Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Loss of cell adhesion protein drives esophageal and oral cancers in mice

13.04.2011
Findings might lead to targets for therapy, early detection

Squamous cell cancers of the oral cavity and esophagus are common throughout the world, with over 650,000 cases of oral cancer each year and esophageal cancer representing the sixth most common cause of cancer death in men.

Research by University of Pennsylvania School of Medicine investigators has shown that a protein that helps cells stick together is frequently absent or out of place in these cancers, but it's unclear if its loss causes the tumors.

The investigators report that mice engineered to lack this protein, called p120-catenin (p120ctn), in the oral-upper digestive tract develop squamous cell cancers. The data, reported Cancer Cell, settle a 20-year debate and prove that p120ctn is a tumor-suppressor protein. What's more, the tumors that form in this mouse model closely resemble human disease and may point the way to novel therapies and early detection strategies.

"As the mice aged, what we saw was a dramatic evolution of precancer to cancer," says senior author Anil K. Rustgi, MD, the T. Grier Miller Professor of Medicine and Genetics and chief of Gastroenterology. "Both the precancerous growth, called dysplasia, and the cancer look exactly like what we see in humans. This is really exciting because it supports efforts for prevention and early detection, especially in people who drink alcohol and smoke cigarettes excessively and are at high risk for the disease in many regions of the world."

In healthy tissues, p120ctn is part of a protein complex that holds epithelial cells in tightly packed sheets. When p120ctn (or another of these cell adhesion proteins) is lost, a wide variety of cancers including those in prostate, breast, pancreas, colon, skin, bladder, and the endometrium, can result.

The cells lose their tight cell-cell contacts and can migrate more easily, which likely favors cancer spread and invasion of new cells. However, earlier attempts to test the effects of p120ctn loss on cancer formation were derailed because the animals cannot survive throughout embryonic development or immediately after birth without the protein.

To get around that problem, Rustgi and colleagues used a system called Cre-Lox that allows them to remove a particular gene in only a subset of tissues. In this case, the team deleted p120ctn from the oral cavity, esophagus and forestomach. The mutant animals survived through early development and birth, but by 4 to 6 months, most of the mutant animals had developed precancerous lesions and by 9 to 12 months, 70 percent of the mutant animals had full blown tumors. By contrast, none of the control littermates developed cancer.

The investigators noted that as the lesions developed, the tumor cells secreted inflammatory signals that acted like homing signals for immune cells called immature myeloid cells. These cells, in turn, helped to create a microenvironment that supported tumor growth. In fact, when the researchers blocked recruitment of the immune cells, they saw a dramatic reduction in tumor invasion.

Based on these observations, Rustgi thinks that targeting the immature myeloid cells may reverse or slow tumor grown in humans, although more work needs to be done in animal models before the approach is tested in the clinic.

Rustgi says that the mouse model will help test innovative therapies and early detection tests. He says that although he was born and raised in the United States, he was influenced by five years he spent as a child in India, where oral cancer is common due to the proportion of the population that chews betel nuts. "I remember, even as a little kid, I would see people with oral lesions," he says. "I didn't know what they were then, but it has always motivated me at a personal level. Esophageal cancer biology has also been a long-standing interest of mine because it affects so many underserved people in the inner cities in the United States."

The first author on the study is Douglas B. Stairs from the University of Pennsylvania. Co-authors on the study include Lauren J. Bayne, Ben Rhoades, Maria E. Vega, Todd J. Waldron, Jiri Kalabis, Jonathan P. Katz, J. Alan Dieh, and Robert H. Vonderheide from the University of Pennsylvania, Andres Klein-Szanto from Fox Chase Cancer Center in Philadelphia, Ju-Seog Lee from the University of Texas MD Anderson Cancer Center in Houston, and Albert B. Reynolds from Vanderbilt University in Nashville.

The study was funded through grants from the National Cancer Institute and the National Institute of Diabetes and Digestive and Kidney Diseases.

Penn Medicine is one of the world's leading academic medical centers, dedicated to the related missions of medical education, biomedical research, and excellence in patient care. Penn Medicine consists of the University of Pennsylvania School of Medicine (founded in 1765 as the nation's first medical school) and the University of Pennsylvania Health System, which together form a $4 billion enterprise.

Penn's School of Medicine is currently ranked #2 in U.S. News & World Report's survey of research-oriented medical schools and among the top 10 schools for primary care. The School is consistently among the nation's top recipients of funding from the National Institutes of Health, with $507.6 million awarded in the 2010 fiscal year.

The University of Pennsylvania Health System's patient care facilities include: The Hospital of the University of Pennsylvania â€" recognized as one of the nation's top 10 hospitals by U.S. News & World Report; Penn Presbyterian Medical Center; and Pennsylvania Hospital – the nation's first hospital, founded in 1751. Penn Medicine also includes additional patient care facilities and services throughout the Philadelphia region.

Penn Medicine is committed to improving lives and health through a variety of community-based programs and activities. In fiscal year 2010, Penn Medicine provided $788 million to benefit our community.

Karen Kreeger | EurekAlert!
Further information:
http://www.uphs.upenn.edu

More articles from Life Sciences:

nachricht A Map of the Cell’s Power Station
18.08.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau

nachricht On the way to developing a new active ingredient against chronic infections
18.08.2017 | Deutsches Zentrum für Infektionsforschung

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

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...

Im Focus: Circular RNA linked to brain function

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...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

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...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

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...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

A Map of the Cell’s Power Station

18.08.2017 | Life Sciences

Engineering team images tiny quasicrystals as they form

18.08.2017 | Physics and Astronomy

Researchers printed graphene-like materials with inkjet

18.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>