Human papillomavirus (HPV) genome status & cervical cancer outcome--A retrospective study

CRISPR-Based Multiplex Detection of Human Papillomaviruses for One-Pot Point-of-Care Diagnostics

The World Health Organization's global initiative toward eliminating high-risk Human Papillomavirus (hrHPV)-related cancers recommends DNA testing over visual inspection in all settings for primary cancer screening and HPV eradication by 2100. However, multiple hrHPV types cause different types of cancers, and there is a pressing need for an easy-to-use, multiplex point-of-care diagnostic platform for detecting different hrHPV types. Recently, CRISPR-Cas systems have been repurposed for point-of-care detection. Here, we established a CRISPR-Cas multiplexed diagnostic assay (CRISPRD) to detect cervical cancer-causing hrHPVs in one reaction (one-pot assay). We harnessed the compatibility of thermostable AapCas12b, TccCas13a, and HheCas13a nucleases with isothermal amplification and successfully detected HPV16 and HPV18, along with an internal control in a single-pot assay with a limit of detection of 10 copies and 100% specificity. This platform offers a rapid and practical solution for the multiplex detection of hrHPVs, which may facilitate large-scale hrHPV point-of-care screening. Furthermore, the CRISPRD platform programmability enables it to be adapted for the multiplex detection of any two nucleic acid biomarkers as well as internal control.

Rapid detection of HPV16/18 based on a CRISPR-Cas13a/Cas12a dual-channel system

PURPOSE

cervical cancer is the leading cause of cancer deaths in women in the developing world, with high-risk HPV16 and HPV18 accounting for approximately 70% of all cervical cancers. Early detection of HPV, especially high-risk HPV types, is essential to prevent disease progression.

METHODS

in this study, we established a highly sensitive and specific nucleic acid assay based on a CRISPR-Cas13a/Cas12a dual-channel system combined with multiplex RAA for rapid detection and typing of HPV16/18, which provides a new idea for cervical cancer screening. To meet the application of field testing, we designed a portable fluorescence imaging assay that can judge the test results directly with the naked eye or through cell phone imaging.

RESULTS

the lower limit of detection for both HPV16 and HPV18 based on the CRISPR-Cas12a/Cas13a dual-channel assay was 10⁰ copies per μL. The dual-channel assay was validated with 55 clinical samples, showing 97.06% sensitivity, 100% specificity, 100% positive predictive value, and 96.55% negative predictive value. The results of the portable fluorescence imaging assay were fully comparable to those of the real-time fluorescent RAA-based CRISPR-Cas12a/Cas13a dual-channel assay.

CONCLUSIONS

this developed portable dual gene assay platform may provide new technical support for cervical cancer screening in resource-limited settings.

HPV and radiosensitivity of cervical cancer: a narrative review

Background and Objective

Cervical cancer (CC), the most common gynecological malignancy, is divided into two categories: human papillomavirus-related [HPV positive (HPV+)] and non-HPV-related [HPV negative (HPV-)]. Compared with HPV- CC, HPV+ CC has better radiosensitivity and prognosis. We conducted a literature search and summarized relevant studies to explore the detailed mechanisms by which HPV+ improves the prognosis of CC compared to HPV-.

Methods

PubMed was used to search the literature on human papillomavirus, cervical cancer, and radiotherapy up to June 2022.

Key Content and Findings

Compared with HPV- CC, HPV+ CC has better radiotherapy outcomes and better prognosis. HPV improves the radiotherapy sensitivity of CC by inhibiting damaged DNA repair, increasing cell cycle arrest, reducing hypoxia, increasing cellular immune response, and other mechanisms. However, the effect of HPV on radiotherapy sensitivity of CC is not consistent and is affected by HPV type, viral load, and many other factors. Partial HPV+ CCs, due to hypoxia and other factors, are resistant to radiotherapy and have a poor prognosis. HPV- CC has poor radiotherapy sensitivity and poor prognosis. With the spread of the vaccine, HPV- CC will gradually increase, which is a cause for concern.

Conclusions

The radiosensitivity was significantly increased in patients with HPV+ CC, compared to HPV- patients. HPV improves the radiotherapy sensitivity of cervical cancer through a number of pathways. Meanwhile, the relationship between HPV and radiotherapy sensitivity is influenced by a number of factors. Some HPV+ CCs showed radiotherapy resistance, and HPV- CCs deserve further attention.

The Role of Extracellular Vesicles in Cancer-Nerve Crosstalk of the Peripheral Nervous System

Although the pathogenic operations of cancer–nerve crosstalk (e.g., neuritogenesis, neoneurogensis, and perineural invasion—PNI) in the peripheral nervous system (PNS) during tumorigenesis, as well as the progression of all cancer types is continuing to emerge as an area of unique scientific interest and study, extensive, wide-ranging, and multidisciplinary investigations still remain fragmented and unsystematic. This is especially so in regard to the roles played by extracellular vesicles (EVs), which are lipid bilayer-enclosed nano- to microsized particles that carry multiple-function molecular cargos, facilitate intercellular communication in diverse processes. Accordingly, the biological significance of EVs has been greatly elevated in recent years, as there is strong evidence that they could contribute to important and possibly groundbreaking diagnostic and therapeutic innovations. This can be achieved and the pace of discoveries accelerated through cross-pollination from existing knowledge and studies regarding nervous system physiology and pathology, as well as thoroughgoing collaborations between oncologists, neurobiologists, pathologists, clinicians, and researchers. This article offers an overview of current and recent past investigations on the roles of EVs in cancer–nerve crosstalk, as well as in neural development, physiology, inflammation, injury, and regeneration in the PNS. By highlighting the mechanisms involved in physiological and noncancerous pathological cellular crosstalk, we provide hints that may inspire additional translational studies on cancer–nerve interplay.

Prognosis of Human Papillomavirus-Negative Compared to Human Papillomavirus-Positive Cervical Cancer

OBJECTIVES

The aims of the study were to evaluate the prevalence and prognosis of human papillomavirus (HPV)-negative cervical cancer (CC) and to compare these to data for HPV-positive CC.

MATERIALS AND METHODS

This retrospective cohort study compared between HPV-negative CC and HPV-positive CC patients. Primary end points were disease-free survival and overall survival. Secondary end points were demographic and clinical variables including histological diagnosis, stage, and treatment.

RESULTS

Of 233 women with CC, 18 (8%) tested HPV-negative. During a median follow-up of 45 months, 33 (14%) recurrences and 41 (18%) deaths were observed. Eleven of the 18 women (61%) who tested HPV-negative and 41 of the 215 (19%) who tested HPV-positive had only adenocarcinoma (p < .001). In a multivariate logistic regression analysis, advanced age (p = .003) and primary treatment with chemotherapy and/or radiotherapy (p < .001) remained statistically significant for recurrence or mortality (disease-free survival). The factors associated with lower survival were advanced age (p = .008), higher stage at diagnosis (p < .001), and HPV negativity (p = .062). Median overall survival for HPV-positive CC was not reached, compared with 24 months for HPV-negative CC. Kaplan-Meier curves showed lower rates of disease-free survival (p = .008) and overall survival (p = .011), for women with HPV-negative compared with HPV-positive CC.

CONCLUSIONS

The relatively poor prognosis of HPV-negative CC is important in light of its relatively high prevalence, which could increase proportionally to HPV-positive CC due to increased HPV screening and vaccination. Further studies are needed to confirm whether HPV status is truly an independent prognostic factor in CC.

Human papillomavirus and ovarian cancer (review of literature and meta-analysis)

Many factors are involved in carcinogenesis of the ovary, such human genetic and physiological characteristics as lifestyle, existing diseases of the reproductive system, and, as suggested, the human papillomavirus (HPV). It is well known that the human papillomavirus virus of high carcinogenic risk (HCR) plays a crucial role in the onset and development of cervical cancer, as well as cases of HPV positive breast cancer and endometrial cancer. The data on the presence of HPV in ovarian cancer are ambiguous: the researchers claim that there is no complete effect of the virus on the development of this type of cancer, and the detection of HPV in 60-80% of tumors. In this regard, there is a need to systematize the currently available research results on this controversial issue and conduct a meta-analysis of the association of HPV infection with the risk of ovarian cancer.

Contribution of Tata Memorial Centre, India, to cervical cancer care: Journey of two decades

Cervical cancer continues to be a major public health concern in India and other low- and middle-income countries. Tata Memorial Centre, India, has been at the forefront in providing treatment, developing best practice guidelines for low-cost efficacious interventions, conducting practice-changing randomized trials and engaging in regional and international collaborations for education and research in cervical cancer. This review summarizes how cervical cancer research and clinical care has evolved over the past two decades at the Tata Memorial Centre, right from testing low-cost public health screening of cervical cancers to the incorporation of the latest technological advancements and providing high-quality evidence for therapeutic management of cervical cancer. The various ongoing strategies for improving survival, toxicity reduction, translational research studies, educational activities and teaching programmes initiated by the Tata Memorial Centre at both national and international levels are discussed.

Pathogenic Role of Immune Evasion and Integration of Human Papillomavirus in Oropharyngeal Cancer

The incidence of oropharyngeal cancer (OPC) is increasing remarkably among all head and neck cancers, mainly due to its association with the human papillomavirus (HPV). Most HPVs are eliminated by the host’s immune system; however, because HPV has developed an effective immune evasion mechanism to complete its replication cycle, a small number of HPVs are not eliminated, leading to persistent infection. Moreover, during the oncogenic process, the extrachromosomal HPV genome often becomes integrated into the host genome. Integration involves the induction and high expression of E6 and E7, leading to cell cycle activation and increased genomic instability in the host. Therefore, integration is an important event in oncogenesis, although the associated mechanism remains unclear, especially in HPV-OPC. In this review, we summarize the current knowledge on HPV-mediated carcinogenesis, with special emphasis on immune evasion and integration mechanisms, which are crucial for oncogenesis.

Detailed Characteristics of Tonsillar Tumors with Extrachromosomal or Integrated Form of Human Papillomavirus

The human papillomavirus (HPV) integration, the critical step in viral carcinogenesis, most frequently occurs in the E2 gene, which results in its inactivation and in an increase of E6/E7 transcription. However, in a substantial number of tumors, the virus is present in an extrachromosomal form. For those tumors, the transformation mechanisms are not fully elucidated. Here we evaluated the possible mechanism of inactivating the E2 without interruption of the gene, methylation or mutation of the E2 binding sites (E2BSs) in HPV16-positive tonsillar tumors by next-generation and Sanger sequencing. Viral genome status was analyzed by the amplification of papillomavirus oncogene transcripts assay (APOT) and mRNA mapping, and expression of viral oncogenes was performed by qPCR. The methylation of E2BSs was significantly higher in tumors with an integrated, in comparison to extrachromosomal, form of the viral genome. No mutations were detected in the E2BSs. The viral oncogenes were equally expressed in samples with an integrated and extrachromosomal form of the virus. Only the nucleotide variants were identified in the E2 gene. No proposed mechanism of E2 inactivation was confirmed in tonsillar tumors with an extrachromosomal form of the HPV genome. The expression of E6/E7 genes seems to be sufficient to initiate and maintain the carcinogenic process.

Innervation of cervical carcinoma is mediated by cancer-derived exosomes

OBJECTIVE

Recently, our laboratory identified sensory innervation within head and neck squamous cell carcinomas (HNSCCs) and subsequently defined a mechanism whereby HNSCCs promote their own innervation via the release of exosomes that stimulate neurite outgrowth. Interestingly, we noted that exosomes from human papillomavirus (HPV)-positive cell lines were more effective at promoting neurite outgrowth than those from HPV-negative cell lines. As nearly all cervical tumors are HPV-positive, we hypothesized that these findings would extend to cervical cancer.

METHODS

We use an in vitro assay with PC12 cells to quantify the axonogenic potential of cervical cancer exosomes. PC12 cells are treated with cancer-derived exosomes, stained with the pan-neuronal marker (β-III tubulin) and the number of neurites quantified. To assess innervation in cervical cancer, we immunohistochemically stained cervical cancer patient samples for β-III tubulin and TRPV1 (sensory marker) and compared the staining to normal cervix.

RESULTS

Here, we show the presence of sensory nerves within human cervical tumors. Additionally, we show that exosomes derived from HPV-positive cervical cancer cell lines effectively stimulate neurite outgrowth.

CONCLUSIONS

These data identify sensory nerves as components of the cervical cancer microenvironment and suggest that tumor- derived exosomes promote their recruitment.

Nomograms based on HPV load for predicting survival in cervical squamous cell carcinoma: An observational study with a long-term follow-up

Objective

To investigate the prognostic value of pretreatment human papillomavirus (HPV) viral load for cervical cancer, and to develop nomograms based on HPV load and other clinicopathological factors for long-term survival.

Methods

We conducted a prospective study on cervical squamous cell carcinoma (SCC) patients diagnosed between January 2003 and December 2008. Cervical samples were tested for HPV viral load by the Hybrid Capture II (HCII) assay before treatment and 6 months after treatment. Clinical characteristics and follow-up information were also collected. A multivariable Cox proportional hazards model was used to adjust covariates in both the radical hysterectomy (RH) treatment group and concurrent chemoradiotherapy (CCRT) treatment group to identify relevant covariates, and then nomograms were constructed and used for internal validation.

Results

A total of 520 SCC patients enrolled in this study with a median follow-up of 127 months, 360 patients received RH, whereas 160 patients received CCRT. The median HPV viral load in RH and CCRT groups was 356.10 and 294.29, respectively. Tumor size was positively correlated with high pretreatment HPV load in both groups. In CCRT group, the advanced International Federation of Gynecology and Obstetrics (FIGO) stage and enlarged retroperitoneal lymph node status determined by computed tomography (LNSCT) were correlated with low HPV load group. Initial HPV viral load, FIGO stage and lymph node metastasis were prognostic factors for RH group, whereas HPV viral load, squamous cell carcinoma antigen (SCC-Ag) level and LNSCT were identified as prognostic factors for CCRT group. Nomograms incorporating these predictors for 10-year progression-free survival (PFS) were constructed [concordance index (C-index): 0.756, 0.749].

Conclusions

A low pretreatment HPV viral load is an independent prognostic factor for poor prognosis of cervical SCC and is related to other clinicopathological factors. The survival nomogram based on HPV viral load could predict the long-term prognosis.

Characterization of HPV integration, viral gene expression and E6E7 alternative transcripts by RNA-Seq: A descriptive study in invasive cervical cancer

Scarce data are available on the expression of papillomavirus genome and the frequency of alternatively spliced E6E7 mRNAs in invasive cervical cancer. We carried out a comprehensive characterization of HPV expression by RNA-Seq analysis in 22 invasive cervical cancer with HPV16 or HPV18, characterizing the presence of integrated/episomal viral DNA, the integration sites in human genome and the proportion of alternative splicing products of E6 and E7 genes. The expression patterns suggested the presence of episomal and/or integrated viral DNA, with integration detected in most tumors, frequently occurring within human genes in HPV18+ and in intergenic regions in HPV16+ tumors. Alternative splicing of E6E7 transcripts showed E6*I as the most frequent isoform for both viral types, followed by E6*II and E6/E7 (unspliced) transcripts in HPV16+, and by E6/E7 in HPV18+ tumors. Previously described E6*VI and E6*V transcript isoforms for HPV16, and E6*X for HPV18, were rare or not detected.

Patients with integrated HPV16 in head and neck cancer show poor survival

OBJECTIVES

We previously reported identifying three categories of HPV16-positive head and neck tumors based on The Cancer Genome Atlas (TCGA) RNA and DNA sequence data. Category 1 had truly integrated HPV16 genomes, category 2 had simple episomal genomes, and category 3 had novel episomes that were a hybrid between viral and human DNA. Using our categorization, we investigated in this study survival of patients with integrated HPV16 tumors versus patients with episomal HPV16 tumors.

MATERIALS AND METHODS

The TCGA RNA-Seq sequence reads were used to quantify HPV E2 and E7 gene expression, which was used as a marker for HPV integration.

RESULTS

The results demonstrate that integration is associated with poor survival; those patients with integrated HPV tumors fared no better than non-HPV tumors in their five-year survival. Integrated HPV in tumors was found strikingly to be prevalent in patients born earlier while episomal HPV was prevalent in patients born later. We also observed a fairly constant incidence of all HPV forms among head and neck cancer patients over the last eight years of this study (2006-2013).

CONCLUSION

We propose our characterization of HPV integrated and episomal state is more accurate than previous studies that may have mischaracterized the hybrid HPV-human DNA episomes as integrated. The state of integrated HPV is associated with a poor clinical outcome. Results suggest that the incidence of integrated HPV among all HPV forms peaked and is decreasing. We discuss the importance of our findings for the management of HPV positive head and neck cancer.

Human Papillomavirus Type 16 Integration Analysis by Real-time PCR Assay in Associated Cancers

Human papillomavirus (HPV) is a common viral infection worldwide associated with a variety of cancers. The integration of the HPV genome in these patients causes chromosomal instability and triggers carcinogenesis. The aim of this study was to investigate the HPV-16 genome physical status in four major cancers related to HPV infection. Formalin-fixed paraffin-embedded blocks from our previous projects on head and neck, colorectal, penile, and cervical cancers were collected, and HPV-16–positive specimens were used for further analysis. The DNA extraction copy number of E2 and E7 genes was calculated by qualitative real-time PCR method. Serially diluted standards that were cloned in PUC57 plasmid were used. Standard curve and melting curve analysis was used for quantification. Of the 672 specimens studied, 76 (11.3%) were HPV-16 positive. We found that 35.6% (16/45) were integrated. Statistical analysis showed that there were significant correlations between integration of HPV-16 and cervical cancer end-stage carcinogenesis (P < .0001), episomal form, and ASCUS lesions (P = .045). Significant correlation in penile cancer patients was seen between the episomal form and high-grade cancer stage (P = .037). Integration is a major factor in the carcinogenesis mechanism of HPV and has different prevalence in various cancers with a higher rate in progression except in penile cancer.

Comparative analysis of HPV16 gene expression profiles in cervical and in oropharyngeal squamous cell carcinoma

Human papillomavirus type 16 (HPV16) is the major cause of cervical cancer and of a fraction of oropharyngeal carcinoma. Few studies compared the viral expression profiles in the two types of tumor. We analyzed HPV genotypes and viral load as well as early (E2/E4, E5, E6, E6*I, E6*II, E7) and late (L1 and L2) gene expression of HPV16 in cervical and oropharyngeal cancer biopsies. The study included 28 cervical squamous cell carcinoma (SCC) and ten oropharyngeal SCC, along with pair-matched non-tumor tissues, as well as four oropharynx dysplastic tissues and 112 cervical intraepithelial neoplasia biopsies. Viral load was found higher in cervical SCC (<1 to 694 copies/cell) and CIN (<1 to 43 copies/cell) compared to oropharyngeal SCC (<1 to 4 copies/cell). HPV16 E2/E4 and E5 as well as L1 and L2 mRNA levels were low in cervical SCC and CIN and undetectable in oropharynx cases. The HPV16 E6 and E7 mRNAs were consistently high in cervical SCC and low in oropharyngeal SCC. The analysis of HPV16 E6 mRNA expression pattern showed statistically significant higher levels of E6*I versus E6*II isoform in cervical SCC (p = 0.002) and a slightly higher expression of E6*I versus E6*II in oropharyngeal cases. In conclusion, the HPV16 E5, E6, E6*I, E6*II and E7 mRNA levels were more abundant in cervical SCC compared to oropharyngeal SCC suggesting different carcinogenic mechanisms in the two types of HPV-related cancers.

Cancer cervix: Establishing an evidence-based strategy, an experience of a tertiary care centre in India

Carcinoma cervix is a common cancer among Indian women. Evidence based management is essential for best practice in treatment of carcinoma cervix for its effective control. The current imaging system like CT, MRI and PET CT scans have contributed in identifying the patients for optimal treatment and delivering treatment accurately. For stages IB2 to IV, concurrent chemoradiation is advocated with improvement in overall survival proven with randomized trials. Brachytherapy is an integral part in the radiation treatment. Imaged-guided brachytherapy using MRI is desirable, however less expensive imaging modalities such as CT and ultrasonography has been evaluated. In special situation such as for HIV positive patients and patients with neuroendocrine tumors have role of radiotherapy. For further improvement in control of cancer, it is required to integrate basic research to answer clinically relevant questions.

Analysis of human papilloma virus type 52 integration status in exfoliated cervical cells

To explore the significance of human papilloma virus type 52 (HPV52) infection and its integration in cells within cervical lesions, the expression levels of HPV52 were detected using polymerase chain reaction (PCR). The copy numbers of HPV52 E2, HPV52 E6 and the reference gene β-actin were determined by quantitative PCR to analyze the association between HPV52 integration and cervical lesions. HPV52 integration was analyzed by the amplification of papillomavirus oncogene transcripts. A total of 13 samples from 468 cases were positive for HPV52. Among the samples, 1 case with an E2/E6 ratio >1 was purely episomal, 3 cases with an E2/E6 ratio of 0 were purely integrated, and 9 cases with an E2/E6 ratio of between 0 and 1 were a mixture of integrated and episomal. With the progression of cervical disease, the prevalence of the episomal type decreased gradually, and the prevalence of the integrated (episomal and integrated) forms increased. The pure integration of HPV52 occurred in chromosomes 2, 5 and 8. These results indicate that HPV52 integration into the host genome may be a key factor in cervical lesions. Thus, patients at high risk for cervical lesions may potentially be identified by screening for HPV52 infection and integration.

Proportion of transcriptionally active DNA virus integrants: a meta-analysis

Oncoviruses are collectively responsible for over 1,000,000 new cases of cancer per year; some can integrate into the host's chromosomes. The present work was aimed at assessing the proportion of transcriptionally active viral integrants through a systematic review of the scientific publications present on the MedLine database. From the articles screened, 628 viral integrants overall were retrieved, of which 530.84 were transcriptionally active (84.53%); among the clinical samples, 264 of 323 integrants were active (81.73%). The causes for the silencing were not addressed in the articles analyzed. These findings might highlight a possible risk factor for the insurgence of cancer since some oncovirus integrants could be reactivated by stimuli of disparate nature. Further studies should address such possibility.

Molecular approaches for HPV genotyping and HPV-DNA physical status

Persistent infection with high-risk human papillomavirus (HPV) genotypes is the leading cause of cervical cancer development. To this end several studies have focused on designing molecular assays for HPV genotyping, which are considered as the gold standard for the early diagnosis of HPV infection. Moreover, the tendency of HPV DNA to be integrated into the host chromosome is a determining event for cervical oncogenesis. Thus, the establishment of molecular techniques was promoted in order to investigate the physical status of the HPV DNA and the locus of viral insertion into the host chromosome. The molecular approaches that have been developed recently facilitate the collection of a wide spectrum of valuable information specific to each individual patient and therefore can significantly contribute to the establishment of a personalised prognosis, diagnosis and treatment of HPV-positive patients. The present review focuses on state of the art molecular assays for HPV detection and genotyping for intra-lesion analyses, it examines molecular approaches for the determination of HPV-DNA physical status and it discusses the criteria for selecting the most appropriate regions of viral DNA to be incorporated in HPV genotyping and in the determination of HPV-DNA physical status.

The negative conversion of high-risk human papillomavirus and its performance in surveillance of cervical cancer after treatment: a retrospective study

PURPOSE

To determine the negative conversion regularity of high-risk human papillomavirus (HR-HPV) and to evaluate the prognostic implications of HR-HPV testing in patients with cervical cancer after treatment.

METHODS

A retrospective post-treatment analysis of 173 patients with cervical cancer was performed from January 2011 to December 2012. Patients who had HR-HPV infection before treatment were included. Clinical and pathological characteristics, as well as follow-up information, were reviewed.

RESULTS

The negative conversion rate of HR-HPV reached 68.9 % within half a year and increased most rapidly within the first 2 years after treatment. Univariate and multivariate analyses suggested that the negative conversion rate of HR-HPV was significantly correlated with clinical stage, treatment regimens, and HR-HPV type (P < 0.05). In our analysis of 173 patients, we found that HR-HPV status was predictive of 3-year survival rate and disease recurrence (P < 0.05). Pelvic recurrence, but not distant metastasis, was influenced by HR-HPV status (P < 0.05). Through 2 × 2 table analysis, we found that HR-HPV was more sensitive (71.43 %) and specific (94.20 %) than cervical cytology (sensitivity 62.86 % and specificity 78.26 %).

CONCLUSIONS

The negative conversion rate of HR-HPV increased most rapidly within the first 2 years of cervical cancer surveillance. Persistent HPV infection was associated with a poor prognosis and had an impact on recurrence sites. Further large and multi-center prospective studies should be performed, but these results of this study suggested that HR-HPV monitoring is necessary to be used as a means of cervical cancer surveillance.

DNA Damage Reduces the Quality, but Not the Quantity of Human Papillomavirus 16 E1 and E2 DNA Replication

Human papillomaviruses (HPVs) are causative agents in almost all cervical carcinomas. HPVs are also causative agents in head and neck cancer, the cases of which are increasing rapidly. Viral replication activates the DNA damage response (DDR) pathway; associated proteins are recruited to replication foci, and this pathway may serve to allow for viral genome amplification. Likewise, HPV genome double-strand breaks (DSBs) could be produced during replication and could lead to linearization and viral integration. Many studies have shown that viral integration into the host genome results in unregulated expression of the viral oncogenes, E6 and E7, promoting HPV-induced carcinogenesis. Previously, we have demonstrated that DNA-damaging agents, such as etoposide, or knocking down viral replication partner proteins, such as topoisomerase II β binding protein I (TopBP1), does not reduce the level of DNA replication. Here, we investigated whether these treatments alter the quality of DNA replication by HPV16 E1 and E2. We confirm that knockdown of TopBP1 or treatment with etoposide does not reduce total levels of E1/E2-mediated DNA replication; however, the quality of replication is significantly reduced. The results demonstrate that E1 and E2 continue to replicate under genomically-stressed conditions and that this replication is mutagenic. This mutagenesis would promote the formation of substrates for integration of the viral genome into that of the host, a hallmark of cervical cancer.