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:6/25/2016)... , ... June 25, 2016 , ... ... and non-athletes recover from injury. Recently, he has implemented orthobiologic procedures as a ... area —Johnson is one of the first doctors to perform the treatment. Orthobiologics ...
(Date:6/24/2016)... ... June 24, 2016 , ... Those who have experienced traumatic events ... turn to unhealthy avenues, such as drug or alcohol abuse, as a coping mechanism. ... tools for healthy coping following a traumatic event. , Trauma sufferers tend to feel ...
(Date:6/24/2016)... ... June 24, 2016 , ... Global law firm Greenberg Traurig, ... Elite. The attorneys chosen by their peers for this recognition are considered among the ... Traurig Shareholders received special honors as members of this year’s Legal Elite Hall of ...
(Date:6/24/2016)... ... June 24, 2016 , ... People across the U.S. are sharpening their ... Award, an essay contest in which patients and their families pay tribute to a ... the 2016 National Society of Genetic Counselors (NSGC) Annual Education Conference (AEC) this September. ...
(Date:6/24/2016)... Maryland (PRWEB) , ... June 24, 2016 , ... ... Angels is actively feeding the Frederick area economy by obtaining investment capital for ... over the past 2½ years that have already resulted in more than a ...
Breaking Medicine News(10 mins):
(Date:6/26/2016)... LAS VEGAS , June 26, 2016 ... movement to value-based care operating models within the health ... that enable greater financial efficiency , Deloitte offers ... address the key business issues impacting efficient cost optimization: ... alignment , These services facilitate better outcomes and ...
(Date:6/24/2016)... June 24, 2016 ... announced the addition of the " Global Markets ... This report focuses ... an updated review, including its applications in various applications. ... market, which includes three main industries: pharmaceutical and biotechnology, ...
(Date:6/24/2016)... , June 24, 2016 Research ... World Market for Companion Diagnostic Tests" report to their ... Market for Companion Diagnostics The World Market ... and personalized medicine diagnostics. Market analysis in the report includes ... Test Market (In Vitro Diagnostic Kits) by Region (N. America, ...
Breaking Medicine Technology: