KRT19 and neoplasm: The first class contained mainly gene signatures that indicated the progenitor tumor cell origin (CSC_Yamashita (Yamashita et al., 2008), EPCAM_Yamashita (Yamashita et al., 2008), CK19_Andersen (Andersen et al., 2010), S2_Hoshida (Hoshida et al., 2009) and C2_Cario (Cairo et al., 2008)); cellular proliferation (Proli_Chiang (Chiang et al., 2008)); and vascular invasion (VI_Minguez (Minguez et al., 2011)).