TY - JOUR
T1 - Oxidative stress in cancer associated fibroblasts drives tumor-stroma co-evolution
T2 - A new paradigm for understanding tumor metabolism, the field effect and genomic instability in cancer cells
AU - Martinez-Outschoorn, Ubaldo E.
AU - Balliet, Renee M.
AU - Rivadeneira, Dayana B.
AU - Chiavarina, Barbara
AU - Pavlides, Stephanos
AU - Wang, Chenguang
AU - Whitaker-Menezes, Diana
AU - Daumer, Kristin M.
AU - Lin, Zhao
AU - Witkiewicz, Agnieszka K.
AU - Flomenberg, Neal
AU - Howell, Anthony
AU - Pestell, Richard G.
AU - Knudsen, Erik S.
AU - Sotgia, Federica
AU - Lisanti, Michael P.
N1 - Funding Information:
M.P.L. and his laboratory were supported by grants from the NIH/NCI (R01-CA-080250; R01-CA-098779; R01-CA-120876; R01-AR-055660) and the Susan G. Komen Breast Cancer Foundation. F.S. was supported by grants from the Breast Cancer Alliance (BCA) and a Research Scholar Grant from the American Cancer Society (ACS). R.G.P. was supported by grants from the NIH/NCI (R01-CA-70896, R01-CA-75503, R01-CA-86072 and R01-CA-107382) and the Dr. Ralph and Marian C. Falk Medical Research Trust. The Kimmel Cancer Center was supported by the NIH/NCI Cancer Center Core grant P30-CA-56036 (to R.G.P.). Funds were also contributed by the Margaret Q. Landenberger Research Foundation (to M.P.L.). This project is funded, in part, under a grant with the Pennsylvania Department of Health (to M.P.L.). The Department specifically disclaims responsibility for any analyses, interpretations or conclusions. This work was also supported, in part, by a Centre grant in Manchester from Breakthrough Breast Cancer in the U.K. (to A.H.) and an Advanced ERC Grant from the European Research Council.
PY - 2010/8/15
Y1 - 2010/8/15
N2 - Loss of stromal fibroblast caveolin-1 (Cav-1) is a powerful single independent predictor of poor prognosis in human breast cancer patients, and is associated with early tumor recurrence, lymph node metastasis and tamoxifen-resistance. We developed a novel co-culture system to understand the mechanism(s) by which a loss of stromal fibroblast Cav-1 induces a "lethal tumor micro-environment." Here, we propose a new paradigm to explain the powerful prognostic value of stromal Cav-1. In this model, cancer cells induce oxidative stress in cancer-associated fibroblasts, which then acts as a "metabolic" and "mutagenic" motor to drive tumor-stroma co-evolution, DNA damage and aneuploidy in cancer cells. More specifically, we show that an acute loss of Cav-1 expression leads to mitochondrial dysfunction, oxidative stress and aerobic glycolysis in cancer associated fibroblasts. Also, we propose that defective mitochondria are removed from cancer-associated fibroblasts by autophagy/mitophagy that is induced by oxidative stress. As a consequence, cancer associated fibroblasts provide nutrients (such as lactate) to stimulate mitochondrial biogenesis and oxidative metabolism in adjacent cancer cells (the "Reverse Warburg Effect"). We provide evidence that oxidative stress in cancer-associated fibroblasts is sufficient to induce genomic instability in adjacent cancer cells, via a bystander effect, potentially increasing their aggressive behavior. Finally, we directly demonstrate that nitric oxide (NO) over-production, secondary to Cav-1 loss, is the root cause for mitochondrial dysfunction in cancer associated fibroblasts. In support of this notion, treatment with anti-oxidants (such as N-acetyl-cysteine, metformin and quercetin) or NO inhibitors (L-NAME) was sufficient to reverse many of the cancer-associated fibroblast phenotypes that we describe. Thus, cancer cells use "oxidative stress" in adjacent fibroblasts (i) as an "engine" to fuel their own survival via the stromal production of nutrients and (ii) to drive their own mutagenic evolution towards a more aggressive phenotype, by promoting genomic instability. We also present evidence that the "field effect" in cancer biology could also be related to the stromal production of ROS and NO species. eNOS-expressing fibroblasts have the ability to downregulate Cav-1 and induce mitochondrial dysfunction in adjacent fibroblasts that do not express eNOS. As such, the effects of stromal oxidative stress can be laterally propagated, amplified and are effectively "contagious" - spread from cell-to-cell like a virus - creating an "oncogenic/mutagenic" field promoting widespread DNA damage.
AB - Loss of stromal fibroblast caveolin-1 (Cav-1) is a powerful single independent predictor of poor prognosis in human breast cancer patients, and is associated with early tumor recurrence, lymph node metastasis and tamoxifen-resistance. We developed a novel co-culture system to understand the mechanism(s) by which a loss of stromal fibroblast Cav-1 induces a "lethal tumor micro-environment." Here, we propose a new paradigm to explain the powerful prognostic value of stromal Cav-1. In this model, cancer cells induce oxidative stress in cancer-associated fibroblasts, which then acts as a "metabolic" and "mutagenic" motor to drive tumor-stroma co-evolution, DNA damage and aneuploidy in cancer cells. More specifically, we show that an acute loss of Cav-1 expression leads to mitochondrial dysfunction, oxidative stress and aerobic glycolysis in cancer associated fibroblasts. Also, we propose that defective mitochondria are removed from cancer-associated fibroblasts by autophagy/mitophagy that is induced by oxidative stress. As a consequence, cancer associated fibroblasts provide nutrients (such as lactate) to stimulate mitochondrial biogenesis and oxidative metabolism in adjacent cancer cells (the "Reverse Warburg Effect"). We provide evidence that oxidative stress in cancer-associated fibroblasts is sufficient to induce genomic instability in adjacent cancer cells, via a bystander effect, potentially increasing their aggressive behavior. Finally, we directly demonstrate that nitric oxide (NO) over-production, secondary to Cav-1 loss, is the root cause for mitochondrial dysfunction in cancer associated fibroblasts. In support of this notion, treatment with anti-oxidants (such as N-acetyl-cysteine, metformin and quercetin) or NO inhibitors (L-NAME) was sufficient to reverse many of the cancer-associated fibroblast phenotypes that we describe. Thus, cancer cells use "oxidative stress" in adjacent fibroblasts (i) as an "engine" to fuel their own survival via the stromal production of nutrients and (ii) to drive their own mutagenic evolution towards a more aggressive phenotype, by promoting genomic instability. We also present evidence that the "field effect" in cancer biology could also be related to the stromal production of ROS and NO species. eNOS-expressing fibroblasts have the ability to downregulate Cav-1 and induce mitochondrial dysfunction in adjacent fibroblasts that do not express eNOS. As such, the effects of stromal oxidative stress can be laterally propagated, amplified and are effectively "contagious" - spread from cell-to-cell like a virus - creating an "oncogenic/mutagenic" field promoting widespread DNA damage.
KW - Aneuploidy
KW - Anti-oxidant cancer therapy
KW - Autophagy
KW - Cancer associated fibroblasts
KW - Caveolin-1
KW - DNA damage
KW - Genomic instability
KW - In cancer biology
KW - Mitochondrial dysfunction
KW - Nitric oxide (NO)
KW - Oxidative stress
KW - Reactive oxygen species (ROS)
KW - The "field effect"
UR - http://www.scopus.com/inward/record.url?scp=77954162846&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=77954162846&partnerID=8YFLogxK
U2 - 10.4161/cc.9.16.12553
DO - 10.4161/cc.9.16.12553
M3 - Article
C2 - 20814239
AN - SCOPUS:77954162846
SN - 1538-4101
VL - 9
SP - 3256
EP - 3276
JO - Cell Cycle
JF - Cell Cycle
IS - 16
ER -