‘Almost every cancer is unique,’ genes show

The study, published recently in the journal Nature, is part of an international initiative to sequence the genomes of a variety of cancers. Breast cancer researchers examined all the genes in the genomes of 100 cases of breast cancer. Mutated cancer-causing genes (called driver genes) were different in different cancer samples, indicating that breast cancer is genetically very diverse, says Sunil Lakhani, professor from the Centre for Clinical Research at the University of Queensland. “Understanding the consequences of this diversity will be important in progressing towards more rational treatment,” he says. “The idea behind the work was to establish ‘the landscape’ of genetic changes in breast cancer with a view to understanding which genes drive a breast cell to become cancerous. “Recently, we have begun to appreciate that breast cancer is not one disease but has several different subtypes. However, what the study shows is that the diversity and differences between patients is much greater than appreciated. “Although 28 of the 100 cancers had a single driver mutation, some had as many as six. There were 40 different cancer genes implicated in the development of the cancer and in 73 different combinations—almost every cancer is therefore unique. “It is showing us that we will have to use broad information about cancer subtypes (as we do at present in the clinic) and combine it with the unique genomic features of each patients cancer in order to provide individualized treatment plans—which will be a challenge, but hopefully will also improve outcomes by providing new opportunities to target the mutations with specific drugs.” (futurity)