Changes in the Expression of the Peroxisome Proliferator-Activated Receptor γ Gene in the Colonic Polyps and Colonic Mucosa of Acromegalic Patients

Acromegalic patients have an increased prevalence of colonic neoplasms and lower peroxisome proliferator-activated receptor γ (PPARγ) levels, the latter acting as a tumor suppressor gene. In this study we evaluated the expression of PPARγ in the biopsy samples of the polyps and outside polyps colonic mucosa from seven patients with active, untreated acromegaly, 11 with cured disease, and 15 controls. Serum GH and IGF-I levels were higher in patients with untreated acromegaly than in those with acromegaly in remission or controls (P = 0.003 and P = 0.002, respectively) The expression of PPARγ mRNA (mean ± se) was 1) mucosa outside polyps, 24,188 ± 3,254 transcripts in the controls, 22,432 ± 2,006 transcripts in acromegaly in remission, and 1,952 ± 342 transcripts in untreated acromegaly (P < 0.0001 vs. controls and acromegaly in remission); and 2) polyps mucosa, 1,554 ± 236 transcripts in the controls, 1,112 ± 143 in acromegaly in remission, and 1,570 ± 251 in untreated acromegaly (P = NS among polyps grou...