Doxycycline-treated ESΔN-iNanog and ESΔN-iEsrrb cells could be passaged in the presence of LIF antagonist for more than 1 month (Figure S4B) and retained the ability to form teratocarcinomas composed of representative tissues of all three primary germ layers as well as undifferentiated embryonal carcinoma (EC) upon transplantation to mice (Figure S4C; Table S2). This evidence concerns the gene LIF and embryonal carcinoma.