New knowledge can develop treatments for lung cancer patients -
The study of the most common form of lung cancer, researchers have found mutations in a cell signaling pathway that plays a role in forming tumors. The new knowledge may develop treatments for patients because drugs targeting some of these genetic changes are already available or are in clinical trials.
Reports July 9 in Nature , investigators from the Cancer Genome Atlas (TCGA), including researchers from the Washington University School of Medicine in St. Louis, and Harvard Medical School other institutions, studied tumors from 230 patients with lung adenocarcinoma.
"This is the first time we had a panoramic look at the genomic landscape of the many lung tumor samples," said oncologist Ramaswamy Govindan, MD, professor of medicine at the University Washington TCGA project lung cancer co-president. "These studies reinforce the view that lung cancer is a very heterogeneous disease."
Combined with a previous study of 178 patients lung squamous cell carcinoma, the TCGA researchers now have published genetic data on 400 patients with lung cancer and are working to analyze 0 more. tumors investigators included scientists from the University of the genomics Institute Washington and other major sequencing centers.
in the new study, among the myriad genetic changes observed in adenocarcinoma, a cell signaling pathway stood out. About 75 percent of the samples had mutations that an overactive pathway called RTK / RAS / RAF, known for her roles in tumor growth.
"It is remarkable that the importance of channel RTK / RAS / RAF seems to be," said Govindan, who treats patients at Siteman Cancer Center at Barnes-Jewish Hospital and University School of Medicine in Washington. "Mutations in this particular way promote cancer cell growth. What is amazing is how many ways this path can be activated.
" We know these tumors are not static, "he added. " They evolve. We should be looking at multiple biopsies over time to see how tumor cells escape by inhibiting a pathway and become resistant to treatment. "
The researchers also found other relevant mutations in important genes such as EGFR NF1 NF2 and MET . These results could be useful in a clinical trial known as ALCHEMIST (adjuvant Lung Cancer enrichment marker identification and trial sequencing) that directs Govindan. the trial will involve the screening of tumors thousands of lung cancer patients for gene alterations called EGFR and ALK . After surgery to remove their tumors, these patients will be invited to participate in clinical trials that study drugs targeting these genes dysfunctional.
ALCHEMIST's trial is based on the current study and will also potentially provide additional tumor samples for genomic analysis. A large sample size is important in the accurate identification of mutations that stimulate the growth of the tumor of the lung.
"Lung cancer patients often have substantial exposure to tobacco, which leads to a large number of mutations," said Govindan. "We can not be able to find important mutations unless we examine several samples from thousands of patients."
Despite these advances in lung cancer understanding - the most common cause of cancer death in the world - the researchers point out that the best way to reduce lung cancer deaths is to help people quit smoking and encourage others to never start.
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