Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers map new path to colon cancer therapy

16.12.2008
University of Texas Medical Branch at Galveston researchers have identified a promising new target in the battle against colorectal cancer — a biochemical pathway critical to the spread of tumors to new locations in the body.

If this "survival pathway" can be successfully blocked under clinical conditions, the result would be a much-needed new therapy for colorectal cancer, the second leading cause of cancer death in the United States.

The researchers' findings, published online the week of December 15 in the Proceedings of the National Academy of Sciences, focus on an enzyme known as Akt2, which is often also found at high levels in association with prostate, ovarian, breast and pancreatic cancers.

Drawing on data from human colorectal cancer tissue samples, athymic "nude" mouse experiments and cell-culture studies and probing enzyme interactions with small interfering RNA, the scientists determined that Akt2 was critical to the survival of colorectal cancer cells in the late stages of the dangerous process of metastasis— the development of secondary tumors at a distance from a primary tumor. At the same time, they also mapped the enzyme's interactions with other important proteins involved in colorectal cancer metastasis, laying the groundwork for the development of new therapies to stop the cancer's spread.

"Metastasis is a really complicated process," said Dr. Piotr G. Rychahou, lead author of the paper and an instructor in the UTMB department of surgery. "Through a complex cascade of events, cancer cells escape from the original tumor and invade surrounding tissues until they reach a blood or lymphatic vessel. Next, they cross the wall of the vessel and enter the circulation in order to reach a target organ—again crossing through the vessel wall —and grow into secondary tumors that we actually detect in patients. To survive this hazardous solo journey, invade a foreign organ and proliferate there, cancer cells need support from intracellular survival pathways. Akt2 is part of the PI3-kinase / Akt pathway, one of the strongest pro-survival signaling pathways."

Rychahou and his colleagues, including senior author and director of the UTMB Sealy Center for Cancer Cell Biology Dr. B. Mark Evers, suspected from previous work that Akt2 was significant in colorectal cancer metastasis. To profile the enzyme's involvement in metastasis, they started at the end of the metastatic road: examining tumor samples from patients with metastatic colorectal cancer and confirming that high levels of the enzyme were present.

Next, they conducted a series of experiments with athymic "nude" mice (mice bred to lack an immune response), injecting them with different colorectal cancer cell lines and using custom-designed siRNA treatments to decrease and increase the activity of Akt2, its relative Akt1 and the tumor-suppressing protein PTEN.

"When we decreased the Akt2 expression, we found there was really a significant difference," Rychahou said. "Akt2 is essential for the later stages of colon tumor metastasis, but we also found that increased Akt2 alone is not enough for the growth of secondary tumors. For that, you need continuous PI3-kinase pathway stimulation and activation which can occur with absence of PTEN in these tumors."

Discoveries such as these, according to Evers, are "crucial to providing more directed therapies for the treatment of colorectal cancer metastasis based upon inhibition of specific components of the PI3-kinase pathway, thus allowing for a more personalized treatment regimen with potentially fewer side effects"

Marsha Canright | EurekAlert!
Further information:
http://www.utmb.edu

More articles from Health and Medicine:

nachricht Cystic fibrosis alters the structure of mucus in airways
28.06.2017 | University of Iowa Health Care

nachricht Mice provide insight into genetics of autism spectrum disorders
28.06.2017 | University of California - Davis

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: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Supersensitive through quantum entanglement

28.06.2017 | Physics and Astronomy

X-ray photoelectron spectroscopy under real ambient pressure conditions

28.06.2017 | Physics and Astronomy

Mice provide insight into genetics of autism spectrum disorders

28.06.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>