Authors

Federica Sotgia, Manchester Breast Centre and Breakthrough Breast Cancer Research Unit, Paterson Institute for Cancer Research, Manchester, M20 4BX, UK; The Jefferson Stem Cell Biology and Regenerative Medicine Center; Departments of Stem Cell Biology and Regenerative Medicine, and Cancer Biology, Thomas Jefferson UniversityFollow
Ubaldo E Martinez-Outschoorn, Department of Medical Oncology, Kimmel Cancer Center, Thomas Jefferson University; The Jefferson Stem Cell Biology and Regenerative Medicine Center; Departments of Stem Cell Biology and Regenerative Medicine, and Cancer Biology, Thomas Jefferson University
Stephanos Pavlides, The Jefferson Stem Cell Biology and Regenerative Medicine Center; Departments of Stem Cell Biology and Regenerative Medicine, and Cancer Biology, Thomas Jefferson University
Anthony Howell, Manchester Breast Centre and Breakthrough Breast Cancer Research Unit, Paterson Institute for Cancer Research, Manchester, M20 4BX, UK
Richard G. Pestell, Department of Medical Oncology, Kimmel Cancer Center, Thomas Jefferson University; The Jefferson Stem Cell Biology and Regenerative Medicine Center; Departments of Stem Cell Biology and Regenerative Medicine, and Cancer Biology, Thomas Jefferson UniversityFollow
Michael P Lisanti, Manchester Breast Centre and Breakthrough Breast Cancer Research Unit, Paterson Institute for Cancer Research, Manchester, M20 4BX, UK; Department of Medical Oncology, Kimmel Cancer Center, Thomas Jefferson University; The Jefferson Stem Cell Biology and Regenerative Medicine Center; Departments of Stem Cell Biology and Regenerative Medicine, and Cancer Biology, Thomas Jefferson UniversityFollow

Document Type

Article

Publication Date

7-8-2011

Comments

This article has been peer reviewed and is published in Breast Cancer Research 2011, 13:213. The published version is available at DOI: 10.1186/bcr2892. ┬ęBioMed Central Ltd.

Abstract

Cancer cells show a broad spectrum of bioenergetic states, with some cells using aerobic glycolysis while others rely on oxidative phosphorylation as their main source of energy. In addition, there is mounting evidence that metabolic coupling occurs in aggressive tumors, between epithelial cancer cells and the stromal compartment, and between well-oxygenated and hypoxic compartments. We recently showed that oxidative stress in the tumor stroma, due to aerobic glycolysis and mitochondrial dysfunction, is important for cancer cell mutagenesis and tumor progression. More specifically , increased autophagy/mitophagy in the tumor stroma drives a form of parasitic epithelial-stromal metabolic coupling. These findings explain why it is effective to treat tumors with either inducers or inhibitors of autophagy, as both would disrupt this energetic coupling. We also discuss evidence that glutamine addiction in cancer cells produces ammonia via oxidative mitochondrial metabolism. Ammonia production in cancer cells, in turn, could then help maintain autophagy in the tumor stromal compartment. In this vicious cycle, the initial glutamine provided to cancer cells would be produced by autophagy in the tumor stroma. Thus, we believe that parasitic epithelial-stromal metabolic coupling has important implications for cancer diagnosis and therapy, for example, in designing novel metabolic imaging techniques and establishing new targeted therapies. In direct support of this notion, we identified a loss of stromal caveolin-1 as a marker of oxidative stress, hypoxia, and autophagy in the tumor microenvironment, explaining its powerful predictive value. Loss of stromal caveolin-1 in breast cancers is associated with early tumor recurrence, metastasis, and drug resistance, leading to poor clinical outcome.