Hedgehog Signaling Regulates Metabolism and Polarization of Mammary Tumor-Associated Macrophages
Abstract
Elevated infiltration of immunosuppressive alternatively polarized (M2) macrophages is associated with poor prognosis in patients with cancer. The tumor microenvironment remarkably orchestrates molecular mechanisms that program these macrophages. Here we identify a novel role for oncogenic Hedgehog (Hh) signaling in programming signature metabolic circuitries that regulate alternative polarization of tumor-associated macrophages. Two immunocompetent orthotopic mouse models of mammary tumors were used to test the effect of inhibiting Hh signaling on tumor-associated macrophages. Treatment with the pharmacologic Hh inhibitor vismodegib induced a significant shift in the profile of tumor-infiltrating macrophages. Mass spectrometry-based metabolomic analysis showed Hh inhibition induced significant alterations in metabolic processes, including metabolic sensing, mitochondrial adaptations, and lipid metabolism. In particular, inhibition of Hh in M2 macrophages reduced flux through the UDP-GlcNAc biosynthesis pathway. Consequently, O-GlcNAc-modification of STAT6 decreased, mitigating the immune-suppressive program of M2 macrophages, and the metabolically demanding M2 macrophages shifted their metabolism and bioenergetics from fatty acid oxidation to glycolysis. M2 macrophages enriched from vismodegib-treated mammary tumors showed characteristically decreased O-GlcNAcylation and altered mitochondrial dynamics. These Hh-inhibited macrophages are reminiscent of inflammatory (M1) macrophages, phenotypically characterized by fragmented mitochondria. This is the first report highlighting the relevance of Hh signaling in controlling a complex metabolic network in immune cells. These data describe a novel immunometabolic function of Hh signaling that can be clinically exploited.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jul 21, 2021
- Source ID
- 10.1158/0008-5472.can-20-1723
Entities
People
- Ann Hanna
- Atul Kumar
- Brandon J. Metge
- Dominique C. Hinshaw
- Dongquan Chen
- Gloria A. Benavides
- Hebaallah Alsheikh
- Jeffrey C. Rathmell
- Lalita A. Shevde
- Mateus Mota
- Rajeev S Samant
- Sarah C. Kammerud
- Scott W. Ballinger
- Selvarangan Ponnazhagan
- Tshering D Lama-Sherpa
- Victor Darley-usmar
Organizations
- National Cancer Institute
- United States Department of Defense
- University of Alabama at Birmingham
- VU University Medical Center
- Vanderbilt University
- Veterans Health Administration