Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Rb protein’s role in retina development is key to understanding devastating eye cancer


Data from unique gene function studies show Rb is required for proliferation of retinal cells and development of the light-sensitive rods and gives hints for improving treatment of retinoblastoma

The finding that a tumor-suppressor protein called Rb is required for proper development of the mouse retina is a major step toward understanding why some children develop the devastating eye cancer called retinoblastoma. This discovery should eventually help scientists design a better treatment for this disease, according to investigators at St. Jude Children’s Research Hospital. An article about this research is published in the Feb. 29 issue of Nature Genetics.

The St. Jude team showed that Rb limits the proliferation of immature retinal cells so the retina develops to a normal size. The Rb protein also prompts specific cells to develop into light-sensitive cells called rods.

The study results also offer clues to solving a long-standing paradox, according to Michael A. Dyer, Ph.D., an assistant member of the Department of Neurobiology and senior author of the Nature Genetics article.

"Children who lack the gene for Rb are at high risk for developing retinoblastoma, yet mice that also lack the Rb gene do not develop the disease," Dyer said. "The first step to solving that paradox and understanding why mice without the Rb protein don’t get retinoblastoma is figuring out what that protein does during normal mouse development. Our study was that first step. What we’re learning could eventually help us to block the molecular signals that trigger retinoblastoma in children."

Understanding the development of tissues and organs can also help researchers understand why certain types of pediatric tumors occur. The study provides strong evidence that retinoblastoma is a developmental tumor, caused by a genetic abnormality in a tissue or organ present in the developing embryo. Following birth, this abnormality triggers cancer in that tissue or organ during infancy or childhood.

The St. Jude study also broke new ground in the study of retinal development by overcoming a major obstacle blocking earlier researchers from studying the role of Rb in mice lacking this gene. Normally, such studies would be done in Rb "knockout" mice, in which the Rb gene had been artificially eliminated by researchers. But Rb knockout mice die while still embryos, making it impossible to study the effect of this mutation on the developing retina.

However, Dyer’s team was able to demonstrate the critical roles the Rb protein plays in retinal development by using several unique genetic approaches representing important advances in the study of gene function. These techniques included methods for knocking out Rb from retinal cells that can be studied in a laboratory dish, as well as methods for knocking out Rb in single retinal progenitor cells so the effect of this mutation could be studied in both embryos and newborn mice. A progenitor cell is a "parent" cell that divides and multiplies, giving rise to specific types of cells.

One way the researchers solved the problem of embryos dying from lack of Rb was by taking advantage of the fact that the retina is still developing in newborn mice. The team used a virus to insert a gene for E1A--a protein that inactivates Rb--into newborn mice. The retinas in these newborn mice grew abnormally large and failed to develop rods.

"Our work has also included efforts to develop a mouse model that has the same genetic mutations as those found in humans with retinoblastoma, yet permit the mouse to develop and be born," Dyer said. "This will further enhance our understanding of this devastating cancer and allow us to test new treatments that will spare children with this cancer from losing one or both eyes."

Other authors of the article are Jiakun Zhang and Johnathan Gray (St. Jude); Sheldon Rowan and Constance L. Cepko (Howard Hughes Medical Instutite, Harvard Medical School, Boston); and Xumei Zhu and Cheryl M. Craft (University of Southern California, Los Angeles). This work was supported in part by NIH, the National Cancer Institute and ALSAC.

St. Jude Children’s Research Hospital

St. Jude Children’s Research Hospital is internationally recognized for its pioneering work in finding cures and saving children with cancer and other catastrophic diseases. Founded by late entertainer Danny Thomas, St. Jude freely shares its discoveries with scientific and medical communities around the world. No family ever pays for treatments not covered by insurance, and families without insurance are never asked to pay. St. Jude is financially supported by ALSAC, its fund-raising organization. For more information, please visit

Bonnie Cameron | EurekAlert!
Further information:

More articles from Health and Medicine:

nachricht Breast cancer drug beats superbug
13.10.2015 | University of California - San Diego

nachricht Allergic asthma: UFZ researchers identify a key molecule
12.10.2015 | Helmholtz Centre for Environmental Research (UFZ),

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: Secure data transfer thanks to a single photon

Physicists of TU Berlin and mathematicians of MATHEON are so successful that even the prestigious journal “Nature Communications” reported on their project.

Security in data transfer is an important issue, and not only since the NSA scandal. Sometimes, however, the need for speed conflicts to a certain degree with...

Im Focus: A Light Touch May Help Animals and Robots Move on Sand and Snow

Having a light touch can make a hefty difference in how well animals and robots move across challenging granular surfaces such as snow, sand and leaf litter. Research reported October 9 in the journal Bioinspiration & Biomimetics shows how the design of appendages – whether legs or wheels – affects the ability of both robots and animals to cross weak and flowing surfaces.

Using an air fluidized bed trackway filled with poppy seeds or glass spheres, researchers at the Georgia Institute of Technology systematically varied the...

Im Focus: Reliable in-line inspections of high-strength automotive body parts within seconds

Nondestructive material testing (NDT) is a fast and effective way to analyze the quality of a product during the manufacturing process. Because defective materials can lead to malfunctioning finished products, NDT is an essential quality assurance measure, especially in the manufacture of safety-critical components such as automotive B-pillars. NDT examines the quality without damaging the component or modifying the surface of the material. At this year's Blechexpo trade fair in Stuttgart, Fraunhofer IZFP will have an exhibit that demonstrates the nondestructive testing of high-strength automotive body parts using 3MA. The measurement results are available in a matter of seconds.

To minimize vehicle weight and fuel consumption while providing the highest level of crash safety, automotive bodies are reinforced with elements made from...

Im Focus: Kick-off for a new era of precision astronomy

The MICADO camera, a first light instrument for the European Extremely Large Telescope (E-ELT), has entered a new phase in the project: by agreeing to a Memorandum of Understanding, the partners in Germany, France, the Netherlands, Austria, and Italy, have all confirmed their participation. Following this milestone, the project's transition into its preliminary design phase was approved at a kick-off meeting held in Vienna. Two weeks earlier, on September 18, the consortium and the European Southern Observatory (ESO), which is building the telescope, have signed the corresponding collaboration agreement.

As the first dedicated camera for the E-ELT, MICADO will equip the giant telescope with a capability for diffraction-limited imaging at near-infrared...

Im Focus: Locusts at the wheel: University of Graz investigates collision detector inspired by insect eyes

Self-driving cars will be on our streets in the foreseeable future. In Graz, research is currently dedicated to an innovative driver assistance system that takes over control if there is a danger of collision. It was nature that inspired Dr Manfred Hartbauer from the Institute of Zoology at the University of Graz: in dangerous traffic situations, migratory locusts react around ten times faster than humans. Working together with an interdisciplinary team, Hartbauer is investigating an affordable collision detector that is equipped with artificial locust eyes and can recognise potential crashes in time, during both day and night.

Inspired by insects

All Focus news of the innovation-report >>>



Event News

EHFG 2015: Securing healthcare and sustainably strengthening healthcare systems

01.10.2015 | Event News

Conference in Brussels: Tracking and Tracing the Smallest Marine Life Forms

30.09.2015 | Event News

World Alzheimer`s Day – Professor Willnow: Clearer Insights into the Development of the Disease

17.09.2015 | Event News

Latest News

New Oregon approach for 'nanohoops' could energize future devices

13.10.2015 | Life Sciences

Supercoiled DNA is far more dynamic than the 'Watson-Crick' double helix

13.10.2015 | Life Sciences

Breast cancer drug beats superbug

13.10.2015 | Health and Medicine

More VideoLinks >>>