Obesity increases tumor aggressiveness in a genetically engineered mouse model of serous ovarian cancer

• Obesity promotes tumor progression in the KpB mouse model of serous ovarian cancer.
• Gene expression and metabolomic profiling indicated significant differences between ovarian tumors from obese versus non-obese mice, including metabolically relevant pathways.

ObjectivesObesity is associated with increased risk and worse outcomes for ovarian cancer. Thus, we examined the effects of obesity on ovarian cancer progression in a genetically engineered mouse model of serous ovarian cancer.MethodsWe utilized a unique serous ovarian cancer mouse model that specifically deletes the tumor suppressor genes, Brca1 and p53, and inactivates the retinoblastoma (Rb) proteins in adult ovarian surface epithelial cells, via injection of an adenoviral vector expressing Cre (AdCre) into the ovarian bursa cavity of adult female mice (KpB mouse model). KpB mice were subjected to a 60% calories-derived from fat in a high fat diet (HFD) versus 10% calories from fat in a low fat diet (LFD) to mimic diet-induced obesity. Tumors were isolated at 6 months after AdCre injection and evaluated histologically. Untargeted metabolomic and gene expression profiling was performed to assess differences in the ovarian tumors from obese versus non-obese KpB mice.ResultsAt sacrifice, mice on the HFD (obese) were twice the weight of mice on the LFD (non-obese) (51 g versus 31 g, p = 0.0003). Ovarian tumors were significantly larger in the obese versus non-obese mice (3.7 cm2 versus 1.2 cm2, p = 0.0065). Gene expression and metabolomic profiling indicated statistically significant differences between the ovarian tumors from the obese versus non-obese mice, including metabolically relevant pathways.