Periprostatic fat gene expression in male mouse diet induced obesity study

Obesity is associated with an increased incidence of high grade prostate cancer (PC) and worse prognosis for PC patients. Recently, we showed in men that obesity-related periprostatic white adipose tissue (WAT) inflammation, characterized by macrophages surrounding dead or dying adipocytes forming crown-like structures, was associated with high grade PC. Possibly, interventions that suppress periprostatic WAT inflammation will improve outcomes for men with PC. Prior to testing interventions we conducted this study to identify transcriptomic differences in periprostatic fat from lean and obese mice. We hypothesized that periprostatic fat from obese mice would have a proinflammatory signature in gene expression pattern. To test our hypothesis that obese mice would develop molecular signatures of inflammation in periprostatic fat, we fed mice low fat diet or high fat diet for 12 weeks and then harvested periprostatic fat at sacrifice. RNA was isolated and analyzed from 5 lean and 5 obese mice and analyzed by microarray. Male C57BL/6J mice were obtained from The Jackson Laboratory and fed low fat diet (10 kcal% fat, 12450Bi; Research Diets), n=4 or high fat diet (60 kcal% fat, D12492i), n=5 beginning at 6 weeks of age. The mice were continued on these diets for a total of 12 weeks before being sacrificed by CO2 asphyxiation at 18 weeks of age.