The Role of Chlamydia Trachomatis in the Pathogenesis of Cervical Cancer

Genital infections in high-risk human papillomavirus positive Paraguayan women aged 30-64 with and without cervical lesions

OBJECTIVE

To determine the prevalence of genital infections (GIs), including sexual transmitted STIs: Neisseria gonorrhoeae, Chlamydia trachomatis, Mycoplasma genitalium, Trichomonas vaginalis, and opportunistic pathogens that generally do not cause STIs, non-classic STI: Ureaplasma urealyticum, Ureaplasma parvum and Mycoplasma hominis, in women with high-risk oncogenic human papillomavirus (hr-HPV) infection and their association with cervical lesions.

METHODS

A cross-sectional study was carried out including 231 hr-HPV positive women. Of these, 46 has histologically confirmed cervical intraepithelial neoplasia 3 (CIN3) or more (including CIN3 and cervical cancer lesions-CIN3+). GIs were detected by multiplex real time PCR. Odds ratios (OR) were estimated to explore possible associations between GIs and the presence or absence of CIN3+ lesions. Additionally, we examined associations between sociodemographic, sexual, and clinical characteristics and the presence of GIs.

RESULTS

In total, there were 174/231 cases of GIs corresponding to an overall prevalence of 75.3% (95%CI: 69.4-80.4), being non-classic STIs the most common (72.3%) compared to STIs (12.6%). The most prevalent non-classic STI and STI were U. parvum (49.8%) and C. trachomatis (7.4%), respectively. The odds of presenting GIs were 3 times higher in women under 46 years compared to older counterparts (OR: 3.32, 95%CI: 1.74-6.16), and in women with a normal Pap smear with inflammation compared to those without inflammation (OR: 3.31, 95%CI: 1.15-9.77). GIs were equally present in women with and without CIN3+ lesions.

CONCLUSION

We observed an association of GIs with inflammation in the Pap smear, but no association with CIN3+, as some of them are very common and likely part of the normal vaginal flora, suggesting that such infections do not appear to be cofactors in cervical carcinogenesis, although larger prospective studies are needed.

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.

Evidence for the presence of Borrelia burgdorferi in invasive breast cancer tissues

Borrelia burgdorferi, the causative agent of Lyme disease, has recently been demonstrated to infect and enhance the invasive properties of breast cancer cells, while also influencing the expression of inflammatory chemokines (CXCL8 and CXCL10). This study investigates the presence of B. burgdorferi in invasive breast cancer tissues using commercially available, FDA-approved breast cancer tissue microarrays consisting of 350 ductal, 32 lobular, and 22 intraductal invasive breast carcinomas, alongside 29 normal breast tissues. Employing fluorescent immunohistochemical staining and high-resolution imaging, the findings revealed that approximately 20% of invasive lobular and ductal carcinomas, followed by 14% of intraductal carcinomas, tested positive for B. burgdorferi, while all normal breast tissues tested negative. PCR analysis further confirmed the presence of B. burgdorferi DNA in breast cancer tissues. Moreover, 25% of B. burgdorferi-positive tissues exhibited expression of both chemokines, CXCL8 and CXCL10, which was not observed in B. burgdorferi-negative tissues. Analysis of available patient data, including age, indicated a correlation between older patients and B. burgdorferi-positive tissues. This study validates the presence of B. burgdorferi in invasive breast cancer tissues and highlights the involvement of key CXCL family members associated with inflammatory processes.

Insights into innate immune cell evasion by Chlamydia trachomatis

Chlamydia trachomatis, is a kind of obligate intracellular pathogen. The removal of C. trachomatis relies primarily on specific cellular immunity. It is currently considered that CD4+ Th1 cytokine responses are the major protective immunity against C. trachomatis infection and reinfection rather than CD8+ T cells. The non-specific immunity (innate immunity) also plays an important role in the infection process. To survive inside the cells, the first process that C. trachomatis faces is the innate immune response. As the "sentry" of the body, mast cells attempt to engulf and remove C. trachomatis. Dendritic cells present antigen of C. trachomatis to the "commanders" (T cells) through MHC-I and MHC-II. IFN-γ produced by activated T cells and natural killer cells (NK) further activates macrophages. They form the body's "combat troops" and produce immunity against C. trachomatis in the tissues and blood. In addition, the role of eosinophils, basophils, innate lymphoid cells (ILCs), natural killer T (NKT) cells, γδT cells and B-1 cells should not be underestimated in the infection of C. trachomatis. The protective role of innate immunity is insufficient, and sexually transmitted diseases (STDs) caused by C. trachomatis infections tend to be insidious and recalcitrant. As a consequence, C. trachomatis has developed a unique evasion mechanism that triggers inflammatory immunopathology and acts as a bridge to protective to pathological adaptive immunity. This review focuses on the recent advances in how C. trachomatis evades various innate immune cells, which contributes to vaccine development and our understanding of the pathophysiologic consequences of C. trachomatis infection.

Interleukin-10 Gene Polymorphisms Modulate the Risk of Infertility in Chlamydia trachomatis Positive Kurdish Women in Erbil Province

Background

There is evident inter-individual variability in women's responses to Chlamydial infections and reproductive tract problems. Women's genetic variations within the Interleukin-10 (IL-10) gene have been linked to variances in response to Chlamydia trachomatis infection. This study was aimed to demonstrate the profound association of IL-10 with infertility and demonstrate the role of IL-10 (-592 C/A rs1800872) and (-1082 A>G rs1800896) single nucleotide polymorphism (SNPs) gene in the susceptibility and severity of a C. trachomatis infection.

Methods

In this evaluation study, serum IL-10 concentration was measured in 134 women diagnosed with infertility and 50 healthy volunteers by enzyme-linked immunosorbent assay (ELISA). The tetra-amplification refractory mutation system-PCR (T-ARMS-PCR) analysis was performed to detect the genotyping of the rs1800872 and rs1800896 SNPs genes.

Results

Both female groups were positive for anti-chlamydial IgM antibody, but the intensity of response differed between cases. At the same time, the incidence of genital C. trachomatis by PCR was 46.2% in infertile women. The serum concentration of IL10 was lower in infertile women than healthy participants and higher in infertile C. trachomatis -positive women compared to infertile C. trachomatis-negative in all groups except endometriosis (Endo) infertility. In rs1800872, the CA genotype and C allele are associated with an increased risk for infertility, except in polycystic ovarian syndrome (PCOS), which is an A allele. In the case of rs1800896, the AG genotype and G allele show a greater risk for infertility.

Conclusions

Our results confirmed that rs1800872 and rs1800896 gene polymorphisms were associated with an increased risk of C. trachomatis infection.

Toxocara Canis Increases the Potential of Breast Cancer by Reducing the Expression of the P53 Protein

INTRODUCTION

Breast cancer is considered the most frequent type of cancer in women with high mortality worldwide, and most importantly, it is the second most common cancer. However, some breast cancer-related risk factors remain unknown. So, the current study was designed to evaluate the effect of Toxocara canis on the biomarkers correlated with proliferation, apoptosis, inflammation, and angiogenesis in 4T1 tumor-bearing mice infected with Toxocara canis for the first time.

METHODS

Mice were categorized into four groups: A) control, B) treated with 4T1+ Toxocara canis, C) treated with Toxocara canis, and D) treated with 4T1. The expression of Ki-67 and P53 was then evaluated by using the immunohistochemical technique. In addition, the levels of transforming growth factor-β, Interferon gamma-γ, Interleukin 10, tumor necrosis factor-α and vascular endothelial growth factor as well as anti- Toxocara canis IgG were determined using the enzyme-linked immunosorbent assay method.

RESULTS

The expression of Ki-67 was significantly increased in the 4T1+ Toxocara canis group than control and Toxocara canis groups (P < 0.001 and P < 0.001, respectively). Moreover, a significant decrease in P53 was found in the 4T1+ Toxocara canis group than in the control and Toxocara canis groups (P < 0.001 and P < 0.001, respectively). Also, the 4T1+ Toxocara canis group significantly reduced the expression of P53 more than 4T1 tumor-bearing mice (P = 0.005). In addition, the 4T1+ Toxocara canis group had an increasing tumor necrosis factor-α and vascular endothelial growth factor than controls (P = 0.004 and P = 0.002, respectively). Furthermore, a significant reduction in Interleukin 10 was found in the 4T1+ Toxocara canis group than in the control group (P = 0.004).

CONCLUSION

Our findings showed that Toxocara canis could probably increase the potential of breast cancer by reducing P53 in 4T1 tumor-bearing mice infected with Toxocara canis more than other groups.

Prevalence of human papilloma virus and Chlamydia trachomatis in endometrial and cervical carcinoma: a comparative study in North Indian women

Cervical cancer (Cacx) is the second and endometrial cancer (Ec) is the third most common gynecological cancer worldwide. The present study aims to understand the complex and unexplored conditions occurring in cervix and endometrium of the female genital tract caused due to the infection of the human papilloma viruses (HPVs) and Chlamydia trachomatis (CT). A total of 300 tissue biopsy samples of cervix and endometrium were included in the present study and tested for the presence of HPV and CT deoxyribonucleic acid (DNA) by using polymerase chain reaction (PCR) technique. The odds ratios and 95% confidence interval were considered for the calculation of the association of HPV and CT infection with the risk of cervical or Ec. Among endometrial patients, samples were 5% positive for HPV and 5% positive for CT infection. Among endometrial control group, no sample was found positive for either HPV or CT infection. Among cervical patients, 72% samples were positive for only HPV infection and 1% samples were positive for only CT infection. Among control group, 7% of samples were positive for only HPV infection and 3% were positive for only CT infection. The co-infection of CT with HPV in 9% of Cacx cases and in 2% of cervical control samples was also observed. This is the first study in Indian women to detect the prevalence of HPV and CT infections in endometrium cases and control. An updated estimate regarding the HPV and CT prevalence in cervix cases and control samples was also provided.