The vaginal microbiota, human papillomavirus infection and cervical intraepithelial neoplasia: what do we know and where are we going next?

Effects on Vaginal Microbiota Restoration and Cervical Epithelialization in Positive HPV Patients Undergoing Vaginal Treatment with Carboxy-Methyl-Beta-Glucan

Objective

Evaluate the effects of carboxy-methyl-beta-glucan on cervical epithelialization and on the vaginal microbiota in patients with HPV infection or low-grade cervical preneoplastic lesion (CIN 1).

Materials and Methods

Seven-hundred eighty-four women with positive HPV tests or diagnosed with CIN 1 were enrolled in a retrospective case-control study. All the recruited women performed, at baseline and after 6 months, Pap test, HPV test, evaluation of vaginal health according to the Amsel criteria, colposcopy, and punch biopsy. The study population was then divided into 2 groups in relation to the therapy performed during the follow-up period. Group A performed treatment with vaginal gel based on carboxy-methyl-beta-glucan (1 application/day for 20 days per month for 3 months). Group B was the control group.

Results

The patients of group A had a significant improvement in the ectopia pattern and a greater number of cases with metaplasia in the maturation phase with a significant increase in Lugol uptake. In the experimental group, a significant improvement in the pH indices, a negative Swift test and a resolution of the leucorrhoea were observed. A negative result of the 37.1% Pap test and the 39.9% HPV test (vs. 15.2% and 16.5%, respectively) were demonstrated in the treatment group with respect to the control group. A negativization of the colposcopic pictures was observed with a reduction in the amount of CIN 1 found higher in the treatment group.

Conclusions

Vaginal therapy based on carboxy-methyl-beta-glucan has been able to improve overall vaginal health; this effect seemed to positively impact the risk of persistence and progression of CIN.

The vaginal microbiota associates with the regression of untreated cervical intraepithelial neoplasia 2 lesions

Emerging evidence suggests associations between the vaginal microbiota (VMB) composition, human papillomavirus (HPV) infection, and cervical intraepithelial neoplasia (CIN); however, causal inference remains uncertain. Here, we use bacterial DNA sequencing from serially collected vaginal samples from a cohort of 87 adolescent and young women aged 16–26 years with histologically confirmed, untreated CIN2 lesions to determine whether VMB composition affects rates of regression over 24 months. We show that women with a Lactobacillus-dominant microbiome at baseline are more likely to have regressive disease at 12 months. Lactobacillus spp. depletion and presence of specific anaerobic taxa including Megasphaera, Prevotella timonensis and Gardnerella vaginalis are associated with CIN2 persistence and slower regression. These findings suggest that VMB composition may be a future useful biomarker in predicting disease outcome and tailoring surveillance, whilst it may offer rational targets for the development of new prevention and treatment strategies.

Persistent infection with human papillomavirus can lead to cervical intraepithelial neoplasia (CIN). Here, the authors profile the vaginal microbiota in a cohort of non-pregnant young women diagnosed with CIN2 and find that absence of Lactobacillusspp. and presence of a diverse population of strict anaerobes associates with a decreased regression of untreated CIN2 lesions.

The Role of CADM1 and MAL Promoter Methylation in Inflammation and Cervical Intraepithelial Neoplasia

Aims: This study investigated the presence of human papillomavirus (HPV) infection and the methylation status of the promoters of the cell adhesion molecule 1 (CADM1) gene and T lymphocyte maturation associated protein (MAL) gene in patients with cervicitis/inflammation and cervical intraepithelial neoplasia (CIN). Materials and Methods: Cervical specimens (n = 47) were collected from women with normal cervical cytology (n = 21) and those with cervical abnormalities (n = 26). The presence of HPV infection was confirmed by an HPV DNA test and an HPV mRNA test (Aptima HPV test). Methylation levels of the CADM1 and MAL promoters were evaluated by pyrosequencing. Results: Compared with the HPV DNA test, the Aptima HPV test improved specificity from 57% to 70% for the detection of inflammation and/or CIN type 1 (CIN1) or more advanced conditions (CIN1+). The methylation level of the CADM1 and MAL promoters was 1.5 times higher in inflammatory samples, compared with normal cervical cytology (p < 0.05). Conclusion: Selected 5'-C-phosphate-G-3' islands within the promoters of the CADM1 and MAL genes were differentially methylated in the inflammatory samples compared with the CIN samples. These results suggested that methylation likely occurred following tissue disruption, and the detection of persistent inflammation might be associated with a higher risk of lesion progression.

Association between Vaginal Infections and the Types and Viral Loads of Human Papillomavirus: A Clinical Study Based on 4,449 Cases of Gynecologic Outpatients

Objective

We here evaluated the association between human papillomavirus (HPV) infection and vaginal infections, including bacterial vaginosis (BV), trichomonas vaginalis (TV), and vulvovaginal candidiasis (VVC).

Methods

A total of 4,449 women were enrolled in this study and given gynecological examinations. HPV genotyping and viral load determination were performed using a real-time PCR. Vaginal infections were diagnosed using wet mounts of vaginal secretions, gram-stained vaginal secretion smears, and chemical enzyme kits.

Results

In this study, the overall HPV-positive rate was 25.06%, and vaginal infection tended to occur in women with HPV infection (P < 0.05). HPV infection tended to occur in BV- and TV-positive women (P < 0.05) and not in women with microecological disorders, intermediate type BV, VVC, or coinfection (P > 0.05). The most common genotypes were HPV58 and HPV53 in women with normal vaginal microecology and HPV16 and HPV52 in the women suffering from vaginal infection. The viral loads among groups for HPV16 and HPV52 showed no statistically significant differences (P=0.940; P=0.167).

Conclusions

Our study revealed that BV and TV are associated with HPV infection, especially high-risk HPV infection, while VVC has no association with HPV infection. Further studies are needed to explore the detailed mechanism.

Use of the dapivirine vaginal ring and effect on cervical cytology abnormalities

OBJECTIVE

We aimed to determine if the dapivirine vaginal ring and the ring device alone (flexible silicone matrix polymer) was associated with the development of cervical cytology abnormalities.

DESIGN

Secondary analysis comparing cervical cytology results between two randomized controlled microbicide trials (MTN-020/ASPIRE and MTN-003/VOICE).

METHODS

Data from ASPIRE, a phase III, placebo-controlled trial of the dapivirine vaginal ring, were used in this analysis. Cervical cytology smears were evaluated at baseline and at the final visit with product use. We compared cytology results between women randomized to dapivirine versus placebo vaginal ring. We further assessed for the effect of the vaginal ring device on cervical cytology by comparing results with data from the oral placebo arm of VOICE, a prior HIV-1 prevention trial conducted in a similar population.

RESULTS

Cervical cytology results for 2394 women from ASPIRE (1197 per study arm) were used in this analysis; median time between baseline and final visit with product use was 22.1 months. Cytology smear findings were comparable between dapivirine and placebo vaginal ring arms: at final visit, normal: 90.6 versus 91.5%, ASC-US//LSIL: 7.8 versus 7.4%, ASC-H/HSIL/AGC/AGC-favor neoplastic: 1.7 versus 1.1%, P = 0.44. Cytology data from VOICE had findings (normal: 87.8%, ASC-US/LSIL: 9.8%, ASC-H/HSIL/AGC/AGC-favor neoplastic: 2.4%) comparable with that of both dapivirine (P = 0.93) and placebo vaginal ring arms (P = 0.24).

CONCLUSION

These findings indicate that neither use of the dapivirine vaginal ring nor the vaginal ring device alone, over a period of 2 years, is associated with development of cervical cytology abnormalities that could lead to precancerous or cancerous lesions.

Asymptomatic Bacterial Vaginosis Is Associated With Depletion of Mature Superficial Cells Shed From the Vaginal Epithelium

Previous studies have described bacterial vaginosis (BV) as associated with increased cell-shedding from the cervicovaginal epithelium. Cell-shedding in excess of cell-proliferation is thought to decrease epithelial barrier function and increase susceptibility to infection. This study evaluated the number of shed cells in mid-vaginal smears from women with a diagnosis of symptomatic BV (sBV, n = 17), asymptomatic BV (aBV, n = 71), or no BV (n = 104) by Amsel criteria. The sBV smears contained significantly more shed cells (median 158/100X field) than no BV smears (median 91/100X field), p = 7.2e−9. However, we observed that aBV smears contained significantly fewer shed cells (median 35/100X field) than no BV smears, p = 22.0e−16. The sizes of cell-aggregates (cells shed in sometimes multilayered sections with intact cell-cell attachments) followed the same pattern. Cell-aggregates in sBV smears were significantly larger (median ~220,000 μm²) than those in no BV smears (median ~50,000 μm²), p = 1.8e−6, but cell-aggregates in aBV smears were significantly smaller (median ~7,000 μm²) than those in no BV smears, p = 0.0028. We also compared the superficial cell index (SCI), a measure of cervicovaginal epithelial cell maturity, in no BV and aBV smears with relatively low numbers of shed cells (≤50/100X field). The SCI of no BV smears was significantly higher (median 0.86) than that of aBV smears (median 0.35), p = 4.3e−98, suggesting a depletion of mature cells with exposure and shedding of underlying immature cells in aBV with low number of shed cells. These results indicate that aBV may contribute disproportionately to the increased susceptibility to reproductive tract infections associated with BV. Our findings remained true when considering only those smears in which the microbiota comprised a diverse set of strict and facultative anaerobic bacteria [Community State Type IV (n = 162)], thus excluding those dominated by Lactobacillus spp. This is consistent with our developing hypothesis that high-shedding sBV and low-shedding aBV could be temporally separated phases of the same condition, rather than two separate forms of BV. These findings might inform future work on clinical management of symptomatic and asymptomatic bacterial vaginosis.

Bacterial vaginosis and surgical site infections

Bacterial vaginosis is the most common cause of abnormal vaginal discharge or malodor, affecting up to one third of US women. Most women with bacterial vaginosis are unaware of the infection, making it difficult to diagnose in the absence of a microscopic examination of vaginal discharge or using point-of-care testing. Untreated bacterial vaginosis elevates the risk of postoperative surgical infections in women undergoing obstetric and gynecological procedures. Treatment with antimicrobial agents that target bacterial vaginosis has been shown to reduce the rate of postoperative infections following hysterectomy and surgical abortions. Furthermore, in a cost-comparison model, screening for and treatment of bacterial vaginosis prior to hysterectomy was shown to be superior to no screening in terms of infection rates and cost. The bacterial vaginosis diagnostic criteria are simple and screening tests are inexpensive; bacterial vaginosis screening is a relatively fast process in patients who present for preoperative appointments. Treatment options approved by the Food and Drug Administration include metronidazole, clindamycin, tinidazole, and secnidazole. Given the prevalence of bacterial vaginosis and the risks associated with operating on a woman with untreated bacterial vaginosis, women undergoing hysterectomy, surgical abortion, and potentially cesarean delivery should be screened for bacterial vaginosis, and those who screen positive should be treated with an appropriate antimicrobial agent.

How the Cervical Microbiota Contributes to Cervical Cancer Risk in Sub-Saharan Africa

Despite ongoing efforts, sub-Saharan Africa faces a higher cervical cancer burden than anywhere else in the world. Besides HPV infection, definitive factors of cervical cancer are still unclear. Particular states of the cervicovaginal microbiota and viral infections are associated with increased cervical cancer risk. Notably, HIV infection, which is prevalent in sub-Saharan Africa, greatly increases risk of cervicovaginal dysbiosis and cervical cancer. To better understand and address cervical cancer in sub-Saharan Africa, a better knowledge of the regional cervicovaginal microbiome is required This review establishes current knowledge of HPV, HIV, cervicovaginal infections, and the cervicovaginal microbiota in sub-Saharan Africa. Because population statistics are not available for the region, estimates are derived from smaller cohort studies. Microbiota associated with cervical inflammation have been found to be especially prevalent in sub-Saharan Africa, and to associate with increased cervical cancer risk. In addition to high prevalence and diversity of HIV and HPV, intracellular bacterial infections such as Chlamydia, Gonorrhea, and Mycoplasma hominis are much more common than in regions with a low burden of cervical cancer. This suggests the prevalence of cervical cancer in sub-Saharan Africa may be partially attributed to increased cervical inflammation resulting from higher likelihood of cervical infection and/or microbial dysbiosis.

Research of the potential biomarkers in vaginal microbiome for persistent high-risk human papillomavirus infection

Background

Vaginal dysbiosis may paly role in increased risk of human papillomavirus (HPV) infection. This study aims to explore potential vaginal microbiome biomarkers, to predict persistent high-risk HPV (HR-HPV) infection and cervical intraepithelial neoplasia (CIN) 2+, and to find novel treatment targets for HPV infection.

Methods

A total of 329 women aged 20-69 were enrolled in this study, including 59 with cervical persistent HPV infection irrespective of cytology status (group A), 139 with incident HPV infection (group B), and 131 without HPV infection (group C). Vaginal microbiome composition was determined by sequencing of barcoded 16S rDNA gene fragments (V4) on Illumina HiSeq2500.

Results

In genus level, the relative abundance of Prevotella, Porphyromonas and Enterococcus were significantly the highest in group A, while Bacteroides was the lowest in group A. In species level, we found the relative abundance of Prevotella bivia, Enterococcus durans and Porphyromonas uenonis were the highest in group A while Lactobacillus iners was significantly under-represented in group A than the other two, and Prevotella disiens was over-represented in group C than the other two groups.

Conclusions

A predominance of Prevotella bivia, Enterococcus durans and Porphyromonas uenonis with a concomitant paucity of Lactobacillus iners and Prevotella disiens may relate to HPV persistent infection. Furthermore, the relative abundance of Prevotella bivia being over 0.05554% with Prevotella disiens being under 0.02196% may be a good predictor for appearance CIN2+ for those diagnosed with the other 12 types of HR-HPV persistent infection but normal ThinPrep cytology test (TCT) testing. The exact molecular mechanism of the vaginal microbiome in the course of persistent HR-HPV infection and cervical neoplasia should be further explored. Future research should include intervention of vaginal microbiome composition to reverse the course of HR-HPV infection and the natural history of cervical neoplasia.

Defining the relationship between vaginal and urinary microbiomes

BACKGROUND

Although the vaginal and urinary microbiomes have been increasingly well-characterized in health and disease, few have described the relationship between these neighboring environments. Elucidating this relationship has implications for understanding how manipulation of the vaginal microbiome may affect the urinary microbiome and treatment of common urinary conditions.

OBJECTIVE

To describe the relationship between urinary and vaginal microbiomes using 16S rRNA gene sequencing. We hypothesized that the composition of the urinary and vaginal microbiomes would be significantly associated, with similarities in predominant taxa.

STUDY DESIGN

This multicenter study collected vaginal swabs and catheterized urine samples from 186 women with mixed urinary incontinence enrolled in a parent study and 84 similarly aged controls. Investigators decided a priori that if vaginal and/or urinary microbiomes differed between continent and incontinent women, the groups would be analyzed separately; if similar, samples from continent and incontinent women would be pooled and analyzed together. A central laboratory sequenced variable regions 1-3 (v1-3) and characterized bacteria to the genus level. Operational taxonomic unit abundance was described for paired vaginal and urine samples. Pearson's correlation characterized the relationship between individual operational taxonomic units of paired samples. Canonical correlation analysis evaluated the association between clinical variables (including mixed urinary incontinence and control status) and vaginal and urinary operational taxonomic units, using the Canonical correlation analysis function in the Vegan package (R version 3.5). Linear discriminant analysis effect size was used to find taxa that discriminated between vaginal and urinary samples.

RESULTS

Urinary and vaginal samples were collected from 212 women (mean age 53±11 years) and results from 197 paired samples were available for analysis. As operational taxonomic units in mixed urinary incontinence and control samples were related in canonical correlation analysis and since taxa did not discriminate between mixed urinary incontinence or controls in either vagina or urine, mixed urinary incontinence and control samples were pooled for further analysis. Canonical correlation analysis of vaginal and urinary samples indicated that that 60 of the 100 most abundant operational taxonomic units in the samples largely overlapped. Lactobacillus was the most abundant genus in both urine and vagina (contributing on average 53% to an individual's urine sample and 64% to an individual's vaginal sample) (Pearson correlation r=0.53). Although less abundant than Lactobacillus, other bacteria with high Pearson correlation coefficients also commonly found in vagina and urine included: Gardnerella (r=0.70), Prevotella (r=0.64), and Ureaplasma (r=0.50). Linear discriminant analysis effect size analysis identified Tepidimonas and Flavobacterium as bacteria that distinguished the urinary environment for both mixed urinary incontinence and controls as these bacteria were absent in the vagina (Tepidimonas effect size 2.38, P<.001, Flavobacterium effect size 2.15, P<.001). Although Lactobacillus was the most abundant bacteria in both urine and vagina, it was more abundant in the vagina (linear discriminant analysis effect size effect size 2.72, P<.001).

CONCLUSION

Significant associations between vaginal and urinary microbiomes were demonstrated, with Lactobacillus being predominant in both urine and vagina. Abundance of other bacteria also correlated highly between the vagina and urine. This inter-relatedness has implications for studying manipulation of the urogenital microbiome in treating conditions such as urgency urinary incontinence and urinary tract infections.

Mechanistic insights into the action of probiotics against bacterial vaginosis and its mediated preterm birth: An overview

The human body is a reservoir of numerous micro-creatures; whose role is substantial and indispensable in the overall development of human beings. The advances in omic approaches have offered powerful means to decipher the core microbiome and metabolome diversities in a specific organ system. The establishment of lactobacilli in the female reproductive tract is thought to be a paramount prerequisite that maintains homeostatic conditions for a sustainable and healthy pregnancy. Nevertheless, a plethora of such Lactobacillus strains of vaginal source revealed probiotic phenotypes. The plummeting in the occurrence of lactobacilli in the vaginal ecosystem is associated with several adverse pregnancy outcomes (APOs). One such pathological condition is "Bacterial Vaginosis" (BV), a pathogen dominated gynecological threat. In this scenario, the ascending traffic of notorious Gram-negative/variable BV pathogens to the uterus is one of the proposed pathways that give rise to inflammation-related APOs like preterm birth. Since antibiotic resistance is aggravating among urogenital pathogens, the probiotics intervention remains one of the alternative biotherapeutic strategies to overcome BV and its associated APOs. Perhaps, the increased inclination towards the safer and natural biotherapeutic strategies rather than pharmaceutical drugs for maintaining gestational and reproductive health resulted in the use of probiotics in pregnancy diets. In this context, the current review is an attempt to highlight the microbiome and metabolites signatures of BV and non-BV vaginal ecosystem, inflammation or infection-related preterm birth, host-microbial interactions, role and effectiveness of probiotics to fight against aforesaid diseased conditions.

A population-based study of age-related associations between vaginal pH and the development of cervical intraepithelial neoplasia

The association between vaginal pH and the risk of cervical intraepithelial neoplasia (CIN) is unclear. We evaluated the dose‐response relationship between vaginal pH and CIN risk, as well as the combined influence of vaginal pH and high‐risk human papillomavirus (hrHPV) on the risk of CIN and the mediation effects of hrHPV infection on vaginal pH level and the development of CIN. We investigated 2304 women in Shanxi, China. The dose‐response relationship between vaginal pH and CIN risk was assessed using categoric and spline analyses. We established interaction and mediation models to determine the correlation between pH and hrHPV in the development of CIN. After adjusting covariates, a positive association was observed between hrHPV infection and the development of CIN [OR (95% CI) = 4.75 (3.52‐6.40) for CIN2+; OR (95% CI) = 7.30 (4.10‐13.00) for CIN3+], while a negative correlation was showed between vaginal pH level and CIN3+ [OR (95% CI) = 1.04 (0.59‐1.84); high vs low: OR (95% CI) = 0.32 (0.15‐0.69), P = .002]. The highest risk of CIN (5.24 of CIN2+ and 5.80 of CIN3+) were observed when hrHPV infection was combined with middle vaginal pH (4.6‐5.0). A significant mediation effect of hrHPV infection was observed in the association between vaginal pH level with CIN2+ (P = .002) and CIN3+ (P = .004). In conclusion, abnormal vaginal pH significantly induced the risk of high‐stage CIN in Chinese women infected with hrHPV. Therefore, maintaining normal vaginal pH levels may reduce the risk of CIN.

Correlation between the diversity of vaginal microbiota and the risk of high-risk human papillomavirus infection

OBJECTIVES

Since other genital infections enhance HIV susceptibility by inducing inflammation and evidence suggests that the vaginal microbiome plays a functional role in the persistence or regression of high-risk human papillomavirus (HPV) infections, we investigated the relationship between the composition of the vaginal microbiota and the risk of high-risk HPV infection.

METHODS

The study included 151 healthy women (65 HPV-positive and 86 HPV-negative) aged 20-65 at enrollment. Total genome DNA from samples was extracted using the hexadecyltrimethylammonium bromide (CTAB) CTAB method. The vaginal microbiota composition was determined by sequencing barcoded 16S rDNA gene fragments (V4) on Illumina HiSeq2500.

RESULTS

Of the 30 most abundant bacteria at the genus level, we found only six bacteria with a statistical difference between HPV-positive and HPV-negative women: Bacteroides, Acinetobacter, Faecalibacterium, Streptococcus, Finegoldia, and Moryella. Lactobacillus was the predominant genus and was detected in all women, but there was no significant difference between the two groups for L. iners, L. jensenii, and L. gasseri. Furthermore, we found 26 types of bacteria with a statistical difference at the species level between the two groups. Anaerobic bacteria such as Bacteroides plebeius, Acinetobacter lwoffii, and Prevotella buccae were found significantly more frequently in HPV-positive women, which is the most important finding of our study.

CONCLUSION

Our findings suggest a possible role for the composition of the vaginal microbiota as a modifier of high-risk HPV infection, and specific microbiota species may serve as sensors for changes in the cervical microenvironment associated with high-risk HPV infection. The exact molecular mechanism of the vaginal microbiota in the course of high-risk HPV infection and cervical neoplasia should be further explored. Future research should include intervention in the composition of the vaginal microbiota to reverse the course of high-risk HPV infection and the natural history of cervical neoplasia.

Association between Vaginal Micro-environment Disorder and Cervical Intraepithelial Neoplasia in a Community Based Population in China

There are other factors that contribute to cervical carcinogenesis except HPV infection. This study aimed to investigate the association between vaginal micro-environment factors, including H₂O₂, vaginal PH value, vagina cleanness, β-glucuronidase, coagulase, neuraminidase and leukocyte esterase and cervical intraeipithelial neoplasia (CIN). In total 1019 participants, including 623 normal cervical (NC) women, 303 patients with low-grade cervical intraepithelial neoplasia (CIN1) and 93 patients with high-grade cervical intraepithelial neoplasia (CIN2/3), were enrolled into the study. HPV genotyping was detected by flow-through hybridization and gene chip. Vaginal H₂O₂, β-glucuronidase, coagulase, neuraminidase and leukocyte esterase were detected by Aerobic Vaginitis (AV) / Bacterial Vaginal Disease (BV) Five Joint Test Kit. Vaginal PH was measured on the glass slide after microscopy, using color strips with a PH range of 3.8-5.4. Vagina cleanness was determined according to the National Clinical Laboratory Practice Guideline. χ²test and Logistic regression were operated using SPSS 22.0 software. Our results showed that HPV16 infection rate and the abnormal rates of H₂O₂, PH, vagina cleanness, β-glucuronidase or neuraminidase increased gradually along with the severity of CIN (P<0.05). Abnormities of H₂O₂, cleanness, β-glucuronidase and neuraminidase were risk factors for CIN regardless of HPV16 infection, furthermore, abnormities of PH value, leukocyte esterase could also increase the risk of CIN in HPV16 positive group. In addition, women with abnormal vaginal micro-environment factors in HPV16 positive group had a significantly higher risk of developing CIN than HPV16 negative group. The results from generalized multifactor dimensionality reduction (GMDR) model showed that there was interaction effect with abnormities of vagina cleanness, H₂O₂, β-glucuronidase and neuraminidase on CIN2/3 in HPV16 negative group, while, there was interaction effect with abnormities of vagina cleanness, β-glucuronidase and neuraminidase on CIN1 and with abnormities of vagina cleanness, PH, H₂O₂, β-glucuronidase, neuraminidase and leukocyte esterase on CIN2/3 in HPV16 positive group. Our results suggested that vaginal micro-environment disorder could increase the risk of CIN, especially, the abnormality of H₂O₂, cleanness, β-glucuronidase and neuraminidase. There were interaction effects with abnormities of H₂O₂, vagina cleanness, β-glucuronidase and neuraminidase on CIN whether HPV16 was infected or not.

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.

Current status of therapeutic HPV vaccines

The accumulating successes of immune-based treatments for solid tumors have prompted an explosion of cancer clinical trials testing strategies to elicit tumor-specific immune effector responses, either alone, in combination with immune checkpoint blockade, or with conventional cancer treatment modalities. However, across the board, clinical responses have been achieved in only a limited subset of cancer patients, underscoring a critical need to identify mechanisms and biomarkers of response, as well as mechanisms of resistance to therapy. Cancers caused by human papillomavirus (HPV) are driven by two viral oncoproteins, E6 and E7, both of which are functionally required for cellular transformation, thereby providing non-'self', tumor-specific antigenic targets. Immune responses that are specific for either or both of these oncoproteins can be used to follow the magnitude and kinetics of immune responses to therapeutic interventions. Moreover, identifying neoantigens is not a concern in early-stage disease - since HPV cancers are driven by HPV oncoproteins, the somatic mutational load in early disease is low, particularly in comparison to non-HPV-related squamous cancers arising in the same organ site [1,2]. Cancers caused by HPV are a model clinical setting in which to test principles of immunotherapies, and to discover mechanisms of interactions between tumors and their attendant immune milieu. In this review, we will use examples of insights gained from studies of HPV disease to illustrate major themes of immune-based therapeutic strategies.

Simultaneous detection and comprehensive analysis of HPV and microbiome status of a cervical liquid-based cytology sample using Nanopore MinION sequencing

Human papillomavirus (HPV) is a major pathogen that causes cervical cancer and many other related diseases. HPV infection related cervical microbiome could be an induce factor of cervical cancer. However, it is uncommon to find a single test on the market that can simultaneously provide information on both HPV and the microbiome. Herein, a novel method was developed in this study to simultaneously detect HPV infection and microbiota composition promptly and accurately. It provides a new and simple way to detect vaginal pathogen situation and also provide valuable information for clinical diagnose. This approach combined multiplex PCR, which targeted both HPV16 E6E7 and full-length 16S rRNA, and Nanopore sequencing to generate enough information to understand the vagina condition of patients. One HPV positive liquid-based cytology (LBC) sample was sequenced and analyzed. After comparing with Illumina sequencing, the results from Nanopore showed a similar microbiome composition. An instant sequencing evaluation showed that 15 min sequencing is enough to identify the top 10 most abundant bacteria. Moreover, two HPV integration sites were identified and verified by Sanger sequencing. This approach has many potential applications in pathogen detection and can potentially aid in providing a more rapid clinical diagnosis.

Characterization of vaginal microbiota in women with preterm labor with intra-amniotic inflammation

This study aims to investigate the relation between vaginal microbiota and exposition to intra-amniotic inflammation (IAI). We conducted a prospective cohort study in women with preterm labor <34 weeks who had undergone amniocentesis to rule out IAI. Vaginal samples were collected after amniocentesis. Women with IAI included those with positive amniotic fluid (AF) for a microorganism identified by specific culture media and Sanger sequencing 16S ribosomal RNA gene and/or high AF interleukin (IL)-6 levels. Vaginal microbiota was characterized by 16S ribosomal RNA gene amplicon sequencing. Specific quantitative PCR targeted to Lactobacillus spp. was also performed. Regression models were used to evaluate associations between vaginal microbiota and exposition to IAI. Concerning our results, 64 women were included. We observed an inverse association between AF IL-6 levels and load of Lactobacillus spp. Depletion in Lactobacillus spp. load was significantly associated with an early gestational age at delivery and a short latency to delivery. Microbial-diversity was found to be a risk factor for the subsequent occurrence of clinical chorioamnionitis. To the contrary, higher Lactobacillus spp. load had a protective role. In conclusion, the study identifies reduced bacterial load of Lactobacillus spp. in women exposed to IAI and found microbial-diversity and Lactobacillus spp. depletion to be associated with a worse perinatal outcome.

High risk human papilloma virus (HPV) common among a cohort of women with female genital mutilation

Background

Nigeria accounts for 25% of cases of Female genital mutilation (FGM) worldwide, with increased incidence of cervical cancer.

Objective

This study was aimed at evaluating the relationship between FGM and HPV in a locality with high prevalence of FGM.

Methods

Papanicolaou test, DNA hybridization using Polymerase Chain Reaction (PCR), and flow-through hybridization was done to determine the genotypic variants of the HPV. Physical examination and questionnaires were also used to ascertain presence of FGM.

Results

FGM was found among 98(49%) subjects, while 23(11.5%) had one or more genotype of HPV. Majority of the cases of HPV (78.3%) occurred in FGM subjects. Seventeen Genotypes of HPV were found among subjects with FGM consisting of 11 high risk (16, 18, 31, 33, 35, 39, 52, 56, 73, 81, 82) and 6 low risk (43, 44, 6, 26, 84, 70). A correlation (p value = 0.0052 at 95% CI) was found between FGM and HPV prevalence with a positive result for post hoc analysis. Results show the first reported case of quintuple HPV infection in a single subject in Nigeria.

Conclusion

FGM needs to be halted as it has no known health benefit yet may increase the risk for cervical cancer.

The vaginal metabolome and microbiota of cervical HPV-positive and HPV-negative women: a cross-sectional analysis

OBJECTIVE

Characterise the vaginal metabolome of cervical HPV-infected and uninfected women.

DESIGN

Cross-sectional.

SETTING

The Center for Health Behavior Research at the University of Maryland School of Public Health.

SAMPLE

Thirty-nine participants, 13 categorised as HPV-negative and 26 as HPV-positive (any genotype; HPV⁺ ), 14 of whom were positive with at least one high-risk HPV strain (hrHPV).

METHOD

Self-collected mid-vaginal swabs were profiled for bacterial composition by 16S rRNA gene amplicon sequencing, metabolites by both gas and liquid chromatography mass spectrometry, and 37 types of HPV DNA.

MAIN OUTCOME MEASURES

Metabolite abundances.

RESULTS

Vaginal microbiota clustered into Community State Type (CST) I (Lactobacillus crispatus-dominated), CST III (Lactobacillus iners-dominated), and CST IV (low-Lactobacillus, 'molecular-BV'). HPV⁺ women had higher biogenic amine and phospholipid concentrations compared with HPV^- women after adjustment for CST and cigarette smoking. Metabolomic profiles of HPV⁺ and HPV^- women differed in strata of CST. In CST III, there were higher concentrations of biogenic amines and glycogen-related metabolites in HPV⁺ women than in HPV^- women. In CST IV, there were lower concentrations of glutathione, glycogen, and phospholipid-related metabolites in HPV⁺ participants than in HPV^- participants. Across all CSTs, women with hrHPV strains had lower concentrations of amino acids, lipids, and peptides compared with women who had only low-risk HPV (lrHPV).

CONCLUSIONS

The vaginal metabolome of HPV⁺ women differed from HPV^- women in terms of several metabolites, including biogenic amines, glutathione, and lipid-related metabolites. If the temporal relation between increased levels of reduced glutathione and oxidised glutathione and HPV incidence/persistence is confirmed in future studies, anti-oxidant therapies may be considered as a non-surgical HPV control intervention.

TWEETABLE ABSTRACT

Metabolomics study: Vaginal microenvironment of HPV⁺ women may be informative for non-surgical interventions.

Potential role of microbiome in oncogenesis, outcome prediction and therapeutic targeting for head and neck cancer

In the last decade, human microbiome research is rapidly growing involving several fields of clinical medicine and population health. Although the microbiome seems to be linked to all sorts of diseases, cancer has the biggest potential to be investigated. Following the publication of the National Institute of Health - Human Microbiome Project (NIH-HMP), the link between Head and Neck Cancer (HNC) and microbiome seems to be a fast-moving field in research area. However, robust evidence-based literature is still quite scarce. Nevertheless the relationship between oral microbiome and HNC could have important consequences for prevention and early detection of this type of tumors. The aims of the present review are: (i) to discuss current pre-clinical evidence of a role of oral microbiome in HNC; (ii) to report recent developments in understanding the human microbiome's relationship with HNC oncogenesis; (iii) to explore the issue of treatment response and treatment toxicity; (iv) to describe the role of microbiota as potentially modifiable factor suitable for targeting by therapeutics. Further studies are needed to better establish the causal relationship between oral microbiome and HNC oncogenesis. Future trials should continue to explore oral microbiome in order to build the scientific and clinical rationale of HNC preventative and ameliorate treatment outcome.

A meta-analysis of the relationship between vaginal microecology, human papillomavirus infection and cervical intraepithelial neoplasia

Microecology is an emerging discipline in recent years. The female reproductive tract is an important microecological region, and its microecological environment can directly affect women's cervical health. This meta-analysis aimed to analyze the effects of vaginal microecology on Human papillomavirus (HPV) infection and cervical intraepithelial neoplasia (CIN). PubMed and Web of Science were systematically searched for eligible publications from January 2000 to December 2017. Articles were selected on the basis of specific inclusion and exclusion criteria. The design and quality of all studies were evaluated using the Newcastle-Ottawa Scale (NOS). Odds ratios (ORs) with a 95% confidence interval (95% CI) were calculated. Thirteen eligible studies were selected to evaluate the association of vaginal microecology with HPV infection and CIN. The factors related to HPV infection were bacterial vaginosis (BV) (OR 2.57, 95% CI 1.78-3.71, P<0.05), Candida albicans (VVC) (OR 0.63, 95% CI 0.49-0.82, P < 0.05), Chlamydia trachomatis (CT) (OR 3.16, 95% CI 2.55-3.90, P < 0.05), and Ureaplasma urealyticum (UU) (OR 1.35, 95% CI 1.20-1.51, P < 0.05). BV was also related to CIN (OR 1.56, 95% CI 1.21-2.00, P < 0.05). This meta-analysis of available literature suggested an intimate association of vaginal microecology and HPV infection with CIN. BV, CT and UU were associated to increased HPV infection, VVC was associated to decreased HPV infection, Lactobacillus is not associated to increased HPV infection, BV was associated to increased CIN development risk. Further large-scale studies are needed to confirm our findings.

Diversity of vaginal microbiome and metabolome during genital infections

We characterized the vaginal ecosystem during common infections of the female genital tract, as vulvovaginal candidiasis (VVC, n = 18) and Chlamydia trachomatis infection (CT, n = 20), recruiting healthy (HC, n = 21) and bacterial vaginosis-affected (BV, n = 20) women as references of eubiosis and dysbiosis. The profiles of the vaginal microbiome and metabolome were studied in 79 reproductive-aged women, by means of next generation sequencing and proton based-nuclear magnetic resonance spectroscopy. Lactobacillus genus was profoundly depleted in all the genital infections herein considered, and species-level analysis revealed that healthy vaginal microbiome was dominated by L. crispatus. In the shift from HC to CT, VVC, and BV, L. crispatus was progressively replaced by L. iners. CT infection and VVC, as well as BV condition, were mainly characterised by anaerobe genera, e.g. Gardnerella, Prevotella, Megasphaera, Roseburia and Atopobium. The changes in the bacterial communities occurring during the genital infections resulted in significant alterations in the vaginal metabolites composition, being the decrease of lactate a common marker of all the pathological conditions. In conclusion, according to the taxonomic and metabolomics analysis, we found that each of the four conditions is characterized by a peculiar vaginal microbiome/metabolome fingerprint.

Cervical cancer stem cells and other leading factors associated with cervical cancer development

Cervical cancer (CC) is one of the leading causes of cancer-associated mortalities in women from developing countries. Similar to other types of cancer, CC is considered to be a multifactorial disease, involving socioeconomic, cultural, immunological and epigenetic factors, as well as persistent human papilloma virus (HPV) infection. It has been well established that cancer stem cells (CSCs) play an important role in defining tumor size, the speed of development and the level of regression following treatment; therefore, CSCs are associated with a poor prognosis. CSCs have been detected in many types of cancer, including leukemia, pancreatic, colon, esophagus, liver, prostate, breast, gastric and lung cancer. In cervical cancer, CSCs have been associated with resistance to normally used drugs such as cisplatin. The present review summarizes the strategies that high-risk HPV viruses (HPV-16 and HPV-18) have developed to transform normal epithelial cells into cancer cells, as well as the cellular pathways and studies associated with the identification of cervical cancer stem cell biomarkers. In this sense, the present review provides state of the art information regarding CC development.

Contrasting diversity of vaginal lactobacilli among the females of Northeast India

BACKGROUND

Lactobacilli are gatekeepers of vaginal ecosystem impeding growth of pathogenic microbes and their diversity varies across populations worldwide. The present study investigated diversity of human vaginal microbiota among females of Northeast India, who are distinct in dietary habits, lifestyle, and genomic composition from rest of India.

RESULTS

Altogether, 154 bacterial isolates were obtained from vaginal swab samples of 40 pregnant and 29 non-pregnant females. The samples were sequenced for 16 s rRNA gene and analysed for identification using a dual approach of homology search and maximum likelihood based clustering. Molecular identification based on 16S rRNA gene sequence confirmed the isolates belonging to 31 species. Lactobacilli constituted 37.7% of the bacterial isolates with 10 species and other Lactic Acid Bacteria (39.61%) represented another 10 species, some of which are opportunistic pathogens. The remaining of the communities are mostly dominated by species of Staphylococcus (14.28%) and rarely by Propionibacterium avidum (3.90%), Bacillus subtilis, Escherchia coli, Janthinobacterium lividum, and Kocuria kristinae (each 0.64%). Interestingly Lactobacillus mucosae and Enterococcus faecalis, which are globally uncommon vaginal microbes is found dominant among women of Northeast India. This tentatively reflects adaptability of particular Lactobacillus species, in distinct population, to better compete for receptors and nutrients in vaginal epithelium than other species. Further, intrageneric 16S rRNA gene exchange was observed among Enterococcus, Staphylococcus, and two species of Lactobacillus, and deep intraspecies divergence among L. mucosae, which pinpointed possibility of emergence of new strains with evolved functionality. Lactobacilli percentage decreased from young pregnant to aged non-pregnant women with maximum colonization in trimester II.

CONCLUSION

The study highlighted importance of assessment of vaginal microbiota, Lactobacillus in particular, across different population to gain more insight on female health.

Crosstalk between Vaginal Microbiome and Female Health: A review

Microbiota plays a fundamental role in the overall development and defences of human beings. The majority of indigenous microbiota exists in a mutually beneficial relationship with their hosts, while few of these are opportunistic pathogens that can lead to life-threatening diseases and chronic infections. These microbial communities constitute the primary defence against infections induced by non-indigenous invasive organisms. Female vaginal ecosystem thought to have been shaped over the years by co-evolutionary processes occurring between the particular microbial partners and the human host. Vaginal secretions contain numerous microorganisms and the host provides them nutrients for their growth and development. Disruptions in vaginal association with the microbiomes lead to the change in the vaginal environment, which enhanced the risk of acquiring diseases including sexually transmitted infections, bacterial vaginosis, fungal infections, preterm birth etc. The focus of this review is on the detailed analysis of vaginal microbiome interplay and its overall impact on female health. The mutualistic relationship between the vagina and residing microbial species has been well described. Finally, the recent advancements in the detection of microbiome interactions with the vaginal environment have been presented.

The vaginal microbiome in uterine transplantation

Women with congenital absolute uterine factor infertility (AUFI) often need vaginal restoration to optimise sexual function. Given their lack of procreative ability, little consideration has previously been given to the resultant vaginal microbiome (VM). Uterine transplantation (UTx) now offers the opportunity to restore these women's reproductive potential. The structure of the VM is associated with clinical and reproductive implications that are intricately intertwined with the process of UTx. Consideration of how vaginal restoration methods impact VM is now warranted and assessment of the VM in future UTx procedures is essential to understand the interrelation of the VM and clinical and reproductive outcomes. TWEETABLE ABSTRACT: The vaginal microbiome has numerous implications for clinical and reproductive outcomes in the context of uterine transplantation.

Polyomavirus JCPyV infrequently detectable in adenoid cystic carcinoma of the oral cavity and the airways

Our objective was to assess the presence of three polyomaviruses, namely SV40, JCPyV, and BKPyV, and human papillomaviruses (HPV) in adenoid cystic carcinomas (ACC) of the minor salivary glands (MiSG) in the head and neck region. The study comprised 68 MiSG ACC patients operated during 1974–2012 at the Helsinki University Hospital (Helsinki, Finland). Medical records and 68 histological samples were reviewed. Polyomaviruses were detected with quantitative PCR and the DNA-positive samples were further analyzed for the presence of viral tumor T antigen (T-ag) with immunohistochemistry. HPV genotyping was performed with a Multiplex HPV Genotyping Kit. Only JCPyV DNA was found in ACC samples, being present in 7 (10.3%) out of the 68 samples. The viral load of JCPyV was low varying between 1 to 226 copies/μg DNA. The JCPyV-positive samples originated from trachea (two samples), paranasal sinuses (one), and oral cavity (two). Additionally, JCPyV positivity was found in one lung metastasis of a tracheal tumor and one local disease failure of an oral cavity tumor. Three JCPyV DNA-positive samples showed weak nuclear staining for large T-ag. In conclusion, only JCPyV but not SV40, BKPyV, or HPV was found in ACC from the upper and lower airways. JCPyV copy numbers were low which might support its role as a “hit and run agent” in ACC carcinogenesis.

Vaginal dysbiosis and the risk of human papillomavirus and cervical cancer: systematic review and meta-analysis

OBJECTIVE

The vaginal microbiota proposedly influence the association between human papillomavirus and cervical cancer. Our aim was to assess whether vaginal dysbiosis affects human papilloma virus acquisition, persistence, and progression to related cervical premalignancy.

DATA SORUCES

MEDLINE, Embase, CINAHL, Cochrane Library, and Web of Science (inception until June 2018) were used for this study. The study protocol was registered at PROSPERO (CRD42016035620).

STUDY ELIGIBILITY CRITERIA

This systematic review included all observational studies reporting on incident human papilloma virus, persistent human papilloma virus, and/or related cervical disease in women with or without vaginal dysbiosis prior to outcome assessment.

STUDY APPRAISAL AND SYNTHESIS METHODS

We used random-effects models for meta-analyses and report pooled relative risks with 95% confidence intervals. The risk for incident and/or persistent human papilloma virus or related cervical disease based on longitudinal results was determined.

RESULTS

Of 1645 unique articles, 15 mainly prospective cohort studies were included, published between 2003 and 2017, including a total of 101,049 women. Vaginal dysbiosis was associated with an increased risk of incident human papilloma virus (overall relative risk, 1.33, 1.18-1.50, I² = 0%; among young women relative risk, 1.43, 1.10-1.85, I² = 0%), human papilloma virus persistence (overall relative risk, 1.14, 1.01-1.28, I² = 44.2%; for oncogenic types relative risk, 1.18, 1.01-1.38, I² = 0%), and high-grade lesions and cancer (relative risk, 2.01, 1.40-3.01, I² = 0%), but women with lesions/cancer were compared with those without, regardless of their oncogenic human papilloma virus status. Overall, comparable results were found in the molecular vaginal microbiota studies.

CONCLUSION

This study supports a causal link between vaginal dysbiosis and cervical cancer along the oncogenic human papillomavirus acquisition, persistence, and cervicovaginal dysplasia development pathway.

Composite Analysis of the Virome and Bacteriome of HIV/HPV Co-Infected Women Reveals Proxies for Immunodeficiency

The human cervical microbiome is complex, and its role in health and disease has just begun to be elucidated. In this study, 57 cervical swab samples from 19 HIV/HPV co-infected women were analyzed for both virome and bacteriome composition. Virome analysis focused on circular DNA viruses through rolling circle amplification followed by next-generation sequencing (NGS). Data were assigned to virus families and genera, and HPV types were identified. NGS data of bacterial 16S from a subset of 24 samples were assigned to operational taxonomic units and classified according to vaginal microbiome community state types (CSTs). Four viral families were found: Papillomaviridae, Anelloviridae, Genomoviridae, and Herpesviridae. Papillomavirus reads were more abundant in women with premalignant cervical lesions, which were also strongly associated with multiple (≥3) high-risk HPV infection. Anellovirus read abundance was negatively correlated with host CD4+ T-cell counts. The bacteriome revealed the presence of CST III and CST IV, and women with ≥1% frequency of genomovirus or herpesvirus reads displayed an increased risk of carrying CST IV. By characterizing the composition of the cervical circular DNA viruses and the bacteriome of HIV/HPV co-infected women, we identified putative interactions between these two microorganism communities and their associations with patients’ clinical characteristics, notably immunodeficiency status.

A novel sequencing-based vaginal health assay combining self-sampling, HPV detection and genotyping, STI detection, and vaginal microbiome analysis

The composition of the vaginal microbiome, including both the presence of pathogens involved in sexually transmitted infections (STI) as well as commensal microbiota, has been shown to have important associations for a woman's reproductive and general health. Currently, healthcare providers cannot offer comprehensive vaginal microbiome screening, but are limited to the detection of individual pathogens, such as high-risk human papillomavirus (hrHPV), the predominant cause of cervical cancer. There is no single test on the market that combines HPV, STI, and microbiome screening. Here, we describe a novel inclusive vaginal health assay that combines self-sampling with sequencing-based HPV detection and genotyping, vaginal microbiome analysis, and STI-associated pathogen detection. The assay includes genotyping and detection of 14 hrHPV types, 5 low-risk HPV types (lrHPV), as well as the relative abundance of 31 bacterial taxa of clinical importance, including Lactobacillus, Sneathia, Gardnerella, and 3 pathogens involved in STI, with high sensitivity, specificity, and reproducibility. For each of these taxa, reference ranges were determined in a group of 50 self-reported healthy women. The HPV sequencing portion of the test was evaluated against the digene High-Risk HPV HC2 DNA test. For hrHPV genotyping, agreement was 95.3% with a kappa of 0.804 (601 samples); after removal of samples in which the digene hrHPV probe showed cross-reactivity with lrHPV types, the sensitivity and specificity of the hrHPV genotyping assay were 94.5% and 96.6%, respectively, with a kappa of 0.841. For lrHPV genotyping, agreement was 93.9% with a kappa of 0.788 (148 samples), while sensitivity and specificity were 100% and 92.9%, respectively. This novel assay could be used to complement conventional cervical cancer screening, because its self-sampling format can expand access among women who would otherwise not participate, and because of its additional information about the composition of the vaginal microbiome and the presence of pathogens.

The cervical microbiota in reproductive-age South African women with and without human papillomavirus infection

In this study we examined potential associations of HPV infection with the cervical microbiota. Cervical samples were collected from 87 HIV-seronegative reproductive-age Black South African women. Microbiota were characterized by Illumina sequencing of the V3-V4 hypervariable regions of the bacterial 16S rRNA gene. Thirty seven (42.5%) and 30 (34.5%) of the women had prevalent HPV and high-risk (HR)-HPV, respectively. Only 23 women (26.4%) had cervical microbiota dominated by a single Lactobacillus species (L. crispatus (2/87 (2.3%)), L. jensenii (2/87 (2.3%)), and L. iners (19/87 (21.8%)). The majority of the women (56/87 (64.4%)) had diverse cervical microbiota consisting of mainly bacterial vaginosis-associated bacteria. The remaining women (8/87 (9.2%)) had microbiota dominated by Aerococcus, Streptococcus, Chlamydia or Corynebacterium. Women with HR-HPV had significantly higher relative abundances of Aerococcaceae, Pseudomonadaceae and Bifidobacteriaceae compared to those with low-risk (LR)-HPV or no HPV-infection (LDA score >2.0, p < 0.05, q < 0.2). Gardnerella, Sneathia, and Atopobium were also found at greater relative abundances in HR-HPV-infected women compared to those with low-risk (LR)-HPV or no HPV-infection (LDA score >2.0, p < 0.05), although the difference was not significant after FDR-adjustment (q > 0.2). Further investigations of the bacterial taxa significantly enriched in HR-HPV-infected women are warranted.

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Majority of participants (74%) had cervical microbiota not dominated by Lactobacillus.

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Lactobacillus was not enriched in HPV-negative women compared to HPV-positive women.

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There was no correlation between cervical microbiota diversity and HPV infection.

Relationship between the Cervical Microbiome, HIV Status, and Precancerous Lesions

Nearly all cervical cancers are causally associated with human papillomavirus (HPV). The burden of HPV-associated dysplasias in sub-Saharan Africa is influenced by HIV. To investigate the role of the bacterial microbiome in cervical dysplasia, cytobrush samples were collected directly from cervical lesions of 144 Tanzanian women. The V4 hypervariable region of the 16S rRNA gene was amplified and deep sequenced. Alpha diversity metrics (Chao1, PD whole tree, and operational taxonomic unit [OTU] estimates) displayed significantly higher bacterial richness in HIV-positive patients (P = 0.01) than in HIV-negative patients. In HIV-positive patients, there was higher bacterial richness in patients with high-grade squamous intraepithelial lesions (HSIL) (P = 0.13) than those without lesions. The most abundant OTUs associated with high-grade squamous intraepithelial lesions were Mycoplasmatales, Pseudomonadales, and Staphylococcus We suggest that a chronic mycoplasma infection of the cervix may contribute to HPV-dependent dysplasia by sustained inflammatory signals.IMPORTANCE HPV is known to be the causal agent in the majority of cervical cancers. However, the role of the cervical bacterial microbiome in cervical cancer is not clear. To investigate that possibility, we collected cervical cytobrush samples from 144 Tanzanian women and performed deep sequencing of bacterial 16S rRNA genes. We found that HIV-positive patients had greater bacterial richness (P = 0.01) than HIV-negative patients. We also observed that women with high-grade squamous intraepithelial lesions (HSIL) had greater cervical bacterial diversity than women with cytologically normal cervices. Data from our precise sampling of cervical lesions leads us to propose that Mycoplasma contributes to a cervical microbiome status that promotes HPV-related cervical lesions. These results suggest a greater influence of the bacterial microbiota on the outcome of HPV infection than previously thought.

Cervical microbiota in women with cervical intra-epithelial neoplasia, prior to and after local excisional treatment, a Norwegian cohort study

Background

Local treatment for cervical intraepithelial neoplasia (CIN) by Loop Electrosurgical Excision Procedure (LEEP) has been correlated with reproductive morbidity, while the cervicovaginal microbiota is also known to affect the risk of preterm delivery. CIN and treatment by LEEP might change the cervical microbiota. The main aim of this study was to describe the cervical microbiota before and after LEEP and assess its associaton with cone depth and HPV persistence. Further, we aimed to compare the microbiota to references with normal cervical cytology.

Methods

Between 2005 and 2007, we prospectively identified 89 women planned for LEEP in a Norwegian hospital and recruited 100 references with a normal cervical cytology. Endocervical swabs were collected prior to treatment and at six (n = 77) and 12 months (n = 72) post LEEP for bacterial culture and PCR, and post LEEP for DNA testing for human papillomavirus (HPV). We compared the cervical microbiota composition before and after treatment and between women planned for LEEP vs references.

Results

There was a reduction in the number of non-Lactobacillus bacterial species six and 12 months after LEEP compared to before treatment and a tendency towards a concomitant increase in Lactobacillus. No association between the detection of cervical bacteria, HPV persistence or cone depth was found.

Women planned for LEEP carried significantly more Bacteroides spp., Gardnerella vaginalis, Mycoplasma hominis and Ureaplasma parvum as well as a greater number of bacterial species than the references.

Conclusions

Local excisional treatment appears to alter the cervical microbiota towards a less diverse microbiota. Women with CIN have a more diverse cervical microbiota compared to women with normal cervical cytology.

Electronic supplementary material

The online version of this article (10.1186/s12905-019-0727-0) contains supplementary material, which is available to authorized users.

Interplay among Vaginal Microbiome, Immune Response and Sexually Transmitted Viral Infections

The vaginal ecosystem is important for women's health and for a successful reproductive life, and an optimal host-microbial interaction is required for the maintenance of eubiosis. The vaginal microbiota is dominated by Lactobacillus species in the majority of women. Loss of Lactobacillus dominance promotes the colonization by anaerobic bacterial species with an increase in microbial diversity. Vaginal dysbiosis is a very frequent condition which affects the immune homeostasis, inducing a rupture in the epithelial barrier and favoring infection by sexually transmitted pathogens. In this review, we describe the known interactions among immune cells and microbial commensals which govern health or disease status. Particular attention is given to microbiota compositions which, through interplay with immune cells, facilitate the establishment of viral infections, such as Human Immunodeficiency Virus (HIV), Human Papilloma Virus (HPV), Herpes Simplex Virus 2 (HSV2).

Association of human papillomavirus and bacterial vaginosis with increased risk of high-grade squamous intraepithelial cervical lesions

OBJECTIVE

To assess the rates of co-infections between human papillomavirus (HPV) and 13 key markers of bacterial vaginosis in cervical samples by multiplex polymerase chain reaction in a population with a high rate of abnormal cytology and a positive HPV test.

METHODS

The study included a total of 213 women aged 18-72 years screened using Papanicolaou smears for determining cervical abnormalities and for HPV and bacterial vaginosis by single-target and multiplex polymerase chain reaction.

RESULTS

A total of 83 (39%) women were negative for intraepithelial lesion or malignancy cytology and 130 (61%) had abnormal cytology. HPV-DNA prevalence was 69.9% and bacterial vaginosis was 72.7 %. Co-infections between bacterial vaginosis with HPV-DNA and high-risk HPV were associated with an increased risk for squamous intraepithelial lesions of low-grade cytology and high-grade squamous intraepithelial lesions plus cervical cancer. The most frequent bacterial vaginosis agent was Gardnerella vaginalis (33.8%), and co-infection with HPV-DNA and high-risk HPV increased the risk for squamous intraepithelial lesions of low grade cytology and high-grade squamous intraepithelial lesions plus cervical cancer. Co-infection between Megasphaera type I and high-risk HPV increased the risk for high-grade squamous intraepithelial lesions plus cervical cancer.

CONCLUSIONS

Our results reinforce the hypothesis that some bacterial vaginosis agents may play a role as co-factors in HPV-mediated cervical carcinogenesis, at least in some populations.

Association of cervical microbial community with persistence, clearance and negativity of Human Papillomavirus in Korean women: a longitudinal study

The present study aimed to identify the cervical microbes that are associated with HPV negativity, HPV clearance and HPV persistence and to assess the microbes’ longitudinal associations as related to HPV infection dynamics among Korean women. We enrolled 41 women with 107 samples, and classified them according to the HPV infection dynamics: HPV negativity (21 samples, 10 subjects), HPV clearance (42 samples, 15 subjects), and HPV persistence (44 samples, 16 subjects). Cervical swabs were collected at the baseline and six-month-interval follow-up visits. HPV positivity was determined by HPV DNA HC2 assay, and the microbiome was analyzed using 16SrRNA pyrosequencing, linear discriminant analysis effect size and multivariate logistic analysis. In the multivariate logistic analysis results, Lactobacillus crispatus (multivariate OR (mOR) = 8.25, 95% CI 2.13~32.0) was predominant in the HPV-negative group. We observed that Eubacterium eligens (mOR = 11.5, 95% CI 1.31~101.4), Gardnerella vaginalis (mOR = 17.0, 95% CI 2.18–131.8), and Ureaplasma urealyticum (mOR = 7.42, 95% CI 1.3–42.46) had the strongest associations with HPV clearance, and Lactobacillus johnsonii (mOR = 16.4, 95% CI 1.77–152.2) with HPV persistence. Overall, greater diversity was observed in HPV-persistence than in HPV-negative women. Our findings suggest that the presence and prevalence of a specific cervical microbiome are factors involved in HPV dynamics.

Microbiota dysbiosis is associated with HPV-induced cervical carcinogenesis

Cervical microbial communities serve a crucial role in the persistence and development of oncogenic human papilloma virus (HPV) infections. In the present study, the authors hypothesised that disturbed heterogeneity of microbial flora was associated with HPV-induced carcinogenesis. Swabs of the cervical microbiota were collected from 250 women and the 16S ribosomal DNA was sequenced using a high throughput assay. The swabs of cervical microbiota were grouped according to the community state types (CSTs) as follows: Healthy cervical swabs; swabs taken from low-grade squamous intra-epithelial lesions (LSIL) and swabs taken from high-grade squamous intra-epithelial lesions (HSIL). Analysis of the bacterial classes revealed that the CST cervical swabs of the volunteers were characterised by Lactobacillus crispatus, Lactobacillus iners and Lactobacillus taiwanensis, however, Gardnerella vaginalis and Lactobacillus acidophilus were absent. In the CST of patients with LSIL the predominant type of bacteria was Lactobacillus acidophilus and Lactobacillus iners, however Lactobacillus crispatus was not detected. Swabs from CST women diagnosed with HSIL exhibited abundant Gardnerella vaginalis and Lactobacillus acidophilus, however, lacked Lactobacillus taiwanensis, Lactobacillus iners and Lactobacillus crispatus. The abundance of Lactobacillus acidophilus in swabs from the healthy women was compared with the swabs from the women with LSIL. The results of the present study indicated that the development of HPV-induced cancer is associated with a high diversity of vaginal microbiota, which is involved in the control of viral persistence, and is therefore indicative of disease prognosis.

Lactobacillus crispatus accelerates re-epithelialization in vaginal epithelial cell line MS74

PROBLEM

The functions of vaginal lactobacilli in susceptibility to infectious diseases as regards epithelial barrier integrity and wound healing remain incompletely understood.

METHOD OF STUDY

Lactobacillus crispatus, one of the most common Lactobacillus species in the vagina and among the most protective against sexually transmitted infections, was cocultured with an immortalized human vaginal epithelial cell line (MS74), and a scratch assay was performed to evaluate re-epithelialization. The concentration of vascular endothelial growth factor A (VEGF) was measured using enzyme-linked immunosorbent assay (ELISA). An immunofluorescence assay was performed to locate the expression of VEGF and VEGF receptor (VEGFR) 1 and 2. The effects of the bacterial supernatant of L. crispatus were also evaluated.

RESULTS

Lactobacillus crispatus significantly accelerated re-epithelialization of MS74 cells, accompanied by an increase in VEGF concentration. In contrast, heat-killed L. crispatus did not show this effect. The bacterial supernatant of L. crispatus also induced re-epithelialization. The immunoreactivity of VEGF was higher at the scratched edge, whereas VEGFR1 and 2 stained site-independently. Recombinant VEGF induced cell migration in a dose-dependent manner. The bacterial supernatant of L. crispatus also significantly accelerated re-epithelialization in MS74 cells and increased the concentration of VEGF in the culture 24 hours after the scratch.

CONCLUSION

These results may enhance our knowledge of the importance of L. crispatus in the healing of damaged vaginal epithelium and protection against the consequent risk of pathogenic infections, such as human immunodeficiency virus (HIV), and improve our understanding of vaginal epithelial barrier integrity maintenance by this bacterium.

The Performance of an Oral Microbiome Biomarker Panel in Predicting Oral Cavity and Oropharyngeal Cancers

The oral microbiome can play a role in the instigation and progression of oral diseases that can manifest into other systemic conditions. These associations encourage the exploration of oral dysbiosis leading to the pathogenesis of cancers. In this study, oral rinse was used to characterize the oral microbiome fluctuation associated with oral cavity cancer (OCC) and oropharyngeal cancers (OPC). The study cohort consists of normal healthy controls (n = 10, between 20 and 30 years of age; n = 10, above 50 years of age), high-risk individuals (n = 11, above 50 years of age with bad oral hygiene and/or oral diseases) and OCC and OPC patients (n = 31, HPV-positive; n = 21, HPV-negative). Oral rinse samples were analyzed using 16S rRNA gene amplicon sequencing on the MiSeq platform. Kruskal–Wallis rank test was used to identify genera associated with OCC and OPC. A logistic regression analysis was carried out to determine the performance of these genera as a biomarker panel to predict OCC and OPC. In addition, a two-fold cross-validation with a bootstrap procedure was carried out in R to investigate how well the panel would perform in an emulated clinical scenario. Our data indicate that the oral microbiome is able to predict the presence of OCC and OPC with sensitivity and specificity of 100 and 90%, respectively. With further validation, the panel could potentially be implemented into clinical diagnostic and prognostic workflows for OCC and OPC.

The spleen microbiota of small wild mammals reveals distinct patterns with tick-borne bacteria

Background

Wild mammals serve as reservoirs for a variety of microbes and play an important role in the enzootic cycles of these microbes. Some of them are vector-borne bacteria in the genera Anaplasma, Ehrlichia and Rickettsia of the order Rickettsiales, which can cause febrile illnesses in human beings as well as animals. Anaplasma spp., Ehrlichia spp. and many spotted fever group (SFG) Rickettsia spp. are transmitted to mammalian hosts by tick vectors during blood meals. As a powerful sequencing method, the next generation sequencing can reveal the complexity of bacterial communities in humans and animals. Compared with limited studies on blood microbiota, however, much fewer studies have been carried out on spleen microbiota, which is very scarce in wild mammals. Chongming Island is the third biggest island in China. It was unclear whether there were any vector-borne bacteria in Chongming Island. In the present study, we explored the bacterial microbiota in the spleens of wild mice and shrews from the rural areas of Chongming Island and investigated the prevalence of vector-borne bacteria.

Methodology/Principal findings

Genomic DNAs were extracted from the spleen samples of 35 mice and shrews. The 16S rDNA V3-V4 regions of the DNA extracts were amplified by PCR and subjected to the 16S rDNA-targeted metagenomic sequencing on an Illumina MiSeq platform. All the 35 spleen samples obtained data with sufficient coverage (99.7–99.9%) for analysis. More than 1,300,000 sequences were obtained after quality control and classified into a total of 1,967 operational taxonomic units (OTUs) clustered at 97% similarity. The two most abundant bacterial phyla were Firmicutes and Proteobacteria according to the analysis of rarefied sequences. Among the bacterial communities detected in this study, Anaplasma, Rickettsia and Coxiella were adjacently clustered by hierarchical analysis. Significant differences in many bacterial features between Anaplasma-positive and Anaplasma-negative samples were identified by LEfSe analysis and Wilcoxon rank-sum test, suggesting that the Anaplasma-infection of small wild mammals was associated with a specific pattern of spleen microbiota.

Conclusions/Significance

Our study has comprehensively characterized the complex bacterial profiles in the spleens of wild mice and shrews from Chongming Island, Shanghai city. This work has revealed distinct spleen bacterial communities associated with tick-borne bacteria in wild animals. The detection of tick-borne bacteria highlights the risk of contracting pathogens with public health importance upon tick-exposure in the studied areas.

In this study, the 16S rDNA-targeted metagenomic sequencing was used to determine the bacterial community and diversity in the spleens of small wild mammals from China. The 16S rDNAs were amplified from the spleen genomic DNAs of 35 small wild mice and shrews and sequenced by Illumina MiSeq technology. More than 1,300,000 sequences were obtained after quality control and classified into a total of 1,967 operational taxonomic units (OTUs) clustered at 97% similarity. The two most abundant bacterial phyla were Firmicutes and Proteobacteria according to the analysis of rarefied sequences. Within the bacterial communities detected in this study, vector-borne bacteria, Anaplasma, Rickettsia and Coxiella, were adjacently clustered by hierarchical analysis. Significant differences in many bacterial features between Anaplasma-positive and Anaplasma-negative samples were observed, suggesting that the infection of small wild mammals with Anaplasma is associated with a distinct pattern of spleen microbiota. This study has revealed the complex bacterial profiles in the spleens of wild mice and shrews. The detection of vector-borne bacteria highlights the role of wild mice and shrews as animal reservoirs with potential public health importance in the studied areas.

HPV infection and bacterial microbiota in the placenta, uterine cervix and oral mucosa

We investigated the association between HPV infection and bacterial microbiota composition in the placenta, uterine cervix and mouth in thirty-nine women. HPV DNA genotyping of 24 types was conducted using Multimetrix®. Microbiota composition was characterized by 16S rRNA gene sequencing. HPV DNA was detected in 33% of placenta, 23% cervical and 33% oral samples. HPV16 was the most frequent type in all regions. HPV infection was associated with higher microbiota richness (p = 0.032) in the mouth but did not influence microbial diversity or richness in other samples. HPV infection was associated with higher abundance of Lactobacillaceae (p = 0.0036) and Ureaplasma (LDA score > 4.0, p < 0.05) in the placenta, Haemophilus (p = 0.00058) and Peptostreptococcus (p = 0.0069) genus in the cervix and Selenomonas spp. (p = 0.0032) in the mouth compared to HPV negative samples. These data suggest altered bacterial microbiota composition in HPV positive placenta, cervix and mouth. Whether the changes in bacterial microbiota predispose or result from HPV remains to be determined in future studies.

Self-Sampling for Human Papillomavirus Testing: Increased Cervical Cancer Screening Participation and Incorporation in International Screening Programs

In most industrialized countries, screening programs for cervical cancer have shifted from cytology (Pap smear or ThinPrep) alone on clinician-obtained samples to the addition of screening for human papillomavirus (HPV), its main causative agent. For HPV testing, self-sampling instead of clinician-sampling has proven to be equally accurate, in particular for assays that use nucleic acid amplification techniques. In addition, HPV testing of self-collected samples in combination with a follow-up Pap smear in case of a positive result is more effective in detecting precancerous lesions than a Pap smear alone. Self-sampling for HPV testing has already been adopted by some countries, while others have started trials to evaluate its incorporation into national cervical cancer screening programs. Self-sampling may result in more individuals willing to participate in cervical cancer screening, because it removes many of the barriers that prevent women, especially those in low socioeconomic and minority populations, from participating in regular screening programs. Several studies have shown that the majority of women who have been underscreened but who tested HPV-positive in a self-obtained sample will visit a clinic for follow-up diagnosis and management. In addition, a self-collected sample can also be used for vaginal microbiome analysis, which can provide additional information about HPV infection persistence as well as vaginal health in general.

Cervical microbiome is altered in cervical intraepithelial neoplasia after loop electrosurgical excision procedure in china

Although human papillomavirus (HPV) infection is a major cause leading to the development of cervical intraepithelial neoplasia (CIN), the relationship between genital microbiome and HPV persistence/clearance is not well established. Loop electrosurgical excision procedure (LEEP) is one of standard treatments of CIN 2/3 globally, yet little is known about how the LEEP influence genital microbiota. We conducted a prospective study of 26 patients with CIN2/3 who underwent analysis of cervical microbiome before and after 3 months of LEEP treatment. Cervical swabs were collected, and microbiomes were analyzed by 16S ribosomal RNA gene sequencing. A decrease of cervical microbial diversity was observed after 3 months of LEEP treatment. Notably, a significant shift from community type of a Prevotella-containing and lack of a consistent dominant species to lactobacillus iners dominated microbiome correlated with LEEP. Particularly, Leptotrichia and clostridium were further decreased after LEEP treatment (P = 0.049 and P = 0.002, respectively). Our results suggest that the cervical microbiome is altered after LEEP treatment in patients with CIN2/3. Further studies with larger sample sizes are needed to validate these findings.

Uterine Microbiota: Residents, Tourists, or Invaders?

Uterine microbiota have been reported under various conditions and populations; however, it is uncertain the level to which these bacteria are residents that maintain homeostasis, tourists that are readily eliminated or invaders that contribute to human disease. This review provides a historical timeline and summarizes the current status of this topic with the aim of promoting research priorities and discussion on this controversial topic. Discrepancies exist in current reports of uterine microbiota and are critically reviewed and examined. Established and putative routes of bacterial seeding of the human uterus and interactions with distal mucosal sites are discussed. Based upon the current literature, we highlight the need for additional robust clinical and translational studies in this area. In addition, we discuss the necessity for investigating host–microbiota interactions and the physiologic and functional impact of these microbiota on the local endometrial microenvironment as these mechanisms may influence poor reproductive, obstetric, and gynecologic health outcomes and sequelae.

Multiple types of human papillomavirus infection and anal precancerous lesions in HIV-infected men in Taiwan: a cross-sectional study

OBJECTIVES

This study aimed to assess the relationship between infection with multiple human papillomavirus (HPV) types and abnormal anal cytology in HIV-infected men.

DESIGN

An observational, cross-sectional study.

SETTING

A regional referral hospital in Taiwan.

PARTICIPANTS

In total, 714 HIV-infected men were enrolled between March 2011 and June 2016. Thin preparation anal Pap smears were interpreted according to the 2001 Bethesda System. Thirty-seven types of HPV were detected by reverse line blotting, including 13 oncogenic types and 24 non-oncogenic types.

OUTCOME MEASURES

The relationship between anal HPV infection and abnormal anal cytology in people of Asian ethnicity and the coverage efficacy in HPV-vaccinated HIV-infected men.

RESULTS

On anal cytology, 175 (24.5%) subjects had atypical squamous cells of undetermined significance (ASCUS) or higher grades of dysplasia, including 87 (49.7%) with ASCUS, 73 (41.7%) with low-grade squamous intraepithelial lesions (LSILs) and 15 (8.6%) with high-grade squamous intraepithelial lesions (HSILs). A higher proportion of subjects with those without LSIL/HSIL (93.1% vs 67.3%, P<0.0001) had multiple HPV types. The odds of having LSIL/HSIL increased with an increasing number of HPV types: the ORs ranged from 1 for no HPV types to 6.96 (95% CI 2.38 to 20.37) for more than five types (P_trend <0.0001). Multivariate logistic regression analysis showed a significant association between LSIL/HSIL and the number of HPV genotypes present (OR 1.20; 95% CI 1.02 to 1.42, P<0.05). HPV types covered by the nonavalent HPV vaccine (types 6/11/16/18/31/33/45/52/58) were detected in 70.1% of the patients in this study.

CONCLUSIONS

The odds of having anal LSIL/HSIL are approximately seventimes greater in HIV-infected men with than withoutsix or more types of HPV. Multiple HPV types in HIV-infected patients deserves aggressive follow-up, and HPV vaccination programme require scaling up.

Long-term Lactobacillus rhamnosus BMX 54 application to restore a balanced vaginal ecosystem: a promising solution against HPV-infection

Background

Over recent years, a growing interest has developed in microbiota and in the concept of maintaining a special balance between Lactobacillus and other bacteria species in order to promote women’s well-being. The aim of our study was to confirm that vaginal Lactobacilli long-lasting implementation in women with HPV-infections and concomitant bacterial vaginosis or vaginitis might be able to help in solving the viral infection, by re-establishing the original eubiosis.

Methods

A total of 117 women affected by bacterial vaginosis or vaginitis with concomitant HPV-infections were enrolled at Department of Gynecological Obstetrics and Urological Sciences, La Sapienza University, Rome, Italy between February 2015 and March 2016. Women were randomized in two groups, standard treatment (metronidazole 500 mg twice a day for 7 days or fluconazole 150 mg orally once a day for 2 consecutive days) plus short-term (3 months) vaginal Lactobacillus implementation (group 1, short probiotics treatment protocol group, n = 60) versus the same standard treatment plus long-lasting (6 months) vaginal Lactobacillus rhamnosus BMX 54 administration (group 2, treatment group, n = 57).

Results

After a median follow up of 14 months (range 9–30 months) the chance to solve HPV-related cytological anomalies was twice higher in probiotic long-term users (group 2) versus short probiotics implementation group (group 1) (79.4% vs 37.5%, p = 0.041). Moreover, a total HPV-clearance was shown in 11.6% of short schedule probiotics implementation patients compared to a percentage of 31.2% in vaginal Lactobacilli long term users (p = 0.044), assessed as negative HPV-DNA test documented at the end of the study period.

Conclusions

The consistent percentage of clearance of PAP-smear abnormalities and HPV-clearance obtained in long-term treatment group has been interestingly high and encouraging. Obviously, larger and randomized studies are warranted to confirm these encouraging results, but we believe that eubiosis re-establishment is the key to tackle effectively even HPV-infection.

Trial registration

Retrospectively registered on PRS NCT03372395 (12/12/2017).