title: Oncogenic H-Ras up-regulates acid β-hexosaminidase by a mechanism dependent on the autophagy regulator TFEB.
abstract: The expression of constitutively active H-RasV12 oncogene has been described to induce proliferative arrest and premature senescence in many cell models. There are a number of studies indicating an association between senescence and lysosomal enzyme alterations, e.g. lysosomal β-galactosidase is the most widely used biomarker to detect senescence in cultured cells and we previously reported that H-RasV12 up-regulates lysosomal glycohydrolases enzymatic activity in human fibroblasts. Here we investigated the molecular mechanisms underlying lysosomal glycohydrolase β-hexosaminidase up-regulation in human fibroblasts expressing the constitutively active H-RasV12. We demonstrated that H-Ras activation increases β-hexosaminidase expression and secretion by a Raf/extracellular signal-regulated protein kinase dependent pathway, through a mechanism that relies on the activity of the transcription factor EB (TFEB). Because of the pivotal role of TFEB in the regulation of lysosomal system biogenesis and function, our results suggest that this could be a general mechanism to enhance lysosomal enzymes activity during oncogene-induced senescence.
authors.affiliation: Department of Experimental Medicine and Biochemical Sciences, University of Perugia, Perugia, Italy.
authors.forename: Lorena
authors.initials: L
authors.lastname: Urbanelli
authors.affiliation: Department of Experimental Medicine and Biochemical Sciences, University of Perugia, Perugia, Italy ; Department of Medical and Biological Sciences (DSMB), University of Udine, Udine, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Magini
authors.affiliation: Department of Clinical Sciences, Section of Biochemistry, Biology and Physics, Marche Polytechnic University, Ancona, Italy.
authors.forename: Luisa
authors.initials: L
authors.lastname: Ercolani
authors.affiliation: Department of Experimental Medicine and Biochemical Sciences, University of Perugia, Perugia, Italy.
authors.forename: Krizia
authors.initials: K
authors.lastname: Sagini
authors.affiliation: Department of Experimental Medicine and Biochemical Sciences, University of Perugia, Perugia, Italy.
authors.forename: Alice
authors.initials: A
authors.lastname: Polchi
authors.affiliation: Department of Experimental Medicine and Biochemical Sciences, University of Perugia, Perugia, Italy.
authors.forename: Brunella
authors.initials: B
authors.lastname: Tancini
authors.affiliation: Department of Experimental Medicine and Biochemical Sciences, University of Perugia, Perugia, Italy ; Centro di Eccellenza sui Materiali Innovativi Nanostrutturati (CEMIN), University of Perugia, Perugia, Italy.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Brozzi
authors.affiliation: Department of Clinical Sciences, Section of Biochemistry, Biology and Physics, Marche Polytechnic University, Ancona, Italy.
authors.forename: Tatiana
authors.initials: T
authors.lastname: Armeni
authors.affiliation: Department of Clinical Sciences, Section of Biochemistry, Biology and Physics, Marche Polytechnic University, Ancona, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Principato
authors.affiliation: Department of Experimental Medicine and Biochemical Sciences, University of Perugia, Perugia, Italy ; Centro di Eccellenza sui Materiali Innovativi Nanostrutturati (CEMIN), University of Perugia, Perugia, Italy.
authors.forename: Carla
authors.initials: C
authors.lastname: Emiliani
mesh_terms: D001343:Autophagy; D051778:Basic Helix-Loop-Helix Leucine Zipper Transcription Factors / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D015153:Blotting, Western; D002478:Cells, Cultured; D016922:Cellular Senescence; D047369:Chromatin Immunoprecipitation; D020405:Dermis / Q000378:metabolism* / Q000473:pathology; D024202:Electrophoretic Mobility Shift Assay; D048049:Extracellular Signal-Regulated MAP Kinases / Q000235:genetics / Q000378:metabolism; D005347:Fibroblasts / Q000378:metabolism* / Q000473:pathology; D015971:Gene Expression Regulation, Enzymologic; D006801:Humans; D008156:Luciferases / Q000378:metabolism; D008247:Lysosomes / Q000201:enzymology; D009154:Mutation / Q000235:genetics; D016283:Proto-Oncogene Proteins p21(ras) / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics; D034741:RNA, Small Interfering / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015533:Transcriptional Activation; D015854:Up-Regulation; D001616:beta-Galactosidase / Q000378:metabolism; D001619:beta-N-Acetylhexosaminidases / Q000235:genetics* / Q000378:metabolism; D048490:raf Kinases / Q000235:genetics / Q000378:metabolism
chemical_list: D051778:Basic Helix-Loop-Helix Leucine Zipper Transcription Factors; D012333:RNA, Messenger; D034741:RNA, Small Interfering; C064972:TFEB protein, human; D008156:Luciferases; D048490:raf Kinases; D048049:Extracellular Signal-Regulated MAP Kinases; D001616:beta-Galactosidase; D001619:beta-N-Acetylhexosaminidases; C501009:HRAS protein, human; D016283:Proto-Oncogene Proteins p21(ras)