A meta-analysis of the relationship between vaginal microecology, human papillomavirus infection and cervical intraepithelial neoplasia

Microecology is an emerging discipline in recent years. The female reproductive tract is an important microecological region, and its microecological environment can directly affect women's cervical health. This meta-analysis aimed to analyze the effects of vaginal microecology on Human papillomavirus (HPV) infection and cervical intraepithelial neoplasia (CIN). PubMed and Web of Science were systematically searched for eligible publications from January 2000 to December 2017. Articles were selected on the basis of specific inclusion and exclusion criteria. The design and quality of all studies were evaluated using the Newcastle-Ottawa Scale (NOS). Odds ratios (ORs) with a 95% confidence interval (95% CI) were calculated. Thirteen eligible studies were selected to evaluate the association of vaginal microecology with HPV infection and CIN. The factors related to HPV infection were bacterial vaginosis (BV) (OR 2.57, 95% CI 1.78-3.71, P<0.05), Candida albicans (VVC) (OR 0.63, 95% CI 0.49-0.82, P < 0.05), Chlamydia trachomatis (CT) (OR 3.16, 95% CI 2.55-3.90, P < 0.05), and Ureaplasma urealyticum (UU) (OR 1.35, 95% CI 1.20-1.51, P < 0.05). BV was also related to CIN (OR 1.56, 95% CI 1.21-2.00, P < 0.05). This meta-analysis of available literature suggested an intimate association of vaginal microecology and HPV infection with CIN. BV, CT and UU were associated to increased HPV infection, VVC was associated to decreased HPV infection, Lactobacillus is not associated to increased HPV infection, BV was associated to increased CIN development risk. Further large-scale studies are needed to confirm our findings.

Human papillomavirus as an independent risk factor of invasive cervical and endometrial carcinomas in Jordan

BACKGROUND

Endometrial and cervical carcinomas are the most common gynecologic malignancies in Western world and many countries. The human papillomavirus (HPV) high-risk genotypes are associated with cervical carcinoma (CC). Chlamydia trachomatis (C. trachomatis), the most common sexually transmitted bacterial infection worldwide, considered a cofactor for HPV infection and CC. Information on HPV infection rate and type distribution among Jordanian women having CC is currently limited and unavailable among those with endometrial carcinoma. Therefore, the present study aimed to provide an updated estimate on HPV infection rate and its high-risk genotypes' distribution among Jordanian women by comparing data from invasive cervical carcinoma (ICC) to normal cervical tissues. Similarly, assessment of HPV infection rate was extended to the endometrial tissues. C. trachomatis infection was investigated as well to explore its possibility as HPV cofactor for induction of such carcinomas.

METHODS

Total DNA was extracted from 144 formaldehyde-fixed paraffin-embedded cervical and endometrial tissue, equally divided between age-matched control and carcinoma cases. Polymerase chain reaction (PCR) was used for general detection of HPV-DNA, high risk HPV-16 and 18 genotypes and C. trachomatis DNA using specific primers.

RESULTS

HPV infection was detected in 91.7% and 61.1% of cervical cancer patients and controls, respectively. Likewise, it was higher among cases (47.2%) than controls (13.8%) in endometrial biopsies. Significantly higher HPV infection rates were found among ICC and endometrial control biopsies of women >50 years. Out of 33 HPV positive ICC cases, single HPV-16 infections were detected in 69.7% compared to HPV-18 (15.2%), while HPV-16/18 co-infections were only found in three (9%) samples. C. trachomatis was not detected in all studied groups.

CONCLUSION

The present study has successfully provided an updated estimate on HPV infection rate among Jordanian women with and without ICC and endometrial carcinoma. In addition, a lack of co-infection was observed between HPV and C. trachomatis in both cancer types.

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.

Lack of association between Chlamydia trachomatis infection and cervical cancer--Taq Man realtime PCR assay findings

BACKGROUND

Cervical cancer is one of the most common cancers in developing countries and the second most common type of cancer in women globally. Several recent studies suggested a co factor role for Chlamydia trachomatis in pathogenesis of cervical cancer. This study aimed to evaluate existence of C. trachomatis DNA in pathologic blocks of patients with cervical cancer.

MATERIALS AND METHODS

Seventy-six formaldehyde fixed paraffin embedded tissue specimens from patients with histologically proven history of cervical cancer as well as 150 blocks from healthy peoples were included in the present study. Thin slices were prepared from selected blocks followed by deparaffinization and DNA extraction; the presence of C. trachomatis DNA was examined by Taq Man real-time PCR.

RESULTS

Our TaqMan real time PCR assay with cervical specimens of patients with cervical cancer showed that there was no C. trachomatis DNA. Also, we found three positive specimens among our control group.

CONCLUSION

It seems that based on results obtained from the specimens examined in the present study, there is no association between the presence of C. trachomatis DNA in cervical specimens and cervical cancer.