Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


UNC studies target molecular defects implicated in cancer, genetic diseases


In three separate studies, scientists at the University of North Carolina at Chapel Hill School of Medicine have shown that it is possible to correct defective molecular splicing pathways that would otherwise contribute to cancer, genetic diseases and possibly other disorders.

These corrections were accomplished by the insertion into the cell of antisense oligonucleotides, short strands of genetic material that target portions of RNA. RNA carries the DNA blueprint for cellular protein production in gene expression. The technique for correcting these defective molecular splicing pathways was pioneered by Dr. Ryszard Kole, professor of pharmacology and a member of the UNC Lineberger Comprehensive Cancer Center.

In a new study published Dec. 20 in the Journal of Biological Chemistry, Kole and colleagues used these techniques to eradicate certain cancer cells or to increase their sensitivity to treatment.

While tumors initially respond to radiation or chemotherapy, they frequently become resistant to subsequent treatments. One form of resistance develops when cancer cells no longer respond to signaling molecules that tell the cells to die, a process known as apoptosis. In the new report, RNA splicing of the gene that controls apoptosis was targeted with antisense oligonucleotides.

"RNA splicing is the essential process of cutting and pasting the genetic code into a continuous reading frame to produce protein," said Kole. "The cell can splice each RNA into multiple, alternative forms, which result in related but different proteins. In cancer cells, this process may be modified and contribute to resistance to apoptosis."

For example, RNA coded by a gene, bcl-x, is alternately spliced into two different forms, both of which play an important role in apoptosis. The short form, bcl-xS, promotes apoptosis and cell death, while the long form, bcl-xL, prevents apoptosis and promotes cell growth.

Accordingly, higher levels of bcl-xL have been found in malignant cancers of the prostate and have been correlated with increased resistance of these cancers to chemotherapeutic agents. In the new study, antisense molecules were used to shift the alternative splicing of bcl-x from the anti-apoptotic form to the pro-apoptotic form in cancer cell lines, including cancers of the prostate and breast. In doing so, the UNC researchers were able to sensitize these cell lines to various chemotherapeutic agents and radiation.

"Our gene-based therapy would presumably be specific for cancer cells, which overexpress the anti-apoptotic form of RNA," said Dr. Danielle Mercatante, first author of the study and a postdoctoral fellow at the Lineberger center. "This approach could offer a significant advantage over conventional therapies, which are non-specific and kill both cancerous and non-cancerous cells."

This study used cells in culture. But in a December report in Nature Biotechnology, Kole and colleagues demonstrated they could alter splicing defects in a mouse. In this report, they inserted a gene with a splicing defect into the mouse genome. The gene fluoresces bright green when the splicing defect has been successfully blocked with antisense oligonucleotides. Injection of antisense oligonucleotides into the transgenic mouse model blocked defective splicing, leading to green fluorescence activity in several tissues.

"To my knowledge, our study was the first demonstration that a systemically injected oligonucleotide could shift splicing in vivo," said Peter Sazani, first author of the study and postdoctoral researcher at the Lineberger center.

"The transgenic mouse provides a platform to compare the various oligonucleotide modifications that could lead to improvements in the stability, uptake and binding of the oligonucleotides to the target," said Kole. "These improvements will allow the oligonucleotides to modify splicing in patients in the not-too-distant future."

Besides these two reports, the Kole laboratory last year demonstrated the therapeutic potential of this method in blood from patients with a form of beta-thalassemia, a genetic disease that affects as many as one in 10 of the Mediterranean population. The study showed that antisense molecules could be used to increase the production of hemoglobin, the protein necessary to reduce the patient’s anemia. In September, the findings were published in the online edition of the journal Blood, a publication of the American Society of Hematology. They also appear in the Jan.1 issue of the journal.

"Taken together the three reports show the possibility of wide application of targeting splicing with antisense molecules," said Kole. "In fact, recent findings that a large fraction, if not a majority, of genes are alternatively spliced indicate that this approach may be applicable to hundreds of disorders."

The National Heart, Lung and Blood Institute, a component of the National Institutes of Health, provided funding for the research.

By MARLA M. VACEK UNC School of Medicine

Note: Contact Kole at 919-966-1143 or Contact Mercatante at Contact Sazani at School of Medicine contact: Leslie H. Lang, 919-843-9687 or

Leslie Lang | EurekAlert!
Further information:

More articles from Life Sciences:

nachricht Gene therapy shows promise for treating Niemann-Pick disease type C1
27.10.2016 | NIH/National Human Genome Research Institute

nachricht 'Neighbor maps' reveal the genome's 3-D shape
27.10.2016 | International School of Advanced Studies (SISSA)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

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...

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

How nanoscience will improve our health and lives in the coming years

27.10.2016 | Materials Sciences

OU-led team discovers rare, newborn tri-star system using ALMA

27.10.2016 | Physics and Astronomy

'Neighbor maps' reveal the genome's 3-D shape

27.10.2016 | Life Sciences

More VideoLinks >>>