A protein makes the difference

October 18, 2016

When tumours develop they absorb oxygen and nutrients from the surrounding tissue. Once the tumour reaches a certain size, this is no longer enough to allow it to continue growing. It needs new blood vessels to deliver oxygen and nutrients. A common form of cancer therapy involves inhibiting angiogenesis, or the development of new blood vessels. However, this therapy does not work for all patients and the reasons were not known for a long time.

To solve this mystery, a team led by PD Dr. Elisabeth Naschberger and doctoral candidate Andrea Liebl from the Professorship for Molecular and Experimental Surgery at the Department of Surgery at Universitätsklinikum Erlangen investigated endothelial cells, the cells which form blood vessels. They suspected that endothelial cells in different tumours have different characteristics and thus react differently to therapy.

The researchers began by isolating endothelial cells from intestinal tumours from patients with both good and poor prognoses and then compared the cells in cultures. They found that the endothelial cells from tumours of patients with a good prognosis produced the protein SPARCL1 - and that SPARCL1 inhibits the growth of both endothelial cells and tumour cells.

Further analysis of tissue samples revealed that SPARCL1 stabilises mature blood vessels in healthy intestinal tissue, thus inhibiting the formation of new blood vessels. SPARCL1 was found in tumours with good prognoses. In contrast the protein was deactivated in tumours with poor prognoses; in these cases new blood vessels were formed and the tumours continued to grow. The researchers refuted the dominant opinion with their results: 'Previously the assumption was that blood vessels always benefit tumour growth. However, we have shown that blood vessels, if they contain the protein SPARCL1, can also stem tumour growth,' explains Prof. Dr. Dr. Michael Stürzl, Professor of Molecular and Experimental Surgery.

'The study also shows why tumours in many cases continue to grow despite therapy intended to inhibit blood vessels,' adds Stürzl. 'In tumours whose blood vessels produce SPARCL1 and which are already adequately supplied with oxygen and nutrients, suppression of the blood vessels could foster tumour growth. It's important to note that the study does not recommend that antiangiogenic therapy not be used, but rather explains why such therapies may not be effective in all patients.' The researchers' next step is to work on developing the results for eventual use in cancer treatments.
-end-
The project received funding from the Interdisciplinary Centre for Clinical Research at Universitätsklinikum Erlangen, Deutsche Krebshilfe, the German Research Foundation and the Emerging Fields Initiative at FAU.

University of Erlangen-Nuremberg

Related Blood Vessels Articles from Brightsurf:

Biofriendly protocells pump up blood vessels
In a new study published today in Nature Chemistry, Professor Stephen Mann and Dr Mei Li from Bristol's School of Chemistry, together with Associate Professor Jianbo Liu and colleagues at Hunan University and Central South University in China, prepared synthetic protocells coated in red blood cell fragments for use as nitric oxide generating bio-bots within blood vessels.

Specific and rapid expansion of blood vessels
Upon a heart infarct or stroke, rapid restoration of blood flow, and oxygen delivery to the hypo perfused regions is of eminent importance to prevent further damage to heart or brain.

Flexible and biodegradable electronic blood vessels
Researchers in China and Switzerland have developed electronic blood vessels that can be actively tuned to address subtle changes in the body after implantation.

Lumpy proteins stiffen blood vessels of the brain
Deposits of a protein called ''Medin'', which manifest in virtually all older adults, reduce the elasticity of blood vessels during aging and hence may be a risk factor for vascular dementia.

Cancer cells take over blood vessels to spread
In laboratory studies, Johns Hopkins Kimmel Cancer Center and Johns Hopkins University researchers observed a key step in how cancer cells may spread from a primary tumor to a distant site within the body, a process known as metastasis.

Novel function of platelets in tumor blood vessels found
Scientists at Uppsala University have discovered a hitherto unknown function of blood platelets in cancer.

Blood vessels can make you fat, and yet fit
IBS scientists have reported Angiopoietin-2 (Angpt2) as a key driver that inhibits the accumulation of potbellies by enabling the proper transport of fatty acid into general circulation in blood vessels, thus preventing insulin resistance.

Brothers in arms: The brain and its blood vessels
The brain and its surrounding blood vessels exist in a close relationship.

Feeling the pressure: How blood vessels sense their environment
Researchers from the University of Tsukuba discovered that Thbs1 is a key extracellular mediator of mechanotransduction upon mechanical stress.

Human textiles to repair blood vessels
As the leading cause of mortality worldwide, cardiovascular diseases claim over 17 million lives each year, according to World Health Organization estimates.

Read More: Blood Vessels News and Blood Vessels Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.