Featured Research

from universities, journals, and other organizations

Panel of melanoma mutations opens door to new treatment possibilities

Date:
November 18, 2011
Source:
American Association for Cancer Research
Summary:
Researchers have developed a new genetic screening tool that will aid in the investigation of possible treatments for patients with melanoma and the unique genetic mutations that may accompany the disease, according to new research.

Researchers have developed a new genetic screening tool that will aid in the investigation of possible treatments for patients with melanoma and the unique genetic mutations that may accompany the disease, according to data presented at the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics, held Nov. 12-16, 2011.

Heinz-Herbert Fiebig, M.D., Ph.D., associate professor of medical oncology at the University of Freiburg in Germany, presented data from 25 patient-derived melanoma models for which he and his colleagues studied relevant genetic mutations and the effect of new targeted and cytotoxic chemotherapeutic agents.

In this study, Fiebig, who is also the president and CEO of Oncotest GmbH Institute for Experimental Oncology, and colleagues collected melanoma samples from 80 patients. They were able to grow 38 of them in nude mice from which 25 permanent models were established. Eight different genetic mutations were determined in these models.

"The most prominent mutations were found in the BRAF oncogene; namely, 16 out of 25 tumors were positive for the mutation," said Fiebig.

About 25 percent of melanoma cases had a mutated NRAS gene. PI3Kalpha mutations were rare, and the screening found no mutations of the KRAS gene, which is a common genetic mutation in other forms of cancer.

The researchers then exposed the melanomas bearing specific mutations in vitro in the clonogenic assay to a variety of cancer treatments including traditional cytotoxic chemotherapy drugs, such as cisplatin, paclitaxel or vincristine, and modern chemotherapeutic drugs that target specific mutations, such as sorafenib and vemurafenib. They hoped to determine which, if any, of these drugs had an effect on the cancer cells and whether that effect was related to the presence or lack of a mutation.

The tests indicated that vemurafenib -- or PLX-4720 -- was most effective in melanoma tumor samples with the V600E mutation in the BRAF gene. This finding echoes those of recent clinical studies in humans. In addition, vincristine was found to only be effective in tumor samples that did not have a mutation in the BRAF gene. "Up until now, we were not able to detect other correlations between chemosensitivity against cytotoxic or targeted agents and other mutations," said Fiebig.

In the melanoma models, vemurafenib was 100 times more active in V600E-mutated melanomas compared with those melanomas with no mutations, Fiebig said. However, in the clinic, the majority of patients developed resistance within one year.

"Our melanoma models will allow researchers to investigate and overcome the possible underlying resistance mechanisms -- for example, by combining vemurafenib with other target-specific agents," Fiebig said. "In addition, other new targeted drugs are being studied in a systematic way."

The study was funded by Oncotest.


Story Source:

The above story is based on materials provided by American Association for Cancer Research. Note: Materials may be edited for content and length.


Cite This Page:

American Association for Cancer Research. "Panel of melanoma mutations opens door to new treatment possibilities." ScienceDaily. ScienceDaily, 18 November 2011. <www.sciencedaily.com/releases/2011/11/111115175633.htm>.
American Association for Cancer Research. (2011, November 18). Panel of melanoma mutations opens door to new treatment possibilities. ScienceDaily. Retrieved April 20, 2014 from www.sciencedaily.com/releases/2011/11/111115175633.htm
American Association for Cancer Research. "Panel of melanoma mutations opens door to new treatment possibilities." ScienceDaily. www.sciencedaily.com/releases/2011/11/111115175633.htm (accessed April 20, 2014).

Share This



More Health & Medicine News

Sunday, April 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Nine-Month-Old Baby Can't Open His Mouth

Nine-Month-Old Baby Can't Open His Mouth

Newsy (Apr. 19, 2014) Nine-month-old Wyatt Scott was born with a rare disorder called congenital trismus, which prevents him from opening his mouth. Video provided by Newsy
Powered by NewsLook.com
'Holy Grail' Of Weight Loss? New Find Could Be It

'Holy Grail' Of Weight Loss? New Find Could Be It

Newsy (Apr. 18, 2014) In a potential breakthrough for future obesity treatments, scientists have used MRI scans to pinpoint brown fat in a living adult for the first time. Video provided by Newsy
Powered by NewsLook.com
Little Progress Made In Fighting Food Poisoning, CDC Says

Little Progress Made In Fighting Food Poisoning, CDC Says

Newsy (Apr. 18, 2014) A new report shows rates of two foodborne infections increased in the U.S. in recent years, while salmonella actually dropped 9 percent. Video provided by Newsy
Powered by NewsLook.com
Scientists Create Stem Cells From Adult Skin Cells

Scientists Create Stem Cells From Adult Skin Cells

Newsy (Apr. 17, 2014) The breakthrough could mean a cure for some serious diseases and even the possibility of human cloning, but it's all still a way off. Video provided by Newsy
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:
from the past week

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