Recent studies have documented a frequent association between the emergence and aggressiveness of hormone-sensitive tumors, such as breast and thyroid cancer, and environmental pollutants. This represents the starting point for Asteroid, a new project funded by the Ministry of University and Research (Mur) under the Prin 2020 call and rated as the best project (ranked for the first time in the ERC LS3 sector). The study was conducted by a team of researchers from different universities with complementary and interdisciplinary skills. The coordinator is Michele Melilla, Head of Clinical Oncology at the University of Verona’s Department of Medicine who will provide his skills in clinical and translational studies of breast cancer, in collaboration with the Gemelli Polyclinic Foundation. The University of Siena will contribute with Maria Grazia Castagna from the Department of Medical, Surgical and Neurosciences to the clinical study of thyroid cancer. The University of Rome Tor Vergata will work with Roberto Pai of the Department of Clinical Sciences and Translational Medicine to develop and characterize preclinical models of the two tumors to analyze the effects of environmental pollutants and their molecular targets to identify new therapeutic strategies. Silvia Megliacchio of the Department of Human Kinetics and Health at the University of Rome Foro Italico will deal with the impact of the environment and lifestyles, paying particular attention to nutritional aspects and physical activity. Sapienza University of Rome with Elisabetta Ferretti of the Department of Experimental Medicine – the department that has received 6 other grants under the same call – will coordinate the analysis of new circulating biomarkers and molecular and cellular characterization by means of “omics” techniques, both preclinical models and clinical samples. The study, “Genetic/Environmental Interactions in Breast and Thyroid Cancers: Defining the Biological Role, Action of Endocrine Factors and Lifestyle for the Development of Rational Therapeutic/Preventive Interventions (Asteroid)” will investigate the complex interaction between genes and environment in these two tumors. The research will begin with a retrospective and proactive analysis of patients with these tumors in which the associations between the genetic aspects of each tumor and the patients’ lifestyle will be highlighted. Moreover, the molecular environmental problems of the action of pollutants in preclinical models of different tumor types will be identified. On the basis of the results obtained, the results from a structured lifestyle intervention focused on appropriate nutritional and exercise advice for patients with these tumors will be tested.