"Blood from all tissues of the body travels to the lungs for oxygenation, increasing the likelihood that circulating metastatic cells will interact with the lung microvasculature," says Rakesh K. Jain, PhD, director of the Steele Laboratory for Tumor Biology at MGH and senior author of the study. "Identifying factors that prepare this 'hospitable soil' for tumor formation may help us develop strategies to slow or halt that process."
In order to form metastases, cancer cells carried through the bloodstream need to find an environment that allows them to adhere and proliferate. While recent research supports the hypothesis that primary tumors secrete factors that prepare distant sites for potential metastatic development, defining the role of specific factors has been challenging. The current study investigated whether the ability of tumors in other parts of the body to induce formation of distinct areas of abnormal leakiness in lung tissue contributes to the development of metastases.
The researchers first confirmed that either the presence of an implanted tumor or infusions of factors secreted by tumors produced localized areas of leakiness in the lungs of mice. Analysis of the tumor-secreted factors identified specific molecules known to increase vascular permeability, including the angiogenesis-inducing vascular endothelial growth factor (VEGF). Metastatic cells infused into mice treated with either tumor-secreted factors or VEGF preferentially adhered to sites of leaky lung tissue, and both this attraction of tumor cells and the increase in vascular permeability were reduced by blocking VEGF activity.
Since VEGF is known to activate FAK – which plays a role in cellular signaling – in the endothelial cells that line pulmonary blood vessels, the researchers analyzed levels of the enzyme at the sites of induced vascular leakiness and found them to be elevated. "Blocking the activity of FAK in lung endothelial cells reduced both vascular permeability and the adhesion of metastatic cells to those tissues. Additional genetic experiments revealed that FAK produces these effects through increased local expression of the cellular adhesion molecule E-selectin," says Dai Fukumura, MD, PhD, of the Steele Lab, a co-senior author of the report.
Co-senior author Dan G. Duda, DMD, PhD, also of the Steele Lab, adds, "Anti-metastatic therapy is the ultimate frontier for cancer therapy, but existing treatments – both traditional chemotherapy and newer antiangiogenesis agents – have limited effectiveness in preventing the development of metastases. Our findings provide proof of principle that FAK inhibition is a valid antimetastatic strategy that should be investigated in future translational studies."
Jain is the Cook Professor of Radiation Oncology (Tumor Biology), Duda an assistant professor of Radiation Oncology, and Fukumura an associate professor of Radiation Oncology at Harvard Medical School. The lead author of the PNAS paper is Sachie Hiratsuka, MD, PhD, of the Steele Laboratory at MGH. Additional co-authors are Shom Goel, MD, and Walid Kamoun, PhD, Steele Lab; and Yoshiro Maru, MD, PhD, Tokyo Women's Medical University. The study was supported by grants from the National Institutes of Health and other funders.
Celebrating the 200th anniversary of its founding in 1811, Massachusetts General Hospital is the original and largest teaching hospital of Harvard Medical School. The MGH conducts the largest hospital-based research program in the United States, with an annual research budget of nearly $700 million and major research centers in AIDS, cardiovascular research, cancer, computational and integrative biology, cutaneous biology, human genetics, medical imaging, neurodegenerative disorders, regenerative medicine, systems biology, transplantation biology and photomedicine.
Sue McGreevey | EurekAlert!
Newly designed molecule binds nitrogen
23.02.2018 | Julius-Maximilians-Universität Würzburg
Atomic Design by Water
23.02.2018 | Max-Planck-Institut für Eisenforschung GmbH
A newly developed laser technology has enabled physicists in the Laboratory for Attosecond Physics (jointly run by LMU Munich and the Max Planck Institute of Quantum Optics) to generate attosecond bursts of high-energy photons of unprecedented intensity. This has made it possible to observe the interaction of multiple photons in a single such pulse with electrons in the inner orbital shell of an atom.
In order to observe the ultrafast electron motion in the inner shells of atoms with short light pulses, the pulses must not only be ultrashort, but very...
A group of researchers led by Andrea Cavalleri at the Max Planck Institute for Structure and Dynamics of Matter (MPSD) in Hamburg has demonstrated a new method enabling precise measurements of the interatomic forces that hold crystalline solids together. The paper Probing the Interatomic Potential of Solids by Strong-Field Nonlinear Phononics, published online in Nature, explains how a terahertz-frequency laser pulse can drive very large deformations of the crystal.
By measuring the highly unusual atomic trajectories under extreme electromagnetic transients, the MPSD group could reconstruct how rigid the atomic bonds are...
Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...
For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.
In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...
Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale
Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...
15.02.2018 | Event News
13.02.2018 | Event News
12.02.2018 | Event News
23.02.2018 | Physics and Astronomy
23.02.2018 | Health and Medicine
23.02.2018 | Physics and Astronomy