Navigation Links
Cancer cells spread by releasing 'bubbles', according to an MUHC study
Date:4/21/2008

This release is available in French.

Montreal, April 21, 2008 A new fundamental mechanism of how tumour cells communicate has just been discovered by the team of Dr. Janusz Rak at the Research Institute of the McGill University Health Centre (MUHC) in collaboration with Dr Guha from the University of Toronto. The cancer cells are able to communicate with their more healthy counter-parts by releasing vesicles. These bubble-like structures contain cancer-causing (oncogenic) proteins that can trigger specific mechanisms when they merge into non or less-malignant cells. These findings could change our view on how cancerous tissues work and lead to major clinical innovations. They were published on April 20 in the on-line edition of Nature Cell Biology.

The surface of some brain tumour cells has long been known to express a mutated version of what is called the variant III epidermal growth factor receptor (EGFRvIII). Although this factor is expressed only in a fraction of tumour cells, it has a major impact on the malignancy of the whole tumor. How could this cellular minority have such an important impact" This mechanism was still unknown until now.

This study shows that the mutated EGFRvIII triggers production of small vesicles that project from the cell membrane and that carry mutated copies of EGFRvIII on their surfaces. They were baptised oncosomes. Surprisingly enough, this shows that oncoproteins are not always confined to the cell that produced them. In this case they even migrate!

Oncosomes will migrate until they fuse with another cell, either healthy or benign tumoral. Oncogenic protein AGFRvIII then becomes integrated in the membrane of the recipient cell and starts stimulating specific metabolic pathways to make it act in an aberrant and malignant way. Although this may be a transient event, the changes could impact tumor behaviour by more rapid increases in cell numbers and by stimulation of blood vessel growth, hallmarks of malignant brain tumors.

With this information we can imagine that many mutant proteins are not necessarily confined to the cells that make them, but rather can migrate and spread around as cargo of oncosomes, a process that could be referred to as formation of the oncogenic field effect, explained Dr. Rak. It demonstrates that cancer is a multi-cell process, where the cells talk to one another extensively. This goes against the traditional view that a single mutated cell will simply multiply uncontrollably to the point of forming a tumour. This discovery opens exciting new research avenues, but we also hope that it will lead to positive outcomes for patients.

Indeed, the presence of oncosomes (containing EGFRvIII or other proteins) in blood of cancer patients could become a clinical marker, meaning that doctors could screen for a tumours molecular characteristics instead of having to perform invasive surgery or biopsy. Currently, in the case of brain cancer, this very precise assessment cannot be performed without removing the tumour and therefore opening a patients skull. However, the assay and analysis of oncosomes would potentially only require taking a small sample of blood or cerebrospinal fluid. This would be a step in ensuring patient comfort and choosing the best therapeutic strategy for them, factors that are key in the journey towards personalized medicine in a hopefully not-too-distant future.


'/>"/>
Contact: Isabelle Kling
isabelle.kling@muhc.mcgill.ca
514-934-1934
McGill University Health Centre
Source:Eurekalert

Related medicine news :

1. Thousands of volunteers needed to help bring cure for cancer closer
2. Many Cancer Survivors Are Overweight and Sedentary: Study
3. Study reveals inaccuracies in studies of cancer treatment
4. Cancer survivors have low levels of physical activity and high levels of obesity
5. Obesity, inactivity as common among cancer survivors as rest of Canadians, study shows
6. Exercise Combats Cancer Fatigue
7. Dealing Cervical Cancer a Knockout Blow
8. Talk Therapy Proves Effective for Terminal Cancer Patients
9. Vitamin D and breast cancer risk
10. Study finds patients overestimate cancer screening history
11. Millions of Euros could be saved if breast cancer follow-ups were led by specialist nurses
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:5/26/2016)... Franklin, TN (PRWEB) , ... May 26, 2016 , ... ... today, and more than 32 million cancer survivors worldwide. On Sunday, June 5, 2016, ... the 29th annual National Cancer Survivors Day®. , National Cancer Survivors Day® is ...
(Date:5/26/2016)... ... ... In an effort to provide hair restoration information to the widest possible audience, Dr. Parsa ... not use the app. Dr. Mohebi, the founder of Parsa Mohebi Hair Restoration, is making ... , Dr. Mohebi says, “The positive response to the Snapchat videos we started last month ...
(Date:5/26/2016)... , ... May 26, 2016 , ... North Cypress ... 13 at Blackhorse Golf Club in Cypress. With the help of community partners, the ... restores, empowers, and renews hope for wounded service members and their families through health, ...
(Date:5/26/2016)... ... May 26, 2016 , ... ... products recently hosted the first PowerWave Instructor Certification Course in Stoughton, Massachusetts. The ... group of fitness professional through the 8 hour interactive course to qualify participants ...
(Date:5/26/2016)... ... May 26, 2016 , ... The introduction of our professional athletes coincides with ... ™”. , “We are proud to introduce Meghan Klingenberg, defender and World ... Brian Quick, wide receiver for Los Angeles who was a second round selection in ...
Breaking Medicine News(10 mins):
(Date:5/25/2016)... , May 25, 2016  Zymo Research Corp. ... their new reference materials that help researchers obtain ... collection to analyses. The rapid growth of the ... researchers to have standard methods to improve the ... Biases inherently exist at every step of the ...
(Date:5/25/2016)... According to market research "Global ... Demand Forecast to 2022 - Industry Insights by Type ... by P&S Market Research, the global insulin delivery device ... it is expected to grow at a CAGR of ... segment is expected to witness the fastest growth at ...
(Date:5/25/2016)... , May 25, 2016  Granger Diagnostics today ... test for wounds and infections. This test ensures ... and select viruses. The test requires only a ... David G. Bostwick , MD, ... to facilitate wound healing: "We are excited to ...
Breaking Medicine Technology: