Figure 1.
Generation of iPSC, induced epithelial stem cell (iESC), and induced cancer stem-like cell (iCSC) lines.
(A) Generation of iPSCs and iESCs through direct reprogramming of primary fetal fibroblasts (TIG1). (B) Generation of the first (1st) iCSCs by picking a cell clump (yellow circle) through iESCs-derived embryoid bodies (iESC EB) formation. (C) Generation of the second (2nd) iCSCs by picking a cell clump (yellow circle) through serial transplantation of the 1st iCSCs.
Figure 2.
Pluripotent tumorigenicity of iESCs and iCSCs.
(A) Expression of exogenous, pluripotent marker, and lineage marker genes in embryoid bodies (EBs) formed with iESCs and iPSCs by RT-PCR analyses. (B) Paraffin sections of teratomas, which were generated by iESCs, 1st iCSCs, and 2nd iCSCs implantation, were stained with hematoxylin and eosin. NE, neuroepithelium (ectoderm); CA, cartilage (ectoderm); MU, muscle (mesoderm); RE, respiratory epithelium (endoderm).
Figure 3.
Global expression analysis of iESCs and iCSCs.
(A) Gene expression microarray analysis among TIG1, iESCs, iCSCs, and iPSCs. Heat map (upper panel) shows differentially expressed genes of somatic and pluripotent genes. Scatter plots (lower panel) show comparison of global gene expression profiles. Yellow; genes in the Core module, Blue; genes in the PRC module, and Red; gene in the Myc module. (B) Expression analysis of pluripotent marker genes, somatic cell marker genes, and exogenous genes in TIG1, iPSCs, iESCs, 1st iCSCs, and 2nd iCSCs by RT-PCR analyses. (C) Expression of pluripotent marker proteins (Green) in iESCs, 1st iCSCs, and 2nd iCSCs by immunocytochemistry. Cell nuclei are counterstained blue with DAPI (Blue). Exo-, exogenous; Endo-, endogenous.
Figure 4.
Activity of CPM modules in human somatic cells and pluripotent stem cells.
Properties of self-renewal and pluripotency are linked with transient or continuous up-regulation of the Core and Myc modules, but not PRC module. C, Core module; P, PRC module; M, Myc module.