Toxoplasma gondii: Seroprevalence and association with childhood brain tumors in Egypt

BACKGROUND

Childhood brain tumors are a significant global health challenge, yet the etiology of these tumors remains elusive. While research has identified potential risk factors, recent studies have explored the involvement of infectious agents, particularly Toxoplasma gondii (T. gondii), in brain tumor development.

METHODS

This study aimed to explore the prevalence of T. gondii infection in children diagnosed with brain tumors and to investigate the potential association between T. gondii infection and childhood brain tumors in Egypt. A total of 64 children with brain tumors and 92 healthy controls were enrolled in this study. Demographics and risk factors data were collected using structured questionnaires. Serological assay using ELISA technique was performed to detect anti-T. gondii antibodies in both cases and control groups.

RESULTS

This study revealed a significantly higher seroprevalence of T. gondii infection in brain tumor cases (62.5 %) compared to healthy controls (38 %). Furthermore, a strong association was observed between T. gondii seropositivity and childhood brain tumors (odds ratio: 2.7). Notably, the consumption of unwashed vegetables emerged as a significant risk factor for T. gondii infection in Egypt. Analysis of T. gondii seroprevalence across different subtypes of brain tumors revealed varying rates, with glioma cases displaying a striking 100 % seroprevalence.

CONCLUSIONS

These findings support the hypothesis that T. gondii infection may be a risk factor for childhood brain tumors and emphasize the need for further research in this area. The study also highlights the potential implications of control of T. gondii infection for prevention and treatment of childhood brain tumors.

Toxoplasma gondii infection in patients with brain tumors in Southern Iran: a case-control study

Considerable evidence points to a dominant role of inflammation in tumor pathology. The biological response of the immune system can be triggered by Toxoplasma gondii as a common brain-tropic parasite. The aim of this study was to investigate an association between Toxoplasma infection and brain tumors. This case-control study was performed on sera of brain tumor patients (n = 124) and age- and sex-matched control subjects (n = 124) in Southern Iran. Data related to tumor site and type were collected during sample collection. Anti-Toxoplasma IgG was assessed by enzyme-linked immunosorbent assay (ELISA). Seroprevalence anti-Toxoplasma IgG was significantly higher in brain tumor patients 30.6% (38/124) compared with 12.1% (15/124) of the healthy controls (OR 3.211; 95% CI 1.658 to 6.219; p = 0.001). The highest seroprevalence was detected in patients with ependymoma (100%), followed by glioblastoma (83%), pituitary adenoma (47.3%), astrocytoma (27.2%), schwannoma (23%), and meningioma (22.6%). The parasite infection was correlated to brain tumor's location i.e., the patients with frontal lobe and sella region tumors had higher seropositivity compared with others (P < 0.05). The higher prevalence of Toxoplasma infection among patients with brain tumor compared with the control group indicates a probable association between the infection and brain tumors.

Shedding light on a mysterious link between Toxoplasma Gondii and cancer: A review

The ongoing conflict regarding the affiliation of Toxoplasma gondii to cancer; whether an inducer or a suppressor needs to be resolved. Human epidemiological studies oscillate without attaining a firm ground. Some studies confirmed the detection of high seroprevalence of anti-Toxoplasma antibodies in different cancer patients without further justification whether being causation, co-incidences, or part of opportunistic infections. Others reported a state of resistance to cancer accompanying low titer of anti-Toxoplasma antibody. Worthwhile, preclinical experimental work confirmed the antineoplastic potency of Toxoplasma. Thus, further investigational research is essential to validate the potential application of Toxoplasma as a promising cancer immunotherapeutic vaccine candidate. In this paper, we present a review of this issue by examining epidemiological and preclinical experimental studies that explored the linkage between Toxoplasma gondii and cancer<i.></i> We consider this review an important step towards shedding a light on this mysterious link and a stepping-stone for potential research work addressing Toxoplasma as a cancer suppressor rather than a cancer inducer.

Differentiating Cerebral Toxoplasmosis and Tumor Recurrence by Thallium-201 Single-Photon Emission Computerized Tomography in a 28-Year-Old Female with Astrocytoma

Cerebral toxoplasmosis is an opportunistic infection that, by itself, is difficult to differentiate from cerebral neoplasms by conventional neuroimaging. It rarely occurs concurrently in patients with a primary brain tumor but when it does, it makes diagnosis and management more difficult. This is a case of a 28-year-old female, diagnosed with a right frontal pleomorphic xanthoastrocytoma with several recurrences, treated with surgery, radiation, and chemotherapy. Three years from diagnosis, the patient was readmitted for generalized body weakness, fever, and a decrease in sensorium. A repeat cranial magnetic resonance imaging showed multiple enhancing lesions in both cerebral hemispheres and in the posterior fossa. Serum toxoplasma IgM and IgG antibody titers were elevated. Single-photon emission computerized tomography (SPECT) with thallium-201 did not show increased tracer uptake in these lesions, favoring toxoplasmosis over tumor recurrence. The patient was treated with trimethoprim-sulfamethoxazole with significant improvement. This is a rare account of cerebral toxoplasmosis arising in the setting of astrocytoma. This is also the first case report to demonstrate the value of thallium-201 SPECT in differentiating central nervous system infection from tumor recurrence, which is pivotal in management. More studies exploring the use of thallium-201 SPECT in distinguishing central nervous system infections from glioma and other malignant tumors should be undertaken to maximize this imaging modality in neuro-oncology practice.

Endothelial Cells Potentially Participate in the Metastasis of Triple-Negative Breast Cancer

Inhibition of triple-negative breast cancer metastasis has long been a challenge, mainly due to the difficulty in identifying factors that contribute to this process. In this study, freshly isolated triple-negative breast cancer biopsied cells obtained from consenting patients were subjected to flow cytometry and bioinformatic analysis to identify three endothelial cell subclusters: EC (ATP1B3), EC (HSPA1B), and EC (KRT7) in the tumor microenvironment. These endothelial cell subclusters exhibited distinguishing biological features. Based on differentially expressed genes derived from the subclusters, gene set enrichment analysis showed that EC (ATP1B3) and EC (HSPA1B) contribute to the process of metastasis, for example, in fibrosarcoma and anaplastic carcinoma. In this study, we identified the heterogeneity of endothelial cells in the human breast cancer and have provided insights into its role in metastasis.

Association between Toxoplasma gondii exposure and hematological malignancies: A systematic review and meta-analysis

The possible association between Toxoplasma gondii infection and hematological malignancies has been suggested by several studies. The current systematic review and meta-analysis was directed to further understand this relationship. In the present study, five electronic databases were reviewed for T. gondii infection in patients with blood cancer. The random effects model and 95% confidence intervals (CI) were used to determine the overall odds ratio (OR). Heterogeneity was deliberate with Cochran's Q test and I² statistic. In total, 13 studies including 1504 patients with hematological neoplasia and 2622 subjects without any malignancies were included in this meta-analysis. Overall, 324 patients with blood cancer and 391 subjects without any malignancies were exposed to Toxoplasma infection. The pooled random effect favored a statistically significant increased risk of T. gondii infection in patients with hematological neoplasia compared with non-cancer individuals [OR = 2.43; 95% CI: 1.49-3.97; χ2 = 49.7, I² = 75.9%, P = 0.00]. Also, significant pooled ORs of positive association were observed for studies which measured anti- Toxoplasma antibodies (IgG) [OR = 2.66; 95% CI: 1.46-4.83; χ2 = 40.3; I² = 82.6%, P = 0.00]. T-value and P-value were obtained 0.20 and 0.85 by Harbords modified regression test. This meta-analysis demonstrates that toxoplasmosis may be associated with an elevated risk of hematological malignancies. Also, it has found that immunoglobulin class and types of blood cancer are the specific sources of heterogeneity. Additional studies should be performed to examine the impact of T. gondii infection in the onset or development of hematologic neoplasms in the future.

Toxoplasma gondii in cancer patients receiving chemotherapy: seroprevalence and interferon gamma level

Toxoplasma gondii is an opportunistic parasite causing life-threatening diseases in immune-compromised patients. The purpose of the study is to determine the seroprevalence of Toxoplasma gondii in chemotherapy receiving cancer patients in relation to different types of malignancies, and to estimate the level of interferon gamma in Toxoplasma seropositive and seronegative cancer patients and healthy controls. Anti-Toxoplasma IgG and IgM antibodies, and interferon gamma were analyzed in 120 cancer patients receiving chemotherapy (60 having hematological malignancies and 60 with solid organ tumors) and 60 healthy controls using ELISA method. Toxoplasma (IgG and IgM) were determined in (66.7% and 9.2%) of the cancer group compared to (33.3% and 6.7%) of the control group with statistical significance only in IgG seropositivity (p < 0.001, OR = 4). Patients with hematological malignancies had higher IgG seropositivity than solid organ tumors (40% vs 26.7%). The difference between the groups was statistically significant (p = 0.002, OR = 3.5). Median level of interferon gamma was in the same range between cancer patients and control group. However, it was highly elevated in Toxoplasma seropositive (76 pg/ml) than seronegative (44.5 pg/ml) cases with statistical significance (p < 0.001). T. gondii infection remains a major threat to cancer patients and still needs proper screening, diagnosis and treatment.

Seroprevalence of Toxoplasma gondii infection in cancer patients: A systematic review and meta-analysis

Toxoplasmosis, caused by Toxoplasma gondii, is a great public health concern in cancer patients, which can induce serious pathological effects. This systematic review and meta-analysis was performed to evaluate the worldwide seroprevalence rate of T. gondii infection among cancer patients. A search was conducted on five electronic databases that reported data on T. gondii seroprevalence in cancer patients. The searching process resulted in the inclusion of 57 studies. The results showed that T. gondii had the pooled prevalence of 30.8% in cancer patients using a random-effect model (95% CI: 26.3-35.6). Cancer patients had a higher overall prevalence of T. gondii infection, compared to those without cancer. Furthermore, the odds ratio of toxoplasmosis in cancer patients was 3.1 times, compared to that of controls (95% CI: 2.5-3.8, P < 0.0001). Toxoplasmosis had a higher prevalence in females (40%) than in males (33%). Furthermore, the age group of upper 40 years had the highest prevalence infection rate (30%). In addition, a significant association was also observed between toxoplasmosis infection and year (P < 0.001), type of cancer (P < 0.001), country (P < 0.001), gender (P < 0.001), age (P = 0.006) and diagnostic method (P < 0.001) in cancer patients. Considering the high prevalence of T. gondii infection in cancer patients and its serious outcomes, the researchers are suggested to carry out further studies to prevent and control toxoplasmosis among this population.