Characterisation of a Mouse Model of Breast Cancer with Metabolic Syndrome.

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, ApoEand 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 ApoEmice. 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.