An international team of scientists report finding 57 genomic regions that are frequently gained or lost in human lung tumors. Among these results from their effort to map genetic changes underlying the disease are 40 regions previously unassociated with lung cancer, they add.
The effort, known as the Tumor Sequencing Project (TSP), studied more than 500 tumor specimens from lung cancer patients. The regions of genomic aberration were reportedly identified with tools including a computational method called GISTIC and techniques for visualizing SNP data developed by some of the collaborators.
The researchers say that they uncovered 57 genomic changes that occur frequently in lung cancer patients. Of these, only about 15 are linked to genes previously known to be involved in lung cancer.
The most common abnormality involves a region on chromosome 14 that encompasses two genes, neither of which had been previously associated with cancer, report the researchers. Through additional studies in cancer cells, the team found that one of the genes, NKX2.1, influences cancer cell growth. The NKX2.1 gene normally acts as a master regulator in a group of cells lining alveoli. They also report finding that NKX2.1 is essential for the survival of lung cancer cell lines that express the gene.
The second phase of the TSP, now underway, will examine the same lung tumor samples analyzed in the first phase, but at an even greater level of genetic detail, the research team notes. They will characterize small changes in the genetic code of several hundred human genes that are already implicated in other cancers, or more generally, in cell growth.
TSP involves three genome centers and five cancer centers: Baylor College of Medicine Human Genome Sequencing Center, The Broad Institute, and Washington University in St. Louis, Dana-Farber Cancer Institute, The University of Texas M. D. Anderson Cancer Center, Memorial Sloan-Kettering Cancer Center, University of Michigan, and Washington University.
The study appeared in the November 4 advance online issue of Nature.