Innovative method to starve tumors

Feb 11, 2009

The development of cancerous tumours is highly dependent on the nutrients the tumours receive through the blood. The team of Dr. Janusz Rak, of the Research Institute of the McGill University Health Centre (MUHC) at the Montreal Children's Hospital, including Dr. Khalid Al-Nedawi and Brian Meehan, has just discovered a new mechanism that tumours use to stimulate the growth of the blood vessels that feed them.

The researchers have also proposed a new way to control this process, which may translate into future therapies. These findings were published this week in the Proceedings of the National Academy of Sciences (PNAS).

An innovative method…

According to the researchers, tumour cells can release "bubbles" called microvesicles, which allow the tumours to communicate with the endothelial cells of blood vessels and stimulate changes in their behaviour. The microvesicles are armed with specific cancer proteins as they leave the tumour. When they are taken up by endothelial cells, the specific cancer proteins that they carry can trigger mechanisms that promote the abnormal formation of new blood vessels. The vessels then grow towards the tumour and supply it with the nutrients it requires to grow.

"We had already demonstrated the existence of these vesicles as well as their importance in the communication process between cancer cells and their environment. But this new discovery is much more targeted and represents a new direction in terms of therapy," said a delighted Dr. Rak.

… to starve tumors

In fact, a family of molecules derived from annexin V seems to effectively fight this process and ultimately may help "starve" the tumour. "The molecule we used is effective both in vitro and in vivo. It prevents the formation of new blood vessels in mice with cancer and therefore strongly inhibits tumour growth," explained Dr. Rak.

Called Diannexin, this molecule acts to block the in vitro fusion of vesicles and endothelial cells. In mice with cancer, Diannexin works to slow blood vessel growth towards the tumour, resulting in anti-cancer effects. This finding is particularly important considering the treatment was applied in isolation without additional chemotherapy. If combined with other agents, this new way of treating cancer may be even more potent.

Diannexin is currently being developed as an antithrombotic medication. It would therefore be possible to use it safely for different types of pathologies.

Source: McGill University Health Centre

Explore further: Quality of biopsy directly linked to survival in bladder cancer patients

add to favorites email to friend print save as pdf

Related Stories

Google profit dips to $2.8 bn

6 hours ago

Google said Thursday its profit in the past quarter dipped slightly from a year earlier, even as revenues for the technology giant showed a sharp increase.

Shrinking resource margins in Sahel region of Africa

6 hours ago

The need for food, animal feed and fuel in the Sahel belt is growing year on year, but supply is not increasing at the same rate. New figures from 22 countries indicate falling availability of resources per ...

Recommended for you

Fecal blood test may save more lives than colonoscopy

2 hours ago

State public health programs could screen many more low-income and uninsured people for colorectal cancer – and save up to four times as many lives – by using stool sample blood tests instead of colonoscopies, ...

Scientists discover hidden subpopulation of melanoma cells

7 hours ago

UNC School of Medicine researchers have pinpointed a set of intriguing characteristics in a previously unknown subpopulation of melanoma cancer cells in blood vessels of tumors. These cells, which mimic non-cancerous ...

User comments : 1

Adjust slider to filter visible comments by rank

Display comments: newest first

E_L_Earnhardt
not rated yet Feb 11, 2009
I suspect the "bubbles" contribute to the COOLING of the cells. CELLS DON'T EAT! They have no digestive system! What they receive by circulation is chiefly ENERGY! I suspect the use of inert gas in your bubbles would work even better!! Please try it!