title: Pyruvate carboxylase is critical for non-small-cell lung cancer proliferation.
abstract: Anabolic biosynthesis requires precursors supplied by the Krebs cycle, which in turn requires anaplerosis to replenish precursor intermediates. The major anaplerotic sources are pyruvate and glutamine, which require the activity of pyruvate carboxylase (PC) and glutaminase 1 (GLS1), respectively. Due to their rapid proliferation, cancer cells have increased anabolic and energy demands; however, different cancer cell types exhibit differential requirements for PC- and GLS-mediated pathways for anaplerosis and cell proliferation. Here, we infused patients with early-stage non-small-cell lung cancer (NSCLC) with uniformly 13C-labeled glucose before tissue resection and determined that the cancerous tissues in these patients had enhanced PC activity. Freshly resected paired lung tissue slices cultured in 13C6-glucose or 13C5,15N2-glutamine tracers confirmed selective activation of PC over GLS in NSCLC. Compared with noncancerous tissues, PC expression was greatly enhanced in cancerous tissues, whereas GLS1 expression showed no trend. Moreover, immunohistochemical analysis of paired lung tissues showed PC overexpression in cancer cells rather than in stromal cells of tumor tissues. PC knockdown induced multinucleation, decreased cell proliferation and colony formation in human NSCLC cells, and reduced tumor growth in a mouse xenograft model. Growth inhibition was accompanied by perturbed Krebs cycle activity, inhibition of lipid and nucleotide biosynthesis, and altered glutathione homeostasis. These findings indicate that PC-mediated anaplerosis in early-stage NSCLC is required for tumor survival and proliferation.
authors.forename: Katherine
authors.initials: K
authors.lastname: Sellers
authors.forename: Matthew P
authors.initials: MP
authors.lastname: Fox
authors.forename: Michael
authors.initials: M
authors.lastname: Bousamra
authors.forename: Stephen P
authors.initials: SP
authors.lastname: Slone
authors.forename: Richard M
authors.initials: RM
authors.lastname: Higashi
authors.forename: Donald M
authors.initials: DM
authors.lastname: Miller
authors.forename: Yali
authors.initials: Y
authors.lastname: Wang
authors.forename: Jun
authors.initials: J
authors.lastname: Yan
authors.forename: Mariia O
authors.initials: MO
authors.lastname: Yuneva
authors.forename: Rahul
authors.initials: R
authors.lastname: Deshpande
authors.forename: Andrew N
authors.initials: AN
authors.lastname: Lane
authors.forename: Teresa W-M
authors.initials: TW
authors.lastname: Fan
mesh_terms: D000818:Animals; D002289:Carcinoma, Non-Small-Cell Lung / Q000201:enzymology* / Q000235:genetics / Q000473:pathology; D049109:Cell Proliferation; D002952:Citric Acid Cycle / Q000235:genetics; D005260:Female; D015971:Gene Expression Regulation, Enzymologic; D015972:Gene Expression Regulation, Neoplastic; D005947:Glucose / Q000378:metabolism; D005978:Glutathione / Q000096:biosynthesis / Q000235:genetics; D057809:HEK293 Cells; D006801:Humans; D050356:Lipid Metabolism / Q000235:genetics; D008175:Lung Neoplasms / Q000201:enzymology* / Q000235:genetics / Q000473:pathology; D008297:Male; D051379:Mice; D009363:Neoplasm Proteins / Q000096:biosynthesis* / Q000235:genetics; D009711:Nucleotides / Q000096:biosynthesis / Q000235:genetics; D011766:Pyruvate Carboxylase / Q000096:biosynthesis* / Q000235:genetics; D011849:Radioactive Tracers
chemical_list: D009363:Neoplasm Proteins; D009711:Nucleotides; D011849:Radioactive Tracers; D011766:Pyruvate Carboxylase; D005978:Glutathione; D005947:Glucose