MBTPS2 acts as a regulator of lipogenesis and cholesterol synthesis through SREBP signalling in prostate cancer

BACKGROUND: Prostate cancer is the most common cancer in men in the developed world, with most deaths caused by advanced and metastatic disease which has no curative options. Here, we identified Mbtps2 alteration to be associated with metastatic disease in an unbiased in vivo screen and demonstrated its regulation of fatty acid and cholesterol metabolism. METHODS: The Sleeping Beauty transposon system was used to randomly alter gene expression in the Pten(Null) murine prostate. MBTPS2 was knocked down by siRNA in LNCaP, DU145 and PC3 cell lines, which were then phenotypically investigated. RNA-Seq was performed on LNCaP cells lacking MBTPS2, and pathways validated by qPCR. Cholesterol metabolism was investigated by Filipin III staining. RESULTS: Mbtps2 was identified in our transposon-mediated in vivo screen to be associated with metastatic prostate cancer. Silencing of MBTPS2 expression in LNCaP, DU145 and PC3 human prostate cancer cells reduced proliferation and colony forming growth in vitro. Knockdown of MBTPS2 expression in LNCaP cells impaired cholesterol synthesis and uptake along with reduced expression of key regulators of fatty acid synthesis, namely FASN and ACACA. CONCLUSION: MBTPS2 is implicated in progressive prostate cancer and may mechanistically involve its effects on fatty acid and cholesterol metabolism.