• An international research describes the processes that harm the DNA and lead to cancer

    August 14, 2013

    Teams from 14 countries have studied more than 7,000 tumoral genomes and have discovered more than 20 different processes that cause the mutations of the 30 most common types of cancer. The research is published today in Nature.

    A research by the International Consortium for the Cancer Genome, published in the journal Nature, offers the firs exhaustive compilation of the process that generate the development of tumors. These processes explain the majority of the mutations found in the 30 most common types of cancer. This new information may help prevent a wide range of cancers. This important discovery is the result of the international collaboration of teams of researchers from 14 countries, with Spain among them, and which has been coordinated by Dr. Michael Stratton of the Sanger Institute (Cambridge, United Kingdom). The Tenured Professor of Biochemistry and Molecular Biology of the University of Oviedo Carlos López-Otín and two members of his team (Xose S. Puente and Rafael Valdés), have participated in this study, alongside Doctor Elías Campo (Clinic Hospital), in this study with the identification of the essential mechanisms that cause mutations in Chronic Lymphatic Leukemia.

    All the cancers are originated by a mutation in the DNA of the cells of the organism throughout the life of a person, so that, depending on the causes, each mutational process leaves a particular pattern, a distinctive signature of mutations, in the genome of each tumor. Until now, scientists knew of the mutational signatures left by agents such as tobacco or ultraviolet light, responsible for the development of certain cancers, but the mechanisms involved in the generation of the majority of tumors were unknown. In this research, 7,042 genomes from patients of the most common types of cancer have been studied, and more than 20 molecular signatures have been discovered among the mutations of genetic material. Furthermore, the underlaying biological processes of the majority of these mutational processes have been discovered. Some of these mutational signatures are present in different types of tumors, and some other are specific to a certain type of tumor. Curiously, some tumors only present to mutational signatures, which suggests that they are causes by a limited number of mechanisms. Nevertheless, other types of cancer have up to six different mutational signatures, which indicates that the mechanisms that generate them are more complex.

    The researchers from the University of Oviedo Carlos López-Otín, Xose S. Puente and Rafael Valdés, alongside Doctor Elías Campo, from the Clinic Hospital, have identified the basic mechanisms that cause mutations in Chronic Lymphatic Leukemia

    The team that has been working on the project in Spain is led by Dr. Carlos López-Otrín, from teh University Institute of Oncology of the University of Oviedo, and Dr. Elías Campo, from the Clinic Hospital-IDIBAPS and the University of Barcelona. The Spanish team contributed to the project with the identification of two basic mechanisms that cause mutations in Chronic Lymphatic Leukemia: one of them related to aging and the other one related to the regeneration of damaged DNA. In total, the Spanish scientific team has studied in detail the mutational signatures of more than 100 genomes of patients of this type of leukemia, an analysis to which Dr. Xose S. Puente and Rafael Valdés, from the University of Oviedo, have also contributed.

    Dr. Carlos López-Otín has remarked that "without the strong international collaboration between all the work groups involved in this project, it would have been impossible to obtain these important results. The detailed analysis of the information now generated will allow us to develop new approximations to the study of the molecular mechanisms that generate the different types of tumors".

    In turn, Dr. Elías Campos indicates that "the majority of the mutational signatures that causes the genetic development and history of the cancers we studided have been identified. We are facing one of the first examples of the new vision offered by the massive and coordinated sequencing of genomes of different types of cancer through the International Consortium for the Cancer Genome.

    "The definition of this map of mutational processes", explain those in charge of the project in Spain, "implies an important step forward to discover how and why these cancers are formed. This compendium of mutational signatures and the subsequent perspectives on the underlaying mutational processes have deep implications for the understanding of the development of cancer, with potential applications in the prevention and treatment of the disease".

    The Spanish Consortium for the Study of the Genome of Chronic Lymphatic Leukemia ( is funded by the Ministry of Economics and Competitiveness through the Carlos III Health Institute, and is framed within the International Consortium for the Cancer Genome (ICGC) ( From the start of this project in 2009, the Spanish consortium has published the advances of the Spanish participants in the ICGC, based on the decyphering of the genomic and epigenomic alterations of more than 100 patients of Chronic Lymphatic Leukemia. This new joint research of several groups of the consortium is an example of the qualitative jump that is being made in the research of cancer.