title: Progestins activate 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3) in breast cancer cells.
abstract: PFKFB (6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase) catalyses the synthesis and degradation of Fru-2,6-P2 (fructose-2,6-bisphosphate), a key modulator of glycolysis and gluconeogenesis. The PFKFB3 gene is extensively involved in cell proliferation owing to its key role in carbohydrate metabolism. In the present study we analyse its mechanism of regulation by progestins in breast cancer cells. We report that exposure of T47D cells to synthetic progestins (ORG2058 or norgestrel) leads to a rapid increase in Fru-2,6-P2 concentration. Our Western blot results are compatible with a short-term activation due to PFKFB3 isoenzyme phosphorylation and a long-term sustained action due to increased PFKFB3 protein levels. Transient transfection of T47D cells with deleted gene promoter constructs allowed us to identify a PRE (progesterone-response element) to which PR (progesterone receptor) binds and thus transactivates PFKFB3 gene transcription. PR expression in the PR-negative cell line MDA-MB-231 induces endogenous PFKFB3 expression in response to norgestrel. Direct binding of PR to the PRE box (-3490 nt) was confirmed by ChIP (chromatin immunoprecipiation) experiments. A dual mechanism affecting PFKFB3 protein and gene regulation operates in order to assure glycolysis in breast cancer cells. An immediate early response through the ERK (extracellular-signal-regulated kinase)/RSK (ribosomal S6 kinase) pathway leading to phosphorylation of PFKFB3 on Ser461 is followed by activation of mRNA transcription via cis-acting sequences on the PFKFB3 promoter.
authors: Departament de Ciències Fisiològiques II, IDIBELL (Institut d'Investigacró Biomèdica de Bellvitge), Campus de Bellvitge, Universitat de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain.
authors: Laura
authors: L
authors: Novellasdemunt
authors: Mercè
authors: M
authors: Obach
authors: Lluís
authors: L
authors: Millán-Ariño
authors: Anna
authors: A
authors: Manzano
authors: Francesc
authors: F
authors: Ventura
authors: Jose Luis
authors: JL
authors: Rosa
authors: Albert
authors: A
authors: Jordan
authors: Aurea
authors: A
authors: Navarro-Sabate
authors: Ramon
authors: R
authors: Bartrons
mesh_terms: D001483:Base Sequence; D001943:Breast Neoplasms / Q000235:genetics / Q000378:metabolism*; D045744:Cell Line, Tumor; D004789:Enzyme Activation / Q000187:drug effects; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006801:Humans; D020935:MAP Kinase Signaling System; D009644:Norgestrel / Q000494:pharmacology; D025481:Phosphofructokinase-2 / Q000235:genetics / Q000378:metabolism*; D011282:Pregnenediones / Q000494:pharmacology; D045167:Progesterone Congeners / Q000494:pharmacology*; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012334:RNA, Neoplasm / Q000235:genetics / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism
chemical_list: D011282:Pregnenediones; D045167:Progesterone Congeners; D012333:RNA, Messenger; D012334:RNA, Neoplasm; D011980:Receptors, Progesterone; C020175:16 alpha-ethyl-21-hydroxy-19-nor-4-pregnene-3,20-dione; D009644:Norgestrel; C107345:PFKFB3 protein, human; D025481:Phosphofructokinase-2