title: Dedifferentiation of cancer cells following recovery from a potentially lethal damage is mediated by H2S-Nampt.
abstract: Recently, we reported that cancer cells that recover from a potentially lethal damage gain new phenotypic features comprised of mitochondrial structural remodeling associated with increased glycolytic dependency and drug resistance. Here, we demonstrate that a subset of cancer cells, upon recovery from a potentially lethal damage, undergo dedifferentiation and express genes, which are characteristic of undifferentiated stem cells. While these cells are competent in maintaining differentiated progeny of tumor, they also exhibit transdifferentiation potential. Dedifferentiation is characterized by accumulation of hydrogen sulfide (H2S), which triggers up-regulation of nicotinamide phosphoribosyltransferase (Nampt) accompanied by changes in the redox state. The molecular events triggered by Nampt include elevated production of NAD(+) and up-regulation of H2S producing enzymes, cystathionine beta synthase (CBS) and cystathionase (CTH) with 3-mercaptopyruvate sulfurtransferase (MST) being detectable only in 3D spheroids. Suppression of Nampt, or inactivation of H2S producing enzymes, all reduce H2S production and reverse the ability of cells to dedifferentiate. Moreover, H2S induced stem cell markers in parental cancer cells in a manner similar to that observed in damage recovered cells. These data suggest of existence of a positive feedback loop between H2S and Nampt that controls dedifferentiation in cancer cells that recover from a potentially lethal damage.
authors.affiliation: Frontiers in Bioscience Research Institute in Aging and Cancer, Irvine, CA 92618, USA.
authors.forename: Elena A
authors.initials: EA
authors.lastname: Ostrakhovitch
authors.affiliation: Frontiers in Bioscience Research Institute in Aging and Cancer, Irvine, CA 92618, USA.
authors.forename: Shin
authors.initials: S
authors.lastname: Akakura
authors.affiliation: Frontiers in Bioscience Research Institute in Aging and Cancer, Irvine, CA 92618, USA.
authors.forename: Reiko
authors.initials: R
authors.lastname: Sanokawa-Akakura
authors.affiliation: Department of Radiological Sciences, University of California, Irvine, CA 92868, USA.
authors.forename: Scott
authors.initials: S
authors.lastname: Goodwin
authors.affiliation: Frontiers in Bioscience Research Institute in Aging and Cancer, Irvine, CA 92618, USA; Department of Radiological Sciences, University of California, Irvine, CA 92868, USA. Electronic address: fbs@bioscience.org.
authors.forename: Siamak
authors.initials: S
authors.lastname: Tabibzadeh
mesh_terms: D000818:Animals; D054337:Cell Dedifferentiation; D054338:Cell Transdifferentiation; D003541:Cystathionine beta-Synthase / Q000378:metabolism; D003542:Cystathionine gamma-Lyase / Q000378:metabolism; D025461:Feedback, Physiological; D056945:Hep G2 Cells; D006801:Humans; D006862:Hydrogen Sulfide / Q000378:metabolism*; D051379:Mice; D014411:Neoplastic Stem Cells / Q000378:metabolism* / Q000502:physiology; D054409:Nicotinamide Phosphoribosyltransferase / Q000378:metabolism*; D013466:Sulfurtransferases / Q000378:metabolism
chemical_list: D054409:Nicotinamide Phosphoribosyltransferase; D013466:Sulfurtransferases; C021550:3-mercaptopyruvate sulphurtransferase; D003541:Cystathionine beta-Synthase; D003542:Cystathionine gamma-Lyase; D006862:Hydrogen Sulfide
keywords: Cancer cells; Dedifferentiation; Hydrogen sulfide; Nampt; Potentially lethal damage recovery