Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Protein fragment found to help improve chemotherapy

21.05.2003


USC researchers find ways to improve effectiveness against tumors



Researchers from the Keck School of Medicine of the University of Southern California have isolated a protein fragment derived from the cancer immunotherapy drug interleukin 2 (IL-2) that seems to enhance the uptake of chemotherapeutic agents into tumors.

In fact, says Alan Epstein, M.D., Ph.D., professor of pathology at the Keck School of Medicine, when this patented protein fragment is attached to a tumor-targeting antibody, it can prompt tumors to soak up more than 300 percent the normal amount of chemotherapy drugs. It does this, Epstein says, by making the tumor’s blood vessel walls more "open" or permeable to the drugs. (Blood vessel walls are made of epithelial cells that are usually tightly joined together; when the junctions between those cells loosen up, it becomes easier for molecules to enter or leave the bloodstream.)


This work was described in a paper being published in the May 21, 2003 issue of the Journal of the National Cancer Institute.

The interleukins are part of a class of proteins called cytokines, which play a role in the human immune response. It’s been hoped that interleukin 2 (IL-2) and its brethren might play a central role in cancer immunotherapy-battling cancer by revving up the immune system. Unfortunately, IL-2 can only be tolerated in small doses by the body. Taken at levels that would take advantage of its therapeutic value, it causes wide-spread edema and other problems due to blood vessel leakiness.

While seeking the cause of this leakiness, Epstein and his Keck School of Medicine colleagues isolated a stretch of 37 amino acids on the IL-2 protein; this sequence, he says, "is responsible for 100 percent of the vasopermeability." Dubbed PEP, for permeability-enhancing peptide, the molecule is now being commercially developed by Peregrine Pharmaceuticals of Tustin, Calif.

Having determined that PEP is indeed a permeability enhancer, Epstein and his colleagues took their exploration a step further: They transplanted mice with human tumor cells and pretreated them with monoclonal antibodies coupled with PEP.

When these mice and control mice were later injected with a radiolabeled tracer antibody or drug, there was a three to four fold increase in the amount of the antibody taken up by the tumors of the pretreated mice than those of the control mice.

"We’ve showed that you can use PEP to induce selective and reversible blood vessel permeability at the tumor site to get better drug uptake," says Epstein. "This may turn out to be a hugely important tool in cancer therapy."

The next step, he says, "is to try to get this product ready to test in human patients."


###
This work was supported by grants from the National Cancer Institute, Peregrine Pharmaceuticals, Inc. and Cancer Therapeutics Laboratories.

Alan L. Epstein, Myra Mizokami, Jiali Li, Peisheng Hu, Leslie A. Khawli, "Identification of a Protein Fragment of Interleukin 2 Responsible for Vasopermeability." Journal of the National Cancer Institute, Vol. 95, No. 10, May 21, 2003, pp. 741-749.

Jon Weiner | EurekAlert!
Further information:
http://www.usc.edu/

More articles from Health and Medicine:

nachricht New High-Performance Center Translational Medical Engineering
26.04.2017 | Fraunhofer ITEM

nachricht A promising target for kidney fibrosis
21.04.2017 | Brigham and Women's Hospital

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: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

Scientist invents way to trigger artificial photosynthesis to clean air

26.04.2017 | Materials Sciences

Ammonium nitrogen input increases the synthesis of anticarcinogenic compounds in broccoli

26.04.2017 | Agricultural and Forestry Science

SwRI-led team discovers lull in Mars' giant impact history

26.04.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>