharyngeal squamous cell carcinomas express B7-H1 as a mechanism for immune evasion. A tissue microarray was utilized, for which HPV E6/E7 mRNA by in situ hybridization was previously performed. Immunohistochemistry was performed to detect B7-H1 and staining was characterized by pattern, distribution, and intensity. B7-H1 was expressed by 84 of the 181 (46.4%) cases. Both tumor cell membranous and cytoplasmic expression were present and cytoplasmic expression was identified in some peritumoral lymphocytes. Expression was analyzed in several different ways and then considered binarily as positive versus negative. Tumors expressing B7-H1 were more likely to be HPV positive (49.2 vs. 34.1 %, p = 0.08). B7-H1 expression showed no correlation with disease recurrence in the entire cohort (OR = 1.09, p = 0.66), HPV positive cohort (OR = 0.80, p = 0.69) or HPV negative cohort (OR = 2.02, p = 0.22). However, B7-H1 expression intensity did correlate with the development of distant metastasis (p = 0.03), and B7-H1 intensity of 3+ (versus all other staining) showed a strong trend towards distant metastasis in the HPV positive (OR = 6.67, p = 0.13) and HPV negative (OR = 9.0, p = 0.13) cohorts. There was no correlation between B7-H1 expression and patient survival for any of the different ways in which staining was characterized, whether binarily, by distribution, intensity, or combined scores. B7-H1 is expressed in the majority of oropharyngeal squamous cell carcinomas with transcriptionally-active HPV. This suggests that B7-H1 expression by tumor cells may play a role in harboring persistent HPV infection.

A molecular beacon-based method for screening cervical cancer

The aim of this study is to develop a new screening method, molecular beacon (MB) imaging, for detection of cervical cancer and to determine its potential clinical applications by examining the sensitivity and specificity of target-specific MBs. Two target-specific molecular beacons were designed and synthesized for survivin and HPV16E6 mRNA. The two designed MBs and a random control MB were used to detect cervical cancer cell lines and a normal cell line. RT-PCR and western blot targeting survivin and HPV16E6 was done for verification. Furthermore the sensitivity and the specificity of the survivin and HPV16E6 mRNA MBs were examined in smears from 125 clinical cervical patients. The survivin and HPV16E6 mRNA MBs generated a strong fluorescence signal in cervical cancer cell lines, but not in the normal cell line, while the random control MB did not generated any signal in both cell lines. The fluorescence intensity correlated well with the gene expression levels in the cells determined by reverse transcription-PCR and Western blot analysis. The clinical sensitivity and the specificity of survivin MB-FITC were 72.5 and 77% while those of HPV16E6 MB-Cy3 were 96.1% and 71.6%, respectively. A parallel test of the two target MBs showed that the sensitivity increased to 98% and the specificity was 70.2%. The survivin and HPV16E6 mRNA MBs showed good reliability and sensitivity. They have great potential for clinical use in cervical cancer screening.

Quantitative measurement of human papillomavirus type 16 e5 oncoprotein levels in epithelial cell lines by mass spectrometry

The high-risk human papillomavirus type 16 (HPV-16) E5 protein (16E5) induces tumors in a transgenic mouse model and may contribute to early stages of cervical carcinogenesis. Although high-risk E5 expression is generally thought to be lost during the progression to cervical carcinoma following integration of HPV DNA into the host genome, episomal viral DNA has been documented in a subset of HPV-16-positive malignant lesions. Numerous studies have shown that transcripts that could potentially encode 16E5 are present in cervical biopsy specimens and cervical cancer cell lines, but the presence of E5 protein has been demonstrated in only two reports that have not been corroborated. In the present study, we show that trypsin cleavage of 16E5 generates a unique four-amino-acid C-terminal peptide (FLIT) that serves as a marker for E5 expression in transfected cells and epithelial cell lines containing integrated and episomal HPV-16 DNA. Following trypsin cleavage, reversed-phase chromatography and mass spectrometry (MS) were used to detect FLIT. Immunoprecipitation assays using a newly generated anti-16E5 antibody confirmed that 16E5 was solely responsible for the FLIT signal, and deuterated FLIT peptide provided an internal standard that enabled us to quantify the number of 16E5 molecules per cell. We show that 16E5 is expressed in the Caski but not in the SiHa cervical cancer cell line, suggesting that 16E5 may contribute to the malignant phenotype of some cervical cancers, even in cells exclusively containing an integrated HPV genome.