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

Scoping review protocol on the perception and attitude of women on methods for collecting cervicovaginal samples for human papillomavirus testing in sub-Saharan Africa

INTRODUCTION

Sub-Saharan Africa (SSA) regions have the highest burden of cervical cancer (CC), accounting for nearly a quarter of global mortality. Many women in SSA are reluctant to access CC screening because they are uncomfortable exposing their private parts to healthcare providers. The perception of women who have experienced self-sampling in SSA is yet to be reviewed. This scoping review will explore the literature on the perception and attitude of women towards methods of collecting cervicovaginal samples for human papillomavirus (HPV) testing in SSA.

METHODS AND ANALYSIS

An extensive search using the Arksey and O'Malley framework will be conducted. The search criteria will be limited to original research conducted in community or clinical settings in SSA within the last 10 years. Four databases, namely, PUBMED, Cochrane, African Journals Online and Google Scholar, will be searched. Two independent persons (UIAB and DOO) will screen the titles and abstracts and later full texts using population, intervention, comparison and outcome criteria. IOMB will serve as a tiebreaker whenever there is no agreement on the choice of eligibility criteria. The screening process will be presented using Preferred Reporting Items for Systematic Reviews and Meta-Analyses for the scoping review flow format. The descriptive analysis of eligible studies for scoping reviews will be summarised. We will describe themes of attitude and perception covering pain, embarrassment, privacy and comfortability, willingness to self-sample, anxiety and confidence.

ETHICS AND DISSEMINATION

This is a scoping review protocol and does not require ethical approval. Findings from this review will be disseminated through peer-reviewed publications, the production of policy briefs, and presentations at local and international conferences.

Cervical cancer screening and its associated factors among women of reproductive age in Kenya: further analysis of Kenyan demographic and health survey 2022

INTRODUCTION

Although cervical cancer screening is one of the most effective strategies to reduce the incidence and mortality of cervical cancer, the percentage of cervical cancer screening in low- and middle-income counties is low. In Kenya, the current nationwide prevalence and associated factors for the detection of cervical cancer is unknown. Therefore, this study aimed to assess the prevalence and associated factors for the detection of cervical cancer screening among women of reproductive age in Kenya using the Kenyan Demographic and Health Survey 2022.

METHODS

This study used the most recent Kenyan Demographic and Health Survey data (2022) with a total weighted sample of 16,901 women. A mixed effects logistic regression analysis was performed and in the multivariable analysis, variables with a p-value below 0.05 were considered statistically significant. The strength of the association was evaluated using adjusted odds ratios along with their corresponding 95% confidence intervals.

RESULTS

The prevalence of cervical cancer screening in Kenya was 16.81%(95% CI: 16.24, 17.38%). Having a history of abortion (AOR = 1.33, 95% CI: 1.171.50, 1.43), using modern contraceptive methods (AOR = 1.57, 95% CI: 1.25, 1.95), media exposure (AOR = 1.31, 95%CI: 1.03, 1.65), primary education (AOR = 1.56, 95%CI: 1.09, 2.22), secondary education (AOR = 21.99, 95% CI: 1.1.38, 2.87), higher education (AOR = 2..50, 95% CI: 1.71, 3.65), visiting health facility within the past 12 months (AOR = 1.61, 95%CI: 1.46, 1.79), positive HIV status (AOR: 3.50, 95% CI: 2.69, 4.57), being from a community with a higher proportion of educated individuals (AOR = 1.37, 95%CI: 1.13, 1.65) and being from a community with high proportion of poor individuals (AOR = 0.72, 9 5%CI: 0.60-0.87)) were significantly associated with cervical cancer screening.

CONCLUSION

In Kenya, the prevalence of cervical cancer screening was found to be low. A history of abortion, use of modern contraceptives, exposure to the media, visits to health facilities in the past 12 months, HIV status, level of education, community educational level, and community wealth were identified as significant associated factors for cervical cancer screening. Therefore, it is recommended to implement targeted public health interventions that focus on these identified factors to improve the adoption of cervical cancer screening in Kenya.

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.

HPV co-infections with other pathogens in cancer development: A comprehensive review

High-risk human papillomaviruses (HR-HPVs) cause various malignancies in the anogenital and oropharyngeal regions. About 70% of cervical and oropharyngeal cancers are caused by HPV types 16 and 18. Notably, some viruses including herpes simplex virus, Epstein-Barr virus, and human immunodeficiency virus along with various bacteria often interact with HPV, potentially impacting its replication, persistence, and cancer progression. Thus, HPV infection can be significantly influenced by co-infecting agents that influence infection dynamics and disease progression. Bacterial co-infections (e.g., Chlamydia trachomatis) along with bacterial vaginosis-related species also interact with HPV in genital tract leading to viral persistence and disease outcomes. Co-infections involving HPV and diverse infectious agents have significant implications for disease transmission and clinical progression. This review explores multiple facets of HPV infection encompassing the co-infection dynamics with other pathogens, interaction with the human microbiome, and its role in disease development.

Multidimensional outlook on the pathophysiology of cervical cancer invasion and metastasis

Cervical cancer being one of the primary causes of high mortality rates among women is an area of concern, especially with ineffective treatment strategies. Extensive studies are carried out to understand various aspects of cervical cancer initiation, development and progression; however, invasive cervical squamous cell carcinoma has poor outcomes. Moreover, the advanced stages of cervical cancer may involve lymphatic circulation with a high risk of tumor recurrence at distant metastatic sites. Dysregulation of the cervical microbiome by human papillomavirus (HPV) together with immune response modulation and the occurrence of novel mutations that trigger genomic instability causes malignant transformation at the cervix. In this review, we focus on the major risk factors as well as the functionally altered signaling pathways promoting the transformation of cervical intraepithelial neoplasia into invasive squamous cell carcinoma. We further elucidate genetic and epigenetic variations to highlight the complexity of causal factors of cervical cancer as well as the metastatic potential due to the changes in immune response, epigenetic regulation, DNA repair capacity, and cell cycle progression. Our bioinformatics analysis on metastatic and non-metastatic cervical cancer datasets identified various significantly and differentially expressed genes as well as the downregulation of potential tumor suppressor microRNA miR-28-5p. Thus, a comprehensive understanding of the genomic landscape in invasive and metastatic cervical cancer will help in stratifying the patient groups and designing potential therapeutic strategies.

Cervical Microbiota Influences Cytokine Diversity in Cervical Intraepithelial Neoplasia among Rural Women in the Akyemansa District of Ghana

Background

In recent times, cervical dysbiosis which mostly causes and aggravates infections is highlighted for its role in immune modulation in cervical dysplasia, which promotes the shifting of Th1 phenotype immunity to Th2 phenotype immunity. This study therefore estimated and compared the levels of circulatory IL-4, IL-6, IL-10, TNF-α, and IFN-γ cytokines among adult women identified to have different grades of cervical intraepithelial neoplasia (CIN) and with cervicovaginal infection.

Methods

A total of 157 participants were recruited from the Akyemansa District of Ghana, and cervical swabs and blood samples were taken. The Pap smear test, microbiological culture, and ELISA were employed for cytology analysis, bacteria isolation, and identification and estimation of IL-4, IL-6, IL-10, TNF-α, and IFN-γ cytokines, respectively.

Results

Overall, 14/157 (8.9%) had CIN with 7.6% having CIN 1 and 1.3% having CIN 2. The main predictor for CIN was age above 46 years (OR 11.16, 95% CI: 2.4-51.8). Bacterial vaginosis (p = 0.003) and Candida infection (p = 0.012) were significantly higher in CIN. Again, Staphylococcus aureus (60% vs. 17.6%, p = 0.005), Citrobacter sp. (40.0% vs. 13.2%, p = 0.017), and Morganella morganii (40.0% vs. 4.4%, p = 0.002) isolates were significantly higher in CIN-positive participants. IL-10 and TNF-α concentrations were elevated in participants with CIN 1+ (TNF-α NIL vs. CIN 1+ only, p < 0.05) while IL-6 was decreased among participants with CIN 1+. In the presence of vaginal infection, TNF-α decreased among CIN 1+ participants while IL-10 remained elevated.

Conclusion

The findings of this study suggest that cervical dysbiosis causes immune suppression, which creates a suitable microenvironment for the development of CIN.

Potential role of intratumor bacteria outside the gastrointestinal tract: More than passengers

INTRODUCTION

Tumor-associated bacteria and gut microbiota have gained significant attention in recent years due to their potential role in cancer development and therapeutic response. This review aims to discuss the contributions of intratumor bacteria outside the gastrointestinal tract, in addition to exploring the mechanisms, functions, and implications of these bacteria in cancer therapy.

METHODS

We reviewed current literature on intratumor bacteria and their impact on tumorigenesis, progression, metastasis, drug resistance, and anti-tumor immune modulation. Additionally, we examined techniques used to detect intratumor bacteria, precautions necessary when handling low microbial biomass tumor samples, and the recent progress in bacterial manipulation for tumor treatment.

RESULTS

Research indicates that each type of cancer uniquely interacts with its microbiome, and bacteria can be detected even in non-gastrointestinal tumors with low bacterial abundance. Intracellular bacteria have the potential to regulate tumor cells' biological behavior and contribute to critical aspects of tumor development. Furthermore, bacterial-based anti-tumor therapies have shown promising results in cancer treatment.

CONCLUSIONS

Understanding the complex interactions between intratumor bacteria and tumor cells could lead to the development of more precise cancer treatment strategies. Further research into non-gastrointestinal tumor-associated bacteria is needed to identify new therapeutic approaches and expand our knowledge of the microbiota's role in cancer biology.

Herpes Simplex Virus, Human Papillomavirus, and Cervical Cancer: Overview, Relationship, and Treatment Implications

There is a significant body of research examining the role of human papillomavirus (HPV) in the pathogenesis of cervical cancer, with a particular emphasis on the oncogenic proteins E5, E6, and E7. What is less well explored, however, is the relationship between cervical cancer and herpes simplex virus (HSV). To date, studies examining the role of HSV in cervical cancer pathogenesis have yielded mixed results. While several experiments have determined that HPV/HSV-2 coinfection results in a higher risk of developing cervical cancer, others have questioned the validity of this association. However, clarifying the potential role of HSV in the pathogenesis of cervical cancer may have significant implications for both the prevention and treatment of this disease. Should this relationship be clarified, treating and preventing HSV could open another avenue with which to prevent cervical cancer. The importance of this is highlighted by the fact that, despite the creation of an effective vaccine against HPV, cervical cancer still impacts 604,000 women and is responsible for 342,000 deaths annually. This review provides an overview of HSV and HPV infections and then delves into the possible links between HPV, HSV, and cervical cancer. It concludes with a summary of preventive measures against and recent treatment advances in cervical cancer.

Glycogen availability and pH variation in a medium simulating vaginal fluid influence the growth of vaginal Lactobacillus species and Gardnerella vaginalis

BACKGROUND

Glycogen metabolism by Lactobacillus spp. that dominate the healthy vaginal microbiome contributes to a low vaginal pH (3.5-4.5). During bacterial vaginosis (BV), strict and facultative anaerobes including Gardnerella vaginalis become predominant, leading to an increase in the vaginal pH (> 4.5). BV enhances the risk of obstetrical complications, acquisition of sexually transmitted infections, and cervical cancer. Factors critical for the maintenance of the healthy vaginal microbiome or the transition to the BV microbiome are not well defined. Vaginal pH may affect glycogen metabolism by the vaginal microflora, thus influencing the shift in the vaginal microbiome.

RESULTS

The medium simulating vaginal fluid (MSVF) supported growth of L. jensenii 62G, L. gasseri 63 AM, and L. crispatus JV-V01, and G. vaginalis JCP8151A at specific initial pH conditions for 30 d. L. jensenii at all three starting pH levels (pH 4.0, 4.5, and 5.0), G. vaginalis at pH 4.5 and 5.0, and L. gasseri at pH 5.0 exhibited the long-term stationary phase when grown in MSVF. L. gasseri at pH 4.5 and L. crispatus at pH 5.0 displayed an extended lag phase over 30 d suggesting inefficient glycogen metabolism. Glycogen was essential for the growth of L. jensenii, L. crispatus, and G. vaginalis; only L. gasseri was able to survive in MSVF without glycogen, and only at pH 5.0, where it used glucose. All four species were able to survive for 15 d in MSVF with half the glycogen content but only at specific starting pH levels - pH 4.5 and 5.0 for L. jensenii, L. gasseri, and G. vaginalis and pH 5.0 for L. crispatus.

CONCLUSIONS

These results suggest that variations in the vaginal pH critically influence the colonization of the vaginal tract by lactobacilli and G. vaginalis JCP8151A by affecting their ability to metabolize glycogen. Further, we found that L. jensenii 62G is capable of glycogen metabolism over a broader pH range (4.0-5.0) while L. crispatus JV-V01 glycogen utilization is pH sensitive (only functional at pH 5.0). Finally, our results showed that G. vaginalis JCP8151A can colonize the vaginal tract for an extended period as long as the pH remains at 4.5 or above.

Cervical cancer screening utilization and its predictors among women in bench Sheko Zone, Southwest Ethiopia: using health belief model

BACKGROUND

Cervical cancer is the fourth most frequently diagnosed and found to be the leading cause of cancer death in women, especially in low and middle-income countries. Even though cervical cancer is a preventable disease, its preventive measures have not been equitably implemented across and within different countries; especially in low and middle-income countries, due to different contributing factors.

OBJECTIVE

This study aimed to assess cervical cancer screening utilization and its' predictors among Women in Bench Sheko Zone, Southwest Ethiopia.

METHOD

A community-based cross-sectional study design was employed in Bench Sheko Zone from February 2021 to April 2021. Using a multi-stage stratified sampling method, a total of 690 women in the age range of 30-49 years were included in the study. The logistic regression analysis was used considering a 95% confidence interval and a P-value of < 0.05.

RESULTS

Ninety-six (14.2%) of the participants have utilized cervical cancer screening. Predictors like; age between 40-49 years (AOR = 5.35, 95% CI = [2.89, 9.90]), partner educational status of certificate and above (AOR = 4.36, 95% CI = [1.65, 11.51]), first sexual intercourse before eighteen years (AOR = 4.85, 95% CI = [2.29, 10.26]), ever used of alcohol (AOR = 3.99, 95% CI = [1.23, 12.89]), good knowledge (AOR = 8.98, 95% CI = [4.06, 19.89]), favorable attitude (AOR = 3.56, 95% CI = [1.78, 7.09]), and high perceived benefit (AOR = 2.94, 95% CI = [1.48, 5.84]) were strongly associated with cervical cancer screening utilization.

CONCLUSION

In this study, cervical cancer screening utilization was relatively low. Therefore, promotion of the perception of women towards cervical cancer screening, and provision of health-related information towards different behavioral-related factors should have to be addressed at each level of health care.

Unraveling the Dysbiosis of Vaginal Microbiome to Understand Cervical Cancer Disease Etiology-An Explainable AI Approach

Microbial Dysbiosis is associated with the etiology and pathogenesis of diseases. The studies on the vaginal microbiome in cervical cancer are essential to discern the cause and effect of the condition. The present study characterizes the microbial pathogenesis involved in developing cervical cancer. Relative species abundance assessment identified Firmicutes, Actinobacteria, and Proteobacteria dominating the phylum level. A significant increase in Lactobacillus iners and Prevotella timonensis at the species level revealed its pathogenic influence on cervical cancer progression. The diversity, richness, and dominance analysis divulges a substantial decline in cervical cancer compared to control samples. The β diversity index proves the homogeneity in the subgroups' microbial composition. The association between enriched Lactobacillus iners at the species level, Lactobacillus, Pseudomonas, and Enterococcus genera with cervical cancer is identified by Linear discriminant analysis Effect Size (LEfSe) prediction. The functional enrichment corroborates the microbial disease association with pathogenic infections such as aerobic vaginitis, bacterial vaginosis, and chlamydia. The dataset is trained and validated with repeated k-fold cross-validation technique using a random forest algorithm to determine the discriminative pattern from the samples. SHapley Additive exPlanations (SHAP), a game theoretic approach, is employed to analyze the results predicted by the model. Interestingly, SHAP identified that the increase in Ralstonia has a higher probability of predicting the sample as cervical cancer. New evidential microbiomes identified in the experiment confirm the presence of pathogenic microbiomes in cervical cancer vaginal samples and their mutuality with microbial imbalance.

Screening for cervical cancer among women in five countries in sub-saharan Africa: analysis of the role played by distance to health facility and socio-demographic factors

BACKGROUND

Cervical cancer significantly affects women in Sub-Saharan Africa (SSA). However, limited studies have concentrated on cervical screening behaviour among women in SSA. This study aimed to assess the interplay of distance to health facilities and socio-demographic factors with cervical screening behaviour among women in five SSA countries.

METHODS

The study was based on pooled data of 40,555 women included in Demographic and Health Surveys (DHS) conducted between 2013 to 2021. Proportions and logistic regression models were used in assessing the interplay of distance to health facilities and socio-demographic factors with cervical screening behaviour.

RESULTS

Approximately, 7.9% of women that saw the distance to a health facility as a big problem, tested for cervical cancer compared to 13.5% who indicated that distance to a health facility is not a big problem. More women in urban areas, with a higher level of education, of richest wealth index, aged 40-44 years and using contraceptives who also indicated that distance to a health facility was a big problem tested for cervical cancer compared to those in rural areas with no education, of poorest wealth index, aged 15-19 years and not using contraceptives. Education, age, contraceptive use, frequent exposure to mass media and Sexual Transmitted Infections (STI) had a significant relationship with testing for cervical cancer.

CONCLUSION

The prevalence of cervical cancer screening was low in the five SSA countries largely due to distance barriers and was also significantly influenced by education, age, contraceptive use, frequent exposure to mass media, and STI status. To improve the screening for cervical cancer and its associated benefits in the five SSA countries, there is a need for policymakers, clinicians and public health workers to channel more commitment and efforts to addressing the barriers identified in this study.

Increased diversity of a cervical microbiome associates with cervical cancer

The cervical microbiome (CM) is a complex ecosystem that can change in response to gynecological cancers. We aimed to evaluate changes in the CM of patients who underwent chemoradiation (CRT) therapy for locally advanced cervical cancer. Before and after CRT, cervical swab samples were collected from 16 patients with squamous cell carcinoma of the cervix, and 30 healthy women. All samples were subjected to 16s rRNA-Seq analysis. In healthy premenopausal women the CM comprised mostly Lactobacillus (>90%); the CM community in samples from both pre- and postmenopausal pre-treatment cancer patients was heterogeneous, with a low proportion of Lactobacillus in younger cases. On the genus level, 27 and 11 taxa differentiated healthy controls from cancer patients in pre- and postmenopausal age groups, while 31 and 2 genera differentiated pre- and post-radiation samples and pre-radiation and the follow-up samples, respectively. Microbiome diversity was significantly higher in pre-treatment patients than in healthy controls. The results reveal significant alterations in the CM of cervical cancer patients relative to that in healthy controls; these changes were more striking after CRT. However, further research is needed to determine whether alteration of the CM offers new therapeutic options.

Cervical cancer management in Zimbabwe (2019–2020)

Background

Globally, cervical cancer is the fourth most commonly diagnosed cancer amongst women, and it is especially common in low- and middle-income countries (LMICs). The aim of the study was to determine the current patterns and characteristics of CC management in Zimbabwe in the HIV pandemic era, including the knowledge, attitude and practice of patience.

Methods

The study was a mixed method which incorporated a cross-sectional survey of 408 CC patients which was conducted from October 2019 to September 2020 using an interviewer administered paper questionnaire. The study was conducted at Parirenyatwa hospital, the only cancer treating public health facility in Harare, Zimbabwe. Differences in study outcome by categorical variables were assessed using the Person Chi-square (χ²) test. Odds ratios (unadjusted and adjusted) and 95%CIs for potential risk factors associated with the outcome were estimated using logistic regression model.

Results

From a total of 408 CC patients recruited into the study no prevention mechanism was available or known to these patients and only 13% knew that CC is caused by Human papillomavirus. Only 87 (21%) had ever been screened for CC and 83 (97%) of those who had been screened had the visual inspection with acetic acid procedure done. Prevention (screening uptake) is statistically high among the educated (with secondary education OR = 9.497, 95%CI: 2.349–38.390; with tertiary OR = 59.381, 95%CI: 11.937–295.380). Late presentation varied statistically significantly with marital status (high among the divorced, OR = 2.866; 95% CI: 1.549–5.305 and widowed OR = 1.997; 95% CI: 1.112–3.587), was low among the educated (Tertiary OR = .393; 95% CI: .166-.934), low among those living in the rural (OR = .613; 95% CI: .375-.987), high among those with higher parity OR = 1.294; 95% CI: 1.163–1.439). Less than 1% of the patients had surgery done as a means of treatment. Radiotherapy was administered to 350 (86%) of the patients compared to chemotherapy administered to 155 (38%). A total of 350 (86%) have failed to take medication due to its unavailability, while 344 (85%) missed taking medication due to unaffordability. Complementary and alternative medicines were utilized by 235 (58%). Majority, 278 (68%) were HIV positive, mainly pronounced within age (36–49 years OR = 12.673; 95% CI: 2.110–76.137), among those with higher education (secondary education OR = 4.981; 95%CI: 1.394–17.802 and in those with no co-morbidities (893.956; 95%CI: 129.611–6165.810).

Conclusion

CC management was inadequate from prevention, screening, diagnosis, treatment and palliative care hence there is need to improve CC management in Zimbabwe if morbidity and mortality are to be reduced to acceptable levels. Education helped improve prevention, but reduces chances of diagnosis, working as a doubled edged sword in CC management Prevention was high among the educated. Those in rural areas experience poor CC management. It should be noted that general education is good; however it must be complimented by CC awareness to improve CC management outcomes holistically. Cervical cancer management services need to be decentralized so that those in rural areas have easy access. Given that those with co-morbidities and high parity have better CC management, CC services need to be tied to co-morbidity and antenatal/post-natal care and management services.

Proteases and HPV-Induced Carcinogenesis

Simple Summary

Human papillomavirus (HPV) infection is a sexually transmitted disease with high prevalence worldwide. Although most HPV infections do not lead to cancer, some HPV types are correlated with the majority of cervical cancers, and with some anogenital and oropharyngeal cancers. Moreover, enzymes known as proteases play an essential role in the pathogenic process in HPV-induced carcinogenesis. This review highlights the role of proteases and recent epidemiological data regarding HPV-dependent carcinogenesis.

Abstract

Persistent infection with Human papillomavirus (HPV) is the main etiologic factor for pre-malignant and malignant cervical lesions. Moreover, HPV is also associated with oropharynx and other anogenital carcinomas. Cancer-causing HPV viruses classified as group 1 carcinogens include 12 HPV types, with HPV 16 and 18 being the most prevalent. High-risk HPVs express two oncoproteins, E6 and E7, the products of which are responsible for the inhibition of p53 and pRB proteins, respectively, in human keratinocytes and cellular immortalization. p53 and pRB are pleiotropic proteins that regulate the activity of several signaling pathways and gene expression. Among the important factors that are augmented in HPV-mediated carcinogenesis, proteases not only control processes involved in cellular carcinogenesis but also control the microenvironment. For instance, genetic polymorphisms of matrix metalloproteinase 1 (MMP-1) are associated with carcinoma invasiveness. Similarly, the serine protease inhibitors hepatocyte growth factor activator inhibitor-1 (HAI-1) and -2 (HAI-2) have been identified as prognostic markers for HPV-dependent cervical carcinomas. This review highlights the most crucial mechanisms involved in HPV-dependent carcinogenesis, and includes a section on the proteolytic cascades that are important for the progression of this disease and their impact on patient health, treatment, and survival.

Diagnostic and Therapeutic Uses of the Microbiome in the Field of Oncology

Cancer is a leading cause of death worldwide and it can affect almost every part of the human body. Effective screening and early diagnosis of cancers is extremely difficult due to the multifactorial etiology of the disease and delayed presentation of the patients. The available treatments are usually not specific to the affected organ system, leading to intolerable systemic side effects and early withdrawal from therapies. In vivo and in vitro studies have revealed an association of specific microbiome signatures with individual cancers. The cancer-related human microbiome has also been shown to affect the response of tissues to chemotherapy, immunotherapy, and radiation. This is an excellent opportunity for us to design specific screening markers using the microbiome to prevent cancers and diagnose them early. We can also develop precise treatments that can target cancer-affected specific organ systems and probably use a lesser dose of chemotherapy or radiation for the same effect. This prevents adverse effects and early cessation of treatments. However, we need further studies to exactly clarify and characterize these associations. In this review article, we focus on the association of the microbiome with individual cancers and highlight its future role in cancer screenings, diagnosis, prognosis, and treatments.

Knowledge of Human Papillomavirus and Cervical Cancer among Women Attending Gynecology Clinics in Pretoria, South Africa

Background: Cervical cancer is mainly caused by human papillomavirus (HPV). Worldwide, knowledge of HPV and cervical cancer among women is reported to be inadequate. The study aimed to assess the knowledge and awareness of HPV and cervical cancer among women attending gynecology clinics at a tertiary hospital in Pretoria, South Africa. The study also intended to identify socio-demographic factors influencing women’s knowledge about HPV and cervical cancer risk factors. Methods: This was a clinic-based analytic cross-sectional study conducted among women aged 18 years and older. Participants were enrolled in the clinic waiting rooms while waiting to be attended to by the clinician. A self-administered questionnaire to assess knowledge of HPV, cervical cancer, and risk factors for developing cervical cancer was distributed to the participants. Results: A total of 527 women aged ≥18 years and older were randomly enrolled with a 99.8% response rate. Less than half (47.1%) of the participants had been previously screened for cervical cancer using a Papanicolaou (Pap) test. Few (18.8%) women correctly mentioned cervical cancer risk factors. Unemployed women were less likely to have correct knowledge of cervical cancer causes/risk factors (OR: 0.63; 95% CI 0.40–0.97) compared to employed women. Divorced/separated/widowed women were more likely to have good HPV knowledge compared to single participants (OR: 2.74; 95% CI 1.46–5.15). Conclusion: From this study, it is evident that cervical cancer screening is very low, and women lack knowledge of HPV and cervical cancer disease symptoms and its risk factors. There is a need for policies to prioritize providing accurate information to the public to reduce cervical cancer morbidity and mortality.

Protease activities of vaginal Porphyromonas species disrupt coagulation and extracellular matrix in the cervicovaginal niche

Porphyromonas asaccharolytica and Porphyromonas uenonis are common inhabitants of the vaginal microbiome, but their presence has been linked to adverse health outcomes for women, including bacterial vaginosis and preterm birth. However, little is known about the pathogenesis mechanisms of these bacteria. The related oral opportunistic pathogen, Porphyromonas gingivalis, is comparatively well-studied and known to secrete numerous extracellular matrix-targeting proteases. Among these are the gingipain family of cysteine proteases that drive periodontal disease progression and hematogenic transmission to the placenta. In this study, we demonstrate that vaginal Porphyromonas species secrete broad-acting proteases capable of freely diffusing within the cervicovaginal niche. These proteases degrade collagens that are enriched within the cervix (type I) and chorioamniotic membranes (type IV), as well as fibrinogen, which inhibits clot formation. Bioinformatic queries confirmed the absence of gingipain orthologs and identified five serine, cysteine, and metalloprotease candidates in each species. Inhibition assays revealed that each species’ proteolytic activity can be partially attributed to a secreted metalloprotease with broad substrate specificity that is distantly related to the P. gingivalis endopeptidase PepO. This characterization of virulence activities in vaginal Porphyromonas species highlights their potential to alter the homeostasis of reproductive tissues and harm human pregnancy through clotting disruption, fetal membrane weakening, and premature cervical remodeling.

From Microbiome to Inflammation: The Key Drivers of Cervical Cancer

Cervical cancer is the third leading cause of cancer-related death worldwide. Microbes and hosts form a mutually beneficial symbiosis relationship, and various parts of the host body are microbial habitats. Microbes can trigger inflammation in certain parts of the host body, contributing to cervical cancer development. This article reviews the relationship between cervicovaginal microbes, inflammation and cervical cancer, and discusses the effect of some key cervical microbes on cervical cancer. Finally, probiotic therapy and immunotherapy are summarized.

Molecular Markers to Predict Prognosis and Treatment Response in Uterine Cervical Cancer

Uterine cervical cancer is one of the leading causes of cancer-related mortality in women worldwide. Each year, over half a million new cases are estimated, resulting in more than 300,000 deaths. While less-invasive, fertility-preserving surgical procedures can be offered to women in early stages, treatment for locally advanced disease may include radical hysterectomy, primary chemoradiotherapy (CRT) or a combination of these modalities. Concurrent platinum-based chemoradiotherapy regimens remain the first-line treatments for locally advanced cervical cancer. Despite achievements such as the introduction of angiogenesis inhibitors, and more recently immunotherapies, the overall survival of women with persistent, recurrent or metastatic disease has not been extended significantly in the last decades. Furthermore, a broad spectrum of molecular markers to predict therapy response and survival and to identify patients with high- and low-risk constellations is missing. Implementation of these markers, however, may help to further improve treatment and to develop new targeted therapies. This review aims to provide comprehensive insights into the complex mechanisms of cervical cancer pathogenesis within the context of molecular markers for predicting treatment response and prognosis.

Association of mycoplasma with prostate cancer: A systematic review and meta-analysis

Mycoplasmas are emerging sexually transmitted pathogens usually associated with male urinary tract infection, non-gonococcal urethritis (NGU), infertility, and prostate cancer. In this study, we review the evidence linking mycoplasma infection and prostate cancer. We conducted a systematic review and meta-analysis based on PRISMA guidelines. Four electronic databases were reviewed through January 31, 2021. Studies were eligible for inclusion if odds ratio for prevalence or incidence of colonization and/or infection were provided or calculable. All included studies were evaluated independently by three reviewers. The quality of the included studies was assessed using the Newcastle-Ottawa Scale for Case-Control Studies. Statistical analysis was done using Review Manager Version 5.4. A total of 183/744 (24.6 %) patients with prostate cancer compared to 87/495 (17.58 %) patients with benign prostatic hyperplasia (BPH) tested positive for Mycoplasma spp., while 86/666 (12.91 %) and 11/388 (2.84 %) prostate cancer patients and BPH patients, respectively, had Ureaplasma spp. infections. This meta-analysis showed that prostate cancer patients had 2.24 times higher odds (p = 0.0005) of being colonized with any species of Mycoplasma spp. and 3.6 times increased odds (p = 0.008) of being colonized with any species of Ureaplasma spp. In conclusion, patients with prostate cancer were more likely to be colonized with Mycoplasma spp. or Ureaplasma spp. compared to patients with BPH, which highlights the potential association between chronic infection and cancer. However, more studies are needed to determine the specific role that mycoplasma plays in the pathogenesis of prostate cancer.

Prevalence of high-risk HPV genotypes in sub-Saharan Africa according to HIV status: a 20-year systematic review

OBJECTIVES

This review assessed the rate of high-risk human papillomavirus (HPV) infection among women living in sub-Saharan Africa. It also determined the prevalence of high-risk HPV (hrHPV) among human immunodeficiency virus (HIV) seropositive (HIV+) and seronegative (HIV-) women in sub-Saharan Africa, pre-2010 and post-2010.

METHODS

In this systematic review, Google Scholar, PubMed Central, and Embase were searched to identify cohort and case-control studies that investigated the relationship between HIV and HPV infection. The database searches yielded 17 studies published between 1999 and 2018.

RESULTS

In the general population, the prevalence of any HPV/multiple HPV infections was higher among HIV+ (53.6/22.6%) than among HIV- women (26.5/7.3%) with odds ratios of 3.22 and 3.71, respectively (95% confidence interval, 3.00 to 3.42 and 2.39 to 5.75, p<0.001). The prevalent HPV genotypes among HIV+ and HIV- women diagnosed with invasive cervical cancer (ICC) were HPV-16/18 and HPV-45. The prevalence of HPV-16, HPV-18, and HPV-45 was lower in 1999-2010 (3.8, 1.7, and 0.8%, respectively) than in 2011-2018 (19.1, 6.0, and 3.6%, respectively). Among women diagnosed with ICC, HIV+ women had a higher prevalence of HPV-56, HPV-31, and HPV-51 (7.3, 5.3, and 3.3%, respectively) than HIV- women (1.3, 2.2, and 0.4%, p<0.001, p=0.050, and p=0.013, respectively).

CONCLUSIONS

The prevalence of HPV infection, multiple HPV infections, and non-vaccine HPV types were higher among HIV+ women than among HIV- women in sub-Saharan Africa. Although HIV infection influences the distribution of HPV types, this study suggests that cervical cancer incidence in sub-Saharan Africa is primarily driven by the prevalence of vaccine hrHPVs, especially HPV-16 and HPV-18.

Tumor microbial diversity and compositional differences among women in Botswana with high-grade cervical dysplasia and cervical cancer

INTRODUCTION

We characterized the cervical 16S rDNA microbiome of patients in Botswana with high-grade cervical dysplasia and locally advanced cervical cancer.

METHODS

This prospective study included 31 patients: 21 with dysplasia and 10 with cancer. The Shannon diversity index was used to evaluate alpha (intra-sample) diversity, while the UniFrac (weighted and unweighted) and Bray-Curtis distances were employed to evaluate beta (inter-sample) diversity. The relative abundance of microbial taxa was compared among samples using linear discriminant analysis effect size.

RESULTS

Alpha diversity was significantly higher in patients with cervical cancer than in patients with cervical dysplasia (P<0.05). Beta diversity also differed significantly (weighted UniFrac Bray-Curtis, P<0.01). Neither alpha diversity (P=0.8) nor beta diversity (P=0.19) varied by HIV status. The results of linear discriminant analysis effect size demonstrated that multiple taxa differed significantly between patients with cervical dysplasia vs cancer. Lachnospira bacteria (in the Clostridia class) were particularly enriched among cervical dysplasia patients, while Proteobacteria (members of the Firmicutes phyla and the Comamonadaceae family) were enriched in patients with cervical cancer.

DISCUSSION

The results of our study suggest that differences exist in the diversity and composition of the cervical microbiota between patients with cervical dysplasia and patients with cervical cancer in Botswana. Additional studies are warranted to validate these findings and elucidate their clinical significance among women living in sub-Saharan Africa, as well as other regions of the world.