Gene editing strategies, from epigenetic engineering to cell reprogramming and genetic vaccines, are accelerating the development of new therapies that awaken the immune system to treat cancer, as presented last month in Rome at the 31st Annual Congress of the European Society of Gene and Cell Therapy (ESGCT). Some of these advances are taking advantage of the conditions of the tumor microenvironment, where cancer cells coexist with immune cells, microorganisms and blood vessels.