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

03.03.2004


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 www.stjude.org.

Bonnie Cameron | EurekAlert!
Further information:
http://www.stjude.org

More articles from Health and Medicine:

nachricht Study suggests possible new target for treating and preventing Alzheimer's
02.12.2016 | Oregon Health & Science University

nachricht The first analysis of Ewing's sarcoma methyloma opens doors to new treatments
01.12.2016 | IDIBELL-Bellvitge Biomedical Research Institute

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: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

Im Focus: Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

UTSA study describes new minimally invasive device to treat cancer and other illnesses

02.12.2016 | Medical Engineering

Plasma-zapping process could yield trans fat-free soybean oil product

02.12.2016 | Agricultural and Forestry Science

What do Netflix, Google and planetary systems have in common?

02.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>