In mouse PC models, lineage tracing with PTEN knockout as the oncogenic signal indicated PCSC as an origin of PC (Section 3), and suggested partial EMT as a factor inducing metastasis (Section 4); the inactivation of PTEN with the concurrent inactivation of TP53 and RB1 contributed to lineage plasticity leading to PCSCs (Section 5.3). This evidence concerns the gene RB1 and pachyonychia congenita.