title: Depletion of the novel p53-target gene carnitine palmitoyltransferase 1C delays tumor growth in the neurofibromatosis type I tumor model.
abstract: Despite the prominent pro-apoptotic role of p53, this protein has also been shown to promote cell survival in response to metabolic stress. However, the specific mechanism by which p53 protects cells from metabolic stress-induced death is unknown. Earlier we reported that carnitine palmitoyltransferase 1C (CPT1C), a brain-specific member of a family of mitochondria-associated enzymes that have a central role in fatty acid metabolism promotes cell survival and tumor growth. Unlike other members of the CPT family, the subcellular localization of CPT1C and its cellular function remains elusive. Here, we report that CPT1C is a novel p53-target gene with a bona fide p53-responsive element within the first intron. CPT1C is upregulated in vitro and in vivo in a p53-dependent manner. Interestingly, expression of CPT1C is induced by metabolic stress factors such as hypoxia and glucose deprivation in a p53 and AMP activated kinase-dependent manner. Furthermore, in a murine tumor model, depletion of Cpt1c leads to delayed tumor development and a striking increase in survival. Taken together, our results indicate that p53 protects cells from metabolic stress via induction of CPT1C and that CPT1C may have a crucial role in carcinogenesis. CPT1C may therefore represent an exciting new therapeutic target for the treatment of hypoxic and otherwise treatment-resistant tumors.
authors: Laboratory for Applied Radiation Oncology, Department of Radiation Oncology, University Hospital, Zurich, Switzerland.
authors: N
authors: N
authors: Sanchez-Macedo
authors: J
authors: J
authors: Feng
authors: B
authors: B
authors: Faubert
authors: N
authors: N
authors: Chang
authors: A
authors: A
authors: Elia
authors: E J
authors: EJ
authors: Rushing
authors: K
authors: K
authors: Tsuchihara
authors: D
authors: D
authors: Bungard
authors: S L
authors: SL
authors: Berger
authors: R G
authors: RG
authors: Jones
authors: T W
authors: TW
authors: Mak
authors: K
authors: K
authors: Zaugg
mesh_terms: D055372:AMP-Activated Protein Kinases / Q000235:genetics / Q000378:metabolism; D000818:Animals; D001921:Brain / Q000201:enzymology; D002334:Carnitine O-Palmitoyltransferase / Q000235:genetics / Q000378:metabolism*; D015687:Cell Hypoxia; D002460:Cell Line; D049109:Cell Proliferation; D004195:Disease Models, Animal; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008928:Mitochondria / Q000378:metabolism; D009456:Neurofibromatosis 1 / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D025542:Neurofibromin 1 / Q000172:deficiency / Q000235:genetics / Q000378:metabolism; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000378:metabolism; D014158:Transcription, Genetic; D016159:Tumor Suppressor Protein p53 / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D015854:Up-Regulation
chemical_list: D025542:Neurofibromin 1; D012333:RNA, Messenger; D016159:Tumor Suppressor Protein p53; C558401:CPT1B protein, mouse; D002334:Carnitine O-Palmitoyltransferase; C548179:Prkaa1 protein, mouse; D055372:AMP-Activated Protein Kinases