The study, recently published in Molecular Cancer Therapeutics, a journal of the American Association for Cancer Research, is the first to show that treatment with a specific peptide, angiotensin-(1-7), reduces lung tumor growth by inhibiting blood vessel formation.
"If you're diagnosed with lung cancer today, you've got a 15 percent chance of surviving five years – and that's just devastating," said co-lead investigator Patricia E. Gallagher, Ph.D., director of the Molecular Biology Core Laboratory in the Hypertension and Vascular Research Center at the School of Medicine. "Those other 85 people – 85 percent – they're not going to see their kids graduate. They're not going to see their children get married."
The lung cancer survival rate has changed little in the past 30 years, said Gallagher's co-lead investigator, E. Ann Tallant, Ph.D., a professor in the Hypertension and Vascular Research Center – a fact that motivates them in their research.
Peptides, found in all animals, are compounds formed by linking one or more amino acids together through the sharing of electrons. They are among the building blocks of life. Peptides can perform a wide range of functions in the body, depending on which amino acids are involved. Some can regulate hormones, for example, while others can have an antibiotic function.
Angiotensin-(1-7) is a small peptide that binds to proteins on the surface of cells and prevents cell growth – but only if the cell is actively growing when the binding occurs. That property is what led Tallant and Gallagher to explore the peptide's uses for treating cancer by blocking tumor growth.
Angiotensin-(1-7) works by inhibiting the production of signals sent out by a cancer tumor for food. For tumors to grow, they need nutrients delivered by blood vessels. The signals they send prompt blood vessels to grow and invade the tumor to feed it.
Every day during the six-week study, researchers injected either saline or the angiotensin (1-7) peptide into mice growing human lung cancer tumors. Over the course of the study, the tumors treated with angiotensin-(1-7) shrunk, while the saline-treated tumors grew and, at the end of the study, the tumors treated with angiotensin-(1-7) weighed about 60 percent less than the tumors treated with saline. Analysis also showed that the tumors from mice treated with the peptide had significantly fewer blood vessels compared to the tumors from the saline-treated animals.
The researchers further tested angiotensin (1-7)'s affect on blood vessel formation, or angiogenesis, by treating chick embryos with the peptide – a procedure considered the gold standard for determining anti-angiogenic ability. They found that blood vessels continued to grow in a saline-injected control group, while blood vessel formation decreased by more than 50 percent in the embryos treated with angiotensin-(1-7).
Tallant and Gallagher said the treatment likely has applications beyond lung cancer – they have collected data showing it is effective on breast, colon and brain tumors, as well.
The treatment also presents an attractive possibility for future human cancer therapy from a cost perspective, they said.
"Because it's a peptide, it's very small and can be made very easily," Gallagher said. "We sometimes like to say we're the aspirin of cancer therapy."
Co-investigators on the study were graduate students David R. Soto-Pantoja and Jyotsana Menon of the School of Medicine. The study was funded by the Susan G. Komen Breast Cancer Research Foundation, Department of Defense, National Institutes of Health, Unifi, Farley-Hudson Foundation, and Golfers Against Cancer of the Triad.
The first clinical trial of angiotensin-(1-7) has been completed at the School of Medicine and the results are currently being reviewed.
Media Relations Contacts: Jessica Guenzel, firstname.lastname@example.org, (336) 716-3487; Bonnie Davis, email@example.com, (336) 716-4977; or Shannon Koontz, firstname.lastname@example.org, (336) 716-2415.
Wake Forest University Baptist Medical Center (www.wfubmc.edu) is an academic health system comprised of North Carolina Baptist Hospital, Brenner Children's Hospital, Wake Forest University Physicians, and Wake Forest University Health Sciences, which operates the university's School of Medicine and Piedmont Triad Research Park. The system comprises 1,056 acute care, rehabilitation and long-term care beds and has been ranked as one of "America's Best Hospitals" by U.S. News & World Report since 1993. Wake Forest Baptist is ranked 32nd in the nation by America's Top Doctors for the number of its doctors considered best by their peers. The institution ranks in the top third in funding by the National Institutes of Health and fourth in the Southeast in revenues from its licensed intellectual property.
Jessica Guenzel | EurekAlert!
New malaria analysis method reveals disease severity in minutes
14.08.2017 | University of British Columbia
New type of blood cells work as indicators of autoimmunity
14.08.2017 | Instituto de Medicina Molecular
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...
Researchers from the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science, the Italian Space Agency (ASI), and the Instituto Geofisico--Escuela Politecnica Nacional (IGEPN) of Ecuador, showed an increasing volcanic danger on Cotopaxi in Ecuador using a powerful technique known as Interferometric Synthetic Aperture Radar (InSAR).
The Andes region in which Cotopaxi volcano is located is known to contain some of the world's most serious volcanic hazard. A mid- to large-size eruption has...
16.08.2017 | Event News
04.08.2017 | Event News
26.07.2017 | Event News
16.08.2017 | Physics and Astronomy
16.08.2017 | Materials Sciences
16.08.2017 | Interdisciplinary Research