Predicting Tumour Progression of ID-8 Syngeneic Mouse Ovarian Cancer with Blood Biomarkers of CA-125, IL-6 and VEGF: A Prospective Laboratory-Based Study

Background: A preclinical animal model is an imperative tool for uncovering and understanding the tumourigenic hallmarks of human ovarian cancer; the disease is often lethal because it is commonly diagnosed in the advanced stage, where widespread cancer nodules mainly reside within peritoneal regions. Mouse models as a xenograft tumour host or genetic manipulation ovarian cancer-derived mice are widely used for studying specific hypothesis rationale in ovarian cancer. However, limited information associated with disease progression is obtained from such studies; whether it is the best model to study advanced ovarian cancer phenotype or suitable preclinical biomarkers for detecting and monitoring ovarian cancer progression is under study. This study used an ID-8 syngeneic mouse ovarian cancer model with immunocompetence. We monitored cancer growth and development using combination modalities of cancer-specific cancer antigen-125 (CA-125), interleukin-6 (IL-6) and vascular endothelial growth factor (VEGF) blood markers, which are well-known for their association with tumour progression in humans. Methods: Ten C57/BL6 female mice were intraperitoneally implanted with ID-8 Trp53 wild-type and monitored the progression of the tumour, until mice developed clinical ascites. Blood was taken at the time of intraperitoneal (IP) implantation (Day 0) and then collected weekly, and levels of biomarkers were analysed with enzyme-linked immunosorbent assay (ELISA). In addition, tumour tissue was collected and proceeded with histological staining. Results: We found that blood biomarkers CA-125, IL-6 and VEGF were not readily correlated with tumour progression. However, these biomarkers were markedly elevated in ascitic fluid at the advanced stage of the disease. Conclusions: We conclude that blood biomarkers in a syngeneic mouse model are, to some extent, not readily found in the blood as opposed to human ovarian cancer. Model anatomical and physiological differences between rodents and humans might explain this discrepancy.