Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Missing Receptor Molecule Causes Tumor Growth

16.06.2005


A missing receptor molecule contributes to the growth of tumors in human ovaries. This surprisingly evident connection has now been proven by a team at the Medical University of Vienna, who published their data in the science journal Molecular Cancer Research. The team, who is supported by funding from the Austrian Science Fund FWF, also discovered the possible genetic reason why the receptor molecule, which is an important factor in regulating cell growth, is missing.


Immunohistochemistry shows the down regulation of DR4 receptor molecules in an affected tumor (A) where the cells have lost their capacity to undergo apoptosis compared to an unaffected tumor sample (B).



In healthy tissue, cells grow and divide - this is also true of cancerous tumors. The difference between the two lies in the regulation, which functions well in healthy tissue, but not in tumors. An important mechanism of this regulation is programmed cell death, known as apoptosis. It causes the controlled death of single cells, if this is to the advantage of the whole organism. If this process of self-protection does not work then the destructive cells can proliferate uncontrollably.

Signal Without Effect


Prof. Michael Krainer and his team from the Medical University of Vienna have now been able to prove that programmed cell death does not function in cells of certain tumors in the ovaries. Not because the starting signal is missing, but because this signal cannot be received by the cell.

This finding, published today in the American science journal Molecular Cancer Research, shows that these cells lack a receptor molecule called DR4. DR4 is responsible for receiving the signal molecule TRAIL, which initiates apoptosis in these cells.

Prof. Krainer explains: "To begin with it was not evident what was missing in the signal transmission. The signal or the receptor molecule? To answer this question, we examined ten different ovarian cancer cell lines. In doing this we found out that 40% of these specimens contained none or only a few DR4 receptor molecules." It was proven in further tests that these cells react particularly badly to TRAIL. This proves that the missing receptor and not the missing signal can contribute significantly to tumor growth.

Silenced Genes

Further tests proved why there was such a small number of receptors. Prof. Krainer: "There can be two reasons for the loss of a receptor molecule like DR4. Firstly, the responsible gene could have been lost or damaged. Secondly, this gene could have been modified in a way which would prevent it from functioning." It was exactly the latter. Prof. Krainer and his team ascertained that in 75% of the specimens which contained only a few DR4 receptors the responsible gene was modified. Some components of this gene were modified by attaching methyl groups. Methylation is indeed a common way in which cells silence genes, but in the affected tumor cells, it obviously happens at the wrong time.

To conclude their research, Prof. Krainer and his colleagues retested their findings: Their results were confirmed by testing 36 different tumor tissues taken directly from patients. In comparison, these cells represent the real causes of disease much better than cell cultures commonly used for experimental research. It was determined that in 20% of the tissues examined the gene responsible for DR4 was methylated to a higher degree and DR4 was missing.

This research supported by funding from the Austrian Science Fund, FWF, paves the way for future therapy through the important discovery that the methylation of the gene for DR4 can contribute to the formation of tumors. These therapies could manipulate the malfunctioning signal transfer system, DR4-TRAIL, to make cancer cells return to the originally programmed cell death.

Till C. Jelitto | alfa
Further information:
http://www.fwf.ac.at/en/press/receptor.html

More articles from Life Sciences:

nachricht Discovery of a Key Regulatory Gene in Cardiac Valve Formation
24.05.2017 | Universität Basel

nachricht Carcinogenic soot particles from GDI engines
24.05.2017 | Empa - Eidgenössische Materialprüfungs- und Forschungsanstalt

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

Im Focus: Using graphene to create quantum bits

In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits -- or qubits -- that are stable, meaning they are not much affected by changes in their environment. This normally needs highly nonlinear non-dissipative elements capable of functioning at very low temperatures.

In pursuit of this goal, researchers at EPFL's Laboratory of Photonics and Quantum Measurements LPQM (STI/SB), have investigated a nonlinear graphene-based...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

Physicists discover mechanism behind granular capillary effect

24.05.2017 | Physics and Astronomy

Measured for the first time: Direction of light waves changed by quantum effect

24.05.2017 | Physics and Astronomy

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>