The report, published in the April 20 issue of the Journal of Clinical Oncology, describes the case of a 79-year-old woman with melanoma tumors in several parts of her abdomen. When lab tests showed the tumor cells carried an abnormality in a gene called KIT, the patient enrolled in a clinical trial involving Gleevec (R) (Imatinib), a drug known to target that gene.
Four weeks after beginning therapy, imaging exams showed a dramatic reduction in tumor size and metabolism: two of the tumor masses had disappeared and several others had shrunken considerably. Four months later, the tumors were still in check, and today, nine months after the start of therapy, she continues to take the drug and her condition remains stable.
"This is the first proof of principle that we can find an Achilles' heel in melanoma" -- a gene critical to tumor cell growth and proliferation -- "and, by targeting that gene with a drug, cause the cell to die," says the study's lead author, Stephen Hodi, MD, of Dana-Farber. "It is especially exciting because there haven't been any effective treatments for melanoma patients with metastatic disease."
Although the report involves just one patient, it should inject new confidence in the fight against melanoma, Hodi says. Because previous research has failed to find any genetic Achilles' heels capable of shutting down melanoma cell growth, some researchers had speculated that none may exist for such cells. The discovery of one suggests there may be others.
KIT mutations are found in only a small percentage of melanomas, so Imatinib does not represent a universal treatment for the disease, Hodi explains. Recent studies have found KIT mutations in 11 percent of acral melanomas (which arise in skin without hair follicles, such as that of the palms, foot soles, and nail beds, and account for 5 percent of all melanomas), 21 percent of mucosal melanomas (which arise in the mucous membranes of some organs), and 17 percent of melanomas arising in chronically sun-damaged skin. For patients with these conditions, particularly those who carry a mutation in a particular section of the gene, Imatinib may well prove beneficial.
Imatinib's effectiveness against tumors with KIT mutations was first demonstrated in gastrointestinal stromal tumors (GISTs), a relatively rare malignancy of the digestive tract. An estimated 75-80 percent of GISTs have KIT mutations, and Imatinib has caused such tumors to stabilize or retreat in 75-90 percent of patients receiving it. In most of these patients, however, tumors eventually begin growing again as they become resistant to the drug.
The KIT mutation in the patient described in the study involved a protein-coding section of the gene where DNA was duplicated. This section, known as the "juxtamembrane domain," is the most frequent site of mutation in GIST, and is associated with a strong tumor response to Imatinib.
"Dramatic remissions in metastatic melanoma are something that, as physicians, we've rarely seen," Hodi remarks. "Confirming these results will require enrolling additional patients in clinical trials -- something we're actively working to accomplish."
Researchers release the brakes on the immune system
18.10.2017 | Rheinische Friedrich-Wilhelms-Universität Bonn
Norovirus evades immune system by hiding out in rare gut cells
12.10.2017 | University of Pennsylvania School of Medicine
University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.
Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...
Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.
It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...
17.10.2017 | Event News
10.10.2017 | Event News
10.10.2017 | Event News
18.10.2017 | Health and Medicine
18.10.2017 | Life Sciences
17.10.2017 | Life Sciences