Autophagy-dependent metabolic reprogramming sensitizes TSC2-deficient cells to the antimetabolite 6-aminonicotinamide.

Published

Journal Article

UNLABELLED: The mammalian target of rapamycin complex 1 (mTORC1) is hyperactive in many human cancers and in tuberous sclerosis complex (TSC). Autophagy, a key mTORC1-targeted process, is a critical determinant of metabolic homeostasis. Metabolomic profiling was performed to elucidate the cellular consequences of autophagy dysregulation under conditions of hyperactive mTORC1. It was discovered that TSC2-null cells have distinctive autophagy-dependent pentose phosphate pathway (PPP) alterations. This was accompanied by enhanced glucose uptake and utilization, decreased mitochondrial oxygen consumption, and increased mitochondrial reactive oxygen species (ROS) production. Importantly, these findings revealed that the PPP is a key autophagy-dependent compensatory metabolic mechanism. Furthermore, PPP inhibition with 6-aminonicotinamide (6-AN) in combination with autophagy inhibition suppressed proliferation and prompted the activation of NF-κB and CASP1 in TSC2-deficient, but not TSC2-proficient cells. These data demonstrate that TSC2-deficient cells can be therapeutically targeted, without mTORC1 inhibitors, by focusing on their metabolic vulnerabilities. IMPLICATIONS: This study provides proof-of-concept that therapeutic targeting of diseases with hyperactive mTORC1 can be achieved without the application of mTORC1 inhibitors.

Full Text

Duke Authors

Cited Authors

  • Parkhitko, AA; Priolo, C; Coloff, JL; Yun, J; Wu, JJ; Mizumura, K; Xu, W; Malinowska, IA; Yu, J; Kwiatkowski, DJ; Locasale, JW; Asara, JM; Choi, AMK; Finkel, T; Henske, EP

Published Date

  • January 2014

Published In

Volume / Issue

  • 12 / 1

Start / End Page

  • 48 - 57

PubMed ID

  • 24296756

Pubmed Central ID

  • 24296756

Electronic International Standard Serial Number (EISSN)

  • 1557-3125

Digital Object Identifier (DOI)

  • 10.1158/1541-7786.MCR-13-0258-T

Language

  • eng

Conference Location

  • United States