TWIST1 and neoplasm: The lack of T cell infiltration in the cold tumor lesions may be due to one or more factors such as dearth of tumor antigens, defect in antigen processing and presentation, lack of T cell activation, and inability of T cells to home in on the tumor.41 The data presented indicate that single modality treatments of Ad-Twist+N-803, OX40+4-1BB, and docetaxel have no effect on 4T1 primary and metastatic growth (figure 4B–D).