Preclinical data with antigen-drug conjugate, anti-PTK7 (PF-06647020), in breast, ovarian, and non-small cell lung cancer, shows that PTK7 targeting of CSCs and the tumor microenvironment induces direct and indirect anti-tumor effects, by reducing tumor initiating cells and inducing sustained tumor regression (106). Here, PTK7 is linked to non-small cell lung carcinoma.