Navigation Links
Potent metastasis inhibitor identified
Date:6/22/2009

Researchers at Children's Hospital Boston have isolated a potent inhibitor of tumor metastasis made by tumor cells, one that could potentially be harnessed as a cancer treatment. Their findings were published in the online Early Edition of the Proceedings of the National Academy of Sciences during the week of June 22.

Metastasisthe migration of cancer cells to other parts of the bodyis one of the leading causes of death from cancer, and there is no approved therapy for inhibiting or treating metastases. Randoph S. Watnick, PhD, an assistant professor in the Vascular Biology Program at Children's, has been finding that metastatic tumors prepare landing places in distant organs for their metastases, by secreting certain proteins that encourage tumor growth and attract feeder blood vessels. Now, he and his colleagues show that non-metastatic tumors secrete a protein called prosaposin -- which inhibits metastasis by causing production of factors that block the growth of blood vessels.

Cells from localized prostate and breast tumors, which didn't metastasize, secreted high levels of prosaposin, they found, while metastatic tumors secreted very little. When the researchers injected mice with tumor cells that were known to be highly metastatic, but to which they had added prosaposin, lung metastases were reduced by 80 percent and lymph node metastases were completely eliminated, and survival time was significantly increased. Conversely, when they suppressed prosaposin expression in tumor cells, they saw more metastases.

When prosaposin was directly injected into mice that had also received an injection of tumor cells, the tumor cells formed virtually no metastases in the lung, or, if they did, formed much smaller colonies. These mice lived at least 30 percent longer than mice not receiving prosaposin.

Watnick and colleagues also demonstrated that prosaposin stimulates activity of the well-known tumor suppressor p53 in the connective tissue (stroma) surrounding the tumor. This in turn stimulated production of thrombospondin-1, a natural inhibitor of blood vessel growth (angiogenesis), both in the tumor stroma and in cells at the distant location.

"Prosaposin, or derivatives that stimulate p53 activity in a similar manner in the tumor stroma, might be an effective way to inhibit the metastatic process in humans," says Watnick.

If this bears out, Watnick envisions treating cancer patients for their primary tumor, and concurrently giving them drugs to prevent metastases or slow their growth. "While we may not be able to keep patients from getting cancer, we can potentially keep them metastasis-free," he says.

Initially, Watnick's scientific interest was focused on metastatic cancer cells; he hoped to use proteomics techniques to isolate different proteins that steered metastases to different parts of the body (explaining, for example, why lung cancer often metastasizes to bone, or prostate cancer to liver). But the late Judah Folkman, MD, founder of the Vascular Biology program at Children's, encouraged him to focus on the metastasis inhibitor -- prosaposin. "You might have a drug right here," he told Watnick.

A patent has been filed by Children's Hospital Boston on the discovery. The hospital's Technology and Innovation Development Office is in active discussions to license prosaposin for commercial development.


'/>"/>

Contact: Bess Andrews
elizabeth.andrews@childrens.harvard.edu
617-919-3110
Children's Hospital Boston
Source:Eurekalert

Related medicine news :

1. DNA vaccine against multiple sclerosis appears safe, potentially beneficial
2. UCLA study identifies designer estrogen as potential MS drug
3. Office-Based Medical Treatment and Internet Resources Are Potential Solution to Rising Painkiller Misuse Among Teens, Young Adults
4. Common abdominal pain may be due to a potentially treatable newly recognized inflammatory reaction
5. Potential new approach to treat cognitive impairments in schizophrenia
6. Nosespray vaccine using aloe vera has exciting potential, researcher says
7. Network approach identifies potential breast cancer susceptibility gene
8. Potent peptides inhibit HIV entry into cells
9. Liver fibrosis will be treated by a potential target
10. Researchers study potential health benefits of natural chemicals in muscadine grape seeds
11. Jefferson researchers find stem cells in degenerating spinal discs, potential for repair
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:8/23/2017)... ... August 23, 2017 , ... This week the The Voss Law Firm celebrates ... Bill Voss, the firm grew quickly and has built a reputation for excellence, trust, ... get the money they deserve from their insurance companies. , The Voss Law ...
(Date:8/23/2017)... ... August 23, 2017 , ... Earlier this month, the Workgroup for ... health IT to create efficiencies in healthcare information exchange and a trusted advisor to ... Forum which featured keynote addresses by Donald W. Rucker, MD, head of the ...
(Date:8/23/2017)... ... 23, 2017 , ... The Stevie® Awards have announced the winners of the Best of the ... business awards competition. , Nominees in the 2017 IBAs were not able to apply for ... on the total number of awards won in the IBAs with a Gold Stevie win ...
(Date:8/23/2017)... Lauderdale, FL (PRWEB) , ... August 23, 2017 ... ... firms for traveling medical professionals, recently launched a new website, http://www.cirrusmedicalstaffing.com . ... built to respond to the needs of healthcare professionals who are traveling on ...
(Date:8/23/2017)... ... August 23, 2017 , ... ... has been named to the 2017 Inc. 500|5000, an exclusive ranking of America’s ... growth rate of 139 percent, marking the twelfth year that the company has ...
Breaking Medicine News(10 mins):
(Date:8/14/2017)... N.J. and PETACH TIKVAH, Israel ... Inc. (NASDAQ: BCLI), a leading developer of adult stem ... the second quarter ending June 30, 2017. ... stages of preparing for our pivotal Phase 3 trial ... Chaim Lebovits , President and Chief Executive Officer of ...
(Date:8/10/2017)... 2017  Physical Rehabilitation Network (PRN), acquired the long-standing outpatient ... Colorado . The reputable clinic will continue to be ... with his staff of four clinicians. Lipkin received his doctorate ... over 10 years of experience with a strong background in ... marks the 10th PRN clinic in and around the ...
(Date:8/8/2017)... Second-quarter 2017 revenues of $876 million ... continuing operations Second-quarter 2017 ... million Second-quarter 2017 Sterile ... Second-quarter 2017 adjusted diluted earnings ... to $0.93 Second-quarter 2017 ...
Breaking Medicine Technology: