Featured Research

from universities, journals, and other organizations

Genetic Program Builds The Pipeline That Nourishes Tumor Growth

Date:
August 21, 2000
Source:
Howard Hughes Medical Institute
Summary:
Detailed analysis of the activity levels of thousands of genes from blood vessel cells isolated from normal and cancerous tissue has led to the identification of a genetic program that constructs the pipeline that supplies blood and nutrients to colorectal tumors.

August 18, 2000 — Detailed analysis of the activity levels of thousands of genes from blood vessel cells isolated from normal and cancerous tissue has led to the identification of a genetic program that constructs the pipeline that supplies blood and nutrients to colorectal tumors.

Related Articles


Although the research was done primarily in cells derived from patients with colorectal cancer, the researchers believe that this genetic script may be a common one that runs when tumors need to supply themselves with the factors needed to sustain growth. The findings were reported in the August 18, 2000, issue of the journal Science by a research team that included Howard Hughes Medical Institute investigator Bert Vogelstein, Kenneth Kinzler and Brad St. Croix, who are at The Johns Hopkins University Oncology Center. The Hopkins team collaborated on the research with scientists from Duke University Medical Center.

"For close to twenty years we have been studying primary tumors from patients," said Vogelstein. "What’s new is that we are now studying the non-neoplastic, or non-cancerous, components—in this case the endothelial cells on which tumors depend for their blood supply and nutrients. The idea that these cells are critical to tumor growth was first suggested by Judah Folkman at Harvard," said Vogelstein.

The researchers started their studies by purifying endothelial cells from normal and cancerous tissue of patients. The researchers next analyzed the amount of messenger RNAs (mRNAs) produced by genes expressed in endothelial cells. The mRNA level of each gene gives the researchers a good estimate of the activity of each gene.

The scientists used SAGE (serial analysis of gene expression), a technique they invented to determine the activity level of genes. In SAGE, the enzyme, reverse transcriptase, is used to produce complementary DNA from the mRNA derived from cells under study. The DNA is then snipped at a defined position, creating a unique identifier "tag" that corresponds to a single gene. The researchers can then analyze the number of unique tags present in their sample and deduce how much mRNA exists for each gene.

The researchers generated about 100,000 tags from endothelial cells in normal and cancerous tissue. These tags corresponded to more than 32,500 unique mRNA transcripts. Many endothelial cell genes showed unique patterns of activity in one or the other type of tissue. The researchers were intrigued by a group of 46 genes, which they called tumor endothelial markers (TEMs), because these genes were elevated tenfold or more in tumor endothelium.

"We were really surprised at the number of differences we found," said Vogelstein. "And, we were delighted in the sense that many of these 46 genes can now become reasonable targets both for research and perhaps for new diagnostics and therapeutics."

The researchers found that at least seven of the 46 genes appear to be involved in forming or extending the scaffolding that cells use in creating new blood vessels. Thus, these genes are likely to be necessary for the growth of new blood vessels produced by tumors, said Vogelstein.

To validate that these genes were, indeed, activated in other types of cancer, the researchers measured the activity of nine of the genes in two other patients with different forms of cancer—finding, again, that these genes were expressed in high levels in tumor cells, but not in normal cells.

The activity levels of a select group of TEMs in cancers of the bone, liver, lungs, pancreas and brain were significantly higher than the activity levels of those genes in normal endothelial cells. "This a very promising finding because it means that if these genes become therapeutic targets, for example, by creating antibodies against their proteins, those antibodies would not only be potentially useful for colon cancers, but probably for most cancers," said Vogelstein.


Story Source:

The above story is based on materials provided by Howard Hughes Medical Institute. Note: Materials may be edited for content and length.


Cite This Page:

Howard Hughes Medical Institute. "Genetic Program Builds The Pipeline That Nourishes Tumor Growth." ScienceDaily. ScienceDaily, 21 August 2000. <www.sciencedaily.com/releases/2000/08/000821075124.htm>.
Howard Hughes Medical Institute. (2000, August 21). Genetic Program Builds The Pipeline That Nourishes Tumor Growth. ScienceDaily. Retrieved October 25, 2014 from www.sciencedaily.com/releases/2000/08/000821075124.htm
Howard Hughes Medical Institute. "Genetic Program Builds The Pipeline That Nourishes Tumor Growth." ScienceDaily. www.sciencedaily.com/releases/2000/08/000821075124.htm (accessed October 25, 2014).

Share This



More Health & Medicine News

Saturday, October 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

IKEA Desk Converts From Standing to Sitting With One Button

IKEA Desk Converts From Standing to Sitting With One Button

Buzz60 (Oct. 24, 2014) IKEA is out with a new convertible desk that can convert from a sitting desk to a standing one with just the push of a button. Jen Markham explains. Video provided by Buzz60
Powered by NewsLook.com
Ebola Protective Suits Being Made in China

Ebola Protective Suits Being Made in China

AFP (Oct. 24, 2014) A factory in China is busy making Ebola protective suits for healthcare workers and others fighting the spread of the virus. Duration: 00:38 Video provided by AFP
Powered by NewsLook.com
WHO: Millions of Ebola Vaccine Doses by 2015

WHO: Millions of Ebola Vaccine Doses by 2015

AP (Oct. 24, 2014) The World Health Organization said on Friday that millions of doses of two experimental Ebola vaccines could be ready for use in 2015 and five more experimental vaccines would start being tested in March. (Oct. 24) Video provided by AP
Powered by NewsLook.com
Doctor in NYC Quarantined With Ebola

Doctor in NYC Quarantined With Ebola

AP (Oct. 24, 2014) An emergency room doctor who recently returned to the city after treating Ebola patients in West Africa has tested positive for the virus. He's quarantined in a hospital. (Oct. 24) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins