Diet-induced alteration of fatty acid synthase in prostate cancer progression.

Fatty acid synthase (FASN) is a cytosolic metabolic enzyme that catalyzes de novo fatty acid synthesis. A high-fat diet (HFD) is attributed to prostate cancer (PCa) progression, but the role FASN on HFD-mediated PCa progression remains unclear.

We investigated the role of FASN on PCa progression in LNCaP xenograft mice fed with HFD or low-fat diet (LFD), in PCa cells, and in clinical PCa. The HFD promoted tumour growth and FASN expression in the LNCaP xenograft mice. HFD resulted in AKT and extracellular signal-regulated kinase (ERK) activation and 5' adenosine monophosphate-activated protein kinase (AMPK) inactivation. Serum FASN levels were significantly lower in the HFD group (P=0. 026) and correlated inversely with tumour volume (P=0. 022). Extracellular FASN release was enhanced in the PCa cells with phosphatidylinositol 3-kinase (PI3K)/mitogen-activated protein kinase (MAPK) inhibition and AMPK signalling activation. FASN inhibition resulted in decrease of PCa cell proliferation through PI3K/MAPK downregulation and AMPK activation. Furthermore, AMPK activation was associated with FASN downregulation and PI3K/MAPK inactivation. Clinically, high FASN expression was significantly associated with high Gleason scores and advanced pathological T stage. Moreover, FASN expression was markedly decreased in the PCa response to androgen deprivation therapy and chemotherapy. HFD modulates FASN expression, which may be an important mechanism in HFD-associated PCa progression. Furthermore, a critical stimulatory loop exists between FASN and the PI3K/MAPK system, whereas AMPK signalling was associated with suppression. These may offer appropriate targets for chemoprevention and cancer therapy in HFD-induced PCa.

Oncogenesis. 2016 Feb 15*** epublish ***

M Huang, A Koizumi, S Narita, T Inoue, N Tsuchiya, H Nakanishi, K Numakura, H Tsuruta, M Saito, S Satoh, H Nanjo, T Sasaki, T Habuchi

Department of Urology, Akita University Graduate School of Medicine, Akita, Japan. , Department of Urology, Akita University Graduate School of Medicine, Akita, Japan. , Department of Urology, Akita University Graduate School of Medicine, Akita, Japan. , Department of Urology, Akita University Graduate School of Medicine, Akita, Japan. , Department of Urology, Akita University Graduate School of Medicine, Akita, Japan. , Research Center for Biosignal,Akita University Graduate School of Medicine, Akita, Japan. , Department of Urology, Akita University Graduate School of Medicine, Akita, Japan. , Department of Urology, Akita University Graduate School of Medicine, Akita, Japan. , Department of Urology, Akita University Graduate School of Medicine, Akita, Japan. , Department of Urology, Akita University Graduate School of Medicine, Akita, Japan. , Department of Clinical Pathology, Akita University Graduate School of Medicine, Akita, Japan. , AMED-CREST, Japan Agency for Medical Research and Development (AMED), Tokyo, Japan. , Department of Urology, Akita University Graduate School of Medicine, Akita, Japan.

PubMed