Work

Tumor suppressor RARRES1 links tubulin deglutamylation to mitochondrial metabolism and cell survival

Year: 2019

Type: article

Abstract: // Sara Maimouni 2,* , Mi-Hye Lee 1,* , You-Me Sung 1,* , Michael Hall 1 , Arpita Roy 3 , Chokri Ouaari 1,3 , Yoo-Seok Hwang 4 , Justin Spivak 1 , Eric Glasgow 1 , Matthew Swift 1 , Jay Patel 1 , Amrita Cheema 1 , Deepak Kumar 3 and Stephen Byers 1,2 1 Department of Oncology, Georgetown-Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC, USA 2 Department of Biochemical, Molecular and Cellular Biology, Georgetown University, Washington, DC, USA 3 University of the District of Columbia, Washington, DC, USA 4 Cancer & Developmental Biology Laboratory, National Cancer Institute-Frederick, Frederick, MD, USA * These authors have contributed equally to this article Correspondence to: Stephen Byers, email: [email protected] Keywords : retinoic acid signaling; RARRES1; metabolic reprogramming; PTM tubulin; drug resistance Received: October 09, 2018 Accepted: December 04, 2018 Published: February 26, 2019 Abstract RARRES1, a retinoic acid regulated carboxypeptidase inhibitor associated with fatty acid metabolism, stem cell differentiation and tumorigenesis is among the most commonly methylated loci in multiple cancers but has no known mechanism of action. Here we show that RARRES1 interaction with cytoplasmic carboxypeptidase 2 (CCP2) inhibits tubulin deglutamylation, which in turn regulates the mitochondrial voltage dependent anion channel (VDAC1), mitochondrial membrane potential, AMPK activation, energy balance and metabolically reprograms cells and zebrafish to a more energetic and anabolic phenotype. Depletion of RARRES1 also increases expression of stem cell markers, promotes anoikis, anchorage independent growth and insensitivity to multiple apoptotic stimuli. As depletion of CCP2 or inhibition of VDAC1 reverses the effects of RARRES1 depletion on energy balance and cell survival we conclude that RARRES1 modulation of CCP2-modulated tubulin-mitochondrial VDAC1 interactions is a fundamental regulator of cancer and stem cell metabolism and survival.

Source: Oncotarget

DOI: 10.18632/oncotarget.26600