166. MATERNAL OBESITY IS ASSOCIATED WITH AN INCREASED INCIDENCE OF PROSTATE ABNORMALITIES IN ADULT RAT OFFSPRING

Abstract

The World Health Organization has stated that 75% of adults worldwide are overweight, and in Australia nearly 25% of men are obese. Obesity is associated with an increased risk of cardiovascular disease, type 2 diabetes and cancer, with 30 to 40% of the latter possibly preventable by maintaining a healthy weight (The International Association for the Study of Obesity). Prostate cancer is the most commonly diagnosed cancer in men and there is increasing evidence that obesity increases the risk of prostate cancer mortality. High birth weight, an indication of excess nutrition during foetal development, has been associated with an increased risk of childhood and adult obesity, and for cancer. Using an animal model, we investigated whether obese mothers are more likely to have obese sons who are at an increased risk of developing prostate abnormalities and thus prostate cancer, in adulthood. Female rats were fed with either a control diet (4g fat/kg) or high fat diet (100g fat/kg) from before mating and throughout pregnancy. Prostate tissues were collected from the male offspring at 90 days (post-puberty) and 180 days (young adult). Histological analysis of the day 90 prostates identified hyperplasia in 100% of the ventral lobes (VL) and 64% of the dorsolateral lobes (DLP) in offspring of the maternal high fat group compared to 0% in each respectively, in those of the maternal control diet group. The VL is the most hormone sensitive prostate lobe of the rat, while the DLP is considered the equivalent of the human peripheral zone, the region from which the majority of human prostate cancers arise. These results suggest for the first time that maternal high fat diet may induce prostate abnormalities in male offspring that may in turn, predispose to an increased risk of prostate cancer in later life.