Navigation Links
Panel of melanoma mutations opens door to new treatment possibilities

SAN FRANCISCO 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."


Contact: Jeremy Moore
American Association for Cancer Research

Related medicine news :

1. Panel asks dairy avoiders: Are you getting enough?
2. Avoiding Dairy Due to Lactose Intolerance is Unnecessary in Most Cases and May Pose Diet and Health Risks, Concludes National Institutes of Health Consensus Development Conference Panel
3. All Global Launches Physician Panels in Russia and Poland
4. Panel questions VBAC bans, advocates expanded delivery options for women
5. Panel Finds Many Women Can Avoid Repeat C-Sections
6. Panel: Properly designed pay-for-performance models can support medical professionalism
7. Panel: FCCs Broadband Plan Will Boost Efforts to Expand Health IT
8. FDA Panel Weighs New Restrictions on Tanning Beds
9. R. Shane Jackson Selected as Panelist for Center for Health Transformation Member Meeting
10. Review Panel Leaves Controversial Lyme Disease Guidelines Unchanged
11. HIA-LI 22nd Annual Business Trade Show & Conference to Feature Healthcare Pavilion and Expert Panel Discussing Healthcare Economics and Politics
Post Your Comments:
(Date:6/24/2016)... (PRWEB) , ... June 24, 2016 , ... June 19, ... the dangers associated with chronic pain and the benefits of holistic treatments, Serenity ... who are suffering with Sickle Cell Disease. , Sickle Cell Disease (SCD) is a ...
(Date:6/24/2016)... ... June 24, 2016 , ... The Pulmonary Hypertension ... that it will receive two significant new grants to support its work to ... its 25th anniversary by recognizing patients, medical professionals and scientists for their work ...
(Date:6/24/2016)... ... June 24, 2016 , ... Dr. ... accelerated orthodontic treatment. Dr. Cheng has extensive experience with all areas of orthodontics, ... and accelerated osteogenic orthodontics. , Micro-osteoperforation is a revolutionary adjunct to orthodontic ...
(Date:6/24/2016)... ... , ... Topical BioMedics, Inc, makers of Topricin and MyPainAway Pain Relief Products, join The ‘Business ... to $12 an hour by 2020 and then adjusting it yearly to increase at the ... minimum wage, assure the wage floor does not erode again, and make future increases more ...
(Date:6/24/2016)... Norcross, Georgia (PRWEB) , ... June 24, 2016 ... ... Year” awards today at the Clinical Decision Making in Emergency Medicine conference in ... who have authored journal articles published in Emergency Medicine Practice and ...
Breaking Medicine News(10 mins):
(Date:6/24/2016)... 2016   Pulmatrix, Inc ., (NASDAQ: ... drugs, announced today that it was added to the ... its comprehensive set of U.S. and global equity indexes ... important milestone for Pulmatrix," said Chief Executive Officer ... our progress in developing drugs for crucial unmet medical ...
(Date:6/23/2016)... 23, 2016 Any dentist who has made an ... current process. Many of them do not even offer this ... and high laboratory costs involved. And those who ARE able ... such a high cost that the majority of today,s patients ... Parsa Zadeh , founder of Dental Evolutions Inc. and ...
(Date:6/23/2016)... , June 23, 2016 ... CAPR ), a biotechnology company focused on ... today announced that patient enrollment in its ongoing ... Duchenne) has exceeded 50% of its 24-patient target. ... in the third quarter of 2016, and to ...
Breaking Medicine Technology: