THE 02 RECEPTOR IS AN IMPORTANT TARGET FOR THE DEVELOPMENT OF MOLECULES IN ONCOLOGY BECAUSE OF ITS DENSITY (DENSITY) IS TEN-SOLD IN PROLIFERATING TUMOR CELLS COMPARED WITH TUMOR CELLS SILENCE/BENIGN (QUIESCENT TUMOR CELLS) AND ALSO BECAUSE OF THE OBSERVATION THAT THE O2 RECEPTOR AGONISTS ARE ABLE TO KILL TUMOR CELLS THROUGH THE MECHANISM OF APOPTOSIS AND NON APOPTOTIC