How cancer metastasis occurs
Larry H. Bernstein, MD, FCAP, Curator
LPBI
UPDATED 08/03/2026
From AACR Cancer Discovery Blog: https://www.aacr.org/blog/2025/05/09/editors-picks-april-2025-brain-cancer-evolution-new-treatment-approaches-and-more/
The following paper shows in-vivo evidence that lung cancer metastasis is tightly linked with alterations and metabolic intermediates in the Tricarboxylic Acid (TCA) Cycle.
Cai L, Hammond NG, Tasdogan A, Alsamraae M, Yang C, Cameron RB, Quan P, Solmonson A, Gu W, Pachnis P, Kaur M, Chang BK, Zhou Q, Hensley CT, Do QN, Martins Nascentes Melo L, Ubellacker JM, Kaushik A, Clare MG, Alcazar IN, Kurylowicz K, Marcuccilli JD, Allies G, Kutritz A, Klode J, Ramesh V, Rogers TJ, Rao AD, Crentsil HE, Li H, Brister F, McDaniel P, Xu X, Evers BM, Zacharias LG, Sudderth J, Xu J, Mathews TP, Oliver D, Minna JD, Waters J, Morrison SJ, Kernstine KH, Faubert B, DeBerardinis RJ. High Glucose Contribution to the TCA Cycle Is a Feature of Aggressive Non-Small Cell Lung Cancer in Patients. Cancer Discov. 2025 Apr 2;15(4):702-716. doi: 10.1158/2159-8290.CD-23-1319.
In patients with non-small cell lung cancer (NSCLC), the relationship between tumor metabolism and clinical outcomes is unknown. Here, 13C-labeled nutrients were intraoperatively infused into more than 90 patients with surgically resectable pulmonary lesions, and metabolic properties of resected tumors were correlated with survival. In NSCLCs infused with 13C-glucose, high 13C enrichment in tricarboxylic acid (TCA) cycle intermediates conferred a HR of 3.8 for early death, typically with metastasis. To test whether these features reflect requirements for metastasis, we generated patient-derived xenografts that spontaneously metastasize to multiple organs. Treatment with an electron transport chain (ETC) inhibitor reduced glucose-derived TCA cycle labeling but did not suppress subcutaneous tumor growth. However, ETC blockade reduced the abundance of circulating cancer cells and suppressed xenograft metastatic burden in distant organs. Our data demonstrate that isotope labeling can identify metabolic properties associated with metastasis in patients and that blocking the ETC suppresses metastasis in mice.
Figure Legend:
Inhibition of complex I with IACS-010759 limits metastasis in NSCLC PDXs. A and B, Tumor-bearing mice were treated daily with DMSO or IACS-010759 (5 mg/kg) by oral gavage for 3–4 weeks and then infused with [U-13C]glucose for 3 hours. Overall TCA cycle enrichment was calculated as the sum of isotopologues of citrate, malate, and glutamate and compared between DMSO- and IACS-010759–treated groups. C and D, Subcutaneous tumor volume calculated as (L × W2)/2. Each line represents the growth pattern of an individual tumor. E, Flow cytometry analysis of circulating tumor cells in the blood of mice engrafted with mx148. Cells were assessed for hCD45 and HLA. F and G, Lung and brain metastases from mx148 were evaluated by flow cytometry for mouse lineage markers and hCD45 and HLA. H, Metastatic burden in the lung from mx73 was assessed by flow cytometry, as above. I, Bioluminescence measurements of lung metastases. Representative BLI image (left) and quantitation (right) are displayed. J, Metastatic burden in the brain from mx73 was measured by flow cytometry. K, Schematic of the survival surgery approach to assess the impact of IACS-010759 on established metastases. L, Measurement of axillary lymph nodes containing macrometastases. M, Representative bioluminescence images of axillary lymph nodes. N and O, Metastatic burden in the lung (N) and brain (O) at the time of resection of the subcutaneous tumor (baseline) and after 2.5 weeks of treatment with DMSO or IACS-010759 subsequent to tumor resection. All data are expressed as average and SD. Statistical significance was assessed using Mann–Whitney or t tests to compare treatment groups. The number of mice tested and the number of mice with measurable metastases are indicated in each graph. CTCs, circulating tumor cells; LN, lymph node. *, P<0.05; **, P<0.01. NS, not significant. Source: https://aacrjournals.org/cancerdiscovery/article/15/4/702/754380/High-Glucose-Contribution-to-the-TCA-Cycle-Is-a
Significance: Intraoperative 13C-glucose infusions in patients with NSCLC show that tumors with high labeling of TCA cycle intermediates progress rapidly, resulting in metastasis and early death. Blocking this pathway suppresses metastasis of human NSCLC cells in mice.
Original Article
How Cancer Cells Slide along Narrow Path to Metastasis
In tumors, abnormal protein-fiber environments and genetic perturbations conspire to give rise to metastatic behavior. In this looking-glass world, cells that bump into each other do not halt and reverse direction, as they ordinarily would. Instead, they slide around each other, enhancing migratory potential and bringing to mind the portmanteau “slithy,” which Lewis Carroll invented to describe the behavior of some of his imaginary creatures.
Slithy cancer cells do gyre and gimble in the tumor microenvironment, a looking-glass world in which abnormal protein-fiber scaffolds and genetic perturbations coincide, creating conditions that promote metastasis. Some cancer cells manage to circumnavigate or slide around other cells on protein fibers, and these cells can take relatively straightforward paths out of a primary tumor. Other cells, however, are more likely to turn back upon encountering other cells. They exit tumors less efficiently.
To understand how some cancer cells migrate more efficiently than others, researchers based at Northeastern University undertook a biophysical study. They developed a model environment that mimics protein fibers. First they stamped stripes of a protein called fibronectin on glass plates, making sure to represent various widths. Then they deposited the cells—alternately hundreds of breast cancer cells and hundreds of normal cells—on these fiberlike stripes and used a microscope with time-lapse capabilties to observe and quantify their behavior.
On fibers that were 6 or 9 microns wide—the typical size of fibers in tumors—half the breast cancer cells elongated and slid around the cells they collided with. Conversely, 99% of the normal breast cells did an about face.
To understand what gave the cancer cells this remarkable agility, the Northeastern researchers, led by Anand Asthagiri, explored the influence of fiber widths and genetic perturbations. They presented their results April 26 in the Biophysical Journal, in an article entitled, “Regulators of Metastasis Modulate the Migratory Response to Cell Contact under Spatial Confinement.”
“Downregulating the cell–cell adhesion protein, E-cadherin, enables MCF-10A cells to slide on narrower micropatterns; meanwhile, introducing exogenous E-cadherin in metastatic MDA-MB–231 cells increases the micropattern dimension at which they slide,” wrote the article’s authors.
This finding led the Northeastern team to consider the characteristic fibrillar dimension (CFD) at which effective sliding is achieved as a metric of sliding ability under spatial confinement.
“Using this metric, we show that metastasis-promoting genetic perturbations enhance cell sliding and reduce CFD,” the article’s authors continued. “Activation of ErbB2 combined with downregulation of the tumor suppressor and cell polarity regulator, PARD3, reduced the CFD, in agreement with their cooperative role in inducing metastasis in vivo. The CFD was further reduced by a combination of ErbB2 activation and transforming growth factor β stimulation, which is known to enhance invasive behavior.”
Asthagiri’s system is relatively easy to construct and suited for rapid imaging—two qualities that make it an excellent candidate for screening new cancer drugs. Pharmaceutical companies could input the drugs along with the cancer cells and measure how effectively they inhibit sliding.
In the future, the system could also alert cancer patients and clinicians before metastasis starts. Studies with patients have shown that the structure of a tumor’s protein-fiber scaffolding can indicate how far the disease has progressed. The researchers found that certain aggressive genetic mutations enabled cells to slide on very narrow fibers, whereas cells with milder mutations would slide only when the fibers got much wider. Clinicians could biopsy the tumor and measure the width of the fibers to see if that danger point were approaching. “We can start to say, ‘If these fibers are approaching X microns wide, it’s urgent that we hit certain pathways with drugs,” said Asthagiri.
Questions, of course, remain. Do other types of cancer cells also have the ability to slide? What additional genes play a role?
Next steps, says Asthagiri, include expanding their fiberlike stripes into three-dimensional models that more closely represent the fibers in actual tumors and testing cancer and normal cells together. “There are so many types of cells in a tumor environment—immune cells, blood cells, and so on,” he noted. “We want to better emulate what’s happening in the body rather than in isolated cells interacting on a platform.”
The breast tumor microenvironment (TMEN) is a unique niche where protein fibers help to promote invasion and metastasis. Cells migrating along these fibers are constantly interacting with each other. How cells respond to these interactions has important implications. Cancer cells that circumnavigate or slide around other cells on protein fibers take a less tortuous path out of the primary tumor; conversely, cells that turn back upon encountering other cells invade less efficiently. The contact response of migrating cancer cells in a fibrillar TMEN is poorly understood. Here, using high-aspect ratio micropatterns as a model fibrillar platform, we show that metastatic cells overcome spatial constraints to slide effectively on narrow fiber-like dimensions, whereas nontransformed MCF-10A mammary epithelial cells require much wider micropatterns to achieve moderate levels of sliding. Downregulating the cell-cell adhesion protein, E-cadherin, enables MCF-10A cells to slide on narrower micropatterns; meanwhile, introducing exogenous E-cadherin in metastatic MDA-MB-231 cells increases the micropattern dimension at which they slide. We propose the characteristic fibrillar dimension (CFD) at which effective sliding is achieved as a metric of sliding ability under spatial confinement. Using this metric, we show that metastasis-promoting genetic perturbations enhance cell sliding and reduce CFD. Activation of ErbB2 combined with downregulation of the tumor suppressor and cell polarity regulator, PARD3, reduced the CFD, in agreement with their cooperative role in inducing metastasis in vivo. The CFD was further reduced by a combination of ErbB2 activation and transforming growth factor β stimulation, which is known to enhance invasive behavior. These findings demonstrate that sliding is a quantitative property and a decrease in CFD is an effective metric to understand how multiple genetic hits interact to change cell behavior in fibrillar environments. This quantitative framework sheds insights into how genetic perturbations conspire with fibrillar maturation in the TMEN to drive the invasive behavior of cancer cells.
There was a nice paper a few years ago by Dr. Edna Cukerman from Fox Chase showing how tumor cells slid down on fiber tracks generated from tumor stromal cells and how this pattern of movement is not as random as one would think. if extracellular matrix was generated from normal stromal cells you would not find athis type of coordinated movement.
Fatty acid oxidation disruption: a therapeutic alternative for triple negative breast cancer
Hormone therapy is ineffective against triple negative breast cancers (TNBC) as they lack HER2, Estrogen, and Progesterone receptors. Therefore new targetable pathways are needed to halt the cancer’s progression. Researchers at UCSF have outlined a means of treating TNBC through disruption of fatty acid oxidation (FAO). The pathway was first revealed as a potential target through metabolomics and gene signatures, identifying upregulated FAO intermediates in MYC-overexpressing TNBC samples. Considering the location, in the proximity of adipose-rich mammary glands, breast cancer FAO dependence pathway seemed to be a logical pathway. Subsequent inhibition of FAO with etomixir , an inhibitor of a major enzyme carnitine palmitoyltransferase 1 (CPT1) in the FAO pathway, lead to dramatic decreases in ATP production in MYC-overexpressing cell lines. Although a decrease in proliferation of cells in culture was observed viability remained unchanged. However, further testing of etomixir in vivo within patient derived xenograft models increased success of FAO disruption with a 4 to 6-fold decrease in relative tumor volume. The differential performance between in vitro and in vivo treatments indicates a need to recapitulate the actual tumor environment when studying metabolic manipulation regimens.
Camarda, et. al. Inhibition of fatty acid oxidation as a therapy for MYC-overexpressing triple-negative breast cancer. Nature Medicine
Inhibition of fatty acid oxidation as a therapy for MYC-overexpressing triple-negative breast cancer
Roman Camarda, Alicia Y Zhou, Rebecca A Kohnz,….,Daniel K Nomura & Andrei Goga
Nature Medicine22,427–432(2016) http://dx.doi.org:/10.1038/nm.4055
Expression of the oncogenic transcription factor MYC is disproportionately elevated in triple-negative breast cancer (TNBC), as compared to estrogen receptor–, progesterone receptor– or human epidermal growth factor 2 receptor–positive (RP) breast cancer1, 2. We and others have shown that MYC alters metabolism during tumorigenesis3, 4. However, the role of MYC in TNBC metabolism remains mostly unexplored. We hypothesized that MYC-dependent metabolic dysregulation is essential for the growth of MYC-overexpressing TNBC cells and may identify new therapeutic targets for this clinically challenging subset of breast cancer. Using a targeted metabolomics approach, we identified fatty acid oxidation (FAO) intermediates as being dramatically upregulated in a MYC-driven model of TNBC. We also identified a lipid metabolism gene signature in patients with TNBC that were identified from The Cancer Genome Atlas database and from multiple other clinical data sets, implicating FAO as a dysregulated pathway that is critical for TNBC cell metabolism. We found that pharmacologic inhibition of FAO catastrophically decreased energy metabolism in MYC-overexpressing TNBC cells and blocked tumor growth in a MYC-driven transgenic TNBC model and in a MYC-overexpressing TNBC patient–derived xenograft. These findings demonstrate that MYC-overexpressing TNBC shows an increased bioenergetic reliance on FAO and identify the inhibition of FAO as a potential therapeutic strategy for this subset of breast cancer.
3 Dimensional Ex-Vivo for In-situ Tumor Growth
Brain tumors are both difficult to treat and hard to study because of the organ they affect. The structure of the brain is extremely sensitive to alterations. Until recently the study of architectural alterations and their effects was mostly restricted to in vivo experiments. Typical culturing of brain tissue requires disaggregation and manipulation into a 2-dimensional format, losing any anatomically relevant structure. To study the in situ brain structure, a new technique has been described by researchers from the University of Erlangen-Nürnberg. By carefully sectioning the brains of 4 day-old mice and placing them on a 0.4 uM pore-size transwell membrane 6 well plate insert within required culture medium, they were able to study the endogenous structure under varying conditions. They injected astrocytes or glioma cells with a micropipette into the slices, and investigated the structural changes brain tumors effect in their environment. Termed the Vascular Organotypic Glioma Impact Model (VOGIM), it revealed all the characteristic pathological alterations normally associated with the disease in vivo such as tumor size and borders, vessel length, vessel junctions, and vessel branches, microglia, cell survival, and neuronal modifications. As this method allows for live cell fluorescent observation, they employed the technique to observe cultures treated with the chemotherapeutic Temozolamide (TMZ, Temodal/Temcad®). Indeed they found reduced tumor growth in treatment groups vs controls, but also revealed surprising reduction in microglial cells in the peritumoral region. Additionally, they were able to observe the lack of response TMZ elicited from microglial in healthy regions of the tissue, despite its overall reduction in vascularization towards normal levels. The VOGIM technique allows for ex vivo study of brain tissue requiring three dimensional measurements, but may also be extended to other tissues with unique morphology such as kidney, liver, and intestine.
Ghoochani, et al. (December, 2015) A versatile ex vivo technique for assaying tumor angiogenesis and microglia in the brain ONCOTARGET
A versatile ex vivo technique for assaying tumor angiogenesis and microglia in the brain
Ali Ghoochani1, Eduard Yakubov1, Tina Sehm1, Zheng Fan1, Stefan Hock1, Michael Buchfelder1, Ilker Y. Eyüpoglu1,*, Nicolai Savaskan1,*
http://dx.doi.org:/10.18632/oncotarget.6550 PDF | HTML
Primary brain tumors are hallmarked for their destructive activity on the microenvironment and vasculature. However, solely few experimental techniques exist to access the tumor microenvironment under anatomical intact conditions with remaining cellular and extracellular composition. Here, we detail an ex vivo vascular glioma impact method (VOGIM) to investigate the influence of gliomas and chemotherapeutics on the tumor microenvironment and angiogenesis under conditions that closely resemble the in vivo situation. We generated organotypic brain slice cultures from rats and transgenic mice and implanted glioma cells expressing fluorescent reporter proteins. In the VOGIM, tumor-induced vessels presented the whole range of vascular pathologies and tumor zones as found in human primary brain tumor specimens. In contrast, non-transformed cells such as primary astrocytes do not alter the vessel architecture. Vascular characteristics with vessel branching, junctions and vessel length are quantitatively assessable as well as the peritumoral zone. In particular, the VOGIM resembles the brain tumor microenvironment with alterations of neurons, microglia and cell survival. Hence, this method allows live cell monitoring of virtually any fluorescence-reporter expressing cell. We further analyzed the vasculature and microglia under the influence of tumor cells and chemotherapeutics such as Temozolamide (Temodal/Temcad®). Noteworthy, temozolomide normalized vasculare junctions and branches as well as microglial distribution in tumor-implanted brains. Moreover, VOGIM can be facilitated for implementing the 3Rs in experimentations. In summary, the VOGIM represents a versatile and robust technique which allows the assessment of the brain tumor microenvironment with parameters such as angiogenesis, neuronal cell death and microglial activity at the morphological and quantitative level.
2012pharmaceutical
sjwilliamspa