The research group on CIBBIM-Nanomedicine, Drug Delivery and Targeting of the Vall d'Hebron Research Institute (VHIR) has recently participated in a study with the aim of finding a useful treatment to combat colorectal cancer, but also to eradicate cancer stem cells. The study notes that nanotechnology-based therapies emerge as promising therapeutic strategies for a wide spectrum of clinical indications in this area. This work, in which the CIBER-BBN Translational Research Centre has also participated, has been published in the Journal of Controlled Release under the title "https://www.sciencedirect.com/science/article/pii/S0168365921000316?dgcid=author Polymeric micelles targeted against CD44v6 receptor increase niclosamide efficacy against colorectal cancer stem cells and reduce circulating tumor cells in vivo".Colorectal cancer is the second leading cause of death and the third most common type of cancer worldwide. Thus, the treatment of advanced colorectal cancer is still considered an unmet clinical need. Targeted therapies based on nanotechnology have emerged as promising therapeutic strategies in recent years. However, it is true that despite great research efforts in this field, the development of advanced forms of the disease and cancer relapse remain a major challenge.The formation of metastases and the recurrence of this type of cancer are due to the presence of cancer stem cells within the tumor, which resist treatment, causing highly aggressive forms of the disease. Therefore, the treatment of cancer stem cells, as well as differentiated tumor cells, is of utmost importance.The research group on CIBBIM-Nanomedicine, Drug Delivery and Targeting of the VHIR and the CIBER-BBN, in collaboration with Bruno Sarmento (University of Porto, Portugal) and Marika Nestor (University of Uppsala, Sweden), have led the research.The study has demonstrated the effectiveness of a type of targeted nanoparticles (magic bullets) that carry a drug in their nucleus, which are capable of reaching tumor tissue due to their small dimensions. In this way, the drug reaches cancer stem cells, specifically recognizing the CD44v6 receptor, which is present in greater quantity in these cells, being associated with the development of metastasis and poor prognosis in patients.This system has managed to significantly decrease the circulating tumor cells, precursors of metastasis, thus reducing the malignancy of the disease. This new strategy has the potential to create a new therapeutic approach that could improve colorectal cancer treatment and prevention of disease relapse.The work brings together several scientific areas, such as nanotechnology, nanomedicine, pharmacy, chemistry, molecular biology and medicine. For this reason, Dr. Fernanda Andrade and Dr. Diana Rafael, first authors of the study, consider that "the results will be of great interest for the development of targeted and specific therapies with which to combat advanced colorectal cancer or other types of cancer, where CD44v6 is over-expressed".