Navigation Links
Synthetic compound promotes death of lung-cancer cells, tumors
Date:11/12/2007

DALLAS Nov. 12, 2007 Human lung-cancer tumors grown in mice have been shown to regress or disappear when treated with a synthetic compound that mimics the action of a naturally occurring death-promoting protein found in cells, researchers at UT Southwestern Medical Center report.

The findings, appearing in todays issue of Cancer Cell, suggest that the compound might one day be used in targeted therapies for lung and possibly other cancers, the researchers said.

We found that certain kinds of lung-cancer cells were sensitive to this compound, which sends a signal to cancer cells to self-destruct, said Dr. Xiaodong Wang, professor of biochemistry at UT Southwestern and senior author of the study.

In 2000, Dr. Wang announced the discovery of a cellular protein called Smac, which plays a key role in the normal self-destruction apparatus present in every cell. This process, called apoptosis, is activated when a cell needs to be terminated, such as when a cell is defective or becomes unnecessary during normal growth and development. In cancer cells, the self-destruct mechanism is faulty.

In 2004, Dr. Wang and his colleagues developed a compound that mimics the action of Smac. They found that in cell cultures, the compound killed cancer cells but left healthy cells unaffected. In those studies, however, the Smac mimic only killed cancer cells when it was introduced along with another molecule often involved in the cell-death machinery, called tumor necrosis factor-a, or TNFa.

In the current study, Dr. Wangs research group tested 50 human non-small-cell lung-cancer cell lines in culture and found that 22 percent of them were sensitive to the Smac mimic alone, without having to add TNFa. The researchers also found that the Smac mimic alone was effective against some types of breast cancer and melanoma cells in culture.

The apparent ability of a Smac mimetic, as a single agent, to induce cell death in nearly one-quarter of lung-cancer cell lines tested was quite remarkable, said Dr. Wang, who is a Howard Hughes Medical Institute investigator at UT Southwestern.

The researchers then introduced those sensitive cancer-cell lines into mice, where they grew into tumors. When the lung-tumor-bearing mice were injected with the Smac mimic, the tumors reduced significantly in size, and in some cases, the tumors disappeared completely.

Also tried was a similar experiment treating breast-cancer tumors in mice with the Smac mimic alone. That treatment, however, showed little effect.

The researchers then investigated what made those particular lung-cancer cell lines so sensitive to the Smac mimic alone.

We found that these sensitive cell lines produce their own TNFa, Dr. Wang said.

In addition to aiding in cell death, TNFa also is known, paradoxically, to sometimes play a role in aiding cancer-cell survival and growth. In combination with the Smac mimic, however, the role of this molecule is clear: cell death.

The Smac mimetic is able to exploit certain cancer cells that secrete TNFa and usurp this pro-survival signal to promote cell death, Dr. Wang said.

Not only is single-agent Smac mimetic treatment highly effective at inducing cell death in these cell lines, but it also offers the possibility of highly specific and relatively nontoxic future therapeutic treatments by exploiting certain cancer cells own production of TNFa.

Additional research and tests will be needed before the Smac mimic is tested in humans, Dr. Wang said, adding that detecting the presence of TNFa in a patient could serve as a marker to indicate that the cancer might be sensitive to treatment with the Smac mimic alone.

The challenge for cancer therapies now is that they also tend to kill normally growing cells as well as cancer cells, which results in undesirable side effects, he said. Because this compound affects cancer cells selectively, it could combat this problem.


'/>"/>

Contact: Amanda Siegfried
amanda.siegfried@utsouthwestern.edu
214-648-3404
UT Southwestern Medical Center  
Source:Eurekalert

Related biology news :

1. Chloroplast f and m Thioredoxins Discovered in Nonphotosynthetic Tissues
2. New microsensor measures volatile organic compounds in water and air on-site
3. Naturally-occurring apple compounds reduce risk of pancreatic cancer
4. Chemical compound present in detergents produce bacteria alterations in agricultural soils
5. Bleeding, not inflammation, is major cause of early lung infection death
6. Small-scale fishing in Mexico rivals industrial fisheries in accidental turtle deaths
7. Scientists find how amber becomes death trap for watery creatures
8. MIT develops tractor beam for cells, more
9. Invasion of the brain tumors
10. Analysis of breast and colon cancer genes finds many areas of differences between tumors
11. Cell response to stress signals predicts tumors in women with common pre-breast cancer
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Synthetic compound promotes death of lung-cancer cells, tumors
(Date:4/13/2017)... According to a new market research report "Consumer IAM Market by ... Service, Authentication Type, Deployment Mode, Vertical, and Region - Global Forecast to ... USD 14.30 Billion in 2017 to USD 31.75 Billion by 2022, at ... ... MarketsandMarkets Logo ...
(Date:4/11/2017)... Research and Markets has announced the addition ... their offering. ... tracking market to grow at a CAGR of 30.37% during the ... 2017-2021, has been prepared based on an in-depth market analysis with ... its growth prospects over the coming years. The report also includes ...
(Date:4/11/2017)... NXT-ID, Inc. (NASDAQ:   NXTD ) ("NXT-ID" or ... independent Directors Mr. Robin D. Richards and Mr. ... the company,s corporate governance and expertise. ... Gino Pereira , Chief Executive Officer said," ... and benefiting from their considerable expertise as we move forward ...
Breaking Biology News(10 mins):
(Date:4/27/2017)... and RESEARCH TRIANGLE PARK, N.C. ... (NASDAQ: UTHR ) today announced that its ... $250 million of the company,s common stock. This program ... December 31, 2017. Purchases may be made in the ... transactions from time to time as determined by United ...
(Date:4/27/2017)... ... April 27, 2017 , ... Mitotech S.A, a Luxembourg ... Hereditary Optic Neuropathy (LHON) patients. LHON is a rare devastating genetic disease that leads ... eye drops in a group of 20 patients carrying 11778, 14484 and 3460 mutations ...
(Date:4/27/2017)... Linda, Ca (PRWEB) , ... April 27, 2017 ... ... hear from a practicing internist, who will review how testing for 1,25-Dihydroxyvitamin D ... that prompt ordering of 25-OH-vitamin D and 1,25 dihydroxyvitamin D. , Dr. Gregory ...
(Date:4/27/2017)... ... April 27, 2017 , ... Volunteers supported by ... researchers, engineers, and industry professionals in visiting U.S. Congressional offices in Washington, D.C., ... the world photonics industry. , This year, National Photonics Initiative (NPI) ...
Breaking Biology Technology: