Objective:

To evaluate the mechanistic pathways underlying both pro-tumour and anti-tumour effects of parasites or parasite-derived products across different experimental models and to identify shared versus tumour-specific biological patterns across cancer types.

Approach:

• Systematic Review: A total of 34 studies were reviewed, focusing on whole parasites and parasite-derived molecules, including vesicles, peptides, proteins, and miRNAs, across various cancer types.
• Literature Search: The search was conducted using PubMed/MEDLINE, EMBASE, and the Cochrane Library, employing specific keywords related to parasites and cancer outcomes.
• Eligibility Criteria: Included studies investigated the direct effects of parasites or their molecules on cancer initiation, progression, or regression using in vitro or in vivo models.

Key Findings:

• Pro-tumour effects are linked to chronic inflammation, oxidative stress, epithelial proliferation, and immune modulation.
• Anti-tumour effects are associated with direct cytotoxicity, inhibition of migration, and immune activation.
• Certain parasite-derived molecules exhibit anti-tumour effects beyond their usual sites of infection.

Interpretation:

The review discusses the dual influence of parasites and their products on cancer progression, indicating both potential cancer-promoting factors and anticancer therapeutic candidates.

Limitations:

• Limited studies have investigated direct interactions between secretory molecules and cancer cells.
• Existing studies are scattered across individual experimental models, lacking comprehensive understanding of common mechanistic pathways.

Conclusion:

Further mechanistic and translational studies are necessary to explore the roles of parasites and their products in cancer biology.

Sources:

• Systematic Review Registration