ABSTRACT
BACKGROUND/AIM: Patients with breast cancer and metabolic syndrome have poorer outcomes. We aimed to develop and characterise an apolipoprotein E-null/aromatase knockout (ApoE-/-/ArKO) mouse model of breast cancer with metabolic syndrome to aid research of the mechanisms behind poor prognosis. MATERIALS AND METHODS: Wild-type, ApoE-/- and ApoE-/-/ArKO mice were orthotopically implanted with EO771 murine breast cancer cells. Tumour growth was monitored and tumours investigated for pathological features such as cancer-associated adipocytes, hypoxia and cancer cell proliferation. RESULTS: Tumours from ApoE-/-/ArKO mice were significantly more proliferative than those from wild-type mice (p=0.003), and exhibited reduced expression of insulin-like growth factor binding protein-5 (p=0.002). However, ApoE-/-/ArKO mice also had a reduced rate of metastasis compared to wild-type and ApoE-/- mice. Tumour hypoxia and the number of cancer-associated adipocytes did not differ. CONCLUSION: The ApoE-/-/ArKO model with EO771 breast cancer provides a novel mouse model to investigate the effects of metabolic syndrome on aspects of breast tumour biology.
