Microbiota dysbiosis is associated with HPV-induced cervical carcinogenesis

Vaginal microbiota and gynecological cancers: a complex and evolving relationship

The vagina hosts a community of microorganisms known as the vaginal microbiota. This community is relatively stable and straightforward, with Lactobacillus species being the most dominant members. The vaginal microbiota has various functions that are essential for maintaining human health and balance. For example, it can metabolise dietary nutrients, produce growth factors, communicate with other bacteria, modulate the immune system, and prevent the invasion of harmful pathogens. When the vaginal microbiota is disrupted, it can lead to diseases and infections. The observed disturbance is distinguished by a reduction in the prevalence of Lactobacillus and a concurrent rise in the number of other bacterial species that exhibit a higher tolerance to low oxygen levels. Gynecologic cancers are a group of cancers that affect the female reproductive organs and tissues, such as the ovaries, uterus, cervix, vagina, vulva, and endometrium. These cancers are a major global health problem for women. Understanding the complex interactions between the host and the vaginal microorganisms may provide new insights into the prevention and treatment of gynecologic cancers. This could improve the quality of life and health outcomes for women.

Microbiota changes: the unseen players in cervical cancer progression

Cervical cancer ranks among the most prevalent cancers globally with high-risk human papillomaviruses implicated in nearly 99% of cases. However, hidden players such as changes in the microbiota are now being examined as potential markers in the progression of this disease. Researchers suggest that changes in the vaginal microbiota might correlate with cervical cancer. This review provides a comprehensive look at the microbiota changes linked with the advancement of cervical cancer. It also scrutinizes the databases from past studies on the microbiota during healthy and cancerous stages, drawing connections between prior findings concerning the role of the microbiota in the progression of cervical cancer. Preliminary findings identify Fusobacterium spp., Peptostreptococcus spp., Campylobacter spp., and Haemophilus spp., as potential biomarkers for cervical cancer progression. Alloscardovia spp., Eubacterium spp., and Mycoplasma spp. were identified as potential biomarkers for HPVs (+), while Methylobacterium spp. may be indicative of HPV (-). However, the study's limitations, including potential biases and methodological constraints, underscore the need for further research to validate these findings and delve deeper into the microbiota's role in HPV development. Despite these limitations, the review provides valuable insights into microbiota trends during cervical cancer progression, offering direction for future research. The review summarizes key findings from previous studies on microbiota during healthy and cancerous stages, as well as other conditions such as CIN, SIL, HPV (+), and HPV (-), indicating a promising area for further investigation. The consistent presence of HPV across all reported cervical abnormalities, along with the identification of distinct bacterial genera between cancerous and control samples, suggests a potential link that merits further exploration. In conclusion, a more profound understanding of the microbial landscape could elucidate the pathogenesis of cervical diseases and inform future strategies for diagnosis, prevention, and treatment.

A Landscape View of the Female Genital Tract Microbiome in Healthy Controls and Women With Reproductive Health Conditions Associated With Ectopic Pregnancy

Disruption of the female genital microbiome is associated with several pregnancy complications, including miscarriage, preterm onset of labour, and tubal pregnancy. Ectopic pregnancy is a known cause of maternal morbidity and mortality, but early diagnosis and treatment of ectopic pregnancy remain a challenge. Despite growing established associations between genital microbiome and female reproductive health, few studies have specifically focused on its link with ectopic pregnancy. Therefore, the current review aims to provide a comprehensive account of the female genital microbiome in healthy and fertile women compared to those in ectopic pregnancy and its associated risk factors. The microbial diversity from various sites of the female genital tract was explored for a reliable proxy of female reproductive health in sequencing-based ectopic pregnancy research. Our report confirmed the predominance of Lactobacillus in the vagina and the cervix among healthy women. The relative abundance decreased in the vaginal and cervical microbiome in the disease state. In contrast, there were inconsistent findings on the uterine microbiome across studies. Additionally, we explore a spectrum of opportunities to enhance our understanding of the female genital tract microbiome and reproductive conditions. In conclusion, this study identifies gaps within the field and emphasises the need for visionary solutions in metagenomic tools for the early detection of ectopic pregnancy and other gynaecological diseases.

A Decrease in Lactobacilli in the Vaginal Microbiota Is Independently Associated With HPV Persistence in Women With High-Risk HPV Infection

Background Vaginal dysbiosis, an imbalance between species, can initiate some local changes in immune and metabolic signaling causing chronic inflammation. The mechanism of the clearance or progression of the HPV infection has not been uncovered yet. We hypothesized that vaginal dysbiosis may contribute to the persistence of the cervical HPV infection. Therefore we aimed to determine the association of lactobacillus dominancy index with cervical HR-HPV persistence. Methods A total of 100 women who were followed up because of high-risk HPV infection were defined as the target study group. The patients were evaluated in two groups; HPV positive (group with HPV persistence, n=43) and HPV negative (group with HPV clearance, n=57). Cervicovaginal swab samples and blood samples were evaluated for Nugent score, lactobacillus dominance, and white blood cell count. Statistical tests were performed by the IBM Statistical Product and Service Solutions (version 22, IBM SPSS Statistics for Windows, Armonk, NY) program. The continuous variables were presented using the mean±standard deviation (SD), and the categorical variables were presented as the number of cases and their percentage. A p value less than 0.05 (<0.05) was set as statistically significant. Results HPV persistence was observed in 43 (43%) patients. Univariate analysis revealed that age, menopausal status, and lactobacillus reduction were associated with HPV persistence (p<0.05). The median value of the Nugent score was similar among groups. After logistic regression analysis, lactobacillus reduction continued to be associated with HPV persistence, independent of age and menopause (OR: 2.668, 96% CI: 1.069-6.662, p<0.05) Conclusions A decrease in lactobacilli in the cervicovaginal microbiota is associated with the persistence of HPV, regardless of age and menopausal status in this study.

Characteristics of vaginal microbiota in various cervical intraepithelial neoplasia: a cross-sectional study

BACKGROUND

Precancerous lesions of cervical cancer exhibit characteristics indicative of natural progression. To prevent overtreatment of patients whose cervical intraepithelial neoplasia (CIN) in regression and to predict the onset of invasive cervical cancer at an early stage, we've identified the vaginal microbiome as a potential key factor, which is associated with both HPV infection and the various cervical intraepithelial neoplasia. This study aims to investigate the microbiome characteristics of patients with various cervical intraepithelial neoplasia.

METHODS

Utilizing high-throughput 16S ribosomal RNA (16S rRNA) sequencing technology, a description of the characteristics and community composition of Vaginal Microbiota (VMB) was conducted among 692 Chinese women infected with the High-risk Human Papillomavirus (HR-HPV).

RESULTS

As the grade of the lesions increased, the proportions of Lactobacillus and Pseudomonas demonstrated a significant declining trend, while the proportions of Gardnerella, Dialister, and Prevotella significantly increased. The diversity of the VMB was more significant in high-grade CIN. Furthermore, KEGG pathway enrichment analysis indicates that high-grade cervical intraepithelial neoplasia can inhibit various pathways, including those of phosphotransferase system, transcription factors, Fructose and mannose metabolism, amino sugar and nucleotide sugar metabolism, and galactose metabolism, which may contribute to the development of early cervical cancer symptoms.

CONCLUSION

Patients with CIN exhibit a distinct vaginal microbial profile characterized by a decrease in Lactobacillus and Pseudomonas, and an increase in Gardnerella, Prevotella, and Dialister. The proliferation and diminution of these two types of microbial communities are interrelated, suggesting a mutual restraint and balance among them. Disruption of this regulatory balance could potentially lead to the onset of cervical lesions and carcinogenesis. Retrospectively registered: This study was approved by the Ethics Committee of the Beijing Chaoyang Hospital affiliated with the Capital Medical University (NO.2023-S-415).

The analysis of Lactobacillus spp. distribution in the vaginal microbiota of Polish women with abnormal Pap smear result

Introduction

A healthy vaginal microbiota is represented mainly by Lactobacillus spp. and plays a vital role in maintaining the functional balance in the vaginal environment. Scientists have drawn attention to possible correlations between the vaginal microbiome and gynecological neoplasms. Several recent studies have shown a potential link between the vaginal microbiome and the risk of developing cervical cancer from human papillomavirus (HPV) infection. This study aimed to compare the prevalence and abundance of various lactic acid bacteria species (LABs) in vaginal swabs from healthy controls and patients with abnormal Pap smear results.

Methods

The study included 100 women (79 patients with abnormal cervical Pap smear results and 21 controls) from whom vaginal swabs were collected. Real-time quantitative PCR was used to determine seven lactic acid bacteria (LAB) species and their quantities.

Results

Most patients were colonized by two Lactobacillus species, primarily Lactobacillus gasseri (93%) and L. crispatus (83%). Patient age and place of residence were associated with the diversity of LAB in the vaginal microbiota. The abundance of L. delbrueckii in the vaginal microbiota increased, whereas the abundance of L. gasseri abundance decreased, with patient age. Lactobacillus acidophilus and Limosilactobacillus fermentum were significantly more often detected in patients living in rural versus urban areas. Statistical analysis did not show any significant differences in LAB between groups of patients with various changes on smear tests.

Discussion

The degree of dysplastic changes in the endothelium or the presence of a group of atypical cervical stratified epithelial cells was not associated with significant changes in the studied vaginal bacteria.

Longitudinal analysis on the ecological dynamics of the cervicovaginal microbiome in hrHPV infection

The cervicovaginal microbiome (CVM) is a dynamic continuous microenvironment that can be clustered in microbial community state types (CSTs) and is associated with women's cervical health. Lactobacillus-depleted communities particularly associate with an increased susceptibility for persistence of high-risk human papillomavirus (hrHPV) infections and progression of disease, but the long-term ecological dynamics of CSTs after hrHPV infection diagnosis remain poorly understood. To determine such dynamics, we examined the CVM of our longitudinal cohort of 141 women diagnosed with hrHPV infection at baseline with collected cervical smears at two timepoints six-months apart. Here we describe that the long-term microbiome dissimilarity has a positive correlation with microbial diversity at both visits and that women with high abundance and dominance for Lactobacillus iners at baseline exhibit more similar microbiome composition at second visit than women with Lactobacillus-depleted communities at baseline. We further show that the species Lactobacillus acidophilus and Megasphaera genomosp type 1 associate with CST changes between both visits. Lastly, we also observe that Gardnerella vaginalis is associated with the stability of Lactobacillus-depleted communities while L. iners is associated with the instability of Megasphaera genomosp type 1-dominated communities. Our data suggest dynamic patterns of cervicovaginal CSTs during hrHPV infection, which could be potentially used to develop microbiome-based therapies against infection progression towards disease.

Independent risk factors for high-risk human papillomavirus infection among rural women in Shanxi Province, China: a population-based, case-control study

OBJECTIVE

Persistent high-risk human papillomavirus (hrHPV) infection is associated with most cervical cancers. This study aims to investigate the prevalence of and independent risk factors for hrHPV infection among women residing in rural areas of Shanxi Province, China.

METHODS

Data from the records of the cervical cancer screening programs for rural women in Shanxi Province were retrospectively collected. Women receiving primary HPV screening between January 2014 and December 2019 were included. The detection rate of hrHPV was calculated, and the independent risk factors for hrHPV infection were analyzed by multivariate logistic regression.

RESULTS

Among the women included, the overall infection rate of hrHPV was 14.01% (15,605/111,353), with the top five subtypes being HPV16 (24.79%), HPV52 (14.04%), HPV58 (10.26%), HPV18 (7.25%), and HPV53 (5.00%). The independent risk factors for hrHPV infection were specific geographical regions, testing years, older age, lower education level, inadequate previous screening, bacterial vaginosis, trichomonas vaginitis, and cervical polyps.

CONCLUSION

Rural women over 40 years of age, especially those who had never received screening, have a significantly increased risk for hrHPV infection and should be the target population with priority in cervical cancer screening.

Urogenital tract and rectal microbiota composition and its influence on reproductive outcomes in infertile patients

Introduction

Microbiota in the human body are closely related to human diseases. Female urogenital tract and rectal microbes have been considered as important factors affecting female pregnancy, but the mechanism is unknown.

Methods

Cervical, vaginal, urethral, and rectal swabs were collected from 22 infertile patients and 10 controls, and follicular fluid was extracted from 22 infertile patients. The microbial composition of different sampling sites of infertile patients was examined. By comparing the microbial composition difference between infertile patients and controls and combining bioinformatics methods to analyze the potential impact of the female urogenital tract (cervical, vaginal and urethral) and rectal microbial diversity on female infertility and pregnancy outcomes.

Results

Lactobacillus predominated in the female urogenital tract, but its abundance decreased in infertile patients, whereas the abundance of Gardnerella and Atopobium increased. The microbial changes in the urethra had the same trend as that in the vagina. Compared with healthy controls, the cervical and rectal microbial diversity of infertile patients were significantly increased and decreased, respectively. There might be interactions between microbes in different parts of female. Geobacillus thermogeniticans was enriched in the urogenital tract and rectum of infertile patients, and has a good predictive effect on infertility. Compared with infertile patients, L. johnsonii was enriched in the vagina, urethra, and intestine of the control group. L. acidophilus in follicular fluid might be associated with Non-pregnancy.

Conclusion

This study found that the microbial composition of infertile patients was changed compared with that of healthy people. The translocation of Lactobacillus between the rectum and urogenital tract might play a protective barrier role. The changes of Lactobacillus and Geobacillus might be related to female infertility or pregnancy outcome. The study provided a theoretical basis for the future treatment of female infertility from the perspective of microorganisms by detecting the microbial changes associated with female infertility.

The Intratumoral Bacterial Metataxonomic Signature of Hepatocellular Carcinoma

Microbiota is implicated in hepatocellular carcinoma (HCC). The spectrum of intratumoral microbiota associated with HCC progression remains elusive. Fluorescence in situ hybridization revealed that microbial DNAs were distributed in the cytosol of liver hepatocytes and erythrocytes. Viable anaerobic or aerobic bacteria were recovered in HCC tissues by fresh tissue culture. We performed a comprehensive DNA sequencing of bacterial 16S rRNA genes in 156 samples from 28 normal liver, 64 peritumoral, and 64 HCC tissues, and the DNA sequencing yielded 4.2 million high-quality reads. Both alpha and beta diversity in peritumor and HCC microbiota were increased compared to normal controls. The most predominant phyla in HCC were Patescibacteria, Proteobacteria, Bacteroidota, Firmicutes, and Actinobacteriota. phyla of Proteobacteria, Firmicutes, and Actinobacteriota, and classes of Bacilli and Actinobacteria, were consistently enriched in peritumor and HCC tissues, while Gammaproteobacteria was especially abundant in HCC tissues compared to normal controls. Streptococcaceae and Lactococcus were the marker taxa of HCC cirrhosis. The Staphylococcus branch and Caulobacter branch were selectively enriched in HBV-negative HCCs. The abundance of Proteobacteria, Gammaproteobacteria, Firmicutes, Actinobacteriota, and Saccharimonadia were associated with the clinicopathological features of HCC patients. The inferred functions of different taxa were changed between the microbiota of normal liver and peritumor/HCC. Random forest machine learning achieved great discriminative performance in HCC prediction (area under the curve [AUC] = 1.00 in the training cohort, AUC = 0.950 for top five class signature, and AUC = 0.943 for the top 50 operational taxonomy units [OTUs] in the validation cohort). Our analysis highlights the complexity and diversity of the liver and HCC microbiota and established a specific intratumoral microbial signature for the potential prediction of HCC. IMPORTANCE Gut microbiome is an important regulator of hepatic inflammation, detoxification, and immunity, and contributes to the carcinogenesis of liver cancer. Intratumoral bacteria are supposed to be closer to the tumor cells, forming a microenvironment that may be relevant to the pathological process of hepatocellular carcinoma (HCC). However, the presence of viable intratumoral bacteria remains unclear. It is worth exploring whether the metataxonomic characteristics of intratumoral bacteria can be used as a potential marker for HCC prediction. Here, we present the first evidence of the existence of viable intratumoral bacteria in HCC using the tissue culture method. We revealed that microbial DNAs were distributed in the cytosol of liver hepatocytes and erythrocytes. We analyzed the diversity, structure, and abundance of normal liver and HCC microbiota. We built a machine learning model for HCC prediction using intratumoral bacterial features. We show that specific taxa represent potential targets for both therapeutic and diagnostic interventions.

Distribution of microbiota in cervical preneoplasia of racially disparate populations

BACKGROUNDS

Microbiome dysbiosis is an important contributing factor in tumor development and thus may be a risk predictor for human malignancies. In the United States, women with Hispanic/Latina (HIS) and African American (AA) background have a higher incidence of cervical cancer and poorer outcomes than Caucasian American (CA) women.

METHODS

Here, we assessed the distribution pattern of microbiota in cervical intraepithelial neoplasia (CIN) lesions obtained from HIS (n = 12), AA (n = 12), and CA (n = 12) women, who were screened for CC risk assessment. We employed a 16S rRNA gene sequencing approach adapted from the NIH-Human Microbiome Project to identify the microbial niche in all CIN lesions (n = 36).

RESULTS

We detected an appreciably decreased abundance of beneficial Lactobacillus in the CIN lesions of the AA and HIS women compared to the CA women. Differential abundance of potentially pathogenic Prevotella, Delftia, Gardnerella, and Fastidiosipila was also evident among the various racial groups. An increased abundance of Micrococcus was also evident in AA and HIS women compared to the CA women. The detection level of Rhizobium was higher among the AA ad CA women compared to the HIS women. In addition to the top 10 microbes, a unique niche of 27 microbes was identified exclusively in women with a histopathological diagnosis of CIN. Among these microbes, a group of 8 microbiota; Rubellimicrobium, Podobacter, Brevibacterium, Paracoccus, Atopobium, Brevundimonous, Comamonous, and Novospingobium was detected only in the CIN lesions obtained from AA and CA women.

CONCLUSIONS

Microbial dysbiosis in the cervical epithelium represented by an increased ratio of potentially pathogenic to beneficial microbes may be associated with increased CC risk disparities. Developing a race-specific reliable panel of microbial markers could be beneficial for CC risk assessment, disease prevention, and/or therapeutic guidance.

In-depth insights into cervicovaginal microbial communities and hrHPV infections using high-resolution microbiome profiling

The cervicovaginal microbiome (CVM) correlates with women's cervical health, and variations in its composition are associated with high-risk human papillomavirus (hrHPV) infection outcomes. Cervicovaginal microbes have been grouped into five community state types (CSTs) based on microbial community composition and abundance. However, studying the impact of CSTs in health and disease is challenging because the current sequencing technologies have limited confident discrimination between closely related and yet functionally different bacterial species. Circular probe-based RNA sequencing (ciRNAseq) achieves high-resolution microbiome profiling and therefore provides in-depth and unambiguous knowledge about the composition of the CVM. Based on ciRNAseq profiling of a large cohort of cervical smears (n = 541), we here define subgroups of CSTs I, III, and IV based on intra-CST differences with respect to abundances of Lactobacillus acidophilus (CSTs I-A vs. I-B and CSTs III-A vs. III-B), Lactobacillus iners (CSTs I-A vs. I-B and CSTs III-A vs. III-B), and Megasphaera genomosp type 1 (CSTs IV-A vs. IV-B). Our results further support the existence of subgroups of CST IV-C that are dominant for non-Lactobacillus species and have intermediate microbial diversity. We also show that CST V is associated with uninfected conditions, and CST IV-A associates with hrHPV-induced cervical disease. In conclusion, we characterized new subdivisions of cervicovaginal CSTs, which may further advance our understanding of women's cervical health and hrHPV-related progression to disease.

BV associated bacteria specifically BVAB 1 and BVAB 3 as biomarkers for HPV risk and progression of cervical neoplasia

Background

Bacterial vaginosis (BV) is associated with high-risk HPV (hrHPV) genotypes. There is a proposed bidirectional relationship between hrHPV and vaginal microbial diversity. This study investigated the association between BV associated bacteria in women co-infected with Human immunodeficiency virus (HIV) and hrHPV.

Methods

Stored cervical cytobrush samples were used for real time PCR detection of eight BV associated bacteria. Analysis of BV bacteria detected against HPV infection, socio-demographics and HIV data were conducted in R Statistical computing software of the R Core Team, 2020, version 3.6.3.

Results

A total of 190 samples were analysed. A. vaginae (p <0.001) BVAB 1 (p <0.001), BVAB 2 (p =0.428), BVAB 3 (p <0.001), Lactobacillus species (p =0.016) and S. sanguinegens (p =0.007) were associated with prevalent hrHPV. Increasing CIN severity was independently associated with detection of BVAB 1 OR 1.51(95% CI: 0.42-5.55), BVAB 3 OR 2.72(95% CI:0.90-8.55) and S. sanguinegens OR 1.02(95% CI:0.37-2.80). All HPV genotypes/groups, gravida <2, A. vaginae (p =0.002) and BVAB 1 (p =0.026) were significantly associated with HPV persistence. BVAB 3, p =0.010 and HPV 16 were significantly associated with HPV reinfection.

Conclusion

There is a significant association of A. vaginae, BVAB 1, BVAB 3, S. sanguinegens and Lactobacillus spp to prevalent hrHPV. BVAB 1, BVAB 3 and S. sanguinegens had an increased odds for increasing CIN severity. A vaginae, BVAB 1, gravida and all the HPV genotypes/groups were significantly associated with HPV persistence. Only BVAB 3 and HPV 16 were significantly associated with hrHPV reinfection at 1 year review. BVAB 1 and BVAB 3 are possible biomarkers for HPV infection and CIN progression.

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.

Genital Microbiota of Women From Six Ethnic Groups With and Without Human Papillomavirus Infection in Shangri-La, China

Background

A diversity of microorganisms is associated with human health and exists in a state of dynamic equilibrium. This diversity has direct implications for the assessment of susceptibility to infectious diseases, especially human papillomavirus (HPV) infection.

Methods

Here, we investigated the relationships between HPV infection and vaginal, cervical, and gut microbiota composition and assessed the levels of genital immune mediators. We selected a multiethnic area in Yunnan Province, China, to collect samples from healthy women of childbearing age. A total of 82 healthy women of childbearing age were included in this study. Vaginal, cervical, and rectal swabs were collected to analyze the microbial community, and cytokines were analyzed in some samples.

Findings

Different proportions and types of HPV infection were detected in cervical (44%), vaginal (18%), and rectal (18%) swabs. HPV detected in cervical swabs was generally a high-risk type, while low-risk HPV types were primarily detected in vaginal and rectal swabs. There were some differences in this proportion as well as in the microbial community composition among different ethnic groups. Rectal samples exhibited the highest diversity index, while vaginal samples displayed the lowest diversity index. Lactobacillus dominated most of the vaginal samples, was decreased in HPV-positive samples, and differed among different ethnic groups. However, the sequence proportion of Lactobacillus in the cervix exhibited the opposite trend in those affected by HPV infection. The dynamic balance between the potential pathogens Gardnerella and Lactobacillus determines the health of the female genital system.

Interpretation

This study constitutes the first step toward personalized medicine for women’s reproductive health, wherein differences between the genital microbiomes of individuals would be considered in risk assessment and for subsequent disease diagnosis and treatment.

The Diversity of Vaginal Microbiota Predicts Neoadjuvant Chemotherapy Responsiveness in Locally Advanced Cervical Cancer

The vaginal microbiota is closely related to HPV infection and cervical cancer (CC), but its relationship with platinum-based chemotherapy responsiveness is unknown. The study aimed to investigate the vaginal microbiota diversity of women with locally advanced cervical cancer (LACC) and compare the differences between responders and nonresponders. We characterized the 16S rRNA gene sequencing of vaginal microbiome of 66 vaginal samples, including 26 LACC patients before neoadjuvant chemotherapy and 40 healthy controls. Compared with the healthy controls, alpha diversity was significantly increased in CC patients (p <0.05) with more unconventionality bacterial colonization. Beta diversity also significantly differed between cervical cancer patients and controls (p <0.01). Within the CC patients, alpha diversity in vaginal samples was significantly higher in the nonresponders versus the responders (p <0.01), and the Ace index and Chao index were negatively correlated with mass reduction (p <0.001). Moreover, the Bacteroides genus enriched in the nonresponders had a ROC-plot AUC value reaching 0.84. The study suggests the vaginal microbiota in LACC patients is associated with platinum-based chemotherapy responsiveness. Alpha diversity and Bacteroides abundance have the potential of identifying platinum-resistant patients at an early time. These findings provide a basis for further research on the relationship between vaginal microbiome and chemotherapy effect in LACC.

Exploring the Association Between Cervical Microbiota and HR-HPV Infection Based on 16S rRNA Gene and Metagenomic Sequencing

The relationship between the cervico-vaginal microbiome and high-risk human papillomavirus (HR-HPV) is well observed. However, there is a lack of adequate research regarding the cervical microbiota in HR-HPV infection. Most published research results have used 16S rRNA gene sequencing technology; this technology only focuses on marker sequences, resulting in incomplete gene information acquisition. Metagenomic sequencing technology can effectively compensate for the deficiency of 16S rRNA gene sequencing, thus improving the analysis of microbiota function. Cervical swab samples from 20 females with HR-HPV infection and 20 uninfected (Control) women were analyzed through 16S rRNA gene and metagenomic sequencing. Our results indicated that the composition and function of the cervical microbiota of HR-HPV infection differed notably from that of control women. Compared with control women, Firmicutes was decreased during HR-HPV infection, whereas Actinobacteria was increased. At the genus level, Lactobacillus was enriched in control women, while levels of Gardnerella and Bifidobacterium were lower. At the species level, Lactobacillus crispatus, L. jensenii, and L. helveticus were enriched in control women; these were the top three species with biomarker significance between the two groups. Eight pathways and four KEGG orthologies of the cervical microbiota of statistical differences were identified between the HR-HPV infection and control women. Collectively, our study described the cervical microbiota and its potential function during HR-HPV infection. Biomarkers of cervical microbiota and the changed bacterial metabolic pathways and metabolites can help clarify the pathogenic mechanism of HR-HPV infection, making them promising targets for clinical treatment and intervention for HR-HPV infection and cervical carcinoma.

Implications of Gut Microbiota in Epithelial-Mesenchymal Transition and Cancer Progression: A Concise Review

Advancement in the development of molecular sequencing platforms has identified infectious bacteria or viruses that trigger the dysregulation of a set of genes inducing the epithelial-mesenchymal transition (EMT) event. EMT is essential for embryogenesis, wound repair, and organ development; meanwhile, during carcinogenesis, initiation of the EMT can promote cancer progression and metastasis. Recent studies have reported that interactions between the host and dysbiotic microbiota in different tissues and organs, such as the oral and nasal cavities, esophagus, stomach, gut, skin, and the reproductive tract, may provoke EMT. On the other hand, it is revealed that certain microorganisms display a protective role against cancer growth, indicative of possible therapeutic function. In this review, we summarize recent findings elucidating the underlying mechanisms of pathogenic microorganisms, especially the microbiota, in eliciting crucial regulator genes that induce EMT. Such an approach may help explain cancer progression and pave the way for developing novel preventive and therapeutic strategies.

Modelling Chlamydia and HPV co-infection in patient-derived ectocervix organoids reveals distinct cellular reprogramming

Coinfections with pathogenic microbes continually confront cervical mucosa, yet their implications in pathogenesis remain unclear. Lack of in-vitro models recapitulating cervical epithelium has been a bottleneck to study coinfections. Using patient-derived ectocervical organoids, we systematically modeled individual and coinfection dynamics of Human papillomavirus (HPV)16 E6E7 and Chlamydia, associated with carcinogenesis. The ectocervical stem cells were genetically manipulated to introduce E6E7 oncogenes to mimic HPV16 integration. Organoids from these stem cells develop the characteristics of precancerous lesions while retaining the self-renewal capacity and organize into mature stratified epithelium similar to healthy organoids. HPV16 E6E7 interferes with Chlamydia development and induces persistence. Unique transcriptional and post-translational responses induced by Chlamydia and HPV lead to distinct reprogramming of host cell processes. Strikingly, Chlamydia impedes HPV-induced mechanisms that maintain cellular and genome integrity, including mismatch repair in the stem cells. Together, our study employing organoids demonstrates the hazard of multiple infections and the unique cellular microenvironment they create, potentially contributing to neoplastic progression.

Here, Koster et al., model human papillomavirus and Chlamydia coinfection dynamics in patient-derived ectocervical organoids, and characterize the effects of multiple infections in the cellular microenvironment, potentially contributing to neoplasia.

Multi-omics data integration reveals metabolome as the top predictor of the cervicovaginal microenvironment

Emerging evidence suggests that host-microbe interaction in the cervicovaginal microenvironment contributes to cervical carcinogenesis, yet dissecting these complex interactions is challenging. Herein, we performed an integrated analysis of multiple "omics" datasets to develop predictive models of the cervicovaginal microenvironment and identify characteristic features of vaginal microbiome, genital inflammation and disease status. Microbiomes, vaginal pH, immunoproteomes and metabolomes were measured in cervicovaginal specimens collected from a cohort (n = 72) of Arizonan women with or without cervical neoplasm. Multi-omics integration methods, including neural networks (mmvec) and Random Forest supervised learning, were utilized to explore potential interactions and develop predictive models. Our integrated analyses revealed that immune and cancer biomarker concentrations were reliably predicted by Random Forest regressors trained on microbial and metabolic features, suggesting close correspondence between the vaginal microbiome, metabolome, and genital inflammation involved in cervical carcinogenesis. Furthermore, we show that features of the microbiome and host microenvironment, including metabolites, microbial taxa, and immune biomarkers are predictive of genital inflammation status, but only weakly to moderately predictive of cervical neoplastic disease status. Different feature classes were important for prediction of different phenotypes. Lipids (e.g. sphingolipids and long-chain unsaturated fatty acids) were strong predictors of genital inflammation, whereas predictions of vaginal microbiota and vaginal pH relied mostly on alterations in amino acid metabolism. Finally, we identified key immune biomarkers associated with the vaginal microbiota composition and vaginal pH (MIF), as well as genital inflammation (IL-6, IL-10, MIP-1α).

Preliminary Identification of the Aerobic Cervicovaginal Microbiota in Mexican Women With Cervical Cancer as the First Step Towards Metagenomic Studies

Cervical cancer (CC) is considered a public health problem. Recent studies have evaluated the possible relationship between the cervicovaginal microbiome and gynecologic cancer but have not studied the relationship between aerobic bacterial communities and neoplasia. The study aimed to identify the cultivable aerobic bacterial microbiota in women with cervical cancer as a preliminary approach to the metagenomic study of the cervicovaginal microbiome associated with cervical cancer in Mexican women. An observational cross-sectional study was conducted, including 120 women aged 21-71 years, divided into two study groups, women with locally advanced CC (n=60) and women without CC (n=60). Sociodemographic, gynecological-obstetric, sexual, and habit data were collected. Cervicovaginal samples were collected by swabbing, from which standard microbiological methods obtained culturable bacteria. The strains were genetically characterized by PCR-RFLP of the 16S rRNA gene and subsequently identified by sequencing the same gene. Variables regularly reported as risk factors for the disease were found in women with CC. Differences were found in the prevalence and number of species isolated in each study group. Bacteria commonly reported in women with aerobic vaginitis were identified. There were 12 species in women with CC, mainly Corynebacterium spp. and Staphylococcus spp.; we found 13 bacterial species in the group without cancer, mainly Enterococcus spp. and Escherichia spp. The advanced stages presented a more significant number of isolates and species. This study provided a preliminary test for cervicovaginal metagenomic analysis, demonstrating the presence of aerobic cervicovaginal dysbiosis in women with CC and the need for more in-depth studies.

Novel high-resolution targeted sequencing of the cervicovaginal microbiome

BACKGROUND

The cervicovaginal microbiome (CVM) plays a significant role in women's cervical health and disease. Microbial alterations at the species level and characteristic community state types (CST) have been associated with acquisition and persistence of high-risk human papillomavirus (hrHPV) infections that may result in progression of cervical lesions to malignancy. Current sequencing methods, especially most commonly used multiplex 16S rRNA gene sequencing, struggle to fully clarify these changes because they generally fail to provide sufficient taxonomic resolution to adequately perform species-level associative studies. To improve CVM species designation, we designed a novel sequencing tool targeting microbes at the species taxonomic rank and examined its potential for profiling the CVM.

RESULTS

We introduce an accessible and practical circular probe-based RNA sequencing (CiRNAseq) technology with the potential to profile and quantify the CVM. In vitro and in silico validations demonstrate that CiRNAseq can distinctively detect species in a mock mixed microbial environment, with the output data reflecting its ability to estimate microbes' abundance. Moreover, compared to 16S rRNA gene sequencing, CiRNAseq provides equivalent results but with improved sequencing sensitivity. Analyses of a cohort of cervical smears from hrHPV-negative women versus hrHPV-positive women with high-grade cervical intraepithelial neoplasia confirmed known differences in CST occurring in the CVM of women with hrHPV-induced lesions. The technique also revealed variations in microbial diversity and abundance in the CVM of hrHPV-positive women when compared to hrHPV-negative women.

CONCLUSIONS

CiRNAseq is a promising tool for studying the interplay between the CVM and hrHPV in cervical carcinogenesis. This technology could provide a better understanding of cervicovaginal CST and microbial species during health and disease, prompting the discovery of biomarkers, additional to hrHPV, that can help detect high-grade cervical lesions.

The vaginal microbiota and innate immunity after local excisional treatment for cervical intraepithelial neoplasia

BACKGROUND

Vaginal microbiota (VMB) composition is altered in women with cervical intra-epithelial neoplasia (CIN) compared to healthy controls and is associated with disease progression. However, the impact of CIN excision on the VMB and innate immunity is not known. This observational study aims to explore the impact of CIN excision on the VMB, antimicrobial peptides (AMP) and proinflammatory cytokines.

METHODS

We sampled 103 non-pregnant, premenopausal women at the time of excisional treatment for CIN and at their 6-month follow-up visit. A further 39 untreated controls with normal cytology were also sampled. We used metataxonomics to group vaginal swab samples into community state types (CSTs) and ELISA to quantify cytokine and AMP levels in matched vaginal secretions. Analyses were performed to compare the bacterial composition and immune analyte levels before and after CIN excision and in healthy controls.

RESULTS

Women with CIN had significantly higher rates of Lactobacillus species depletion pre-treatment compared to healthy controls (CST IV 21/103, 20% vs 1/39, 3%, p = 0.0081). Excision did not change the VMB composition, with CST IV remaining significantly more prevalent after excision compared to untreated, healthy controls (CST IV 19/103, 20% vs 1/39, 3%, p = 0.0142). Prevotella bivia and Sneathia amnii were significantly higher in samples before treatment compared to untreated controls, and Prevotella bivia remained significantly higher amongst the treated, with less Lactobacillus crispatus compared to untreated controls. IL-1β and IL-8 remained significantly elevated pre- (p < 0.0001 and p = 0.0014, respectively) and post-treatment (p < 0.0001 and p = 0.0035, respectively) compared to untreated controls. Levels of human beta-defensin-1 and secretory leukocyte protease inhibitor were both significantly reduced following CIN excision (p < 0.0001); however, their levels remained lower than controls post-treatment.

CONCLUSIONS

Women with CIN have an increased prevalence of Lactobacillus sp. depletion, high-diversity VMB composition, and higher levels of proinflammatory cytokines and AMPs compared to normal controls. Surgical excision of the disease reduces levels of vaginal AMPs but does not alter VMB composition or cytokine levels. These findings suggest that women with CIN have an inherent predisposition to a high-diversity proinflammatory environment that is not corrected by disease excision. The failure to re-establish a Lactobacillus-enriched CST may explain why women remain at high risk of pre-invasive and invasive disease recurrence.

Changes in the diversity of local cervical bacteria in women with cervical cancer receiving antineoplastic treatment

Background

Some studies show changes in the microbiota in people undergoing antineoplastic treatment. Currently, there is not enough evidence of this effect in the treatment of cervical cancer (CC). The objective was to determine changes in the diversity of local cervical bacteria in women with CC receiving chemotherapy, radiotherapy, and brachytherapy.

Materials and Methods

A descriptive, longitudinal, and prospective study was conducted in 68 women with locally advanced CC with a treatment plan based on the administration of chemotherapy, external beam radiotherapy, and brachytherapy. Cervical-vaginal fluid samples were taken during antineoplastic treatment. The samples were used to isolate bacterial strains. The bacteria were identified at the molecular level by comparing sequences of the 16S ribosomal RNA gene.

Results

The bacteria identified belonged to three phyla: Firmicutes, Proteobacteria, and Actinobacteria. Nine genera and 25 species of bacteria were identified. The most frequent species were Staphylococcus epidermidis, Corynebacterium amycolatum, and Enterococcus faecalis. There were statistically significant differences when comparing bacterial diversity found in the different stages of treatment (≤0.05). Bacterial diversity decreased as antineoplastic treatment progressed and increased at the end of therapy.

Conclusion

Antineoplastic treatments generate changes in the diversity of local cervical bacterial communities of women with CC.

Comparative measurement of D- and L-lactic acid isomers in vaginal secretions: association with high-grade cervical squamous intraepithelial lesions

PURPOSE

Identification of low-cost protocols to identify women at elevated susceptibility to develop cervical intra-epithelial abnormalities would aid in more individualized monitoring. We evaluated whether quantitation of the D- and L-lactic acid isomers in vaginal secretions could differentiate women with normal cervical epithelia from those with a low (LSIL) or high (HSIL) grade squamous intraepithelial lesion or with cervical cancer.

METHODS

Vaginal samples, collected from 78 women undetgoing cervical colposcopy and biopsy, were tested for pH, bacterial composition by Gram stain (Nugent score) and concentrations of D- and L-lactic acid by a colorimetric assay.

RESULTS

Subsequent diagnosis was 23 women with normal cervical epithelium, 10 with LSIL, 43 with HSIL and 2 with cervical cancer. Vaginal pH and Nugent score were comparable in all subject groups. The concentration of L-lactic acid, but not D-lactic acid, as well as the L/D-lactic acid ratio, were significantly elevated (p < 0.01) in women with HSIL and cervical cancer.

CONCLUSION

Comparative measurement of vaginal D- and L-lactic acid isomers may provide a low-cost alternative to identification of women with an elevated susceptibility to cervical abnormalities.

The Application of High-Throughput Technologies for the Study of Microbiome and Cancer

Human gut microbiome research, especially gut microbiome, has been developing at a considerable pace over the last decades, driven by a rapid technological advancement. The emergence of high-throughput technologies, such as genomics, transcriptomics, and others, has afforded the generation of large volumes of data, and in relation to specific pathologies such as different cancer types. The current review identifies high-throughput technologies as they have been implemented in the study of microbiome and cancer. Four main thematic areas have emerged: the characterization of microbial diversity and composition, microbial functional analyses, biomarker prediction, and, lastly, potential therapeutic applications. The majority of studies identified focus on the microbiome diversity characterization, which is reaching technological maturity, while the remaining three thematic areas could be described as emerging.

A Framework for Cervical Cancer Elimination in Low-and-Middle-Income Countries: A Scoping Review and Roadmap for Interventions and Research Priorities

The World Health Organization announced an ambitious call for cervical cancer elimination worldwide. With existing prevention and treatment modalities, cervical cancer elimination is now within reach for high-income countries. Despite limited financing and capacity constraints in low-and-middle-income countries (LMICs), prevention and control efforts can be supported through integrated services and new technologies. We conducted this scoping review to outline a roadmap toward cervical cancer elimination in LMICs and highlight evidence-based interventions and research priorities to accelerate cervical cancer elimination. We reviewed and synthesized literature from 2010 to 2020 on primary and secondary cervical cancer prevention strategies. In addition, we conducted expert interviews with gynecologic and infectious disease providers, researchers, and LMIC health officials. Using these data, we developed a logic model to summarize the current state of science and identified evidence gaps and priority research questions for each prevention strategy. The logic model for cervical cancer elimination maps the needs for improved collaboration between policy makers, production and supply, healthcare systems, providers, health workers, and communities. The model articulates responsibilities for stakeholders and visualizes processes to increase access to and coverage of prevention methods. We discuss the challenges of contextual factors and highlight innovation needs. Effective prevention methods include HPV vaccination, screening using visual inspection and HPV testing, and thermocoagulation. However, vaccine coverage remains low in LMICs. New strategies, including single-dose vaccination could enhance impact. Loss to follow-up and treatment delays could be addressed by improved same-day screen-and-treat technologies. We provide a practical framework to guide cervical cancer elimination in LMICs. The scoping review highlights existing and innovative strategies, unmet needs, and collaborations required to achieve elimination across implementation contexts.

Comparative genome analyses of Lactobacillus crispatus isolated from different ecological niches reveal an environmental adaptation of this species to the human vaginal environment

Vaginal microbiota is defined as the community of bacteria residing in the human vaginal tract. Recent studies have demonstrated that the vaginal microbiota is dominated by members of the Lactobacillus genus, whose relative abundance and microbial taxa composition are dependent on the healthy status of this human body site. Particularly, among members of this genus, the high prevalence of Lactobacillus crispatus is commonly associated with a healthy vaginal environment. In the current study, we assessed the microbial composition of 94 healthy vaginal microbiome samples through shotgun metagenomics analyses. Based on our results we observed that L. crispatus was the most representative species and correlated negatively with bacteria involved in vaginal infections. Therefore, we isolated fifteen L. crispatus strains from different environments in which this species is abounding, ranging from vaginal swabs of healthy women to chicken fecal samples. The genomes of these strains were decoded and their genetic content was analyzed and correlated with their physiological features. An extensive comparative genomic analysis encompassing all publicly available genome sequences of L. crispatus and combined with those decoded in this study, revealed a genetic adaptation of strains to their ecological niche. In addition, in vitro growth experiments involving all isolated L. crispatus strains together with a synthetic vaginal microbiota reveal how this species is able to modulate the composition of the vaginal microbial consortia at strain level. Overall, our findings suggest that L. crispatus plays an important ecological role in reducing the complexity of the vaginal microbiota by depleting pathogenic bacteria.Importance The vaginal microbiota is defined as the community of bacteria residing in the human vaginal tract. Recent studies have demonstrated that the high prevalence of Lactobacillus crispatus species is commonly associated with a healthy vaginal environment. In the current study, we assessed the microbial composition of 94 public healthy vaginal samples through shotgun metagenomics analyses. Results showed that L. crispatus was the most representative species and correlated negatively with bacteria involved in vaginal infections. Moreover, we isolated and sequenced the genome of new L. crispatus strains from different environments and the comparative genomics analysis revealed a genetic adaptation of strains to their ecological niche. In addition, in-vitro growth experiments display the capability of this species to modulate the composition of the vaginal microbial consortia. Overall, our findings suggest an ecological role exploited by L. crispatus in reducing the complexity of the vaginal microbiota toward a depletion of pathogenic bacteria.

Complete genome sequencing of Peyer's patches-derived Lactobacillus taiwanensis CLG01, a potential probiotic with antibacterial and immunomodulatory activity

Background

The genus Lactobacillus is an important component of the gastrointestinal tract of human and animals and commonly considered as probiotic. L. taiwanensis has long been proposed to be a probiotic whereas understanding on this species is still in its infancy. Genomic information of L. taiwanensis is fairly limited. Extensive characterization of its beneficial traits is needed.

Results

A new strain CLG01 of L. taiwanensis was isolated from mouse Peyer’s patches. We established its probiotic profile through in vitro experiments. Complete genome of this strain was also sequenced and analyzed. L. taiwanensis CLG01 showed robust tolerance to acid and a degree of tolerance to bile salt with a promising antibacterial activity against a broad spectrum of pathogenic bacteria. In vitro treatment of mouse RAW 264.7 macrophage cells with heat-killed bacteria and bacterial supernatant of L. taiwanensis CLG01 resulted in enhancement of immune responses and upregulated expression of TNF-α and IL-6. The strain CLG01 also increased the IL-10 production of macrophages when co-treated with lipopolysaccharide (LPS). Complete genome of L. taiwanensis CLG01 contained a 1.89 Mb chromosome and two plasmids. Further genomic analysis revealed the presence of genes related to its resistance to different stresses and the beneficial effects mentioned above. Moreover, biosynthetic gene clusters (BGCs) encoding antimicrobial peptides, like bacteriocin, linear azol(in)e-containing peptide (LAP) and lanthipeptide, were also identified in the genome of L. taiwanensis CLG01.

Conclusions

L. taiwanensis CLG01, isolated from mouse Peyer’s patches, is the first L. taiwanensis strain with both phenotypes and genotypes systematically studied. These preliminary data confirmed the role of L. taiwanensis CLG01 as a potential probiotic candidate with antibacterial and immunomodulatory activity, which provide insight for further investigation to this species.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12866-021-02127-z.

Influence of Pelvic Intensity-Modulated Radiation Therapy With Concurrent Cisplatin-Based Chemotherapy of Cervical Cancer on the Vaginal Microbiome

Pelvic intensity-modulated radiation therapy (IMRT) combined with concurrent chemotherapy is an effective treatment for cervical cancer; however, radiation resistance impairs its clinical benefit. The vaginal microbiome plays an important but poorly understood role in cancer radiochemotherapy. In this study, we investigated the effects of treatment on the overall composition and alteration of the vaginal microbiome in patients receiving pelvic IMRT with concurrent cisplatin-based chemotherapy. We collected samples from twenty patients with cervical cancer and six healthy controls and performed 16S rRNA sequencing. Vaginal microbial composition analysis revealed significant differences between the two groups, but no significant differences between radiation treatment time points. However, the relative abundances of Gammaproteobacteria, Gemmatimonadetes, Gemmatimonadales, Pseudomonadales, Gemmatimonadaceae, Rikenellaceae, Acinetobacter, Desulfovibrio, Prevotella 9, Rikenellaceae RC9 gut group, Turicibacter, and the metagenome increased with time. The results encourage further study into the effects of the vaginal microbiome on cervical cancer treatment strategies, especially radiochemotherapy. Better understanding of these effects could inform new therapeutic approaches to enhance the efficacy of radiochemotherapy.

Revealing the Disturbed Vaginal Micobiota Caused by Cervical Cancer Using High-Throughput Sequencing Technology

Cervical cancer is the fourth most prevalent cancer type among all malignancies, so it is of great significance to find its actual pathogenesis mechanisms. In the present study, 90 women were enrolled, and high-throughput sequencing technology was firstly used to analyze the vaginal microbiota of healthy women (C group), cervical intraepithelial neoplasia patients (CIN group) and cervical cancer patients (CER group). Our results indicates that compared with C group, a higher HPV infection rate as well as increased Neutrophil ratio and tumor marker squamous cell carcinoma antigen (SCCA) were obtained, and a decrease in Lymphocyte ratio and Hemoglobin were also present. In addition, the cervical cancer showed a strong association with reduced probiotics Lactobacillus, increased pathogens Prevotella spp., Sneathia spp. and Pseudomonas spp. These results prove that the immunological changes generated by the cervical cancer and the vaginal microbiota can interact with each other. However, further study investigating the key bacteria for cervical cancer is still needed, which can be a clue for the diagnosis or treatment of cervical cancer.

Dual and mutual interaction between microbiota and viral infections: a possible treat for COVID-19

All of humans and other mammalian species are colonized by some types of microorganisms such as bacteria, archaea, unicellular eukaryotes like fungi and protozoa, multicellular eukaryotes like helminths, and viruses, which in whole are called microbiota. These microorganisms have multiple different types of interaction with each other. A plethora of evidence suggests that they can regulate immune and digestive systems and also play roles in various diseases, such as mental, cardiovascular, metabolic and some skin diseases. In addition, they take-part in some current health problems like diabetes mellitus, obesity, cancers and infections. Viral infection is one of the most common and problematic health care issues, particularly in recent years that pandemics like SARS and COVID-19 caused a lot of financial and physical damage to the world. There are plenty of articles investigating the interaction between microbiota and infectious diseases. We focused on stimulatory to suppressive effects of microbiota on viral infections, hoping to find a solution to overcome this current pandemic. Then we reviewed mechanistically the effects of both microbiota and probiotics on most of the viruses. But unlike previous studies which concentrated on intestinal microbiota and infection, our focus is on respiratory system's microbiota and respiratory viral infection, bearing in mind that respiratory system is a proper entry site and residence for viruses, and whereby infection, can lead to asymptomatic, mild, self-limiting, severe or even fatal infection. Finally, we overgeneralize the effects of microbiota on COVID-19 infection. In addition, we reviewed the articles about effects of the microbiota on coronaviruses and suggest some new therapeutic measures.

Microbiome and Cervical Cancer

Persistent infection with some types of mucosal human papillomavirus (HPV) is the etiological factor for the development of cervical cancer and its precursor lesions. Besides, several cofactors are known to play a role in cervical disease onset and progression either by favoring or by preventing HPV infection and persistence. The microbiome of a healthy female genital tract is characterized by the presence of 1 or few varieties of lactobacilli. However, high-throughput studies addressing the bacterial diversity and abundance in the female genital tract have shown that several factors, including hormonal levels, hygiene habits, and sexually transmitted diseases may disrupt the natural balance, favoring the outgrowth of some groups of bacteria, which in turn may favor some pathological states. Recently, the vaginal microbiome has emerged as a new variable that could greatly influence the natural history of HPV infections and their clinical impact. In this context, changes in the vaginal microbiome have been detected in women infected with HPV and women with HPV-associated lesions and cancer. However, the role of specific bacteria groups in the development/progression or prevention/regression of HPV-associated pathologies is not well understood. In this review we summarize the current knowledge concerning changes in vaginal microbiome and cervical disease. We discuss the potential functional interplay between specific bacterial groups and HPV infection outcomes.

Vaginal microbiota and the potential of Lactobacillus derivatives in maintaining vaginal health

Human vagina is colonised by a diverse array of microorganisms that make up the normal microbiota and mycobiota. Lactobacillus is the most frequently isolated microorganism from the healthy human vagina, this includes Lactobacillus crispatus, Lactobacillus gasseri, Lactobacillus iners, and Lactobacillus jensenii. These vaginal lactobacilli have been touted to prevent invasion of pathogens by keeping their population in check. However, the disruption of vaginal ecosystem contributes to the overgrowth of pathogens which causes complicated vaginal infections such as bacterial vaginosis (BV), sexually transmitted infections (STIs), and vulvovaginal candidiasis (VVC). Predisposing factors such as menses, pregnancy, sexual practice, uncontrolled usage of antibiotics, and vaginal douching can alter the microbial community. Therefore, the composition of vaginal microbiota serves an important role in determining vagina health. Owing to their Generally Recognised as Safe (GRAS) status, lactobacilli have been widely utilised as one of the alternatives besides conventional antimicrobial treatment against vaginal pathogens for the prevention of chronic vaginitis and the restoration of vaginal ecosystem. In addition, the effectiveness of Lactobacillus as prophylaxis has also been well-founded in long-term administration. This review aimed to highlight the beneficial effects of lactobacilli derivatives (i.e. surface-active molecules) with anti-biofilm, antioxidant, pathogen-inhibition, and immunomodulation activities in developing remedies for vaginal infections. We also discuss the current challenges in the implementation of the use of lactobacilli derivatives in promotion of human health. In the current review, we intend to provide insights for the development of lactobacilli derivatives as a complementary or alternative medicine to conventional probiotic therapy in vaginal health.

Vaginal Microbiota and Cytokine Microenvironment in HPV Clearance/Persistence in Women Surgically Treated for Cervical Intraepithelial Neoplasia: An Observational Prospective Study

High-risk human papillomaviruses (hrHPVs) are causally related to cervical intraepithelial neoplasia (CIN) and subsequent cervical cancer (CC). The vaginal microbiome has been suggested to play a role in the development of CC, but the effect of conservative surgical treatment on the microbiome and hrHPV elimination has not been elucidated. In this study, we aimed to characterize the vaginal microbiome and inflammatory chemokine profile in 85 women treated for CIN2-CIN3 lesions, before and after surgical CIN removal. The results showed, as expected, a high prevalence of dysbiotic microbiomes and vaginal pro-inflammatory cytokines in the CIN cohort, correlated with disease severity, at the basal level. By contrast, surgical CIN removal induced significant vaginal microbiome variations, and specific microbiome/cytokine profiles were associated with hrHPV clearance/persistence at 6-month follow-up. hrHPV-cleared patients, in fact, showed a specific increase of L. crispatus and decrease of dysbiosis and inflammatory cytokines compared to hrHPV-persistent patients. These data highlight the crosstalk between HPV and the local microbiome, and suggest that vaginal microbiome modulation might represent a novel approach to modifying the natural history of hrHPV-related CC.

Study registration n. ISRCTN34437150 (https://www.isrctn.com/ISRCTN34437150).

Changes of vaginal microbiota during cervical carcinogenesis in women with human papillomavirus infection

Objective

To evaluate the changes of vaginal microbiota during cervical carcinogenesis in women with high-risk human papillomavirus infection.

Materials and methods

Vaginal microbiota was analyzed using next-generation sequencing in women with normal, cervical intraepithelial neoplasia (CIN), or cervical cancer.

Results

A marked decrease of Lactobacillus crispatus was found in the CIN/cancer groups compared with that in the normal group. The diversity of microorganisms increased in patients with CIN or cervical cancer with HPV infection. Atopobium vaginae (OR 4.33, 95% CI 1.15–16.32), Dialister invisus (OR 4.89, 95% CI 1.20–19.94), Finegoldia magna (OR 6.00, 95% CI 1.08–33.27), Gardnerella vaginalis (OR 7.43, 95% CI 1.78–31.04), Prevotella buccalis (OR 11.00, 95% CI 2.00–60.57), and Prevotella timonensis (OR 6.00, 95% CI 1.46–24.69) were significantly associated with the risk of CIN 2/3 or cervical cancer.

Conclusion

Women with the CIN and cervical cancer showed a high diversity in vaginal microbiota. Depletion of Lactobacillus crispatus and increased abundance of anaerobic bacteria were detected in women with cervical disease.

Zhidai Decoction Inhibits Cervical Cancer through Regulation of Vaginal Microbiota

Cervical cancer is one of the top lethal malignancies among women worldwide. The current treatment methods have so many drawbacks that new treatment methods need to be developed. Zhidai Decoction (ZDD) is an effective traditional Chinese herbal formulation for gynecological diseases. Its main effect is controlling abnormal leucorrhea which is a typical early clinical manifestation of cervical cancer. However, how ZDD directly affects cervical cancer has not been addressed. In this study, we established a mouse cervical cancer U14 cell subcutaneous transplantation tumor model and took an early intervention with ZDD to evaluate the antitumor effect of ZDD. In addition, we also investigated the regulatory effects of ZDD on the vaginal microbiota using 16S rRNA analysis in this study. Our results showed that ZDD can significantly improve systemic symptoms and reduce vaginal secretions of tumor-bearing mice. Compared with the CCM group (the cervical cancer model group), in the ZDD-treated group, the tumor inhibitory rate was 37.90%, the average daily food intake of mice was increased to 5.27 ± 0.74 g (P < 0.05), and the survival time was obviously prolonged to 21 days (P < 0.05). Analysis of the sequencing results of 16S rRNA showed that the main microbial genera of the CCM group were Pasteurella (27.20%) and Helicobacter (18.50%), while those in the ZDD group were Staphylococcus (13.22%) and Lactobacillus (4.68%). It revealed that ZDD has the effect of regulating the vaginal microbiota of cervical cancer, especially in increasing the relative abundance of Lactobacillus and Staphylococcus and decreasing the relative abundance of Pasteurella and Helicobacter. The analysis also showed that ZDD could adjust microbiota structure, species abundance, and community compositions of vaginal microbiota. In conclusion, ZDD displayed inhibitory effect on cervical cancer, and it might be based on restoring the balance of vaginal microbiota. Furthermore, our conclusion supports the promotion of ZDD in the early treatment of cervical cancer.

Vaginal microbiota, genital inflammation, and neoplasia impact immune checkpoint protein profiles in the cervicovaginal microenvironment

Emerging evidence suggests that the vaginal microbiota play a role in HPV persistence and cervical neoplasia development and progression. Here we examine a broad range of immune checkpoint proteins in the cervicovaginal microenvironment across cervical carcinogenesis and explore relationships among these key immunoregulatory proteins, the microbiota composition, and genital inflammation. First, we demonstrate that immune checkpoint molecules can be measured in cervicovaginal lavages. Secondly, we identify CD40, CD27, and TIM-3 to specifically discriminate cervical cancer from other groups and CD40, CD28, and TLR2 to positively correlate to genital inflammation. Finally, PD-L1 and LAG-3 levels negatively, whereas TLR2 positively correlate to health-associated Lactobacillus dominance. Overall, our study identifies immune checkpoint signatures associated with cervical neoplasm and illuminates the multifaceted microbiota-host immunity network in the local microenvironment. This study provides a foundation for future mechanistic studies and highlights the utility of cervicovaginal lavage profiling for predicting and monitoring response to cancer therapy.

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.

Cervicovaginal microbiome and natural history of HPV in a longitudinal study

BACKGROUND

Human papillomavirus (HPV) infection is one of the most common sexually transmitted infections. However, only a small percentage of high-risk (HR) HPV infections progress to cervical precancer and cancer. In this study, we investigated the role of the cervicovaginal microbiome (CVM) in the natural history of HR-HPV.

METHODS

This study was nested within the placebo arm of the Costa Rica HPV Vaccine Trial that included women aged 18-25 years of age. Cervical samples from two visits of women with an incident HR-HPV infection (n = 273 women) were used to evaluate the prospective role of the CVM on the natural history of HR-HPV. We focus specifically on infection clearance, persistence, and progression to cervical intraepithelial neoplasia grade 2 and 3 (CIN2+). The CVM was characterized by amplification and sequencing the bacterial 16S V4 rRNA gene region and the fungal ITS1 region using an Illumina MiSeq platform. OTU clustering was performed using QIIME2. Functional groups were imputed using PICRUSt and statistical analyses were performed using R.

RESULTS

At Visit 1 (V1) abundance of Lactobacillus iners was associated with clearance of incident HR-HPV infections (Linear Discriminant Analysis (LDA)>4.0), whereas V1 Gardnerella was the dominant biomarker for HR-HPV progression (LDA>4.0). At visit 2 (V2), increased microbial Shannon diversity was significantly associated with progression to CIN2+ (p = 0.027). Multivariate mediation analysis revealed that the positive association of V1 Gardnerella with CIN2+ progression was due to the increased cervicovaginal diversity at V2 (p = 0.040). A full multivariate model of key components of the CVM showed significant protective effects via V1 genus Lactobacillus, OR = 0.41 (0.22-0.79), V1 fungal diversity, OR = 0.90 (0.82-1.00) and V1 functional Cell Motility pathway, OR = 0.75 (0.62-0.92), whereas V2 bacterial diversity, OR = 1.19 (1.03-1.38) was shown to be predictive of progression to CIN2+.

CONCLUSION

This study demonstrates that features of the cervicovaginal microbiome are associated with HR-HPV progression in a prospective longitudinal cohort. The analyses indicated that the association of Gardnerella and progression to CIN2+ may actually be mediated by subsequent elevation of microbial diversity. Identified features of the microbiome associated with HR-HPV progression may be targets for therapeutic manipulation to prevent CIN2+.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00128661.

Vaginal microbiomes and ovarian cancer: a review

The human microbiome, often termed as "the forgotten organ", is an aggregation of microorganisms and their genomes that forms a mutualistic complex with the host. Recent research has shown the symbiotic merits of a microbiome ecosystem and its crucial role in the hosts' physiological functions. Disruption of this symbiotic relationship is prone to cause a broad spectrum of ailments, including cancer. The compositional and environmental factors that tip the scales from beneficial co-existence to the development of malignancy is actively investigated. Herein we review the latest research in knowledge regarding the association between the vaginal microbiomes and oncogenesis, with a particular focus on ovarian carcinoma.

Cervicovaginal Microbiome and Urine Metabolome Paired Analysis Reveals Niche Partitioning of the Microbiota in Patients with Human Papilloma Virus Infections

In this study, we evaluate the association between vaginal and cervical human papillomavirus infections high-risk types (HPV+H), negative controls (HPV-), the bacterial biota, and urinary metabolites via integration of metagenomics, metabolomics, and bioinformatics analysis. We recently proposed that testing urine as a biofluid could be a non-invasive method for the detection of cervical HPV+H infections by evaluating the association between cervical HPV types and a total of 24 urinary metabolites identified in the samples. As a follow-up study, we expanded the analysis by pairing the urine metabolome data with vaginal and cervical microbiota in selected samples from 19 Puerto Rican women diagnosed with HPV+H infections and HPV- controls, using a novel comprehensive framework, Model-based Integration of Metabolite Observations and Species Abundances 2 (MIMOSA2). This approach enabled us to estimate the functional activities of the cervicovaginal microbiome associated with HPV+H infections. Our results suggest that HPV+H infections could induce changes in physicochemical properties of the genital tract through which niche partitioning may occur. As a result, Lactobacillus sp. enrichment coincided with the depletion of L. iners and Shuttleworthia, which dominate under normal physiological conditions. Changes in the diversity of microbial species in HPV+H groups influence the capacity of new community members to produce or consume metabolites. In particular, the functionalities of four metabolic enzymes were predicted to be associated with the microbiota, including acylphosphatase, prolyl aminopeptidase, prolyl-tRNA synthetase, and threonyl-tRNA synthetase. Such metabolic changes may influence systemic health effects in women at risk of developing cervical cancer. Overall, even assuming the limitation of the power due to the small sample number, our study adds to current knowledge by suggesting how microbial taxonomic and metabolic shifts induced by HPV infections may influence the maintenance of microbial homeostasis and indicate that HPV+H infections may alter the ecological balance of the cervicovaginal microbiota, resulting in higher bacterial diversity.

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.

Oncogenic Virome Benefits from the Different Vaginal Microbiome-Immune Axes

The picture of dynamic interaction between oncogenic viruses and the vaginal bacteria-immune host milieu is incomplete. We evaluated the impact of Polyomaviridae, Papillomaviridae, and Herpesviridae oncoviruses on the vaginal Community State Types (CSTs) and host immune response in reproductive-age women. In our cohort, only Polyomaviridae and Papillomaviridae were detected and were associated with changes in the resident bacteria of CST I and IV (p < 0.05). Lactobacillus crispatus increased in CST I while Prevotella timonensis and Sneathia sanguinegens increased in CST IV. Conversely, CST II and III showed an alteration of the immune response, with the decrease of Eotaxin, MCP-1, IL-7, IL-9, and IL-15 (p < 0.05), leading to reduced antiviral efficacy. An efficient viral clearance was observed only in women from CST I, dominated by Lactobacillus crispatus. Our in vivo study begins to address the knowledge gap with respect to the role of vaginal bacteria and immune response in susceptibility to oncoviral infections.

Patients With LR-HPV Infection Have a Distinct Vaginal Microbiota in Comparison With Healthy Controls

Condyloma acuminatum (CA) is a benign epithelium hyperplasia mainly caused by human papillomavirus (HPV), which is now the second most common viral sexually transmitted infection (STI) in China. In total, 90% of CA patients are caused by the low-risk HPV 6 and 11. Aside from low-risk HPV infection there are likely other factors within the local microenvironment that contribute to CA and there has been related research before. In this study, 62 vaginal specimens were analyzed using 16S rRNA gene sequencing. The diversity of the vaginal microbiota was higher and the composition was different with LR-HPV infection. While the relative abundance of dominant Firmicutes was lower, Actinobacteria, Proteobacteria, and Fusobacteria phyla were significantly higher; at the genus level Gardnerella, Bifidobacterium, Sneathia, Hydrogenophilus, Burkholderia, and Atopobium were higher. This study firstly confirmed a more accurate and comprehensive understanding of the relationship between low-risk HPV infection and vaginal microbiota, in order to provide a theoretical basis for further research on the occurrence and development of CA.

Putative Role of Circulating Human Papillomavirus DNA in the Development of Primary Squamous Cell Carcinoma of the Middle Rectum: A Case Report

Here we present the case of a patient affected by rectal squamous cell carcinoma in which we demonstrated the presence of Human Papillomavirus (HPV) by a variety of techniques. Collectively, the virus was detected not only in the tumor but also in some regional lymph nodes and in non-neoplastic mucosa of the upper tract of large bowel. By contrast, it was not identifiable in its common sites of entry, namely oral and ano-genital region. We also found HPV DNA in the plasma-derived exosome. Next, by in vitro studies, we confirmed the capability of HPV DNA-positive exosomes, isolated from the supernatant of a HPV DNA positive cell line (CaSki), to transfer its DNA to human colon cancer and normal cell lines. In the stroma nearby the tumor mass we were able to demonstrate the presence of virus DNA in the stromal compartment, supporting its potential to be transferred from epithelial cells to the stromal ones. Thus, this case report favors the notion that human papillomavirus DNA can be vehiculated by exosomes in the blood of neoplastic patients and that it can be transferred, at least in vitro, to normal and neoplastic cells. Furthermore, we showed the presence of viral DNA and RNA in pluripotent stem cells of non-tumor tissue, suggesting that after viral integration (as demonstrated by p16 and RNA in situ hybridization positivity), stem cells might have been activated into cancer stem cells inducing neoplastic transformation of normal tissue through the inactivation of p53, p21, and Rb. It is conceivable that the virus has elicited its oncogenic effect in this specific site and not elsewhere, despite its wide anatomical distribution in the patient, for a local condition of immune suppression, as demonstrated by the increase of T-regulatory (CD4/CD25/FOXP3 positive) and T-exhausted (CD8/PD-1positive) lymphocytes and the M2 polarization (high CD163/CD68 ratio) of macrophages in the neoplastic microenvironment. It is noteworthy that our findings depicted a static picture of a long-lasting dynamic process that might evolve in the development of tumors in other anatomical sites.