Cervicovaginal coinfections with human papillomavirus and Chlamydia trachomatis

Deciphering the Puzzle: Literature Insights on Chlamydia trachomatis-Mediated Tumorigenesis, Paving the Way for Future Research

Some infectious agents have the potential to cause specific modifications in the cellular microenvironment that could be propitious to the carcinogenesis process. Currently, there are specific viruses and bacteria, such as human papillomavirus (HPV) and Helicobacter pylori, that are well established as risk factors for neoplasia. Chlamydia trachomatis (CT) infections are one of the most common bacterial sexually transmitted infections worldwide, and recent European data confirmed a continuous rise across Europe. The infection is often asymptomatic in both sexes, requiring a screening program for early detection. Notwithstanding, not all countries in Europe have it. Chlamydia trachomatis can cause chronic and persistent infections, resulting in inflammation, and there are plausible biological mechanisms that link the genital infection with tumorigenesis. Herein, we aimed to understand the epidemiological and biological plausibility of CT genital infections causing endometrial, ovarian, and cervical tumors. Also, we covered some of the best suitable in vitro techniques that could be used to study this potential association. In addition, we defend the point of view of a personalized medicine strategy to treat those patients through the discovery of some biomarkers that could allow it. This review supports the need for the development of further fundamental studies in this area, in order to investigate and establish the role of chlamydial genital infections in oncogenesis.

When Bacteria and Viruses Collide: A Tale of Chlamydia trachomatis and Sexually Transmitted Viruses

The global incidence of sexually transmitted infections (STIs) remains high, with the World Health Organization (WHO) estimating that over 1 million people acquire STIs daily. STIs can lead to infertility, pregnancy complications, and cancers. Co-infections with multiple pathogens are prevalent among individuals with an STI and can lead to heightened infectivity and more severe clinical manifestations. Chlamydia trachomatis (CT) is the most reported bacterial STI worldwide in both men and women, and several studies have demonstrated co-infection of CT with viral and other bacterial STIs. CT is a gram-negative bacterium with a unique biphasic developmental cycle including infectious extracellular elementary bodies (EBs) and metabolically active intracellular reticulate bodies (RBs). The intracellular form of this organism, RBs, has evolved mechanisms to persist for long periods within host epithelial cells in a viable but non-cultivable state. The co-infections of CT with the most frequently reported sexually transmitted viruses: human immunodeficiency virus (HIV), human papillomavirus (HPV), and herpes simplex virus (HSV) have been investigated through in vitro and in vivo studies. These research studies have made significant strides in unraveling the intricate interactions between CT, these viral STIs, and their eukaryotic host. In this review, we present an overview of the epidemiology of these co-infections, while specifically delineating the underlying mechanisms by which CT influences the transmission and infection dynamics of HIV and HSV. Furthermore, we explore the intricate relationship between CT and HPV infection, with a particular emphasis on the heightened risk of cervical cancer. By consolidating the current body of knowledge, we provide valuable insights into the complex dynamics and implications of co-infection involving CT and sexually transmitted viruses.

A literature review on correlation between HPV coinfection with C. trachomatis in cervical neoplasia - coinfection mediated cellular transformation

Cervical cancer is the fourth most common cause of mortality worldwide. Persistent infection with high-risk human papillomaviruses (hrHPV) is a known significant risk factor in cervical neoplasia development (CN). Though HPV contributes to carcinogenesis, other factors fabricate an ideal niche for HPV persistent especially, coinfection with Chlamydia trachomatis (CT) which has been linked to CN development. CT infection is associated with inflammation, cell proliferation, EMT transition and anti-apoptotic processes. To better understand the correlation between HPV-CT coinfection in CN development, a literature review was conducted on the prevalence of HPV-CT coinfection focusing on the role of infection-induced inflammation as HPV-CT coinfection creates an environment for cellular transformation, activates an innate immune response and triggers EMT transition. Moreover, inflammation plays a crucial role in developing neoplasia as there is a decrease in effector cells and a change in the expression of players like ROS and miRs. The CT infection induces chronic inflammation followed by cervical epithelial cell damage and increases susceptibility to HPV infection which may lead to cellular transformation. The literature search was performed based on a comprehensive investigation of publications in the PubMed journal database and Scopus development of CN. We have reviewed the prevalence of HPV-CT infection and the factors increasing the risk of developing CN.

Roles of peptidyl-prolyl isomerase Pin1 in disease pathogenesis

Pin1 belongs to the peptidyl-prolyl cis-trans isomerases (PPIases) superfamily and catalyzes the cis-trans conversion of proline in target substrates to modulate diverse cellular functions including cell cycle progression, cell motility, and apoptosis. Dysregulation of Pin1 has wide-ranging influences on the fate of cells; therefore, it is closely related to the occurrence and development of various diseases. This review summarizes the current knowledge of Pin1 in disease pathogenesis.

Detection of urinary Chlamydia trachomatis, Mycoplasma genitalium and human papilloma virus in the first trimester of pregnancy by PCR method

BACKGROUND

Miscarriage and preterm delivery are the most important challenges of pregnancy. Different bacterial and viral infection may cause miscarriage and preterm delivery. Among bacterial factors, Mycoplasma genitalium and Chlamydia trachomatis have the most important role and human papilloma virus (HPV) is the leading viral factor in this regard.

METHODS

First void urine samples were collected from 119 pregnant women who visited health centers for routine first-trimester screening (12-14 weeks gestation). About 10 ml of the sample was centrifuged at 3000×g for 20 min and 1-2 ml of the sediment was transferred to sterile microfuges and stored at - 20 °C until analysis. DNA extraction was conducted using A101211 kits imported by Pars Tous Biotechnology Company. The following commercial kits, imported by Pars Tous Biotechnology, were used for PCR.

RESULTS

There is no significant association between urinary isolation of C. trachomatis and miscarriage (P = 0.93) and there is no significant association between urinary isolation of M. genitalium and miscarriage (P = 0.80). Regarding HPV, since all urine samples were PCR-negative, comparison was not possible. C. trachomatis was isolated from the urine samples of 6.72% of the pregnant women who underwent first-trimester screening in health centers using PCR. Previous studies reported a mean chlamydia isolation rate of 3% from urine specimens collected from pregnant women in general. T test showed no significant difference between the two groups (P = 0.10). Based on present study the mycoplasma isolation rate was 17.65% using PCR. Previous studies reported a mean mycoplasma isolation rate of 10% from urine specimens collected from pregnant women in general. T-test showed a significant difference between the two groups (P = 0.03).

DISCUSSION

First void urine samples in pregnant women may be an appropriate sample for detection of C. trachomatis and M. genitalium; however, it is not a good method for HPV isolation therefore vaginal or cervical discharge specimens should be used instead for detection of HPV.

Cervical Cancer Induction Enhancement Potential of Chlamydia Trachomatis: A Systematic Review

Human papillomavirus (HPV) persistent infection is the necessary but not sufficient cause of cervical cancer. Other co-factors are required to induce cell transformation that will evolve to malignant cervical cancer. These co-factors include physical elements, other sexually transmitted infections, and immune response. Chlamydia trachomatis the most common bacterial sexually transmitted infection is often asymptomatic but causes various syndromes such as cervicitis, endometritis, pelvic inflammatory disease, and infertility. It is established that this bacterium is involved in cell proliferation process and inhibit apoptosis. Furthermore, C. trachomatis may induce chronic inflammation, interfere with immune response by decreasing the number of antigen presenting cells, and reduce the cell-mediated immunity allowing the persistence of HPV. However, it is unclear whether this bacterium plays a particular role in cervical cancer induction. We therefore aimed at enlightening the actual knowledge about the relationship between C. trachomatis and cervical cancer or precursor lesions through a systematic literature review. We summarized and analyzed the epidemiological data on C. trachomatis and its co-infection with HPV and their association to cervical cancer.

Chlamydia trachomatis infection and HPV/Chlamydia trachomatis co-infection among HPV-vaccinated young women at the beginning of their sexual activity

PURPOSE

This study investigated the prevalence of Chlamydia trachomatis infection, co-infection with Human Papillomavirus (HPV) and associated risk factors in a cohort of sexually active young women enrolled in an ongoing trial on HPV vaccination at the European Institute of Oncology (IEO, Milan, Italy).

METHODS

Cervical samples were collected from 591 girls (median age 18.8 years) at the beginning of their sexual activity. At the time of sample collection, 354 women had not yet been vaccinated, and 237 women had been vaccinated for at least 12 months. All samples were analyzed through a molecular assay for the detection of C. trachomatis infection. Demographic, behavioral risk factors and high-risk HPV (HR-HPV) status were investigated.

RESULTS

The prevalence of C. trachomatis infection was 4.9 % and HPV/C. trachomatis co-infection rate was 1.5 %. The exact analysis has not underlined statistical significance for the variables considered, except for the infection with HR-HPV (p < 0.001). The prevalence of C. trachomatis infection among women who had not been immunized and those already vaccinated was similar (5.6 vs 3.8 %). However, the rate of HPV/C. trachomatis co-infection was twice as high in unvaccinated women (2 %) compared to vaccinated women (0.8 %).

CONCLUSIONS

Over 16 % of young women had at least one of the two STIs investigated. The risk of C. trachomatis infection was higher in HR-HPV infected compared to HR-HPV uninfected young women. The rate of co-infection was halved in HPV-vaccinated compared to unvaccinated women. This study underlines that HPV vaccination can confer benefits also in terms of co-infections prevention, leading to a decreased risk of developing cervical malignancies.

Association of Genital Infections Other Than Human Papillomavirus with Pre-Invasive and Invasive Cervical Neoplasia

Human papillomavirus (HPV) is a well-established causative agent of malignancy of the female genital tract and a common Sexually Transmitted Infection. The probable co-factors that prevent spontaneous clearance of HPV and progression to neoplasia are genital tract infections from organisms like Chlamydia, Trichomonas vaginalis etc, smoking, nutritional deficiencies and multiparity. Inflammatory conditions can lead to pre-neoplastic manifestations in the cervical epithelium; however their specific role in cervical carcinogenesis is not yet established. Therefore it is imperative to study the likely association between HPV and co-infection with various common pathogens in the genital tract of women having cervical precancer or cancer. A "Pubmed" search was made for articles in Literature on this topic using the words: Cervical neoplasia, HPV, co-infections, Cervical Intraepithelial Neoplasia (CIN), Trichomonas vaginalis, Candida, Chlamydia and the relevant information obtained was used to draft the review.

HPV16 E2 enhances the expression of NF-κB and STAT3 target genes and potentiates NF-κB activation by inflammatory mediators

HPV-transformed cells exhibit activation of NF-κB and STAT3 (mediators of inflammation), but very little is known about their regulation under inflammatory conditions before HPV integration. This study reports that cervical tissues with stromal inflammation and intact HPV16 E2 gene show increased expression of target genes of NF-κB and/or STAT3 which can regulate cell survival (cyclin D1, c-Myc, survivin and Bcl2) and inflammatory responses (TNF-α, IL-1β, IL-6, IL-8 and CCR2). Increased expression of RelA, p-IκBα, STAT3, p-STAT3 (Ser727), Pin1 (peptidyl-prolyl cis/trans isomerase) and MCM2 in the squamous epithelia of cervices with stromal inflammation supports early activation of NF-κB-STAT3. Furthermore, HPV16 E2 potentiated NF-κB activation induced by inflammatory mediators, IL-1β and SDF-1α, in HEK293 cells. These results reveal a novel role for E2 in regulating the activities of NF-κB and STAT3 that may have implications in carcinogenic progression of HPV16-infected cells under conditions of stromal inflammation.

[Expression of gamma interferon during HPV and Chlamydia trachomatis infection in cervical samples]

INTRODUCTION

The aim of this study was to mesure the expression of gamma interferon in HPV and Chlamydia trachomatis infection in squamous intraepithelial lesions.

METHOD

Samples from 100 patients diagnosed by colposcopy with or without squamous intraepithelial lesions were used in the present study. Each patient was found to be infected by HPV and C.trachomatis. Relative gamma interferon mRNA expression was assessed using a real-time reverse transcriptase PCR assay (RT-PCR).

RESULTS

The relative units of expression of gamma interferon mRNA were 13, 1.8 and 0.3, for HPV and C.trachomatis co-infection, or HPV or C.trachomatis infection, respectively.

CONCLUSION

HPV and C.trachomatis could overstimulate the expression of gamma interferon.

Chlamydia trachomatis prevalence and chlamydial/HPV co-infection among HPV-unvaccinated young Italian females with normal cytology

Infections caused by Chlamydia trachomatis (Ct) and human papillomavirus (HPV) are the two main sexually transmitted infections; however, epidemiological data on Ct prevalence and Ct/HPV co-infection in Italy are scant. This study aimed at estimating the prevalence of Ct infection and Ct/HPV co-infection in young HPV-unvaccinated females with normal cytology, and placed particular attention on the possible association between Ct-DNA positivity and different HPV infecting genotypes. Five hundred 66 healthy females aged 16-26 years without cervical lesions, previously assessed for HPV infection (HPV-DNA prevalence: 18.2%), were tested for Ct-DNA. The overall prevalence of Ct was 5.8% (95% CI: 4.2-8.1), while Ct/HPV co-infection was recorded in 2.7% (95% CI: 1.6-4.3) of subjects. Compared with HPV-DNA-negative females, HPV-DNA positive subjects had significantly (P < 0.001) higher odds of being infected with Ct (odds ratio of 4.20, 95% CI: 2.01-8.71). Both Ct and Ct/HPV infections were much more prevalent in under 18-year-olds than in older women. Subjects positive for single high-risk HPV genotypes and various multiple HPV infections had higher odds of being Ct-DNA positive. Our findings confirm that HPV and Ct infections are very common among asymptomatic young Italian females. This underlines the urgent need for nationwide Ct screening programs and reinforcement of sexual health education, which would be the most important public health strategies, since no Ct vaccines are currently available.

Chlamydia trachomatis infection and human papillomavirus in women with cervical neoplasia in Pernambuco-Brazil

Chlamydia trachomatis (CT) is the most common bacterial cause of sexually transmitted disease. High-risk human papillomavirus (HR-HPV) is considered the main etiological agent for cervical neoplasia. Evidences showed that the presence of co-infection of CT and HR-HPV plays a central role in the etiology of cervical intraepithelial neoplasia (CIN) and cervical cancer. The goals of this study were: evaluate the human papillomavirus (HPV) and CT prevalence among Brazilian women with abnormal cytology and provide the effect of this association on the severity of cervical neoplasia. The population of this study was composed by 142 women with incident histological incidence of CIN grades I, II, III or cervical cancer from Recife, Northeast of Brazil. The polymerase chain reaction method on a cervical brush specimen was used to detect both agents and the automatic sequencing method was used for HPV genotyping assay. The prevalence of HPV and CT was 100 and 24.65 %, respectively. Thirteen types of HPV were detected; HPV 16, 18, 31 and 33 were the most common. The most prevalent HPV types were HPV 16 and 18. A significant association between CT positive and HPV 16 infection was found (p < 0.0106; OR = 5.31; 95 % IC 1.59-17.67). In the study population, there was diversity of HPV infections, with high-risk types being the most common. Also, the data collected suggest that CT infection may play an important role in the natural history of HPV infection.

Chlamydia trachomatis infection: implications for HPV status and cervical cancer

Genital Chlamydia trachomatis (CT) infections have been identified as a major health problem concern. CT is associated with adverse effect on women reproduction and also associated with cervical hypertrophy and induction of squamous metaplasia, providing a possible relationship with human papillomavirus (HPV) infection. Infection by high-risk HPV types is crucial to the pathogenesis of invasive cervical cancer (ICC), but other co-variants/cofactors must be present for the development of malignancy. CT biological effect may damage the mucosal barrier, improving HPV infection, or may interfere in immune response and viral clearance supporting the persistence of HPV infection. Moreover, CT-related chronic cervical inflammation, decrease of lower genital tract antigen-presenting cells, inhibition of cell-mediated immunity, and anti-apoptotic capacity may influence the natural history of HPV infection, namely persistence progression or resolution. Although several epidemiological studies have stated a positive association involving CT and HPV-related cervical neoplastic lesions and/or cervical cancer (CC), the specific role of this bacterium in the pathogenesis of cervical neoplasia has not been completely clarified. The present review summarizes several studies on CT role in cervical cancer and suggests future research directions on HPV and CT interaction.

Multiple infections and cancer: implications in epidemiology

Approximately 18% of the global cancer burden has been attributed to infectious agents, with estimates ranging from 7% in developed countries to about 22% in developing countries. Chronic infections caused by the hepatitis B and C viruses, human papilloma viruses (HPV), and Helicobacter pylori (H. pylori) are reported to be responsible for approximately 15% of all human cancers. Interestingly, although many of the infectious agents that have been associated with cancer--such as HPV, Epstein-Barr virus (EBV), and H. pylori--are highly prevalent in the world, most infected individuals do not develop cancer but remain lifelong carriers. Malignancies associated with infectious agents may result from prolonged latency as a result of chronic infections. Pathogenic infections are necessary but are not sufficient for cancer initiation or progression. Cancer initiation may require additional cofactors, including secondary infections. Therefore, in patients with chronic infection with one agent, secondary co-infection with another agent may serve as an important co-factor that may cause cancer initiation and progression. Additionally, opportunistic co-infections could significantly inhibit response to cancer treatment and increase cancer mortality. Co-infections are relatively common in areas with a high prevalence of infectious agents, especially in developing countries. These co-infections can cause an imbalance in the host immune system by affecting persistence of and susceptibility to malignant infections. Several articles have been published that focus on infectious agents and cancer. In this article, we discuss the role of infectious agents in malignancies, highlight the role of multiple/co-infections in cancer etiology, and review implications for cancer epidemiology.

Human papillomavirus types 16 and 18 and the prognosis of patients with stage I cervical cancer

OBJECTIVE

This study sought to evaluate the prevalence of human papillomavirus (HPV) types 16 and 18 in women with clinical stage IB cervical cancer treated by radical hysterectomy with pelvic lymphadenectomy as well as to establish a correlation between HPV type and cancer prognosis.

METHODS

A single-center cohort study was conducted with 86 patients who had undergone radical hysterectomy for stage I cervical cancer. Prognostic factors and the presence of HPV 16 and 18 were analyzed using a polymerase chain reaction assay. A univariate analysis using Kaplan-Meier curves was conducted to estimate survival.

RESULTS

The prevalence of HPV 16 in the study group was 65.3%, and the prevalence of HPV 18 was 33.3%. The prevalence of infection with both viruses was 26.9%. Overall survival at 5 years was 91% among women with HPV 18 and 96% among those without this virus type (p=0.133). Among the women with HPV 16, the overall survival was 94%, whereas this rate was 96% among those without this virus type (p=0.663). Disease-free survival was unaffected by the presence of HPV type 16 or 18.

CONCLUSION

In the present study, despite the high prevalence of HPV types 16 and 18, the presence of these virus types did not affect the prognosis of patients with stage I cervical cancer who underwent radical hysterectomy.

Association of HPV infection and Chlamydia trachomatis seropositivity in cases of cervical neoplasia in Midwest Brazil

High-risk human papillomavirus (HPV) is considered the main etiological agent for cervical neoplasia. However, the presence of a single type HPV infection alone is unlikely to be sufficient to cause cervical cancer. There is epidemiologic evidence suggesting that HPV and Chlamydia trachomatis play a central role in the etiology of cervical intraepithelial neoplasia and subsequent cervical cancer. To evaluate the HPV prevalence and the seropositivity for C. trachomatis in women referred to the colposcopy clinic due to an abnormal cervical smear and to examine the effect of this association on the severity of cervical neoplasia. Following enrollment, 131 patients underwent colposcopy and biopsies when necessary. HPV DNA was detected by the polymerase chain reaction (PCR) and genotyping was performed by reverse line-blot hybridization assay. C. trachomatis seropositivity was tested by ELISA for the detection of IgG antibodies. The prevalence of HPV infection was 86.3%. Seropositivity for C. trachomatis was 26%. Thirty-one women (27.4%) were positive for C. trachomatis antibodies and HPV-DNA. The most prevalent HPV type in C. trachomatis-seropositive women were HPV 16 (51.6%) and this HPV type was present mainly in neoplasia cases. Positivity for HPV, particularly HPV types 16 and 18, and C. trachomatis seropositivity was significantly associated with a diagnosis of high grade neoplasia. Borderline significance was observed after adjustment for HPV. C. trachomatis seropositivity is associated with high grade neoplasia in women infected with HPV, mainly when the types 16 and 18 were involved.

Prevalence of Chlamydia trachomatis endocervical infection in systemic lupus erythematosus patients and evaluation of the risk for HPV-induced lesions

Chlamydia trachomatis (CT) is the most common bacterial cause of sexually transmitted disease. It has been associated with arthritis and it is a risk factor for human papillomavirus (HPV)-induced lesions. There are few studies on the frequency of CT infection among systemic lupus erythematosus (SLE) patients. The aim of this study was to determine the prevalence of endocervical CT infection among SLE patients and evaluate whether or not CT infection is a risk factor for HPV-induced lesions. A cross-sectional study included a group of patients who fulfilled the American College Rheumatology criteria for a definite diagnosis of SLE and a control group of non-SLE female individuals from Bahia, Brazil. Polymerase chain reaction was used on endocervical swab specimens to test for CT; a gynecological examination including a cervical cytology and biopsy was done for the identification of HPV lesions. A total of 105 SLE patients were studied, and the control group was composed of 104 age-matched apparently normal women. The prevalence of CT endocervical infection was 3.0 % [confidence interval (CI) 95 % = 0.6-8.0 %] in the SLE group and 5.0 % (95 % CI = 2.0-11.0 %) in the control group; the prevalence ratio was 0.60 (95 % CI = 0.1-2.5). The prevalence of vulvar condyloma was higher among SLE patients (11.0 vs. 1.0 %, p < 0.001), as were the prevalences of low-grade lesion (12.0 vs. 1.0 %, p < 0.001) and cervical intraepithelial neoplasia 1 (9.0 vs. 1.0 %, p = 0.02). There was no association between the presence of HPV lesions and CT infections. However, the small number of patients with CT prevents a definite conclusion from being drawn. The prevalence of endocervical CT infection in women with SLE is low and similar to that of the normal population. This suggests that this infection has no role in the pathogenesis of SLE or the development of HPV-induced lesions.

HPV-DNA integration and carcinogenesis: putative roles for inflammation and oxidative stress

HPV-DNA integration into cellular chromatin is usually a necessary event in the pathogenesis of HPV-related cancer; however, the mechanism of integration has not been clearly defined. Breaks must be created in both the host DNA and in the circular viral episome for integration to occur, and studies have shown that viral integration is indeed increased by the induction of DNA double strand breaks. Inflammation generates reactive oxygen species, which in turn have the potential to create such DNA strand breaks. It is plausible that these breaks enable a greater frequency of HPV-DNA integration, and in this way contribute to carcinogenesis. Consistent with this idea, co-infections with certain sexually transmitted diseases cause cervical inflammation, and have also been identified as cofactors in the progression to cervical cancer. This article examines the idea that inflammation facilitates HPV-DNA integration into cellular chromatin through the generation of reactive oxygen species, thereby contributing to carcinogenesis.

The role of sexual behavior and human papillomavirus persistence in predicting repeated infections with new human papillomavirus types

BACKGROUND

Although human papillomavirus (HPV) infections are common in young women, the rate of and risk for repeated new infections are not well documented. We examined the rate of and risks for new HPV detection in young women.

METHODS

We used data from an ongoing study of HPV, initiated in 1990. Sexually active women ages 12 to 22 years were eligible. Interviews on behaviors and HPV testing were done at 4-month intervals; sexually transmitted infection (STI) testing was annual or if symptomatic. Starting with first HPV detection, time to the next (second) visit (event) with detection of new HPV types, and then the second event to time to third event was calculated. Risks were determined using Cox proportional hazard model.

RESULTS

Sixty-nine percent of 1,125 women had a second event, and of those with a second event, 63% had a third event by 3 years, respectively. Women with HPV persistence from initial visit to second event [hazard ratio (HR) = 4.51 (3.78-5.37)], an STI [HR = 1.47 (1.00-2.17)], bacterial vaginosis [HR = 1.60 (1.07-2.39)], and number of new sex partners [HR = 1.10 (1.05-1.15 per partner/mo)] were independent associations for HPV. Risks for third event were similar.

CONCLUSION

This study documents the repeated nature of HPV infections in young women and their association with sexual risk behaviors.

IMPACT

This finding underscores the lack of clinical utility of HPV testing in young women. Further studies are needed to examine host factors that lead to HPV acquisition and persistence.

The roles of social domains, behavioral risk, health care resources, and chlamydia in spatial clusters of US cervical cancer mortality: not all the clusters are the same

BACKGROUND

While high-risk geographic clusters of cervical cancer mortality have previously been assessed, factors associated with this geographic patterning have not been well studied. Once these factors are identified, etiologic hypotheses and targeted population-based interventions may be developed and lead to a reduction in geographic disparities in cervical cancer mortality.

METHODS

The authors linked multiple data sets at the county level to assess the effects of social domains, behavioral risk factors, local physician and hospital availability, and Chlamydia trachomatis infection on overall spatial clustering and on individual clusters of cervical cancer mortality rates in 2000-2004 among 3,105 US counties in the 48 states and the District of Columbia.

RESULTS

During the study period, a total of 19,898 cervical cancer deaths occurred in women aged 20 and older. The distributions of county-level characteristics indicated wide ranges in social domains measured by demographics and socioeconomic status, local health care resources, and the rate of chlamydial infection. We found that overall geographic clustering of increased cervical cancer mortality was related to the high proportion of black population, low socioeconomic status, low Papanicolaou test rate, low health care coverage, and the high chlamydia rate; however, unique characteristics existed for each individual cluster, and the Appalachian cluster was not related to a high proportion of black population or to chlamydia rates.

DISCUSSION

This study indicates that local social domains, behavioral risk, and health care sources are associated with geographic disparities in cervical cancer mortality rates. The association between the chlamydia rate and the cervical cancer mortality rate may be confounded by other factors known to be a risk for cervical cancer mortality, such as the infection with human papillomavirus. The findings will help cancer researchers examine etiologic hypotheses and develop tailored, cluster-specific interventions to reduce cervical cancer disparities.

Chlamydia trachomatis-infected host cells resist dsRNA-induced apoptosis

Human pathogenic Chlamydia trachomatis have evolved sophisticated mechanisms to manipulate host cell signalling pathways in order to prevent apoptosis. We show here that host cells infected with C. trachomatis resist apoptosis induced by polyI:C, a synthetic double-stranded RNA that mimics viral infections. Infected cells displayed significantly reduced levels of PARP cleavage, caspase-3 activation and a decrease in the TUNEL positive population in the presence of polyI:C. Interestingly, the chlamydial block of apoptosis was upstream of the initiator caspase-8. Processing of caspase-8 was reduced in infected cells and coincided with a decrease in Bid truncation and downstream caspase-9 cleavage. Moreover, the enzymatic activity of caspase-8, measured by a luminescent substrate, was significantly reduced in infected cells. Caspase-8 inhibition by Chlamydia was dependent on cFlip as knock-down of cFlip decreased the chlamydial block of caspase-8 activation and consequently reduced apoptosis inhibition. Our data implicate that chlamydial infection interferes with the host cell's response to viral infections and thereby influences the fate of the cell.

Coinfection of Chlamydia trachomatis, Ureaplasma urealyticum and human papillomavirus among patients attending STD clinics in Estonia

Women visiting Estonian STD clinics were subjected to PCR assay for human papillomavirus (HPV), Chlamydia trachomatis and Ureaplasma urealyticum biovar 2. The overall prevalence of coinfection was 8%. The chlamydial infection was found to be associated with HPV, especially with high-risk HPV (OR=2.5, p<0.005) and most significantly in women over 41 y of age. C. trachomatis infection also occurred more frequently in U. urealyticum-infected than in U. urealyticum-free patients (OR=2.6, p=0.02). U. urealyticum infection did not associate with HPV status. The clinical significance of the association between C. trachomatis and U. urelyticum infection remains to be elucidated.

Immunization with chlamydial plasmid protein pORF5 DNA vaccine induces protective immunity against genital chlamydial infection in mice

To validate the immune protective efficacy of pORF5 DNA vaccine and to analyze potential mechanisms related to this protection. In this study, pORF5 DNA vaccine was constructed and evaluated for its protective immunity in a mouse model of genital chlamydial infection. Groups of BALB/c mice were immunized intranasally with pORF5 DNA vaccine. Humoral and cell mediated immune responses were evaluated. The clearance ability of chlamydial challenge from the genital tract and the chlamydia-induced upper genital tract gross pathology and histopathological characterization were also detected. The results showed that the total and the IgG2a anti-pORF5 antibody levels in serum were significantly elevated after pcDNA3.1-pORF5 vaccination, as were the total antibody and IgA levels in vaginal fluids. pcDNA3.1-pORF5 induced a significantly high level of Th1 response as measured by robust gamma interferon (IFN-gamma). Minimal IL-4 was produced by immune T cells in response to the re-stimulation with pORF5 protein or the inactive elementary body in vitro. pcDNA3.1-pORF5-vaccinated mice displayed significantly reduced bacterial shedding upon a chlamydial challenge and an accelerated resolution of infection. 100% of pcDNA3.1-pORF5 vaccinated mice successfully resolved the infection by day 24. pcDNA3.1-pORF5-immunized mice also exhibited protection against pathological consequences of chlamydial infection. The stimulated index was significantly higher than that of mice immunized with pcDNA3.1 and PBS (P<0.05). Together, these results demonstrated that immunization with pORF5 DNA vaccine is a promising approach for eliciting a protective immunity against a genital chlamydial challenge.

Utilization of human papillomavirus testing for cervical cancer prevention in a university hospital

This study aimed to evaluate the performance and cost of using polymerase chain reaction (PCR) and hybrid capture in the detection of cervical intraepithelial neoplasia (CIN) in patients with cytological abnormalities (ASCUS/low-grade squamous intraepithelial lesion--LSIL), and the feasibility of implementing these methods in Brazil's Unified National Health System (SUS). Colposcopy gave a negative predictive value of 92.86% and efficiency of 87.8% for diagnosing CIN. The sensitivity of PCR and hybrid capture for detecting CIN was 83.33% and 66.67%, respectively, and the negative predictive value for diagnosing CIN2/CIN3 was 100% and 94.74%, respectively. The annual cost for 80 patients was lower when all patients with ASCUS/LSIL were referred for colposcopy than when HPV testing was performed and those with positive results were referred for colposcopy. Therefore, at present, it is financially unfeasible for the National Health System to implement HPV testing to screen patients with cytological abnormalities (ASCUS/LSIL). However, considering that large-scale use might make such methods cheaper, PCR should be the chosen method, since it is less expensive, more sensitive, and has a high negative predictive value.

Etiology and pathogenesis of precancerous lesions and invasive cervical carcinoma

Cervical cancer is the second most common gynecological malignancy in the world. Human papilloma virus (HPV) infection is the leading ethiologic agent in the development of premalignant and malignant cervical diseases. HPV is a member of the Papovaviridae family and until now over 100 types have been recognized. There are two types of viral infection: latent and productive. Virus induced oncogenesis is the result of interaction between virus oncoproteins E6 and E7 and tumor supresor host genes p53 and Rb. Many cofactors such as immunosuppression, early sexual relationship, multiple sexual partners, other sexualy transsmited infections and smooking are contributing factors of the precancerous and invasive cervical lesions. According to the oncogenic potential HPV are divided into three groups: low, intermediate and high oncogenic risk viruses. Molecular technics which are used for the virus detection are: In situ hibridisation,, Hybrid capture test and polymerasa chain reaction. Human papilloma virus testing has an important role in the follow up and treatment of women with 'atypical squamous cells of unknown significant' changes in cervical smears and low-grade squamous intraepithelial lesions, changes in punch biopsy.

Urine versus brushed samples in human papillomavirus screening: study in both genders

AIM

To investigate whether urine is a good medium for screening and whether there is a correlation between the amount of extracted DNA and human papillomavirus (HPV)-positivity.

METHODS

In the present study, 30 first-voided urine (FVU) specimens and 20 urethroglandular swabs using cervex-brushes from male partners of HPV-positive patients, and 31 FVU specimens and 100 liquid-based cervix cytology leftovers sampled with cervix-brushes from HPV-positive women were examined for the presence of beta-globin. Oncogenic HPV were detected using type-specific PCR.

RESULTS

beta-globin was found in all the brushed samples, whereas it was found in only 68.9% of the FVU specimens. HPV-PCR was positive in 60.0% of the male brushes, in 29% of the female brushes and in 0% of the male FVU specimens. DNA concentration was, respectively, 0.9998 ng/microL, 37.0598 ng/microL and 0.0207 ng/microL.

CONCLUSION

Urine is not a good tool for HPV detection, probably because the low DNA concentration reflects a low amount of collected cells. beta-globin is measurable in FVU by real time quantitative PCR, but the DNA concentration is lower compared to brush sampling for both genders. beta-globin-positivity of urethral and cervical swabs is 100%, showing a higher mean concentration of DNA, leading to a higher detection rate of HPV. This is the first article linking DNA-concentration to the presence of HPV.

The oncogenic potential of human papillomaviruses: a review on the role of host genetics and environmental cofactors

Human papillomaviruses (HPVs), with over 100 genotypes, are a very complex group of human pathogenic viruses. In most cases, HPV infection results in benign epithelial proliferations (verrucae). However, oncogenic types of HPV may induce malignant transformation in the presence of cofactors. For example, over 99% of all cervical cancers and a majority of vulval, vaginal, anal and penile cancers are the result of oncogenic HPV types. Such HPV types have been increasingly linked to other epithelial cancers involving the skin, larynx and oesophagus. Although viral infection is necessary for neoplastic transformation, evidence suggests that host and environmental cofactors are also required. Research investigating HPV oncogenesis is complex and quite extensive. The inability to produce mature HPV virions in animal models has been a major limitation in fully elucidating the oncogenic potential and role of associated cofactors in promoting malignant transformation in HPV-infected cells. We have reviewed the literature and provide a brief account of the current understanding of HPV oncogenesis, emphasizing the role of genetic susceptibility, immune response, and environmental and infectious cofactors.

The importance of chlamydial infections in obstetrics and gynaecology: An update

Chlamydia is now the most common notifiable infectious disease in many countries, a fact that has serious ramifications for the reproductive health of women. This review highlights the epidemiology, pathophysiology, clinical features and reproductive sequelae of the infection. Current screening and management methods are outlined. Obstetricians and gynaecologists are ideally placed to play a major role in the primary prevention of this significant sexually transmitted infection.

Molecular detection ofChlamydia trachomatis and HPV infections in cervical samples with normal and abnormal cytopathological findings

It has been suggested that Chlamydia trachomatis (CT) and human papillomaviruses (HPV) co-infection could contribute to development of intraepithelial lesions. In this study, HPV and CT-DNA were investigated in 250 cervicovaginal samples of patients from Minas Gerais, Brazil. The cytological analysis revealed that 70% of samples (175) were negative, 5.2% (13) presented atypical squamous or glandular cells of undetermined significance (ASCUS/AGUS), 12.4% (31) presented low-grade squamous intraepithelial lesion (LSIL), 10.8% (27) high-grade squamous intraepithelial lesion (HSIL), and 1.6% (4) invasive carcinoma. HPV-DNA and HPV/CT co-infection was observed in 40% (100/250) and in 5.2% (13/250) of samples, respectively. Among the positive cytological samples, HPV-DNA was detected in 73.3% and CT-DNA in 9.33% and in 13%, if only the HPV positive samples were considered. The highest co-infection rate (15.4%) was observed among ASCUS/AGUS samples. Although a significant association was found for HPV infection and the precursor lesions of cervical cancer, it was not possible to establish a significant association between these lesions and CT or HPV/CT co-infection.

Human papillomavirus DNA in urine samples of women with or without cervical cancer and their male partners compared with simultaneously collected cervical/penile smear or biopsy specimens

Infection of specific types of high-risk human papillomaviruses (HPVs) causes cervical cancer in women. Conventional test for genital HPV infection requires collection of scraped cervical cells or biopsy specimens, which involves invasive procedures. Utility of non-invasive urine sampling for detection of HPV in women and their male sexual partners is controversial. The validation of this urine-based HPV DNA test is of immense value not only in screening large population and children but also for HPV vaccine monitoring in adolescents. We examined the frequency of high risk HPV types 16 and 18 in simultaneously collected urine samples and cervical scrapes or biopsy specimens from women with cervical cancer and their single lifetime male sexual partners in order to validate the utility of urine sampling as a reliable non-invasive method for detection of genital HPV infection. Thirty women with invasive cervical cancer and their husbands along with 30 age-matched normal healthy women including their husbands were recruited for the study. Cervical biopsies/scrapes from women subjects and penile scrapes from their husbands and urine samples from all of them were collected before taking biopsy or scrapes. HPV-L1 consensus primer as well as high-risk HPV (HPV 16 and 18) type-specific oligo-primers were used for PCR detection of HPV DNA. The total frequency of HPV in women with cervical cancer was found to be 83% (25/30) while it was only 67% (20/30) in their male partners but there was virtually no difference in results between urine and scrape or tissue biopsy either in women or their male partners. Although healthy women and their husbands showed similar frequency of HPV infection both in urine and scrape samples, there was a significant difference (p=0.05) in the prevalence of high risk HPV type 16 in women with cervical cancer (70%) and their male partners (30%). Similar was the trend between control women and their male partners. The results also showed a very high prevalence of HPV type 16 among Indian women with cervical cancer while its frequency was significantly low in their single lifetime male partners. The case by case matching of HPV positivity and negativity between urine and cervical/penile scrapes or biopsies obtained from women and their male partners demonstrated that the non-invasive urine sampling can be reliably used for screening genital HPV infection in both men and women.

Human papillomavirus (HPV) DNA detection in self-collected urine

OBJECTIVE

Non-invasive sampling of human genitals to identify high-risk individuals with subclinical oncogenic HPV infection remains a challenge. The study was designed to see if self-collected urine can be used as a simple, non-invasive sampling for screening HPV, particularly for screening/monitoring general population or young adolescents or infants, if they are to be immunized by HPV vaccines.

METHOD

Self-collected urine samples from 100 sexually unexposed college going girls and cervical scrapes from 104 normal healthy sexually active married women were used in this study. Additionally, a group of 55 women were recruited for collecting first urine and later scraped cervical cells to validate urine sampling by directly comparing HPV positivity between the two types of biological specimens. A dry 'paper smear' method for specimen collection and a simple single tube protocol was employed for PCR detection of HPV infection.

RESULTS

Out of 100 sexually inexperienced college going girls, only 6 (6%) were positive for HPV infection as revealed by L1 consensus primer and 4 (4%) of them were positive for HPV 16 but none was found positive for HPV 18 DNA. Out of 104 sexually active married women who were cytologically reported as negative by Pap test, 11 (10.5%) were found HPV positive and 7 (6.7%) of them had infection of high-risk HPV type 16. Both urine and later cervical scrapes from a group of 55 women collected as dry 'paper smear' showed perfect matching positivity for HPV between urine and cervical scrape.

CONCLUSIONS

The use of urine coupled with its dry collection as 'paper smear' facilitating their easy transport, storage and direct PCR detection of HPV DNA opens up an alternative non-invasive approach for population screening of HPV infection, at least in such cases as children and infants in whom invasive samples are difficult to obtain.

Chlamydia trachomatis and Human papillomavirus infections in cervical disease in Argentine women

OBJECTIVES

To examine the prevalence of Human papillomavirus and Chlamydia trachomatis DNA in cervical samples among women with normal and abnormal cervical cytology from La Plata, Argentina.

METHODS

Two hundred and seventy-nine women (200 with cervical neoplasia or ICC and 79 women with normal cytology) provided cervical samples for the detection of HPV and C. trachomatis DNA by PCR-based assays.

RESULTS

HPV DNA increased with the cervical lesion severity, ranging from 30% among women with normal cytology to 99-100% among women with HSIL or ICC. C. trachomatis DNA prevalence increased from low levels in women with normal cytology (11%) to 47% in those with HSIL, but was uncommon among ICC patients (20%). Among women with normal cytology, C. trachomatis prevalence was higher in HPV DNA positive (12.5%) than HPV DNA negative women (10.9%), but this difference was not significant.

CONCLUSIONS

HPV prevalence in the general population is slightly higher than those reported for other developing countries. C. trachomatis DNA positivity was associated with a higher risk of both LSIL and HSIL lesions, but not with ICC.

Replication and interaction of herpes simplex virus and human papillomavirus in differentiating host epithelial tissue

We have investigated the interactions and consequences of superinfecting and coreplication of human papillomavirus (HPV) and herpes simplex virus (HSV) in human epithelial organotypic (raft) culture tissues. In HPV-positive tissues, HSV infection and replication induced significant cytopathic effects (CPE), but the tissues were able to recover and maintain a certain degree of tissue integrity and architecture. HPV31b not only maintained the episomal state of its genomic DNA but also maintained its genomic copy number even during times of extensive HSV-induced CPE. E2 transcripts encoded by HPV31b were undetectable even though HPV31b replication was maintained in HSV- infected raft tissues. Expression of HPV31b oncogenes (E6 and E7) was also repressed but to a lesser degree than was E2 expression. The extent of CPE induced by HSV is dependent on the magnitude of HPV replication and gene expression at the time of HSV infection. During active HSV infection, HPV maintains its genomic copy number even though genes required for its replication were repressed. These studies provide new insight into the complex interaction between two common human sexually transmitted viruses in an in vitro system, modeling their natural host tissue in vivo.