Insulin-Like growth factor 1 related pathways and high-fat diet promotion of transgenic adenocarcinoma mouse prostate (TRAMP) cancer progression

Introduction: We aimed to investigate the role of IGF-1 related pathway in high-fat diet (HFD) promotion of TRAMP mouse PCa progression. Methods: TRAMP mice were randomly divided into two groups: HFD group and normal diet group. TRAMP mice of both groups were sacrificed and sampled on the 20th, 24th and 28th week respectively. Serum levels of insulin, IGF-1 and IGF-2 were tested by ELISA. Prostate tissue of TRAMP mice was used for both HE staining and immunohistochemical staining of IGF-1 related pathway proteins, including IGF-1R alpha, IGF -1R beta, IGFBPs and AKT. Results: The mortality of TRAMP mice from HFD group was significantly higher than that of normal diet group (23.81% and 7.14%, p=.035). The tumor incidence of HFD TRAMP mice at 20th week was significantly higher than normal diet group (78.57% and 35.71%, p=.022). Serum IGF-1 level of HFD TRAMP mice was significantly higher than that of normal diet TRAMP mice. Serum IGF-1 level tended to increase with HFD TRAMP mice's age. HFD TRAMP mice had higher positive staining rate of IGF-1R alpha, IGF-1R beta, IGFBP3 and Akt than normal diet TRAMP mice. Conclusions: IGF-1 related pathway played an important role in high-fat diet promotion of TRAMP mouse PCa development and progression. (C) 2014 AEU. Published by Elsevier Espana, S.L.U. All rights reserved.