Abstract
BACKGROUND: Cancer is a leading cause of morbidity and mortality, with brain tumors posing significant challenges due to their site and complexity. Therefore, exploring tumor pathogenesis and the discovery of novel therapeutic agents have drawn attention to the role of infectious agents. Toxoplasma gondii is a highly prevalent protozoan parasite that establishes a chronic latent infection in neural tissues. Several epidemiological studies have linked infection with Toxoplasma gondii to a higher risk of developing cancer, particularly brain tumors. However, research findings are controversial, with some reports suggesting no clear link, and others even proposing that Toxoplasma gondii infection could ignite the immune system, consequently fighting brain cancer. MAIN BODY: In this review, we screened several major scientific databases for studies published up to July 2025. We included human and experimental studies that explored the potential oncogenic and oncosuppressive effects of Toxoplasma gondii in brain tumors. While some epidemiological studies suggest that Toxoplasma gondii infection is a risk factor, others have pointed out that the incidence of this parasitic infection may be due to the opportunistic nature of the parasite, leading to reactivation of latent infection or acquiring a new infection in immunosuppressed cancer patients. Additionally, pre-clinical studies have shown that Toxoplasma gondii could boost the immune cells and modify the tumor microenvironment to fight brain tumors. CONCLUSION: This review emphasizes the potential role of Toxoplasma gondii as a valuable resource that warrants further exploration for its promising anti-neoplastic activity against brain cancer, as well as other types of cancer.