Researchers at the Hospital de Mar Research Institute have discovered that the protein LOXL2 has a function within the cell nucleus. A newly-discovered chemical reaction of this protein on histone H3 is involved in gene silencing, which contributes to the progression of breast, larynx, lung and skin tumors. LOXL2’s action at the intra-cellular level and its interaction with histone H3 stimulates tumor growth. In tumor cells, LOXL2 acts upon H3 and modifies it, eliminating the lysine 4 amino group. Because of this reaction, the genes modulated by H3 and modified by LOXL2 stop expression, preventing cells from behaving normally and favoring tumor development.