Navigation Links
Study identifies another strategy for normalizing tumor blood supply
Date:2/20/2008

Manipulating levels of nitric oxide (NO), a gas involved in many biological processes, may improve the disorganized network of blood vessels supplying tumors, potentially improving the effectiveness of radiation and chemotherapy. In an upcoming issue of the journal Nature Medicine, researchers from the Steele Laboratory of Radiation Oncology at Massachusetts General Hospital (MGH) report an experiment in which NO production was selectively suppressed in tumor cells while being maintained in blood vessels. The result was a significant improvement in the appearance and function of the tumors blood supply.

Our finding suggest that the creation of perivascular NO gradients differences between the levels produced in blood vessels and those found in tumor tissue may be able to normalize tumor vasculature, says Dai Fukumura, MD, PhD, of the Steele Laboratory, who led the study. Combining the use of angiogenesis inhibitors, which normalize vasculature through a different mechanism, with the blockade of nonvascular NO production may produce even greater improvement in therapeutic outcomes.

The blood vessels that develop around and within tumors are leaky and disorganized, interfering with delivery of chemotherapy drugs and with radiation treatment, which requires an adequate oxygen supply. Combining angiogenesis inhibitors, drugs that suppress the growth of blood vessels, with traditional anticancer therapies has improved patient survival in some tumors. That success supports a theory developed by Rakesh K. Jain, PhD, director of the Steele Laboratory, that the agents temporarily normalize blood vessels, creating a period during which other treatments can be more effective.

Since angiogenesis is one of many physiologic activities mediated by NO, the MGH research team hypothesized that restricting NO production to blood vessels also could improve tumor vasculature. Using cancer cells from human brain tumors, they suppressed the enzyme that controls NO production in nonvascular tissue. When the modified tumor cells were implanted into mice, analysis of the resulting tumors showed that NO was present primarily in blood vessels, with significant reductions in tumor cells. Vessels in the growing tumors were more evenly distributed and less distorted than those in tumors grown from untreated tissue.

Angiogenesis inhibitors block formation of new vessels by directly or indirectly inhibiting the proliferation and survival of vascular endothelial cells. But since their overall effect is to reduce the density of blood vessels, the ability of those agents to normalize tumor vasculature may not last long, says Fukumura. Blocking nonvascular NO production and maintaining NO levels around the vessels appears to keep endothelial cell function at the proper level. An associate professor of Radiation Oncology at Harvard Medical School, Fukumura notes that the strategy now should be investigated in other types of tumors.


'/>"/>

Contact: Sue McGreevey
smcgreevey@partners.org
617-724-2764
Massachusetts General Hospital
Source:Eurekalert

Related medicine news :

1. Grant to study if early BPA exposure leads to late prostate cancer
2. Mailman School PH study finds increase in thyroid diseases risk from exposure at Chernobyl
3. Study: low-income women more likely to suffer from postpartum depression
4. Study Shows New Therapy Opens Blocked Fallopian Tubes, Returns Fertility Without Surgery
5. Study suggests antibiotic may prevent dreaded brain fever
6. Study: Before a CT scan or angiogram, many people should take inexpensive drug to protect kidneys
7. Study Suggests Glucosamine Wont Ease Hip Arthritis
8. Scientists using laser light to detect potential diseases via breath samples, says new study
9. Major study links insurance status to advanced stage in multiple cancers
10. 7-year neck pain study sheds light on best care
11. PLC Systems Files IDE Supplement to Begin Pivotal Study of RenalGuard(TM) and Provides Update on Planned Development Timeline
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/28/2017)... ... April 28, 2017 , ... Datta Endoscopic Back ... joined the revolutionary endoscopic practice under Dr. Datta. Patel is a Board Certified ... The patented, revolutionary eDiscSculpt Technique created and used by Datta Endoscopic is unlike ...
(Date:4/28/2017)... ... April 28, 2017 , ... From April ... of Urgent Care Medicine will host industry leaders for the annual spring Convention ... those in the industry adapt to the issues currently affecting urgent care and ...
(Date:4/28/2017)... ... ... Bill Howe started his sewer and drain company in 1980 focusing heavily ... team, the Bill Howe brand was born and they began cultivating their mission to ... the San Diego community in which they worked, lived and were raising their daughters. ...
(Date:4/28/2017)... ... April 28, 2017 , ... ... North East region. Côté has 20+ years of experience within the beauty industry, ... worked with an array of high-end cosmetic brands, retail brands and outlets in ...
(Date:4/28/2017)... ... April 28, 2017 , ... NuevaCare, a leading home care agency based ... and Palo Alto, is proud to announce information upgrades to its blog in the ... organized content on topics such as home care (generally) as well as senior care ...
Breaking Medicine News(10 mins):
(Date:4/20/2017)... Sweden , April 20, 2017 ... NEVPF) ("NeuroVive") today announced positive preclinical results ... preclinical compound for non-alcoholic steatohepatitis (NASH), in ... NV556 has previously shown ... NASH model. Today, NeuroVive,s scientists present novel ...
(Date:4/19/2017)... Cardiology devices segment is anticipated to reach the highest market ... segment is likely to create absolute $ opportunity of a ... By the end of 2027, Cardiology Devices segment is projected ... expanding at a CAGR of 18.4% over the forecast period. ... reprocessed medical devices market in terms of revenue ...
(Date:4/19/2017)... 19, 2017 Global Surgical Drainage Device Market: ... used to remove excess liquid and air. The fluid ... bile or lymph. Surgical drains are used in a ... orthopedics surgery, cardiovascular surgery, neurosurgery, plastic surgery etc. Common ... prevent accumulation of fluid e.g. blood or pus. Surgical ...
Breaking Medicine Technology: