Frequency and clinical significance of human beta-herpesviruses in cervical samples from Italian women

Association between human herpesvirus infection and cervical carcinoma: a systematic review and meta-analysis

BACKGROUND

Cervical cancer (CC) is one of the most common gynecologic tumors among women around the world. Although the etiological role of human papillomavirus (HPV) in CC is well established, other factors in CC carcinogenesis remains unclear. Here, we performed a systematic review and meta-analysis to explore the association between infections of human herpesvirus (HHVs) and CC risk.

METHODS

Embase and PubMed databases were utilized to search the relevant studies. The revised JBI Critical Appraisal Tool was used to assess the quality of the included studies. Prevalence and odds ratios (ORs) with 95% confidence intervals (CI) were calculated to evaluate the association between viral infection and CC or precancerous cervical lesions (PCL).

RESULTS

Totally 67 eligible studies involving 7 different HHVs were included in meta-analysis. We found an increased risk of CC or PCL that was associated with the overall infection of HHVs (CC, OR = 2.74, 95% CI 2.13-3.53; PCL, OR = 1.95, 95% CI 1.58-2.41). Subgroup analysis showed a trend towards positive correlations between herpes simplex virus type 2 (HSV-2) infection and CC (OR = 3.01, 95% CI 2.24 to 4.04) or PCL (OR = 2.14, 95% CI 1.55 to 2.96), and the same is true between Epstein-Barr virus (EBV) infection and CC (OR = 4.89, 95% CI 2.18 to 10.96) or PCL (OR = 3.55, 95% CI 2.52 to 5.00). However, for HSV-1 and cytomegalovirus (HCMV), there was no association between viral infection and CC or PCL. By contrast, the roles of HHV-6, HHV-7, and Kaposi sarcoma-associated herpesvirus (KSHV) in cervical lesions were unclear due to the limited number of studies.

CONCLUSIONS

This study provided evidence that HHVs infection as a whole increase the risk of CC incidence. In addition, some types of HHVs such as EBV and HSV-2 may serve as potential targets in the development of new interventions or therapeutic strategies for cervical lesions.

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.

Survival‑related DLEU1 is associated with HPV infection status and serves as a biomarker in HPV‑infected cervical cancer

Human papillomavirus (HPV) is the most common risk factor for the occurrence of cervical cancer (CC). In recent years, the important roles of long non‑coding RNAs (lncRNAs) in CC have emerged, but studies on the relationship between lncRNAs and HPV‑positive (HPV+) CC remain scarce. The present study aimed to investigate whether lncRNA deleted in lymphocytic leukemia 1 (DLEU1) is associated with HPV infection and explore the clinical significance of DLEU1 in HPV+ patients with CC. DLEU1 expression was detected by reverse transcription‑quantitative PCR. The ability of DLEU1 to screen patients with CC from controls and differentiate individuals with different HPV infection status was evaluated by receiver operating characteristic analysis. The association of DLEU1 with the survival prognosis of patients with CC was assessed by Kaplan‑Meier survival analysis and Cox regression analysis. The RNA Interactome Database was used to predict molecules interacting with DLEU1. The results indicated that DLEU1 expression was significantly upregulated in CC tissues and cell lines, particularly in those that were HPV+. In addition, DLEU1 had a high diagnostic value in discriminating patients with CC and differentiating between HPV+ and HPV‑ patients with CC, and had a certain ability to screen HPV+ controls. DLEU1 was correlated with HPV infection in CC patients. Furthermore, DLEU1 was indicated to be associated with survival prognosis in both total patients with CC and HPV+ patients with CC, and independently predict the prognosis of patients with CC. Most of the molecules interacting with DLEU1 were microRNAs. In conclusion, abnormal DLEU1 expression is associated with HPV infection and may serve as a diagnostic and prognostic biomarker for HPV+ patients with CC.

Low frequency of human cytomegalovirus in cancerous and precancerous cervical samples of Iranian women

Background: HPV-16 has a significant role in cervical cancers; co-infection with human cytomegalovirus (HCMV) as an oncomodulatory pathogen may increase the risk of carcinogenesis. This study aimed to investigate the frequencies of HCMV and HPV-16 in cervical samples. Materials & methods: A total of 102 cancerous and precancerous cervical samples were examined by real-time PCR targeting the HPV-16 E6 gene, and HCMV immediate-early gene. Results: In total, 65 samples (63.7%) were positive for HPV-16. HCMV was found in seven samples (6.9%). Both HPV-16 and HCMV were present in four samples (cervical intraepithelial neoplasia-3 and squamous cell carcinoma groups with two samples each). Conclusion: HCMV can infect cervical tissues at a low frequency, suggesting that HCMV is unlikely to play a role in the cervical carcinogenesis.

Detection of human herpesvirus 6 (HHV-6) and human herpesvirus 7 (HHV-7) DNA in endocervical samples from a positive and negative HPV woman of Córdoba, Argentina

AIMS

The purpose of the present study was to elucidate the presence of human herpesvirus 6A (HHV-6A), HHV-6B and HHV-7 in samples of the uterine cervix through detection of viral DNA. We analysed normal tissues, samples with low-grade squamous intraepithelial lesions (LSILs) and high-grade squamous intraepithelial lesions (HSILs). We correlated the presence of HHV-6 and HHV-7 with the finding of human papillomavirus (HPV) in mucosal samples.

METHODS

Cervical samples were examined and grouped as follows: group 1 (n=29), normal cytology; group 2 (n=61), samples with LSIL; group 3 (n=35), samples with HSIL. Molecular biology examinations were performed in all samples to detect HHV-6, HHV-7 and HPV DNA and to typify HHV-6 species.

RESULTS

Group 1: normal cytology and HPV (-): HHV-6: 6.8% (2/29), HHV-7: 79.3% (23/29); group 2: LSIL and HPV (-): HHV-6: 93.1% (27/29), HHV-7: 96.5% (28/29); LSIL and HPV (+): HHV-6: 0% (0/32), HHV-7: 90.6% (29/32); group 3: HSIL and HPV (-): HHV-6: 20% (2/10), HHV-7: 70% (7/10); HSIL HPV (+): HHV-6: 12% (3/25), HHV-7: 68% (17/25). HHV-6A DNA was not detected in any samples.

CONCLUSIONS

(1) Both HHV-6 and HHV-7 infect the mucosal cells of the cervix with higher prevalence of HHV-7. (2) The higher prevalence of HHV-6 in LSIL HPV (-) samples compared with those with normal cytology indicates that it constitutes a possible risk factor for atypia production. (3) The presence of HHV-7 in all samples questions its role in the production of atypia. (4) The finding of HHV-6 and HHV-7 suggests that the cervical mucosa is a possible transmission pathway for these viruses.

Human Herpesvirus 6 and Malignancy: A Review

In order to determine the role of human herpesvirus 6 (HHV-6) in human disease, several confounding factors, including methods of detection, types of controls, and the ubiquitous nature of the virus, must be considered. This is particularly problematic in the case of cancer, in which rates of detection vary greatly among studies. To determine what part, if any, HHV-6 plays in oncogenesis, a review of the literature was performed. There is evidence that HHV-6 is present in certain types of cancer; however, detection of the virus within tumor cells is insufficient for assigning a direct role of HHV-6 in tumorigenesis. Findings supportive of a causal role for a virus in cancer include presence of the virus in a large proportion of cases, presence of the virus in most tumor cells, and virus-induced in-vitro cell transformation. HHV-6, if not directly oncogenic, may act as a contributory factor that indirectly enhances tumor cell growth, in some cases by cooperation with other viruses. Another possibility is that HHV-6 may merely be an opportunistic virus that thrives in the immunodeficient tumor microenvironment. Although many studies have been carried out, it is still premature to definitively implicate HHV-6 in several human cancers. In some instances, evidence suggests that HHV-6 may cooperate with other viruses, including EBV, HPV, and HHV-8, in the development of cancer, and HHV-6 may have a role in such conditions as nodular sclerosis Hodgkin lymphoma, gastrointestinal cancer, glial tumors, and oral cancers. However, further studies will be required to determine the exact contributions of HHV-6 to tumorigenesis.

Cervical Viral Infections among Asymptomatic Bulgarian Women

AIM

Although sexually transmitted viral infections are significant and increasing public health concern, little is known about their prevalence among Bulgarian women. The aim of this study was to investigate cervical viral infections in asymptomatic women.

METHODS

The study group included 52 randomly selected asymptomatic female volunteers from Bulgarian border town Kardzhali. Cervical specimens were tested by real-time PCR for human papillomaviruses (HPV), herpes simplex virus (HSV) types 1 and 2, cytomegalovirus (CMV), Epstein-Barr virus (EBV), and human immunodeficiency virus (HIV).

RESULTS

The investigation demonstrated a high rate (61.5%) of infection with one or more viruses of uterine cervix of participating women considered at low risk. The most prevalent was HPV, found in 32.7% of all women. The genotyping of high-risk (HR) HPV positive specimens showed that HPV16 was the most prevalent HR type. HSV prevalence (30.8%) was almost as high as that of HPV and most women were HSV1 infected. 9.6% and 5.8% of all specimens were positive for EBV and CMV, respectively.

CONCLUSIONS

Our results indicate that women from Kardzhali region, involved in this study, might be at risk for development of genital tract pathology, including cervical cancer, and for transmission of virus infection sexually and perinatally.

Vaginal Cytomegalovirus Shedding Before and After Initiation of Antiretroviral Therapy in Rakai, Uganda

Vaginal shedding of cytomegalovirus (CMV) DNA was determined longitudinally among 96 women coinfected with human immunodeficiency virus (HIV), herpes simplex virus 2, and CMV starting antiretroviral therapy (ART) during a placebo-controlled trial of HSV-2 suppression with acyclovir in Rakai, Uganda. Vaginal CMV was detected in 75 of 96 women (78.0%) and 379 of 1080 individual visits (35.1%). ART status, higher HIV RNA viral load before ART initiation, and younger age were significantly associated with increased frequency of CMV shedding (P < .01). Compared to pre-ART, CMV shedding peaked from month 2 to month 4 after ART initiation, suggesting possible immune reconstitution inflammatory syndrome. Further studies need to determine the clinical significance of asymptomatic CMV shedding.

Characterization of cytomegalovirus and epstein-barr virus infection in cervical lesions in Portugal

Infection by high-risk types of human papillomavirus (HPV) is considered necessary but not sufficient for the development of cervical cancer. Previous studies suggested that cytomegalovirus (CMV) and Epstein-barr virus (EBV) could be co-factors of HPV-associated carcinogenesis. The aim of this study was to characterize the prevalence of CMV and EBV and evaluate its association with the development cervical lesions in Portugal. The prevalence of CMV and EBV infections was determined by real-time PCR in 89 cervical samples from women with different histological lesions, who attended the Portuguese Institute of Oncology of Porto. This study revealed an overall prevalence of 4.5% for CMV and 10.1% for EBV. Age-stratified analysis revealed that CMV infection was present in individuals <30 and >60 years old, while EBV infection was present in all age groups. CMV was detected in 9.5% of low-grade lesions and in 22.2% of in situ/invasive carcinomas, while EBV infection was found in all different types of lesions. In addition, data revealed that CMV infection was associated with an increased risk of in situ/invasive carcinoma development (OR=1.28; P=0.035). The study reveals a low prevalence for both viruses; nevertheless, these results are important for knowledge on the shedding of EBV and CMV in cervical samples.

Associations between human herpesvirus-6, human papillomavirus and cervical cancer

Cervical cancer (CxCa) is the second most common cancer among women globally. Human papillomavirus (HPV) infection is thought to be a necessary, but not sufficient, causal factor in CxCa development. Why some women are able to clear HPV infection with no adverse effects, whereas others develop cancer, remains unclear. HHV-6 has demonstrated transformative abilities and has been shown to be present in the genital tract. However, based on the current evidence, we cannot conclude that HHV-6 is a co-factor in HPV-associated carcinogenesis. Nonetheless, future research is warranted because of several crucial gaps in the literature.

Chlamydia trachomatis infection induces replication of latent HHV-6

Human herpesvirus-6 (HHV-6) exists in latent form either as a nuclear episome or integrated into human chromosomes in more than 90% of healthy individuals without causing clinical symptoms. Immunosuppression and stress conditions can reactivate HHV-6 replication, associated with clinical complications and even death. We have previously shown that co-infection of Chlamydia trachomatis and HHV-6 promotes chlamydial persistence and increases viral uptake in an in vitro cell culture model. Here we investigated C. trachomatis-induced HHV-6 activation in cell lines and fresh blood samples from patients having Chromosomally integrated HHV-6 (CiHHV-6). We observed activation of latent HHV-6 DNA replication in CiHHV-6 cell lines and fresh blood cells without formation of viral particles. Interestingly, we detected HHV-6 DNA in blood as well as cervical swabs from C. trachomatis-infected women. Low virus titers correlated with high C. trachomatis load and vice versa, demonstrating a potentially significant interaction of these pathogens in blood cells and in the cervix of infected patients. Our data suggest a thus far underestimated interference of HHV-6 and C. trachomatis with a likely impact on the disease outcome as consequence of co-infection.

Review of cytomegalovirus shedding in bodily fluids and relevance to congenital cytomegalovirus infection

Congenital cytomegalovirus (CMV) infections are a leading cause of sensorineural hearing loss (SNHL) and neurological impairment. Congenital transmission of CMV can occur with maternal primary infection, reactivation, or reinfection during pregnancy. We reviewed studies of CMV shedding in bodily fluids (defined as CMV detected by culture or CMV DNA detected by polymerase chain reaction). Following diagnosis at birth, children with congenital CMV infection exhibited the highest prevalences of CMV shedding (median = 80%, number of sample population prevalences [N] = 6) and duration of shedding, with a steep decline by age five. Healthy children attending day care shed more frequently (median = 23%, N = 24) than healthy children not attending day care (median = 12%, N = 11). Peak shedding prevalences in children occurred at 1-2 years of age, confirming that young children are the key transmission risk for pregnant women. CMV shedding among children was more prevalent in urine specimens than in oral secretions (median prevalence difference = 11.5%, N = 12). Adults with risk factors such as STD clinic attendance had higher shedding prevalences (median = 22%, N = 20) than adults without risk factors (median = 7%, N = 44). In adults with risk factors, CMV was shed more frequently in urine; in adults without risk factors genital shedding was most common. The prevalence of CMV shedding in nine sample populations of pregnant women increased with advancing gestation. In seven sample populations of children with congenital CMV infection, higher viral load at birth was consistently associated with an elevated risk of SNHL. Higher CMV viral load at birth also consistently correlated with the presence of symptoms of congenital CMV at birth. Published 2011. This article is a US Government work and is in the public domain in the USA.

Shedding of Epstein-Barr virus and cytomegalovirus from the genital tract of women in a periurban community in Andhra Pradesh, India

We found a large number of false-positive readings by visual inspection with acetic acid (VIA) in a study of cervical cancer screening strategies (VIA, human papillomavirus HPV DNA testing, and Pap cytology) in a periurban community in Andhra Pradesh, India. We evaluated whether these false-positive readings might be occurring as a result of infections with Epstein-Barr virus (EBV) or cytomegalovirus (CMV), prevalent latent herpesviruses known to be shed from the female genital tract. While we found that there was no association between VIA results and the presence of EBV or CMV in the cervix, we did find a high prevalence of both viruses: 20% for EBV and 26% for CMV. In multivariate analyses, CMV prevalence was associated with younger age, lack of running water in the home, and visually apparent cervical inflammation. EBV prevalence was associated with older age and a diagnosis of cervical intraepithelial neoplasia grade 1 or greater. The biological and clinical implications of these viruses at the cervix remain to be determined. The strong association between the presence of EBV and cervical disease warrants future exploration to determine whether EBV plays a causal role in disease development or if it is merely a bystander in the process.

Cytomegalovirus (CMV) shedding is highly correlated with markers of immunosuppression in CMV-seropositive women

Cytomegalovirus (CMV) enters latency following primary infection and can subsequently reactivate. Reinfection with a different viral strain can also occur. During these events, CMV is shed in bodily fluids. This study examined correlates of CMV shedding in specimens obtained from the HIV Epidemiology Research Study, a multicenter cohort study of US women with or at high risk for human immunodeficiency virus (HIV) infection. Among the women studied, 91.4 % (911/997) were CMV IgG seropositive. Of these women, 2.7 % (25/911) were CMV IgM seropositive. CMV DNA was detected via real-time PCR more frequently in cervicovaginal lavage (CVL) specimens (55/764, 7.2 %) than in peripheral blood mononuclear cells (PBMCs) (26/897, 2.9 %). CMV viral loads in 1 ml CVL (median 534; mean 2598; range = 40-74, 844) were higher than in 10⁶ PBMCs (median 264; mean 1287; range = 35-13 ,250). CMV DNA in PBMCs was associated with HIV seropositivity [odds ratio (OR) 13.5; 95 % confidence interval (CI) 1.8-100], increasing HIV viral load (P<0.001 for trend), decreasing CD4 cell counts (P<0.001 for trend) and CMV DNA in CVL (OR 26; 95 % CI 10.7-64). CMV DNA in CVL specimens was associated with CMV IgM seropositivity (OR 4.3; 95 % CI 1.5-12.3), HIV seropositivity (OR 7.3; 95 % CI 2.6-20), increasing HIV viral load (P<0.001 for trend) and decreasing CD4 cell counts (P<0.001 for trend). The positive predictive value of CMV IgM seropositivity for CMV DNA shedding in either PBMCs or CVL was 20 %. In summary, CMV shedding in CVL and PBMCs was highly correlated with each other and with markers of immune suppression.

Determinants of VIA (Visual Inspection of the Cervix After Acetic Acid Application) positivity in cervical cancer screening of women in a peri-urban area in Andhra Pradesh, India

OBJECTIVES

Visual inspection of the cervix after acetic acid application (VIA) is widely recommended as the method of choice in cervical cancer screening programs in resource-limited settings because of its simplicity and ability to link with immediate treatment. In testing the effectiveness of VIA, human papillomavirus DNA testing, and Pap cytology in a population-based study in a peri-urban area in Andhra Pradesh, India, we found the sensitivity of VIA for detection of cervical intraepithelial neoplasia grade 2 and worse (CIN2+) to be 26.3%, much lower than the 60% to 90% reported in the literature. We therefore investigated the determinants of VIA positivity in our study population.

METHODS

We evaluated VIA positivity by demographics and reproductive history, results of clinical examination, and results from the other screening methods.

RESULTS

Of the 19 women diagnosed with CIN2+, only 5 were positive by VIA (positive predictive value, 3.1%). In multivariate analysis, VIA positivity (12.74%) was associated with older age, positive Pap smear, visually apparent cervical inflammation, and interobserver variation. Cervical inflammation of unknown cause was present in 21.62% of women. In disease-negative women, cervical inflammation was associated with an increase in VIA positivity from 6.1% to 15.5% (P<0.001). Among the six gynecologists who performed VIA, the positivity rate varied from 4% to 31%.

CONCLUSIONS

The interpretation of VIA is subjective and its performance cannot be readily evaluated against objective standards.

IMPACT

VIA is not a robust screening test and we caution against its use as the primary screening test in resource-limited regions.