Ménage à trois: an evolutionary interplay between human papillomavirus, a tumor, and a woman

The interplay between HPV, other Sexually Transmissible Infections and genital microbiome on cervical microenvironment (MicroCervixHPV study)

Background

The importance of Cervicovaginal Microbiota in protecting against infections (such as HPV) is already well established, namely through Lactobacillus spp., as well as the mechanism through which HPV leads to Cervical Neoplasia. However, it is not possible to classify HPV as a complete carcinogen. Thus, the importance of exploring Cervicovaginal dysbiosis with the intention of deciphering this interaction with HPV, takes on greater relevance. The main objectives of this study were: 1) Comparison of the MCV composition of women with or without HPV and women with ASCUS or LSIL; 2) Characterization of cytokines present in the vaginal microenvironment; 3) Evaluation of the blood count ratios as prognostic systemic inflammatory biomarkers; 4) Correlation between MCV, HPV serotypes and cytokines.

Methods

This was a retrospective, observational, multicenter, cross-sectional study. CVM analysis was performed by isolation RNA and sequencing on a NGS platform. Cytokine concentrations of CVM were obtained through Multiplex platform. Statistical analysis was performed in SPSS v 26.0. An α of 0.05 was considered statistically significant.

Results

Highlighting the core of the study, CVM types of CST I and CST IV were found to influence the emergence of cervical lesions. Neutrophil-to-Lymphocyte ratio was found to impact the prognosis of ASCUS. Within CVM, Lactobacillus prevent the growth of other CST IV species, while the latter express symbiotic relationships with each other and show affinity for specific HPV serotypes. At last, RANTES chemokine is significantly elevated in cervicovaginal infections.

Conclusion

The importance of using vaginal cytokine profiles and CVM is highlighted in the hypothesis of prevention of Cervical Neoplasia development, as well as in its use as a prognostic biomarker. Taken together, these insights are one step closer to personalized medicine.

Serum oxidative biomarkers associated with genital HPV infection and cervical lesions in women

Human papillomavirus (HPV) infection is a major cause of cervical cancer. Studies showed HPV carcinogenesis may be induced by oxidative stress affecting the host immune system. The objective of this study is to evaluate levels of four circulating oxidative stress biomarkers associated with the HPV infection, persistence, and cervical lesion status in women. The three serum biomarkers measuring oxidative damage to biomolecules (8-oxodG, 8-oxo-7,8-dihydro-2'-deoxyguanosine [8-oxodG] for DNA, 4-hydroxy-2-nonenal [4-HNE] for lipid, and protein carbonyl [PC] for protein) and one antioxidant (glutathione, GSH) collected from 38 women were evaluated. The PC levels were significantly higher for women with oncogenic HPV infection (p = 0.047) and persistence (p = 0.053) based on the unadjusted linear model. In particular, women with ≥3 oncogenic HPV types had a higher PC level than those without HPV infection (p = 0.041). Women with low-grade squamous intraepithelial lesions showed an elevated PC (p = 0.058). These trends remained similar after adjusting for age. The GSH levels were lower for women infected with ≥3 oncogenic HPV types based on age-adjusted results (p = 0.061). This study supported that serum PC was associated with HPV infection, persistence, and cervical lesions, so it can potentially be used to monitor HPV carcinogenesis. Further large-scale studies will be needed to confirm these findings.

HPV pathogenesis, various types of vaccines, safety concern, prophylactic and therapeutic applications to control cervical cancer, and future perspective

Over 98% of cervical cancers (CC) are caused by regular infections with "high risk" genotype of the human papilloma virus (HPV). However, this is not always the causative factor. Therefore, production of HPV vaccinations represents a significant chance to minimize the risk of CC. Phase III studies for a number of preventative HPV vaccines based on L1-virus-like particle (VLPs) have just been completed and the preliminary results are very convincing. However, there are a lot of practical concerns that need to be resolved before the use of these vaccinations. These vaccines were challenged with obvious queries such as protection time, subject receiving vaccines, time of vaccination, and how to include them into ongoing screening programs. Although these vaccines were 90% effective at preventing HPV infection as these offered only modest advantages for the removal of pre-existing infections. New advancements in the creation of therapeutic vaccinations have been explored for further improvement and post-vaccination surveillance. Therapeutic vaccines attempted to boost cell-mediated immunities and these are detrimental to the infected cell as opposed to neutralizing antibodies (different from prophylactic vaccines).

Analysis of the cervical microbiome in women from the German national cervical cancer screening program

PURPOSE

Cervical cancer (CC) is caused by a persistent high-risk human papillomavirus (hrHPV) infection. The cervico-vaginal microbiome may influence the development of (pre)cancer lesions. Aim of the study was (i) to evaluate the new CC screening program in Germany for the detection of high-grade CC precursor lesions, and (ii) to elucidate the role of the cervico-vaginal microbiome and its potential impact on cervical dysplasia.

METHODS

The microbiome of 310 patients referred to colposcopy was determined by amplicon sequencing and correlated with clinicopathological parameters.

RESULTS

Most patients were referred for colposcopy due to a positive hrHPV result in two consecutive years combined with a normal PAP smear. In 2.1% of these cases, a CIN III lesion was detected. There was a significant positive association between the PAP stage and Lactobacillus vaginalis colonization and between the severity of CC precursor lesions and Ureaplasma parvum.

CONCLUSION

In our cohort, the new cervical cancer screening program resulted in a low rate of additional CIN III detected. It is questionable whether these cases were only identified earlier with additional HPV testing before the appearance of cytological abnormalities, or the new screening program will truly increase the detection rate of CIN III in the long run. Colonization with U. parvum was associated with histological dysplastic lesions. Whether targeted therapy of this pathogen or optimization of the microbiome prevents dysplasia remains speculative.

Characterization of fecal microbiota in cervical cancer patients associated with tumor stage and prognosis

Cervical cancer (CC) is the fourth most frequent malignancy among women worldwide, and its prevention and treatment are evolving rapidly. The gut microbiota has been reported to play a crucial role both in the preservation of homeostasis and the development of cervical cancer. In this study, we collected fecal samples to investigate the microbial signatures in cervical cancer patients compared with healthy controls using 16S rRNA sequencing analysis and metagenomic next-generation sequencing (mNGS) testing. Our findings demonstrated a substantial difference in the gut microbiota composition of cervical cancer patients and healthy controls. The disease and stage were most significantly negatively correlated with Ruminococcus 2, which might be considered a potential clinically relevant biomarker. Functions of differential microbiomes were also analyzed, indicating significant differences in metabolisms and biosynthesis between the two groups. These findings demonstrate that patients with cervical cancer have certain species of gut microbiota that are exclusive to them and particular species have the potential to be used in the prognosis of cervical cancer.

Prognostic role of HPV integration status and molecular profile in advanced anal carcinoma: An ancillary study to the epitopes-HPV02 trial

Squamous Cell Carcinoma of the Anal canal (SCCA) is a rare disease associated with a Human Papillomavirus (HPV) infection in most cases, predominantly the HPV16 genotype. About 15% of SCCA are diagnosed in metastatic stage and some will relapse after initial chemoradiotherapy (CRT). Treatment of patients by Docetaxel, Cisplatin and 5-fluorouracil (DCF) has been recently shown to improve their complete remission and progression-free survival. The aim of this retrospective study was to explore the impact of HPV infection, HPV DNA integration, TERT promoter mutational status and somatic mutations of oncogenes on both progression-free (PFS) and overall survivals (OS) of patients treated by DCF. Samples obtained from 49 patients included in the Epitopes-HPV02 clinical trial, diagnosed with metastatic or non-resectable local recurrent SCCA treated by DCF, were used for analyses. Median PFS and OS were not associated with HPV status. Patients with episomal HPV had an improved PFS compared with SCCA patients with integrated HPV genome (p=0.07). TERT promoter mutations were rarely observed and did not specifically distribute in a subset of SCCA and did not impact DCF efficacy. Among the 42 genes investigated, few gene alterations were observed, and were in majority amplifications (68.4%), but none were significantly correlated to PFS. As no biomarker is significantly associated with patients’ survival, it prompts us to include every patient failing CRT or with metastatic disease in DCF strategy.

Microbiome and Cervical Cancer – A Review

Cervical cancer (CC) contributes to 6%-29% of all cancers in women. In India, 527,624 new cases of CC are added every year. India contributes to ¼ of deaths worldwide to CC it occurs often in women around the age of 30 yrs which is contributed by a specific kind of human papillomavirus causes long-term infection and inflammation (HPV) which result in morphological changes in the cells of cervix the region that connect vagina and uterus. Cervicovaginal microbiome is observed to be highly diverse among patients with CC where there is reduced number of Latobacillus spp that leads to dysbiosis and decrease in pH and eventually colonised by other anaerobic bacteria. The shift in community state types (CST) is highly associated with the Human Papillomavirus infection and its further progression to cervical dysplasia or CIN i.e. ‘Cervical intraepithelial neoplasia’ and malignant tumour of the cervix uteri. The purpose of this research is to figure out if there’s a link between the cervico-vaginal microbiota and gynaecological cancer and the review also focuses whether cervical microbiome signatures can predict the severity of infection leading to development of CC? Probiotics can be used as a potential alternative to balance the dysbiosis of the cervicovaginal environment. Hence the review summarizes the current knowledge and the interaction of different bacterial groups with Human Papilloma Virus infection and development of CC.

Association between Cervical Microbiota and HPV: Could This Be the Key to Complete Cervical Cancer Eradication?

Simple Summary

The microbiota can modulate immune responses and modify the physiology of the human organism, thereby increasing infective risks and a neoplastic predisposition. In this review, we focus on the composition of the cervical microbiota, to identify the risk of developing Cervical Intraepithelial Neoplasia and better understand the interaction between cervico-vaginal microbiota and human papillomavirus as a means of promoting the identification of new therapeutic strategies. In fact, no therapy for HPV is yet available. A better understanding of the cervical micro-environment could be a key element allowing complete viral clearance to be achieved in largely affected populations.

Abstract

The heterogeneity of the cervico-vaginal microbiota can be appreciated in various conditions, both pathological and non-pathological, and can vary according to biological and environmental factors. Attempts are still in course to define the interaction and role of the various factors that constitute this community of commensals in immune protection, inflammatory processes, and the onset of precancerous lesions of the cervical epithelium. Despite the many studies on the relationship between microbiota, immunity, and HPV-related cervical tumors, further aspects still need to be probed. In this review article, we will examine the principal characteristics of microorganisms commonly found in cervico-vaginal specimens (i) the factors that notoriously condition the diversity and composition of microbiota, (ii) the role that some families of organisms may play in the onset of HPV-dysplastic lesions and in neoplastic progression, and (iii) possible diagnostic-therapeutic approaches.

The Complex Interplay between Vaginal Microbiota, HPV Infection, and Immunological Microenvironment in Cervical Intraepithelial Neoplasia: A Literature Review

Background: in recent years, many studies were carried out to explore the role of vaginal microbiota in HPV infections and cervical intraepithelial neoplasia (CIN) progression. The aim of this study was to conduct a review of the literature to analyze the interaction between the vaginal microbiota, the CIN, and the immunological response. Methods: we performed a literature search, considering papers published between November 2015 and September 2021. Results: despite significant evidence suggesting a role of vaginal microbiota in the pathogenesis of HPV-related lesions, some studies still struggle to demonstrate this correlation. However, the vaginal microbiota of HPV-positive women shows an increased diversity, combined with a reduced relative abundance of Lactobacillus spp. and a higher pH. In cervical dysplasia progression, a strong association is found with new bacteria, and with the deregulation of pathways and hyperexpression of cytokines leading to chronic inflammation. Conclusions: in HPV progression, there is a strong correlation between potential biomarkers, such as Sneathia and Delftia found in community state types IV and II, and chronic inflammation with cytokine overexpression. Better analysis of these factors could be of use in the prevention of the progression of the disease and, eventually, in new therapeutic strategies.

Cervicovaginal DNA Virome Alterations Are Associated with Genital Inflammation and Microbiota Composition

While the link between the cervicovaginal bacterial microbiome, human papillomavirus (HPV) infection, and cervical cancer is recognized (P. Łaniewski, D. Barnes, A. Goulder, H. Cui, et al., Sci. Rep. 8:7593, 2018, http://dx.doi.org/10.1038/s41598-018-25879-7; A. Mitra, D. A. MacIntyre, Y. S. Lee, A. Smith, et al., Sci. Rep. 5:16865, 2015, http://dx.doi.org/10.1038/srep16865; A. Mitra, D. A. MacIntyre, J. R. Marchesi, Y. S. Lee, et al., Microbiome 4:58, 2016, http://dx.doi.org/10.1186/s40168-016-0203-0; J. Norenhag, J. Du, M. Olovsson, H. Verstraelen, et al., BJOG, 127:171-180, 2020, http://dx.doi.org/10.1111/1471-0528.15854; E. O. Dareng, B. Ma, A. O. Famooto, S. N. Adebamowo, et al., Epidemiol. Infect. 144:123-137, 2016, http://dx.doi.org/10.1017/S0950268815000965; A. Audirac-Chalifour, K. Torres-Poveda, M. Bahena-Roman, J. Tellez-Sosa et al., PLoS One 11:e0153274, 2016, http://dx.doi.org/10.1371/journal.pone.0153274; M. Di Paola, C. Sani, A. M. Clemente, A. Iossa, et al., Sci. Rep. 7:10200, 2017, http://dx.doi.org/10.1038/s41598-017-09842-6), the role of the cervicovaginal virome remains poorly understood. In this pilot study, we conducted metagenomic next-generation sequencing of cervicovaginal lavage specimens to investigate the relationship between the cervicovaginal DNA virome, bacterial microbiome, genital inflammation, and HPV infection. Specific virome alterations were associated with features of the local microenvironment related to HPV persistence and progression to cervical cancer. Cervicovaginal viromes clustered distinctly by genital inflammation state. Genital inflammation was associated with decreased virome richness and alpha diversity and an increased abundance of Anelloviridae species from the genus Alphatorquevirus. Lactobacillus bacteriophages were closely associated with increased Lactobacillus abundance, consistent with phage-host relationships. Interestingly, bacteria-bacteriophage transkingdom interactions were linked to genital inflammation and showed specific interactions with bacterial vaginosis-associated bacteria, including Gardnerella, Prevotella, and Sneathia. Taken together, our results reveal prominent virome interactions with features of the cervicovaginal microenvironment that are associated with HPV and cervical cancer. These findings expand our understanding of the cervicovaginal host-microbiome interactions in women's health. IMPORTANCE HPV infection is an established risk factor for cervical cancer. However, more broadly, the role of the cervicovaginal virome in cervical cancer progression is not well understood. Here, we identified cervicovaginal DNA virome alterations associated with local microenvironment factors (vaginal microbiota and genital inflammation) that influence HPV persistence and progression to cervical cancer. These findings indicate that the cervicovaginal virome plays an important role in women's health.

The Vaginal Microbiome: IV. The Role of Vaginal Microbiome in Reproduction and in Gynecologic Cancers

OBJECTIVE

This series of articles, titled The Vaginal Microbiome (VMB), written on behalf of the International Society for the Study of Vulvovaginal Disease, aims to summarize the recent findings and understanding of the vaginal bacterial microbiota, mainly regarding areas relevant to clinicians specializing in vulvovaginal disorders.

MATERIALS AND METHODS

A search of PubMed database was performed, using the search terms "vaginal microbiome" with "reproduction," "infertility," "fertility," "miscarriages," "pregnancy" "cervical cancer," "endometrial cancer," and "ovarian cancer." Full article texts were reviewed. Reference lists were screened for additional articles.

RESULTS

The fourth article of this series focuses on 2 distinct areas: the role of VMB in various aspects of human reproduction and, in sharp contrast, the association between the VMB and gynecologic malignancies. Several of the negative pregnancy outcomes have been associated with an altered VMB. Dysbiosis is remarkably linked with poor pregnancy outcomes from preconception to delivery. The associations between the microbiome and gynecologic cancers are described.

CONCLUSIONS

The development of the microbiome research, enabled by molecular-based techniques, has dramatically increased the detection of microorganisms and the understanding of bacterial communities that are relevant to maternal-fetal medicine in health and disease, as well as in gynecological malignancies. Proving causation in cancer is difficult because of the complex interactive nature of potential causative factors. Certain elements of the microbiota have been shown to provoke inflammatory reactions, whereas others produce anti-inflammatory reactions; this balance might be impaired with a change in microbial variety.

The exon junction complex core factor eIF4A3 is a key regulator of HPV16 gene expression

High-risk human papillomavirus (hrHPVs), particularly HPV16 and HPV18, are the etiologic factors of ano-genital cancers and some head and neck squamous cell carcinomas (HNSCCs). Viral E6 and E7 oncoproteins, controlled at both transcriptional and post-transcriptional levels, drive hrHPVs-induced carcinogenesis. In the present study, we investigated the implication of the DEAD-box helicase eukaryotic translation initiation factor 4A3 (eIF4A3,) an Exon Junction Complex factor, in the regulation of HPV16 gene expression. Our data revealed that the depletion of the factor eIF4A3 up-regulated E7 oncoprotein levels. We also showed that the inhibition of the nonsense-mediated RNA decay (NMD) pathway, resulted in the up-regulation of E7 at both RNA and protein levels. We therefore proposed that HPV16 transcripts might present different susceptibilities to NMD and that this pathway could play a key role in the levels of expression of these viral oncoproteins during the development of HPV-related cancers.

Hallmarks of cancer-the new testament

Diagnosis and treatment of disease demand a sound understanding of the underlying mechanisms, determining any Achilles' heel that can be targeted in effective therapies. Throughout history, this endeavour to decipher the origin and mechanism of transformation of a normal cell into cancer has led to various theories-from cancer as a curse to an understanding at the level of single-cell heterogeneity, meaning even among a single sub-type of cancer there are myriad molecular challenges to overcome. With increasing insight into cancer genetics and biology, the disease has become ever more complex to understand. The complexity of cancer as a disease was distilled into key traits by Hanahan and Weinberg in their seminal 'Hallmarks of Cancer' reviews. This lucid conceptualization of complex cancer biology is widely accepted and has helped advance cancer therapeutics by targeting the various hallmarks but, with the advancement in technologies, there is greater granularity in how we view cancer as a disease, and the additional understanding over the past decade requires us to revisit the hallmarks of cancer. Based on extensive study of the cancer research literature, we propose four novel hallmarks of cancer, namely, the ability of cells to regress from a specific specialized functional state, epigenetic changes that can affect gene expression, the role of microorganisms and neuronal signalling, to be included in the hallmark conceptualization along with evidence of various means to exploit them therapeutically.

The microbiome and gynaecological cancer development, prevention and therapy

The female reproductive tract (FRT), similar to other mucosal sites, harbours a site-specific microbiome, which has an essential role in maintaining health and homeostasis. In the majority of women of reproductive age, the microbiota of the lower FRT (vagina and cervix) microenvironment is dominated by Lactobacillus species, which benefit the host through symbiotic relationships. By contrast, the upper FRT (uterus, Fallopian tubes and ovaries) might be sterile in healthy individuals or contain a low-biomass microbiome with a diverse mixture of microorganisms. When dysbiosis occurs, altered immune and metabolic signalling can affect hallmarks of cancer, including chronic inflammation, epithelial barrier breach, changes in cellular proliferation and apoptosis, genome instability, angiogenesis and metabolic dysregulation. These pathophysiological changes might lead to gynaecological cancer. Emerging evidence shows that genital dysbiosis and/or specific bacteria might have an active role in the development and/or progression and metastasis of gynaecological malignancies, such as cervical, endometrial and ovarian cancers, through direct and indirect mechanisms, including modulation of oestrogen metabolism. Cancer therapies might also alter microbiota at sites throughout the body. Reciprocally, microbiota composition can influence the efficacy and toxic effects of cancer therapies, as well as quality of life following cancer treatment. Modulation of the microbiome via probiotics or microbiota transplant might prove useful in improving responsiveness to cancer treatment and quality of life. Elucidating these complex host-microbiome interactions, including the crosstalk between distal and local sites, will translate into interventions for prevention, therapeutic efficacy and toxic effects to enhance health outcomes for women with gynaecological cancers.

The Role of the Cervicovaginal Microbiome on the Genesis and as a Biomarker of Premalignant Cervical Intraepithelial Neoplasia and Invasive Cervical Cancer

The microbiome is able to modulate immune responses, alter the physiology of the human organism, and increase the risk of viral infections and development of diseases such as cancer. In this review, we address changes in the cervical microbiota as potential biomarkers to identify the risk of cervical intraepithelial neoplasia (CIN) development and invasive cervical cancer in the context of human papillomavirus (HPV) infection. Current approaches for clinical diagnostics and the manipulation of microbiota with the use of probiotics and through microbiota transplantation are also discussed.

Impact of modulation of telomerase and cancer stem-cell marker OCT4 axis in cervical cancer pathogenesis with underlying HPV16 infection

Lacunae exist in the molecular event(s) specificity associated with cervical cancer (CaCx) pathogenesis. The present study aimed to evaluate the significance of telomerase-cervical cancer stem cells (CSCs) modulation in CaCx pathogenesis with underlying HPV16 infection. The study included HPV16 positive cases only (N = 65) of the total enrolled cases from Northeast India. The analysis of viral load and the differential messenger RNA expression of E6, E7, hTERT, hTR, and cancer stem-cell markers was studied by real-time polymerase chain reaction. Further the protein and colocalization study for E6, hTERT, and oct4 was performed by immunofluorescence. The real-time polymerase chain reaction based analysis showed an upregulation of HPV16 viral oncoprotein E6 and E7, and telomerase component hTERT and hTR expression and their correlation in CaCx susceptibility and severity. The hTERT expression correlated with viral load; while the E6 and telomerase protein expression colocalized in the nucleus. The CSCs marker octamer-binding transcription factor 4 (OCT4) was significantly upregulated in CaCx cases, was associated with CaCx susceptibility and severity, and colocalized with E6 expression in the nucleus as revealed from the immunofluorescence studies. To conclude, the telomerase-OCT4 axis modulation holds key in HPV16 CaCx pathogenesis mediated by HPV16 E6 viral oncoprotein expression, and underlines its potential for therapeutic targeting.

Broad-Range Papillomavirus Transcriptome as a Biomarker of Papillomavirus-Associated Cervical High-Grade Cytology

Human papillomaviruses (HPVs) are responsible for >99% of cervical cancers. Molecular diagnostic tests based on the detection of viral DNA or RNA have low positive predictive values for the identification of cancer or precancerous lesions. Triage with the Papanicolaou test lacks sensitivity; and even when combined with molecular detection of high-risk HPV, this results in a significant number of unnecessary colposcopies. We have developed a broad-range detection test of HPV transcripts to take a snapshot of the transcriptome of 16 high-risk or putative high-risk HPVs in cervical lesions (HPVs 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66, 68, 73, and 82). The purpose of this novel molecular assay, named HPV RNA-Seq, is to detect and type HPV-positive samples and to determine a combination of HPV reads at certain specific viral spliced junctions that can better correlate with high-grade cytology, reflecting the presence of precancerous cells. In a proof-of-concept study conducted on 55 patients, starting from cervical smears, we have shown that HPV RNA-Seq can detect papillomaviruses with performances comparable to a widely used HPV reference molecular diagnostic kit; and a combination of the number of sequencing reads at specific early versus late HPV transcripts can be used as a marker of high-grade cytology, with encouraging diagnostic performances as a triage test.

Novel Approaches for Vaccination Against HPV-Induced Cancers

To date, more than 5 % of all cancers are as a result of human papillomavirus (HPV) infection, and this incidence is increasing. Early recognition of disease is associated with good survival, but late presentation results in devastating consequences. Prevention is better than cure, and there are now successful prophylactic vaccination programmes in place. We discuss these and the prospect of therapeutic vaccinations in the near future to address a growing need for improved therapeutic options.

Features of the cervicovaginal microenvironment drive cancer biomarker signatures in patients across cervical carcinogenesis

Persistent human papillomavirus (HPV) infection is the vital factor driving cervical carcinogenesis; however, other features of the local cervicovaginal microenvironment (CVM) may play a critical role in development of precancerous cervical dysplasia and progression to invasive cervical carcinoma (ICC). Here we investigated relationships between locally secreted cancer biomarkers and features of the local CVM to better understand the complex interplay between host, virus and vaginal microbiota (VMB). We enrolled women with ICC, high- and low-grade squamous intraepithelial lesions, as well as, HPV-positive and healthy HPV-negative controls. A broad range of cancer biomarkers was present in the local CVM and specifically elevated in ICC patients. The majority of cancer biomarkers were positively correlated to other biomarkers and linked to genital inflammation. Several cancer biomarkers were also negatively correlated to Lactobacillus abundance and positively correlated with abnormal vaginal pH. Finally, a hierarchical clustering analysis of cancer biomarkers and immune mediators revealed three patient clusters, which varied in levels of cancer biomarkers, genital inflammation, vaginal pH and VMB composition. Specific cancer biomarkers discriminated patients with features of the CVM, such as high genital inflammation, elevated vaginal pH and dysbiotic non-Lactobacillus-dominant VMB, that have been associated with HPV persistence, dysplasia and progression to ICC.

Transkingdom network reveals bacterial players associated with cervical cancer gene expression program

Cervical cancer is the fourth most common cancer in women worldwide with human papillomavirus (HPV) being the main cause the disease. Chromosomal amplifications have been identified as a source of upregulation for cervical cancer driver genes but cannot fully explain increased expression of immune genes in invasive carcinoma. Insight into additional factors that may tip the balance from immune tolerance of HPV to the elimination of the virus may lead to better diagnosis markers. We investigated whether microbiota affect molecular pathways in cervical carcinogenesis by performing microbiome analysis via sequencing 16S rRNA in tumor biopsies from 121 patients. While we detected a large number of intra-tumor taxa (289 operational taxonomic units (OTUs)), we focused on the 38 most abundantly represented microbes. To search for microbes and host genes potentially involved in the interaction, we reconstructed a transkingdom network by integrating a previously discovered cervical cancer gene expression network with our bacterial co-abundance network and employed bipartite betweenness centrality. The top ranked microbes were represented by the families Bacillaceae, Halobacteriaceae, and Prevotellaceae. While we could not define the first two families to the species level, Prevotellaceae was assigned to Prevotella bivia. By co-culturing a cervical cancer cell line with P. bivia, we confirmed that three out of the ten top predicted genes in the transkingdom network (lysosomal associated membrane protein 3 (LAMP3), STAT1, TAP1), all regulators of immunological pathways, were upregulated by this microorganism. Therefore, we propose that intra-tumor microbiota may contribute to cervical carcinogenesis through the induction of immune response drivers, including the well-known cancer gene LAMP3.

Linking cervicovaginal immune signatures, HPV and microbiota composition in cervical carcinogenesis in non-Hispanic and Hispanic women

While high-risk human papillomavirus (HPV) infection is a well-established risk factor for cervical cancer, there are likely other factors within the local microenvironment that contribute to cervical carcinogenesis. Here we investigated relationships between HPV, vaginal pH, vaginal microbiota (VMB) composition, level of genital immune mediators and severity of cervical neoplasm. We enrolled women with low- and high-grade cervical dysplasia (LGD, HGD), invasive cervical carcinoma (ICC), and healthy controls. HPV16, HPV45, HPV58, and HPV31 were the most prevalent in our cohort with HPV16 and HPV31 genotypes more prevalent in Hispanics. Vaginal pH was associated with ethnicity and severity of cervical neoplasm. Lactobacillus dominance decreased with the severity of cervical neoplasm, which correlated with elevated vaginal pH. Hispanic ethnicity was also associated with decreased Lactobacillus dominance. Furthermore, Sneathia was enriched in all precancerous groups, ICC, abnormal pH and Hispanic origin. Patients with ICC, but not LGD and HGD, exhibited increased genital inflammatory scores and elevated specific immune mediators. Notably, IL-36γ was significantly associated with ICC. Our study revealed local, host immune and microbial signatures associated with cervical carcinogenesis and provides an initial step to understanding the complex interplay between mucosal inflammation, HPV persistence and the VMB.

KF-finder: identification of key factors from host-microbial networks in cervical cancer

Background

The human body is colonized by a vast number of microbes. Microbiota can benefit many normal life processes, but can also cause many diseases by interfering the regular metabolism and immune system. Recent studies have demonstrated that the microbial community is closely associated with various types of cell carcinoma. The search for key factors, which also refer to cancer causing agents, can provide an important clue in understanding the regulatory mechanism of microbiota in uterine cervix cancer.

Results

In this paper, we investigated microbiota composition and gene expression data for 58 squamous and adenosquamous cell carcinoma. A host-microbial covariance network was constructed based on the 16s rRNA and gene expression data of the samples, which consists of 259 abundant microbes and 738 differentially expressed genes (DEGs). To search for risk factors from host-microbial networks, the method of bi-partite betweenness centrality (BpBC) was used to measure the risk of a given node to a certain biological process in hosts. A web-based tool KF-finder was developed, which can efficiently query and visualize the knowledge of microbiota and differentially expressed genes (DEGs) in the network.

Conclusions

Our results suggest that prevotellaceade, tissierellaceae and fusobacteriaceae are the most abundant microbes in cervical carcinoma, and the microbial community in cervical cancer is less diverse than that of any other boy sites in health. A set of key risk factors anaerococcus, hydrogenophilaceae, eubacterium, PSMB10, KCNIP1 and KRT13 have been identified, which are thought to be involved in the regulation of viral response, cell cycle and epithelial cell differentiation in cervical cancer. It can be concluded that permanent changes of microbiota composition could be a major force for chromosomal instability, which subsequently enables the effect of key risk factors in cancer. All our results described in this paper can be freely accessed from our website at http://www.nwpu-bioinformatics.com/KF-finder/.

Utility of high-throughput DNA sequencing in the study of the human papillomaviruses

The Papillomaviridae family is probably the most diverse group of viruses that affect vertebrates. The study of the relationship between infection by certain types of human papillomavirus (HPV) and the development of neoplastic epithelial lesions is of particular interest because of the high prevalence of HPV-related carcinomas in populations of developing countries. To understand the mechanisms of infection and their association with different clinical manifestations, molecular tools play an important role in the description of new types of HPV, the characterization of effector properties of the viral factors, the specific diagnosis and monitoring of HPV types, and the alteration patterns at genetic level in the host. Technological advances in the field of DNA sequencing have led to the development of different next-generation sequencing systems, allowing obtaining a large amount of data and broadening the applications to study viral diseases. In this review, we summarize the main approaches and their perspectives where the use of massively parallel sequencing has been proved as a useful tool in the research of the HPV infection.

Interplay between viruses and bacterial microbiota in cancer development

During the last few decades we have become accustomed to the idea that viruses can cause tumors. It is much less considered and discussed, however, that most people infected with oncoviruses will never develop cancer. Therefore, the genetic and environmental factors that tip the scales from clearance of viral infection to development of cancer are currently an area of active investigation. Microbiota has recently emerged as a potentially critical factor that would affect this balance by increasing or decreasing the ability of viral infection to promote carcinogenesis. In this review, we provide a model of microbiome contribution to the development of oncogenic viral infections and viral associated cancers, give examples of this process in human tumors, and describe the challenges that prevent progress in the field as well as their potential solutions.

Reprogramming energy metabolism and inducing angiogenesis: co-expression of monocarboxylate transporters with VEGF family members in cervical adenocarcinomas

Background

Deregulation of cellular energetic metabolism was recently pointed out as a hallmark of cancer cells. This deregulation involves a metabolic reprogramming that leads to a high production of lactate. Lactate efflux, besides contributing for the glycolytic flux, also acts in the extracellular matrix, contributing for cancer malignancy, by, among other effects, induction of angiogenesis. However, studies on the interplay between cancer metabolism and angiogenesis are scarce. Therefore, the aim of the present study was to evaluate the metabolic and vascular molecular profiles of cervical adenocarcinomas, their co-expression, and their relation to the clinical and pathological behavior.

Methods

The immunohistochemical expression of metabolism-related proteins (MCT1, MCT4, CD147, GLUT1 and CAIX) as well as VEGF family members (VEGF-A, VEGF-C, VEGF-D, VEGFR-1, VEGFR-2 and VEGFR-3) was assessed in a series of 232 cervical adenocarcinomas. The co-expression among proteins was assessed and the expression profiles were associated with patients’ clinicopathological parameters.

Results

Among the metabolism-related proteins, MCT4 and CAIX were the most frequently expressed in cervical adenocarcinomas while CD147 was the less frequently expressed protein. Overall, VEGF family members showed a strong and extended expression with VEGF-C and VEGFR-2 as the most frequently expressed and VEGFR-1 as the less expressed member. Co-expression of MCT isoforms with VEGF family members was demonstrated. Finally, MCT4 was associated with parametrial invasion and HPV18 infection, CD147 and GLUT1 with distant metastasis, CAIX with tumor size and HPV18 infection, and VEGFR-1 with local and lymphnode metastasis.

Conclusions

The results herein presented provide additional evidence for a crosstalk between deregulating cellular energetics and inducing angiogenesis. Also, the metabolic remodeling and angiogenic switch are relevant to cancer progression and aggressiveness in adenocarcinomas.

HPV16 Down-Regulates the Insulin-Like Growth Factor Binding Protein 2 to Promote Epithelial Invasion in Organotypic Cultures

Cervical cancer is a multi-stage disease caused by human papillomaviruses (HPV) infection of cervical epithelial cells, but the mechanisms regulating disease progression are not clearly defined. Using 3-dimensional organotypic cultures, we demonstrate that HPV16 E6 and E7 proteins alter the secretome of primary human keratinocytes resulting in local epithelial invasion. Mechanistically, absence of the IGF-binding protein 2 (IGFBP2) caused increases in IGFI/II signalling and through crosstalk with KGF/FGFR2b/AKT, cell invasion. Repression of IGFBP2 is mediated by histone deacetylation at the IGFBP2 promoter and was reversed by treatment with histone deacetylase (HDAC) inhibitors. Our in vitro findings were confirmed in 50 invasive cancers and 79 cervical intra-epithelial neoplastic lesions caused by HPV16 infection, where IGFBP2 levels were reduced with increasing disease severity. In summary, the loss of IGFBP2 is associated with progression of premalignant disease, and sensitises cells to pro-invasive IGF signalling, and together with stromal derived factors promotes epithelial invasion.

Viral carcinogenesis: factors inducing DNA damage and virus integration

Viruses are the causative agents of 10%-15% of human cancers worldwide. The most common outcome for virus-induced reprogramming is genomic instability, including accumulation of mutations, aberrations and DNA damage. Although each virus has its own specific mechanism for promoting carcinogenesis, the majority of DNA oncogenic viruses encode oncogenes that transform infected cells, frequently by targeting p53 and pRB. In addition, integration of viral DNA into the human genome can also play an important role in promoting tumor development for several viruses, including HBV and HPV. Because viral integration requires the breakage of both the viral and the host DNA, the integration rate is believed to be linked to the levels of DNA damage. DNA damage can be caused by both endogenous and exogenous factors, including inflammation induced by either the virus itself or by co-infections with other agents, environmental agents and other factors. Typically, cancer develops years to decades following the initial infection. A better understanding of virus-mediated carcinogenesis, the networking of pathways involved in transformation and the relevant risk factors, particularly in those cases where tumorigenesis proceeds by way of virus integration, will help to suggest prophylactic and therapeutic strategies to reduce the risk of virus-mediated cancer.