Chlamydia trachomatis infection and persistence of human papillomavirus

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.

Patterns of persistent genital human papillomavirus infection among women worldwide: a literature review and meta-analysis

Persistent high-risk human papillomavirus (HR-HPV) infection is the strongest risk factor for high-grade cervical precancer. We performed a systematic review and meta-analysis of HPV persistence patterns worldwide. Medline and ISI Web of Science were searched through January 1, 2010 for articles estimating HPV persistence or duration of detection. Descriptive and meta-regression techniques were used to summarize variability and the influence of study definitions and characteristics on duration and persistence of cervical HPV infections in women. Among 86 studies providing data on over 100,000 women, 73% defined persistence as HPV positivity at a minimum of two time points. Persistence varied notably across studies and was largely mediated by study region and HPV type, with HPV-16, 31, 33 and 52 being most persistent. Weighted median duration of any-HPV detection was 9.8 months. HR-HPV (9.3 months) persisted longer than low-risk HPV (8.4 months), and HPV-16 (12.4 months) persisted longer than HPV-18 (9.8 months). Among populations of HPV-positive women with normal cytology, the median duration of any-HPV detection was 11.5 and HR-HPV detection was 10.9 months. In conclusion, we estimated that approximately half of HPV infections persist past 6 to 12 months. Repeat HPV testing at 12-month intervals could identify women at increased risk of high-grade cervical precancer due to persistent HPV infections.

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.

Clinical trials of human papillomavirus vaccines and beyond

Human papillomavirus (HPV) is the most common sexually transmitted infectious agent; its 14 oncogenic types are causally associated with 5-10% of all cancers. The major structural HPV protein self-assembles into immunogenic virus-like particles. Two licensed HPV vaccines--the bivalent vaccine comprising HPV types 16 and 18, and the quadrivalent vaccine comprising HPV types 6, 11, 16 and 18--have proven to be safe and efficacious against 6-month-persistent cervical infections of HPV16 and HPV18 and associated precancerous lesions, and both have efficacies of 90-100%. Among baseline HPV-negative adolescent females, vaccine efficacies against the immediate precursor of cervical cancer (intraepithelial neoplasia grade 3) irrespective of HPV type are 93.2% and 43.0% for the bivalent and quadrivalent vaccines, respectively. The quadrivalent vaccine is efficacious (>75% vaccine efficacy) against any of the more-severe precursors of vulval, vaginal and anal cancers. A strong increase in vaccine efficacy with increasing severity of the precancerous lesion is explained by accumulation of the most-oncogenic HPV types 16 and 18 in these lesions. Therefore, prophylactic HPV vaccination will exceed the best results from screening for cancer. With the extremely efficacious prophylactic HPV vaccines, the focus of organized intervention (vaccination and screening) programmes should, however, shift from reducing the HPV disease burden to controlling the prevalence of oncogenic HPV (and nononcogenic HPV) types. Eradication of the major oncogenic HPV types should be pursued.

Immunosuppression and risk of cervical cancer

A markedly increased risk of cervical cancer is known in women immunosuppressed due to AIDS or therapy following organ transplantation. The aim of this review is to determine the association between other conditions affecting the immune system and the risk of cervical cancer. Patients with end-stage renal disease seem to be at an increased risk of cervical cancer. A higher risk of cervical precancerous lesions was found in patients with some autoimmune diseases; particularly if treated with immunosuppressants. Among behavioral factors weakening the immune system, smoking appeared to strongly increase the risk of cervical cancer, while poor diet only moderately increased the risk. It is difficult to determine whether sexually transmitted infections other than human papillomavirus infection are independent risk factors. Identifying those groups of women likely to fail in clearing persistent human papillomavirus infections would help individualize screening guidelines and target immune-associated factors in the cervical cancer etiology.

Human papillomavirus: what every provider should know

Persistence of human papillomavirus (HPV) infection is necessary for the development of cervical cancer. Additionally, infection with HPV is implicated in the majority of cases of other genital tract malignancies including vulvar, penile, and vaginal cancer. HPV testing and vaccination are a routine part of obstetrical/gynecological clinical practice. With an enhanced public awareness of HPV infections, many patients turn to their obstetricians/gynecologists with questions about transmission, testing, and prevention. In this review, we will discuss the biology of HPV, epidemiology of disease, methods and indications for testing, and vaccination strategies.

Chlamydia trachomatis as a probable cofactor in human papillomavirus infection in aboriginal women from northeastern Argentina

OBJECTIVES

High-risk types of human papillomavirus (HPV) are strongly associated with cervical cancer (CC), and Chlamydia trachomatis (CT), the most frequent sexually transmitted bacterial infection (STBI) worldwide, seems to be a risk factor for HPV infection and for CC. It is also known that both agents are more prevalent in vulnerable communities where lack of adequate primary health care is a cause for concern. The aim of this work was to determine the impact of CT and HPV infections in women belonging to an isolated aboriginal population (Pilaga community) from a poor region in Northern Argentina (province of Formosa). For this purpose, a cross-sectional study was performed in all sexually active Pilaga women, who attended a local community-based gynecological health screening project. The polymerase chain reaction (PCR) method on a cervical brush specimen was used to detect both agents.

RESULTS

A total of 227 women (20% of the total female population of the Pilaga community) were studied and the overall prevalence was 26.4% for CT, 46.7% for HPV and 16.3% for concurrent infection. CT infection was higher in HPV DNA positive (34.2%) than in HPV DNA negative women (19%; OR: 2.22/95% CI = 1.16-4.28 / p = 0.009) and the most prevalent HPV types were HPV-16 (19.4%), 6 and 18 (5.3%), 58 (3.5%) and 33 (3.1%).

CONCLUSIONS

The prevalence of CT and HPV observed in Pilaga women are among the worst registered in Latin America. Also, data collected suggest that chlamydial infection may play an important role in the natural history of HPV infection. On this respect, we propose that the association between these two agents seems to be more related to a mutual potentiation than to the fact that they share a common route of transmission.

Evaluation of the cobas 4800 CT/NG Test for detecting Chlamydia trachomatis and Neisseria gonorrhoeae DNA in urogenital swabs and urine specimens

We have evaluated 696 samples (488 swabs and 208 urine specimens) with the cobas 4800 (c4800) CT/NG Test for the detection of Chlamydia trachomatis and Neisseria gonorrhoeae DNA in swab and urine specimens. c4800 results were compared with those obtained from COBAS AMPLICOR (CAM) CT/NG Test. Discordant results were reanalyzed with the MultiNA system and compared with clinical data. For C. trachomatis detection by both methods, we obtained 93.8%, 100%, 100%, and 99.1% for sensitivity, specificity, and positive and negative predictive values, respectively. For urine specimens analyzed in c4800, our results were 96.6%, 100%, 100%, and 99.4%, respectively. For N. gonorrhoeae detection, swab results were:88.0%, 100%, 100%, and 99.4%. For urine specimen, results obtained were 100%, 100%, 100%, and 100%. Reanalyses were all concordant between both methods. c4800 results were comparable with those obtained with the CAM system. We had an excellent correlation between swab and urine specimens analyzed by c4800.

Prevalence and risk factors for cervical HPV infection and abnormalities in young adult women at enrolment in the multinational PATRICIA trial

OBJECTIVE

We evaluated baseline data from the PApilloma TRIal against Cancer In young Adults (PATRICIA; NCT00122681) on the association between behavioral risk factors and HPV infection and cervical abnormalities.

METHODS

Women completed behavioral questionnaires at baseline. Prevalence of HPV infection and cervical abnormalities (detected by cytological or histological procedures) and association with behavioral risk factors were analyzed by univariate and stepwise multivariable logistic regressions.

RESULTS

16782 women completed questionnaires. Among 16748 women with data for HPV infection, 4059 (24.2%) were infected with any HPV type. Among 16757 women with data for cytological abnormalities, 1626 (9.7%) had a cytological abnormality, of whom 1170 (72.0%) were infected with at least one oncogenic HPV type including HPV-16 (22.7%) and HPV-18 (9.3%). Multivariable analysis (adjusted for age and region, N=14404) showed a significant association between infection with any HPV type and not living with a partner, smoking, age <15 years at first sexual intercourse, higher number of sexual partners during the past 12 months, longer duration of hormonal contraception and history of sexually transmitted infection (STI). For cervical abnormalities, only history of STI (excluding Chlamydia trachomatis) remained significant in the multivariable analysis after adjusting for HPV infection.

CONCLUSIONS

Women reporting 3+ sexual partners in the past 12 months had the highest risk of HPV infection at baseline. HPV infection was the main risk factor for cervical abnormalities, and history of STIs excluding Chlamydia trachomatis increased risk to a lesser extent. Although behavioral factors can influence risk, all sexually active women are susceptible to HPV infection.

Bacterial isolates from the urine of cattle affected by urothelial tumors of the urinary bladder

Microbiological investigations were performed on urine samples from 108 cows affected by urothelial tumors of the urinary bladder. Bacteria, frequently of mixed population, were isolated from 100 animals. Gram-positive bacteria prevailed, with Staphylococcus spp. and Bacillus spp. being the most common. Escherichia coli and Acinetobacter spp. were the most frequently recovered Gram-negative bacteria. E5 oncoprotein was detected in 86 of the 108 urothelial tumors under study. In the majority of cases, bacterial agents and BPV-2 E5 were simultaneously detected. A marked down-regulation of Tamm-Horsfall protein was also observed in the examined cases. In addition, the p65 subunit of the nuclear factor-κB (NF-κB) transcription factor appeared to be overexpressed. In all cases, a mild to severe chronic inflammation was evident in the stroma of urinary bladder tumors. Bacterial components may play a role in the activation of the NF-κB and might cause chronic inflammation resulting in an impaired ability to clear BPV-2 infection, thus cooperating with the virus in cancer development. As in man, therefore, bacteria could play both a direct and an indirect role in bovine bladder carcinogenesis.

Protective role of α-galactosylceramide-stimulated natural killer T cells in genital tract infection with Chlamydia muridarum

Natural killer T (NKT) cells are a unique lymphocyte subpopulation which has an important role in the response to microbial pathogens. In this study, we used α-galactosylceramide (α-GalCer), a specific ligand of NKT cells, to enhance NKT response and examine its effect on host defense against genital tract Chlamydia muridarum infection. The results showed that α-GalCer treatment before infection led to reduced pathological changes and bacterial burden in the genital tract. Moreover, α-GalCer-treated mice showed greater local Th1 cytokine production [interferon γ (IFN-γ) and interleukin 12 (IL-12)] in local lymph node cells and genital tissues following challenge infection compared with untreated mice, as well as an enhanced level of IFN-γ production by NK and T cells. In addition, NKT cells in the mice with genital tract C. muridarum infection, unlike those from naïve mice, showed a polarized IFN-γ production. These results suggest a promoting role of NKT cells on type 1 T cell immune response and host resistance to Chlamydia in genital tract infection.

Chlamydia trachomatis infections of the female genital tract: state of the art

Chlamydia trachomatis (CT) is the most common bacterial cause of sexually transmitted infections. CT infections are strongly associated with risk-taking behavior. Recommendations for testing have been implemented in many countries. The effectiveness of the screening programs has been questioned since chlamydia rates have increased. However, the complication rates including pelvic inflammatory disease, tubal factor infertility, and tubal pregnancy have been decreasing, which is good news. The complication rates associated with CT infection have clearly been over-estimated. Genetic predisposition and host immune response play important roles in the pathogenesis of long-term complications. CT plays a co-factor role in the development of cervical neoplasia caused by high-risk human papillomavirus (HPV) types. The evidence linking CT and other adverse pregnancy outcomes is weak. The current nucleic acid amplification tests perform well. A new genetic variant of CT was discovered in Sweden but has only rarely been detected elsewhere. Single-dose azithromycin remains effective against CT. Secondary prevention by screening is still the most important intervention to limit the adverse effects of CT on reproductive health.

Age-group differences in human papillomavirus types and cofactors for cervical intraepithelial neoplasia 3 among women referred to colposcopy

BACKGROUND

Recommendations for high-risk human papillomavirus (HR-HPV) testing as an adjunct to cytology for cervical cancer screening differ by age group, because HR-HPV tests lack adequate specificity in women aged <30. Here, we assess age-group differences in HPV types and other risk factors for cervical intraepithelial neoplasia (CIN) grade 3 or worse (CIN3+) versus CIN0-2 in women from four colposcopy clinics.

METHODS

Women ages 18 to 69 (n = 1,658) were enrolled and completed structured interviews to elicit data on behavioral risk factors prior to their examinations. HPV genotyping was done on exfoliated cervical cell samples. We estimated relative risks (RR) for HPV types and cofactors for CIN3+, overall and stratified by age group.

RESULTS

After 2 years of follow-up, we identified 178 CIN3+, 1,305 CIN0-2, and 175 indeterminate outcomes. Nonvaccine HR-HPV types were only associated with CIN3+ among women ≥ 30 (RR = 2.3, 95% CI: 1.5-3.4; <30: RR = 0.9). Among all HR-HPV-positive women, adjusting for age, significant cofactors for CIN3+ included current smoking (RR = 1.5), former smoking (RR = 1.8), regular Pap screening (RR = 0.7), current regular condom use (RR = 0.5), and parity ≥ 5 (RR = 1.6, P(trend) for increasing parity = 0.07). However, the parity association differed by age group (≥ 30: RR = 1.8, P(trend) = 0.008; <30: RR = 0.9; P(trend) =.55).

CONCLUSION

Subgroup variation by age in the risk of CIN3+ points to the importance of the timing of exposures in relation to CIN3+ detection.

IMPACT

Future screening strategies need to consider natural history and secular trends in cofactor prevalence in the pursuit of appropriately sensitive and specific screening tools applied to appropriate age groups.

The LMP7-K allele of the immunoproteasome exhibits reduced transcript stability and predicts high risk of colon cancer

Destruction of cancer cells by cytotoxic T lymphocytes depends on immunogenic tumor peptides generated by proteasomes and presented by human leukocyte antigen (HLA) molecules. Functional differences arising from alleles of immunoproteasome subunits have not been recognized so far. We analyzed the genetic polymorphism of the immunoproteasome subunits LMP2 and LMP7 and of the transporters associated with antigen processing (TAP1 and TAP2) in two independently collected panels of colorectal carcinoma patients (N(1) = 112, N(2) = 62; controls, N = 165). High risk of colon cancer was associated with the LMP7-K/Q genotype (OR = 8.10, P = 1.10 × 10(-11)) and low risk with the LMP7-Q/Q genotype (OR = 0.10, P = 5.97 × 10(-13)). The basis for these distinct associations of LMP7 genotypes was functionally assessed by IFN-γ stimulation of colon carcinoma cell lines (N = 10), followed by analyses of mRNA expression of HLA class I, TAP1, TAP2, and LMP7, with real-time PCR. Whereas induction of HLA-B, TAP1, and TAP2 was comparable in all cell lines, transcript amounts of LMP7-Q increased 10-fold, but of LMP7-K only 3.8-fold. This correlated with a reduced transcript stability of LMP7-K (t(1/2) ≈ 7 minutes) compared with LMP7-Q (t(1/2) ≈ 33 minutes). In addition, LMP7-Q/Q colon carcinoma cells increased (the peptide based) HLA class I surface expression significantly after IFN-γ stimulation, whereas LMP7-Q/K and LMP7-K/K carcinoma cells showed minimal (<20%) changes. These results suggest that the presence of LMP7-K can reduce the formation of immunoproteasomes and thus peptide processing, followed by reduced peptide-HLA presentation, a crucial factor in the immune response against cancer.

[Evaluation of the cobas 4800 CT/NG test for detecting Chlamydia trachomatis]

INTRODUCTION

To evaluate the new automated system cobas 4800 CT/NG test for detection of Chlamydia trachomatis in urogenital specimens.

MATERIAL AND METHODS

We analyzed 696 specimens (488 swabs from urethral or cervical specimens, and 208 urines) to detect C. trachomatis. The results of the cobas 4800 CT/NG test (c4800) were compared to those obtained with Cobas AMPLICOR CT/NG test (CAM). Discordant results were analyzed with a conventional PCR assay and microchip electrophoresis system in agarose gel, MultiNA.

RESULTS

We made two simultaneous analyses. In the first one, we compared the results obtained with swab specimens using the c4800 system and CAM. In this case, the sensitivity, the specificity, the positive and negative predictive values (PPV and NPV) were: 77.9%, 100%, 100% and 96% respectively. In the second one, we compared the results obtained for urine and its corresponding swab specimens on the c4800. The values obtained were: 100%, 98.9%, 92.9% and 100% respectively. The kappa values of these comparisons were: 0.857 for swab specimens on the c4800 and CAM, and 0.957 for urine versus swab specimens on the c4800.

CONCLUSIONS

The results obtained with c4800 system were completely comparable with those obtained with CAM. We also noted an excellent correlation with these results when we compared swab specimens with their urine samples in the c4800 system. Therefore this sample type could be used routinely to diagnose infections in men and women.

Chlamydia trachomatis infection and risk of cervical intraepithelial neoplasia

Objectives

High-risk human papillomavirus (hrHPV) is the primary cause of cervical cancer. As Chlamydia trachomatis is also linked to cervical cancer, its role as a potential co-factor in the development of cervical intraepithelial neoplasia (CIN) grade 2 or higher was examined.

Methods

The placebo arms of two large, multinational, clinical trials of an HPV6/11/16/18 vaccine were combined. A total of 8441 healthy women aged 15–26 years underwent cervicovaginal cytology (Papanicolaou (Pap) testing) sampling and C trachomatis testing at day 1 and every 12 months thereafter for up to 4 years. Protocol-specified guidelines were used to triage participants with Pap abnormalities to colposcopy and definitive therapy. The main outcome measured was CIN.

Results

At baseline, 2629 (31.1%) tested positive for hrHPV DNA and 354 (4.2%) tested positive for C trachomatis. Among those with HPV16/18 infection (n=965; 11.4%) or without HPV16/18 infection (n=7382, 87.5%), the hazard ratios (HRs) associated with development of any CIN grade 2 according to baseline C trachomatis status were 1.82 (95% CI: 1.06 to 3.14) and 1.74 (95% CI 1.05 to 2.90), respectively. The results were comparable when only the 12 most common hrHPV infections were considered, but the excess risk disappeared when the outcome was expanded to include CIN grade 3 or worse.

Conclusion

Further studies based on larger cohorts with longitudinal follow-up in relation to the C trachomatis acquisition and a thorough evaluation of temporal relationships of infections with hrHPV types, C trachomatis and cervical neoplasia are needed to demonstrate whether and how in some situations C trachomatis sets the stage for cervical carcinogenesis.

Trial registration

NCT00092521 and NCT00092534.

The prevalence of abnormal cervical cytology in women with infertility

The aim of this study was to compare the frequency of abnormal cervical cytology in women with infertility problems with that of fertile women by using ThinPrep® liquid-based Pap Tests™. A retrospective case-control study for over 2 years was conducted. The cases included all women with infertility problems who had Pap tests during their infertility treatment period. The cases were further subdivided into primary and secondary infertility groups. The control group included all women without infertility problems who had routine Pap tests in the same period. The age and demographic features were adjusted and matched for both groups. Statistical analysis included chi-square test and Fischer exact test. The infertility group (n = 490) showed significantly (P < 0.05) more abnormal cervical squamous epithelial abnormalities (48 positive cases, 9.8%) than the controls (n = 7,150, 216 positive cases, 3%). Women with secondary infertility had more epithelial abnormalities and more high-grade lesions than women with primary infertility. Women with infertility had statistically significant higher frequency of squamous intraepithelial lesions than women without infertility problems of similar age and demographic background. The data suggest that women with infertility might benefit from more frequent cervical cytology screening.

Prevalence and patient characteristics associated with CIN 3 in adolescents

OBJECTIVE

We sought to identify patient characteristics associated with cervical intraepithelial neoplasia (CIN) 3 in adolescents.

STUDY DESIGN

A cross-sectional cohort study was done using a colposcopic database. Data collected included demographic and clinical information as well as cytologic and histologic results. Variables associated with CIN 3 in the univariable analysis (P ≤ .10) were included in a multivariable logistic regression model.

RESULTS

Of 614 adolescents evaluated, 48 (8%; 95% confidence interval, 6-10%) had CIN 3. No cancers were detected. In the univariable analysis, parity, ≥ 4 lifetime male sexual partners, and a history of sexually transmitted infections were associated with an increased risk of CIN 3. In the final model, only ≥ 4 sexual partners (compared to <4; adjusted odds ratio, 3.66; 95% confidence interval, 1.26-10.61) was significantly associated with the finding of CIN 3.

CONCLUSION

CIN 3 was infrequently encountered in adolescents, and those with multiple sexual partners were at increased risk for CIN 3.

Role of bacteria in oncogenesis

Although scientific knowledge in viral oncology has exploded in the 20th century, the role of bacteria as mediators of oncogenesis has been less well elucidated. Understanding bacterial carcinogenesis has become increasingly important as a possible means of cancer prevention. This review summarizes clinical, epidemiological, and experimental evidence as well as possible mechanisms of bacterial induction of or protection from malignancy.

Detection of Human Papilloma Virus (HPV) in oral mucosa of women with cervical lesions and their relation to oral sex practices

Background

Previous studies have either investigated the relationship of HPV with oral cancer or the prevalence of HPV on the oral cavity. The purpose of this investigation was to study the prevalence of HPV in oral cavity of women with oral sex practices and cervical lesions.

Methods

Forty six (46) non-smokers and non-alcoholic patients attended the "Clínica de Displasias" of "Ciudad Juarez" were sampled. This population had a CIN diagnosis sometime between the previous six months. On previous consent they filled out a questionnaire related to their oral sex practices. Afterwards one swab from cheeks and another from palate/gum were taken; PCR was used to determine generic HPV, HPV16 and HPV18.

Results

Seventy two percent (72%) of the patients stated to have oral sex practices regularly which all of them were positive to HPV either in oral mucus, palate/gum or both. The total of the given results showed that 35% had HPV16; among those distributed in 26% with regular oral sex practices and 9% stated as never practiced oral sex. An association was found between oral HPV16 positivity and progression to cervical CIN advanced lesions. On the other hand HPV18 was not detected. The frequency of HPV16 was higher in buccal mucosa (23%) versus palate/gum (16%).

Conclusions

This study suggests that buccal HPV16 infection is associated with CIN progression.

Factors affecting transmission of mucosal human papillomavirus

Human papillomavirus (HPV) is the most common sexually transmitted infection. The effect of HPV on public health is especially related to the burden of anogenital cancers, most notably cervical cancer. Determinants of exposure to HPV are similar to those for most sexually transmitted infections, but determinants of susceptibility and infectivity are much less well established. Gaps exist in understanding of interactions between HPV, HIV, and other sexually transmitted infections. The roles of mucosal immunology, human microbiota at mucosal surfaces, host genetic factors and hormonal concentrations on HPV susceptibility and infectivity are poorly understood, as are the level of effectiveness of some primary or secondary preventive measures other than HPV vaccination (such as condoms, male circumcision, and combination antiretroviral therapy for HIV). Prospective couples studies, studies focusing on mucosal immunology, and in-vitro raft culture studies mimicking HPV infection might increase understanding of the dynamics of HPV transmission.

The prevalence of abnormal cervical cytology in women with systemic lupus erythematosus

To compare the frequency of abnormal cervical cytology in women with systemic lupus erythematosus (SLE) with that of healthy women without connective tissue diseases by using ThinPrep® liquid based Pap Tests(TM) . A retrospective case-control study over 2 years was conducted. The cases included all women with SLE who had Pap tests during their treatment period. The control group included all women without SLE or other connective tissue diseases (CTDs) that had routine Pap tests in the same period. The age and demographic features were adjusted and matched for both groups. Statistical analysis included Chi-Square test and Fischer exact test. The SLE group (n= 55) showed significantly (P < 0.05) more abnormal cervical squamous epithelial abnormalities [14 positive cases (25.4%) than the controls (n = 8,175, with 285 positive cases (3.5%)]. Women with SLE had statistically significant higher frequency and prevalence of squamous intraepithelial lesions than women without SLE of similar age and demographic background. The data suggested that women with SLE might benefit from more frequent cervical cytology screening.

Monitoring of human papillomavirus vaccination

Persistent infection with oncogenic human papillomavirus (HPV) is a necessary causal factor in the development of cervical cancer. Moreover, HPV, predominately type 16 and to a lesser degree type 18, is linked causally to varying proportions of other anogenital cancers (vulva, vagina, penis, anus) as well as cancers elsewhere in the body (oropharynx, larynx, conjunctiva). HPV types 6 and 11 cause most of genital warts and recurrent respiratory papillomatosis. Effective prophylactic vaccines have been developed. In this review, we address briefly the immunological aspects of HPV infection and the results of HPV vaccination trials. Internationally standardized monitoring and evaluation of prophylactic HPV vaccination programmes will be essential for arriving at the most cost-effective strategies for cancer control.

Detection of sexually transmitted infection and human papillomavirus in negative cytology by multiplex-PCR

Background

The aim of this study was to determine the prevalence of human papillomavirus (HPV) and 15 species that cause sexually transmitted infections (STIs) in negative cytology. In addition, we compared the diagnostic performance of multiplex polymerase chain reaction (PCR) with widely available techniques used to detect HPV.

Methods

We recruited 235 women of reproductive age who had negative cytology findings in a liquid-based cervical smear. STIs were identified by multiplex PCR, and HPV genotypes by multiplex PCR, hybrid capture 2, and DNA microaray; discordant results were analyzed by direct sequencing.

Results

Approximately 96.6% of patients with negative cytology results were positive for pathogens that cause STIs. The pathogens most frequently detected were Gardnerella vaginalis, Ureaplasma urealyticum. The incidence of HPV in negative cytology was 23.3%. Low-risk HPV infection was significantly correlated with Chalmaydia trachomatis, and high-risk HPV infection was significantly correlated with Group β streptococcus. The analytical sensitivities of the multiplex PCR and DNA microarray were higher than 80%, and the analytical specificity was nearly 100% for all tests.

Conclusions

Multiplex PCR yielded results that most of patients with negative cytology were positive for pathogens that cause STIs, and were more similar to that of DNA microarray, than that of hybrid capture 2 in terms of analytical sensitivity and prediction value of HPV infection.

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.

Persistence of high-risk human papillomavirus infection in a population-based cohort of Danish women

Persisting human papillomavirus (HPV) infection is a critical step in cervical carcinogenesis. This study was conducted to determine the type-specific HPV persistence and risk factors for persistence of high-risk HPV infections in a large cohort of Danish women. The study was based on a population-based prospective cohort study of women aged 20-29 years. Participants were interviewed and underwent two gynecological examinations 2 years apart. Women with Hybrid Capture 2 results at enrolment and a follow-up visit were included in the analysis (n = 7,418). Persistence was defined as positivity for the same high-risk HPV type at both examinations. Overall, 4.2% of the women had persistent HPV infection, accounting for 26.9% of the initially HPV-positive women. HPV 16, HPV 58, and HPV 31, all from species group alpha 9, were the most persistent types; however, other high-risk HPV types that are detected rarely in cancer cases were also likely to persist. The number of high-risk HPV types and detection of HPV 16 infection at baseline and ever use of oral contraceptives increased the risk for persistence. The risk factor analyses also showed that use of an intrauterine device decreased the risk for persistent high-risk HPV infection among women with one high-risk HPV type at baseline. No association was found with viral load or smoking. In conclusion, persistent high-risk HPV infection, especially HPV 16 persistence, was common among women positive for high-risk HPV.

Predictors of human papillomavirus persistence among women with equivocal or mildly abnormal cytology

We investigated short-term persistence of human papillomavirus (HPV) infection among 2,408 women with low-grade or equivocal cytological abnormalities followed for 24 months. Odds ratios (ORs) for persistence to the next 6-month visit were estimated by a discrete time survival model. Prevalent HPV infections persisted longer in older women, but no association with age was found for incident HPV infections. Increased likelihood of persistence was found among current smokers of >20 cigarettes per day compared with smokers of <or=10 cigarettes per day (OR=1.43; 95% confidence interval [CI]: 1.02-2.01) and among current injectable contraceptive users (OR=1.15; 95% CI: 1.01-1.32). Persistence was more likely among infections with higher viral load (OR=2.05; 95% CI: 1.65-2.53) or with concurrent cytological abnormalities (OR=1.19; 95% CI: 1.03-1.39 and 1.29; 95% CI: 0.99-1.70 for ASCUS/LSIL and ASC-H/HSIL, respectively). We conclude that new HPV infections in older women are not riskier by the metric of viral persistence than those in younger women. Other risk factors such as oral contraceptive use and multiparity that have been associated with cervical cancer or cervical intraepithelial neoplasia grade 3 were not associated with short-term HPV persistence.

Centrosome abnormalities during a Chlamydia trachomatis infection are caused by dysregulation of the normal duplication pathway

The presence of supernumerary centrosomes in cells infected with Chlamydia trachomatis may provide a mechanism to explain the association of C. trachomatis genital infection with cervical cancer. We show that the amplified centrosomal foci induced during a chlamydial infection contain both centriolar and pericentriolar matrix markers, demonstrating that they are bona fide centrosomes. As there were multiple immature centrioles but approximately one mature centriole per cell, aborted cytokinesis alone cannot account for centrosome amplification during a chlamydial infection. Production of supernumerary centrosomes required the kinase activities of Cdk2 and Plk4, which are known regulators of centrosome duplication, and progression through S-phase, which is the stage in the cell cycle when duplication of the centrosome occurs. These requirements indicate that centrosome amplification during a chlamydial infection depends on the host centrosome duplication pathway, which normally produces a single procentriole from each template centriole. However, C. trachomatis induces a loss of numerical control so that multiple procentrioles are formed per template.

Natural history of human papillomavirus infections, cytologic and histologic abnormalities, and cancer

Over 100 human papillomavirus (HPV) types have been identified to date, of which over 40 infect the genital tract, primarily through sexual transmission. The many different genital HPV types appear to infect, resolve, or persist, and cause abnormal cytology and cervical intraepithelial neoplasia. Several cofactors have been associated with HPV persistence and lesion progression, including smoking, long-term oral contraceptive use, other sexually transmitted infections, host immunogenetics, and viral factors, such as HPV type and HPV variants. Given the discovery of HPV as the single primary cause of invasive cervical cancer, primary and secondary interventions have been realized, including HPV testing in cervical screening programs and prophylactic HPV vaccines. Because first generation HPV vaccines only target the two most common HPV types found in cervical cancer (HPV 16 and 18), cervical screening programs must continue, and the relative roles of HPV vaccination in young women and HPV testing in older women (alone or in conjunction with cytology) will be determined over the next decades.

Prevalence, acquisition, and clearance of cervical human papillomavirus infection among women with normal cytology: Hawaii Human Papillomavirus Cohort Study

Few natural history studies of cervical human papillomavirus (HPV) incidence and duration have been conducted among older women, especially from multiethnic populations. Viral and nonviral determinants of HPV acquisition and clearance were examined among 972 sexually active women, ages 18 to 85 years, recruited from clinics on Oahu, Hawaii, and followed for a mean duration of 15 months (range, 2-56 months). Interviews and cervical cell specimens for cytology and HPV DNA detection by PCR, using the PGMY09/PGMY11 primer system, were obtained at baseline and at 4-month intervals. The prevalence of cervical HPV infection was 25.6% at study entry. A total of 476 incident genotype-specific infections were observed during the follow-up period. The incidence of high-risk (HR) HPV types (9.26 per 1,000 woman-months) was similar to low-risk (LR) HPV types (8.24 per 1,000 woman-months). The most commonly acquired HR-HPV types were HPV-52, HPV-16, and HPV-31; and their incidence was increased significantly with a coexisting cervical HPV infection. Cervical HPV acquisition decreased with age, income, and long-term use of oral contraceptives and increased with number of sexual partners, use of hormonal creams, alcohol drinking, and condom use by a sexual partner. Cohort participants cleared 265 of the 476 incident infections during follow-up. LR-HPV infections cleared more rapidly than did HR-HPV infections (median, 180 days versus 224 days). Clearance times were enhanced among older women and women with multiple infections. Our data suggest several viral and nonviral determinants of cervical HPV acquisition and clearance that might be used in cervical cancer prevention programs.

Evaluation of a novel PCR-based assay for detection and identification of Chlamydia trachomatis serovars in cervical specimens

The aims of this study were to compare a novel PCR-based Chlamydia trachomatis detection and genotyping (Ct-DT) assay with the FDA-approved, commercially available C. trachomatis detection Hybrid Capture 2 (HC2) assay and to investigate the C. trachomatis serovar distribution among young women in a rural Costa Rican study population. A total of 5,828 sexually active women participating in a community-based trial in Costa Rica were tested for C. trachomatis by HC2. A sample of 1,229 specimens consisting of 100% HC2 C. trachomatis-positive specimens (n = 827) and a random sample of 8% HC2 C. trachomatis-negative specimens (n = 402) were tested with the Ct-DT assay. Agreement between the two assays was determined by the unweighted kappa statistic. Discrepant specimens were tested with a second commercially available test (COBAS TaqMan). The Ct-DT-positive specimens were further analyzed with the Ct-DT genotyping step to investigate the distribution of 14 different C. trachomatis serovars (A, B/Ba, C, D/Da, E, F, G/Ga, H, I/Ia, J, K, L1, L2/L2a, and L3). After accounting for the sampling fraction selected for Ct-DT testing, crude agreement with the HC2 assay was 98% and the kappa was 0.92 (95% confidence interval [CI], 0.89 to 0.97). The 33 discordant samples that were further analyzed with the COBAS TaqMan test showed better agreement with the Ct-DT assay (31/33, P < 0.001). Among the 806 Ct-DT-positive samples, serovar E was the most common serovar (31%), followed by serovars F and D (both 21%) and serovar I (15%). In conclusion, the novel Ct-DT assay permits reliable detection and identification of C. trachomatis serovars.

A highly sensitive, multiplex broad-spectrum PCR-DNA-enzyme immunoassay and reverse hybridization assay for rapid detection and identification of Chlamydia trachomatis serovars

Chlamydia trachomatis (Ct) comprises distinct serogroups and serovars. The present study evaluates a novel Ct amplification, detection, and genotyping method (Ct-DT assay). The Ct-DT amplification step is a multiplex broad-spectrum PCR for the cryptic plasmid and the VD2-region of ompl. The Ct-DT detection step involves a DNA enzyme immunoassay (DEIA) using probes for serogroups (group B, C, and intermediate) and the cryptic plasmid, permitting sensitive detection of 19 Ct serovars (A, B/Ba, C, D/Da, E, F, G/Ga, H, I/Ia, J, K, L1, L2/L2a, and L3) without any cross-reactivity with other Chlamydia species and pathogenic bacteria or commensal organisms of the genital tract. Ct-positive samples are analyzed by a nitrocellulose-based reverse hybridization assay (RHA) containing probes for the 19 different serovars and for the cryptic plasmid. The sensitivity of the PCR-DEIA on clinical specimen is equivalent to that of the Cobas TaqMan assay [kappa = 0.95 (95% confidence interval = 0.92 to 0.99)]. Using the RHA, 98% of the Ct-DT detection step-positive samples could be typed. Analysis of cervical swabs from Uganda and The Netherlands revealed that the most common serovars in Uganda are G/Ga (45%), E (21%), K (13%), and F (8%), and in The Netherlands serovars E (38%), F (23%), G/Ga (11%), and D/Da (7%) were most common. Thus, multiplex broad-spectrum PCR in combination with DEIA and RHA permits highly sensitive and specific detection and identification of Ct serovars.

Translational mini-review series on vaccines: Monitoring of human papillomavirus vaccination

Persistent infection with oncogenic human papillomavirus (HPV) is a necessary cause of cervical cancer. Moreover, HPV type 16 (and to a lesser degree HPV type 18) is linked with more rare cancers, namely cancer of the vulva, vagina, penis, anus, oropharynx and larynx. Effective prophylactic vaccines have been developed. In this review, we briefly address immunological aspects of HPV infection and the results of HPV vaccination trials. Internationally standardized monitoring and evaluation of prophylactic HPV vaccination programmes will be essential for arriving at the most (cost-)effective strategies for cancer control.

Seroprevalence of human papillomaviruses and Chlamydia trachomatis and cervical cancer risk: nested case-control study

A nested case-control study of invasive and in situ cervical cancer was performed within a community-based cohort of 13,595 Taiwanese women assembled in 1991, with a follow-up period of 9 years. Baseline serum or plasma samples were analysed for antibodies against human papillomavirus (HPV) types 6, 16 and 18 and Chlamydia trachomatis. In total, 114 cases (42 incident cases identified during follow-up and 72 prevalent cases identified at baseline) and 519 matched controls were included in the study. HPV-16 seropositivity was strongly associated with cervical cancer (OR=6.33; 95% CI 3.45-11.62). Overall, C. trachomatis was not associated with cervical cancer, but was associated with cervical cancer in analyses restricted to incident cases of cancer (OR=2.94; 95% CI 1.17-7.42) or to cases in which serum samples were analysed (OR=3.13; 95% CI 1.16-8.47). An antagonistic interaction between HPV-6 and -16 was found in a multiplicative model. These results suggest that different HPV types might interfere in cervical carcinogenesis and that C. trachomatis is associated with cervical cancer in prospective studies, and support the notion that HPV-16 seropositivity is strongly associated with cervical cancer.

Codon usage bias in Chlamydia trachomatis and the effect of codon modification in the MOMP gene on immune responses to vaccinationThis paper is one of a selection of papers in this Special Issue, entitled International Symposium on Recent Advances in Molecular, Clinical, and Social Medicine, and has undergone the Journal's usual peer-review process

Chlamydia trachomatis is a kind of obligate intracellular bacterial pathogen that causes ocular and sexually transmitted diseases. In this study, we analyzed the codon usage patterns of the C. trachomatis mouse pneumonitis biovar (MoPn) and Homo sapiens. We found large differences between MoPn and human codon usages. To enhance the expression of Chlamydia protein in mammalian cells, the DNA sequence encoding the major outer-membrane protein (MOMP) of MoPn was modified to substitute the human-preferred codons for rarely used codons. The huma-optimized MOMP gene was synthesized and cloned into the pcDNA3 vector, as was the wild-type MOMP gene. The protein expression levels of the human-optimized MOMP and wild-type MOMP genes were compared. The experiments showed that the human-optimized MOMP gene produced significantly higher levels of MOMP protein than the wild-type MOMP, both in vitro and in vivo, but no obvious difference was observed in the levels of modified and native MOMP mRNA expression. The immunogenicity of the 2 constructs was examined using BALB/c mice following intramuscular immunization. The results showed that the mice immunized with the human-optimized MOMP produced higher levels of antigen-specific IgG antibody and showed stronger delayed-type hypersensitivity reactions and proliferative T cell responses than those immunized with the wild-type MOMP. Antigen-specific stimulation of spleen cells obtained from human MOMP DNA immunized mice produced higher levels of interferon-gamma than those obtained from wild-type MOMP DNA immunized mice. Taken together, the data show that human-optimized codon optimization can significantly enhance the gene expression and immunogenicity of the C. trachomatis MOMP DNA vaccine.

Risk of cervical cancer associated with Chlamydia trachomatis antibodies by histology, HPV type and HPV cofactors

Human papillomavirus (HPV) is the central etiologic factor for cervical cancer, and prior studies suggested C. trachomatis may act as an HPV cofactor. We examined the C. trachomatis-cervical cancer association by serotype, histology, HPV type in the tumor, and other HPV cofactors. We conducted a population-based study in the Seattle-Puget Sound area of 302 women with invasive squamous cell carcinomas (SCC), 185 women with adenocarcinomas of the cervix (AC), and 318 HPV seropositive control women. The risk of SCC associated with antibodies to C. trachomatis was increased (OR 1.6, 95% CI 1.1-2.2) but not for AC (OR 1.0, 95% CI 0.6-1.5). This association was independent of HPV type in the SCC tumor tissue. There was an association between specific serotypes of C. trachomatis and SCC for 6 of the 10 serotypes: B (OR 3.6, 95% CI 1.5-8.4), D (OR 2.1, 95% CI, 1.2-3.5), E (OR 2.4, 95% CI, 1.4-3.9), G (OR 3.0, 95% CI, 1.1-7.9), I (OR 4.2, 95% CI, 1.5-11.7), and J (OR 2.3, 95% CI, 1.0-5.1), but not for the 4 types (C, F, H, and K) that were present at very low prevalence in this population. There was an increased risk of SCC, but not AC, associated with antibodies to C. trachomatis that was not serotype specific.

Cervical screening in the 21st century: the case for human papillomavirus testing of self-collected specimens

Cervical screening by Pap smear involves a high rate of false negatives, necessitating frequent testing. Because women do not like the sampling procedure, many avoid being screened. Testing for the causative high-risk human papillomavirus (HPV) types, by PCR or other technologies, on self-collected (tampon) samples permits women to be monitored non-invasively. The high negative predictive value of HPV testing means a greater interval between tests, and thus reduces costs. HPV testing lends itself to primary screening. A kit for self-collection and return to a testing laboratory, followed by practitioner notification and follow-up if required, should result in wider participation. The higher accuracy of HPV testing should lead to improved cervical cancer prevention.

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.

Aetiology, diagnosis and therapy of sexually transmitted and allied infections--reflections on novel observations and current trends

The present communication highlights aspects on the aetiology, diagnosis and therapy of sexually transmitted infections (STIs) and some allied infections in which sexual transmission is regarded as possible. The aetiology of many genital infections is still unknown or rather, an aetiological relationship between a given agent and a clinical manifestation is in some infections still debated. The paper will discuss some shortcomings in the current surveillance systems for STIs, if these systems exist at all. Thus, the paper considers their value in estimating the extent of the problem on a general population basis. It also focuses on the discrepancy between the current high prevalence of diagnosed cases of some STIs, such as of genital chlamydia infections, and the relatively low number of complications and sequelae presently seen, in contrast to the comparatively high prevalence more commonly reported in the past. Recent discoveries of novel aetiological agents of STIs, including mycoplasmas, may explain a lack of recovery from infections, due to the common use of antibiotic drugs to which these agents have a natural resistance. The observation of a synergistic effect of a commonly used anti-inflammatory drug, which may overcome antifungal resistance in vulvovaginal candidiasis, will also be reviewed. Furthermore, other reflections concern some of the classic STIs, e.g. lymphogranuloma verenerium, syphilis, gonorrhoea, herpes and condyloma.

Relationship between prevalent oral and cervical human papillomavirus infections in human immunodeficiency virus-positive and -negative women

Human papillomavirus (HPV) is an etiologic agent for both oropharyngeal and cervical cancers, yet little is known about the interrelationship between oral and cervical HPV infections. Therefore, we compared the prevalences and type distributions of oral and cervical HPV infections and evaluated infection concordance in a cross-sectional study within the Women's Interagency HIV Study cohort. Oral rinse and cervical-vaginal lavage samples were concurrently collected from a convenience sample of 172 human immunodeficiency virus (HIV)-positive and 86 HIV-negative women. HPV genomic DNA was detected by PGMY09/11 L1 consensus primer PCR and type specified by reverse line blot hybridization for 37 HPV types and beta-globin. Only 26 of the 35 HPV types found to infect the cervix were also found within the oral cavity, and the type distribution for oral HPV infections appeared distinct from that for cervical infections (P<0.001). Oral HPV infections were less common than cervical infections for both HIV-positive (25.2% versus 76.9%, P<0.001) and HIV-negative (9.0% versus 44.9%, P<0.001) women. Oral HPV infections were more common among women with a cervical HPV infection than those without a cervical HPV infection (25.5% versus 7.9%, P=0.002). The majority of women (207; 93.7%) did not have simultaneous oral and cervical infections by the same HPV type; however, the number of women who did (14; 6.3%) was significantly greater than would be expected by chance (P=0.0002). Therefore, the oral and cervical reservoirs for HPV infection are likely not entirely independent of one another.