Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Study may help explain sunlight’s role in melanoma development, have screening implications


A strong link exists between lifetime exposure to ultraviolet light, particularly lifetime sunburns, and the development of melanoma - the most lethal form of skin cancer.

Now, for the first time, scientists have identified a specific molecular pathway within cells that becomes mutated by ultraviolet light exposure, thereby speeding up melanoma development.

New findings published in the Feb. 4 issue of Proceedings of the National Academy of Sciences may have implications for screening people at high risk, including those "with a significant history of sunburn and suspicious skin moles," said study co-author, Dr. Norman Sharpless, assistant professor of medicine and genetics at the University of North Carolina at Chapel Hill School of Medicine and a member of UNC’s Lineberger Comprehensive Cancer Center.

"Who hasn’t been sunburned?" he said. "This work suggests a rational method for risk stratification, for screening questionable skin moles - atypical nevi - for specific molecular lesions."

In the new study, Sharpless and colleagues at Harvard Medical School used mice deficient in an important tumor suppressor protein connected to the "anti-cancer" cell signaling pathway ARF-p53. In addition to this deficiency, these mice were genetically designed to produce another protein, H-Ras, in their pigmented skin cells, or melanocytes.

"Loss of ARF-p53 and activation of Ras are two of three hallmark events detected in human melanomas. The third being loss in another ’anti-cancer’ cell signaling pathway, p16INK4a-Rb," said Sharpless.

This mouse model allowed researchers to selectively test the effects of ultraviolet light exposure on the p16INK4a-Rb pathway.

The Rb pathway regulates cell growth. The retinoblastoma protein acts to hold cell proliferation in check. The regulatory capacity of Rb is moderated by CDK6 and the tumor suppressor protein, p16INK4a.

In this work, the authors showed that ultraviolet light exposure accelerated melanoma formation on the treated mice compared with melanomas arising spontaneously in the absence of such exposure. The researchers found targeting of the Rb pathway, either by an increase in CDK6 expression or a loss of p16INK4a, in the melanomas that developed on mice treated with a single exposure of ultraviolet light - essentially, a mouse sunburn. In mice genetically engineered to lack p16INK4a, however, ultraviolet light exposure did not increase melanoma formation.

"These data suggest that it is not so much this gene or that gene, but the pathway that is what UV light targets," Sharpless said.

"This is one of the better mouse models for any human tumor that I’m aware of," he added. "This finding is unique in that it identifies the Rb pathway as a target of UV’s mutagenic action."

The next research step is to look at a collection of clinical samples to determine if exclusive lesions in the Rb pathway are linked to melanomas from patients with a detailed history of ultraviolet light exposure.

"Melanoma screening is a good idea, but it needs some molecular help to distinguish the really high-risk patients from those at a lower risk for developing melanoma," Sharpless said. "This would be a way to deal with this very large clinically heterogeneous population of patients at risk."

The Howard Hughes Medical Institute and the National Institutes of Health provided funding for the research.

By Kerilyn R. Wick
UNC School of Medicine

Note: Contact Sharpless at (919) 966-1185 or
School of Medicine contact: Les Lang, (919) 843-9687 or

Leslie Lang | EurekAlert!
Further information:

More articles from Health and Medicine:

nachricht Resolving the mystery of preeclampsia
21.10.2016 | Universitätsklinikum Magdeburg

nachricht New potential cancer treatment using microwaves to target deep tumors
12.10.2016 | University of Texas at Arlington

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: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

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

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>