Intriguingly, expression of PCDH7 and PCDH10, which are generally considered to be tumor suppressor genes, has been proven necessary for the tumorigenicity of non-small cell lung cancer and glioblastoma, respectively (Echizen et al., 2014; Zhou X. et al., 2017). The gene discussed is PCDH7; the disease is non-small cell lung carcinoma.