How melanoma and other tumors succeed in hiding and resisting immunotherapy
Source: Medical Xpress, March 2025
Cutaneous melanoma, the most aggressive form of skin cancer, is characterized by its accumulation of a large number of mutations. Although some of these alterations should be recognized as a threat by our defenses, melanomas often escape immune system surveillance. As a result, more than half of patients do not generally respond to current immunotherapies. Understanding and avoiding this phenomenon is one of the greatest challenges in oncology today.
Now, a study by the Melanoma Group at the National Cancer Research Center (CNIO), led by Marisol Soengas, has discovered a mechanism by which melanomas and other aggressive tumors prevent the immune system from recognizing and attacking them, as one might expect. The study also helps to understand why when melanoma spreads to other organs, leading to metastases, it often develops resistance to conventional immunotherapy.
The research paper is published in Nature Cancer, with Xavier Catena, currently at the University of Lund (Sweden), as the first author. After conducting studies on cells, mice and more than 150 patient databases, the team found that melanoma cells secrete a protein, called Midkine, which reduces the number of a type of cell specialized in tumor recognition: dendritic cells.