Therapeutic arginine starvation in ASS1-deficient cancers inhibits the Warburg effect

Abstract

Argininosuccinate Synthetase 1 deficiency induces dependence on extracellular arginine for continued cellular growth and survival. Arginine starvation inhibits the Warburg effect and diverts glucose into serine biosynthesis, while simultaneously increasing glutamine metabolism via the tricarboxylic acid cycle. Simultaneous arginine deprivation and inhibition of the subsequent metabolic adaptations induce synthetic lethality.KEYWORDS ADI-PEG20; arginine deiminase; argininosuccinate synthetase 1; ASS1; glutaminase; metabolism; GLS; glucose; glutamine; PHGDH; Warburg Cancer metabolism represents the next wave of cancer therapeutics after immunotherapy. The alterations in cancer cell metabolism that are currently being investigated result from the dramatic metabolic reprogramming that occurs within cancer for the production of biomass. One of the original metabolic hallmarks was the "Warburg Effect," whereby cancer cells preferentially generate energy through glucose fermentation into lactic acid rather than oxidation through the tricarboxylic acid (TCA) cycle and subsequent oxidative phosphorylation. Other common metabolic alterations in cancer include mutations in isocitrate dehydrogenase, overexpression of pyruvate kinase M2 (PKM2), deficiencies in succinate dehydrogenase and fumarate hydratase, and the loss of argininosuccinate synthetase 1 (ASS1) expression. 1 ASS1 is an enzyme involved in clearance of nitrogenous waste via the urea cycle and de novo arginine biosynthesis. Loss of ASS1 expression forces cells to rely on extracellular arginine for continued growth and survival; however, it appears to offer a tumorigenic advantage as loss of ASS1 expression has been shown to be a prognostic biomarker of reduced metastasis-free and overall survival. ASS1-deficient cells undergo autophagy when exposed to the arginine-depleting agent PEGylated arginine deiminase (ADI-PEG20) and undergo cell death upon simultaneous pharmacological or genetic inhibition of autophagy.2,3 Acquired resistance to ADI-PEG20 occurs via a c-Myc-dependent reexpression of ASS1 and renewed cellular arginine biosynthesis capabilities.4,5 Characterization of the cellular consequences of arginine starvation is essential in order to identify and target the metabolic reprogramming that occurs to inhibit the ability of cancer cells to acquire resistance to ADI-PEG20. These findings are being used to develop a biomarker-driven multiagent metabolic therapy for ASS1-deficient cancers.Metabolic characterization of both short-and long-term ADI-PEG20 treatment has shown significant alterations in global metabolism. 5,6 One of the many alterations of metabolic pathways that occur upon short-term ADI-PEG20 treatment was the significant redirection of cellular glucose. While cancer cells typically ferment the majority of cellular glucose into lactic acid and oxidize lesser amounts via the TCA cycle, ADI-PEG20 caused a decrease in the flux of glucose-derived carbons into both lactate and TCA cycle intermediates. The decrease in glucose flux to lactate ...

A Liquid Chromatography with Tandem Mass Spectrometry-Based Proteomic Analysis of Cells Cultured in DMEM 10% FBS and Chemically Defined Medium Using Human Adipose-Derived Mesenchymal Stem Cells

“…In this study, the proteins expressed only in the CDM group were POTEKP, TAGLN3, TF, MT2A (a key protein involved in endothelial cell proliferation and migration [ 42 ]), HP, DHCR24 (a key protein involved in cell homeostasis and cholesterol biosynthesis [ 43 ]), NQO1 (a key protein involved in cellular adaptation to stress [ 44 ]), and TRAP1 (a key protein of the molecular chaperone involved in the regulation of energetic metabolism in cancer cells [ 45 ]). The proteins expressed only in the DMEM group were PDLIM5 (proteins phosphorylated by AMPK activation that suppress cell migration [ 46 ]), PDLIM7 (a key protein of scaffolds for the formation of multiprotein complexes [ 47 ]), Integrin alpha 5 (ITGA5), ASS1 (an enzyme involved in the clearance of nitrogenous waste via the urea cycle and de novo arginine biosynthesis [ 48 ]), FHL1 (inhibits the growth of cancer cells via G1/S cell cycle arrest [ 49 ]), and voltage-dependent anion channel 3 (VDAC3). These results indicate that the proteins specifically expressed in the CDM and DMEM groups included proteins involved in cell adhesion, cell migration, cell cycle regulation, and lipid metabolism.…”

Systems level profiling of arginine starvation reveals MYC and ERK adaptive metabolic reprogramming

“…The silencing of argininosuccinate synthetase 1 (ASS1) expression disrupts the urea cycle in many types of cancer [1][2][3][4] . Importantly, loss of ASS1 expression renders cancer cells dependent on extracellular arginine, as de novo arginine synthesis is reliant on ASS1 4 .…”

“…To exploit this metabolic deficiency, multiple arginine destruction enzymes have been developed, including arginase, arginine decarboxylase, and arginine deiminase 1,11 . The most clinically relevant is PEGylated arginine deiminase (ADI-PEG20), which is currently in clinical trials 12 .…”

Systems level profiling of arginine starvation reveals MYC and ERK adaptive metabolic reprogramming

“…The loss of a functional urea cycle in many types of cancer results from the silencing of argininosuccinate synthetase 1 (ASS1) expression (Kremer & Van Tine, 2017; Phillips et al , 2013; Khadeir et al , 2017; Keshet et al , 2018). This renders cancer cells dependent on extracellular arginine, as de novo arginine synthesis is reliant on ASS1 (Keshet et al , 2018).…”

“…To exploit this metabolic deficiency, multiple arginine destruction enzymes have been developed, including: arginase, arginine decarboxylase, and arginine deiminase (Zam, 2017; Kremer & Van Tine, 2017). The most clinically relevant is PEGylated arginine deiminase (ADI-PEG20), which is currently in clinical trials.…”