New Insights on Parasitic Infections and Cervical Cancer Risk

Recent research has unveiled a connection between the parasitic infection Schistosoma haematobium and the activation of cancer-related genes in the cervical lining. Findings presented at the ESCMID Global 2025 conference indicate that these genetic alterations can become more pronounced following treatment for the infection, shedding light on the potential role of this neglected disease in increasing the risk of cervical cancer at a molecular level.

Schistosomiasis, particularly prevalent in areas with inadequate access to clean water, affects millions worldwide. S. haematobium is one of the primary species responsible for human schistosomiasis, infecting over 110 million people by depositing eggs that infiltrate various bodily tracts. While the parasite is known to cause bladder cancer, its implications for cervical cancer had not been thoroughly investigated until now.

The study involved the analysis of cervical tissue samples from 39 Tanzanian women, with 20 infected by S. haematobium and 19 uninfected. The infected participants were treated with praziquantel, and samples were collected prior to and four to twelve months after treatment. Researchers employed RNA sequencing and gene expression analysis to identify cancer-related pathways associated with the infection.

Among the findings, nine genes exhibited differing expression levels between the infected and uninfected women. Furthermore, post-treatment analysis revealed that 23 genes changed in women who successfully cleared the infection, while 29 genes showed variation between women who had been treated and those who had never been infected.

Notably, four of the nine most significantly altered genes were linked to cancer:

• BLK proto-oncogene: This gene, a tyrosine kinase, is known to drive cell proliferation and can contribute to tumor formation when dysregulated.
• Long intergenic non-protein coding RNA 2084: Identified as a prognostic marker in multiple cancers, this gene influences regulatory mechanisms tied to tumor progression.
• Trichohyalin: This gene is involved in the formation of keratin complexes and is upregulated in certain cancer types.
• TCL1 family AKT coactivator A: This gene promotes cell survival and proliferation, linking it to T- and B-cell lymphomas.

Post-treatment results indicated that specific cancer-related biological pathways became more active. These pathways were associated with inflammation, tissue remodeling, and the breakdown of protective barriers within the cervix, leading to increased blood vessel formation, activation of tumor-promoting processes, and a decrease in programmed cell death (apoptosis)--a crucial mechanism for eliminating abnormal cells.

The research suggests that S. haematobium infection may initiate molecular changes that heighten women's susceptibility to cancer-related processes in the cervix, especially following treatment. One concerning finding was the downregulation of genes responsible for maintaining cervical tissue integrity, which could increase the risk of persistent HPV infection, a significant risk factor for cervical cancer.

The study raises important questions regarding the long-term effects of treatment and emphasizes the necessity of vigilant post-treatment monitoring. Furthermore, researchers are conducting a larger study involving 180 women over 12 months to validate these findings and explore whether prior schistosomiasis increases the risk of cervical cancer due to sustained HPV infections.

Researchers advocate for enhanced awareness regarding Female Genital Schistosomiasis (FGS), a condition that often accompanies S. haematobium infection and is challenging to diagnose. They recommend that women diagnosed with S. haematobium be monitored closely for early signs of cervical tissue abnormalities. Additionally, they propose that supplementary treatments, such as anti-inflammatory or immune-modulating therapies, may help mitigate the adverse effects observed post-treatment. Widespread HPV vaccination is also highlighted as a vital strategy to reduce cervical cancer risk in women affected by schistosomiasis.