Introduction.- Current Status and Perspectives in Stem Cell Research: the concept of Normal Stem Cell (NSC) and Cancer Stem Cell (CSC).- Essential Characteristics of Stem Cells: Self-Renewal and Plasticity.- Stem Cell Sources and Types of Animal Stem Cells.- Stemness and Stem Cell Markers.- Stem Cell Signaling Molecules and Pathways.- Expansion of Stem Cells: Propagation of Animal Stem Cells Ex Vivo (in Culture).- Stem Cell Pool: What are the Best Patterns for Cellular Therapy?.- Induced Pluripotent Stem Cells (iPSCs) and Nuclear Reprogramming.- Cancer Stem Cell Concept.- Metabolic Reprogramming in Cancer and Metabolic Theory of CSC.- Concept of Targeted Cancer Stem Cell Therapy and New Versions.- HLA Typization Choice of Donors: Match or Match Me Not.- Engraftment: Homing and Use of Genetic Markers and Labels for Tracing.- Nanotechnology in Stem Cell Research.- Stem Cell Therapy: Optimization, Regeneration, Reprogramming, Expansion, Tissue Engineering.- What are Positive Results of Stem Cell Therapies?- Topic Novelties in Animal Stem Cell Research.- Resume.- Stem Cells in Plants: Meristems.- Shoot and Roote Apical Meristems.- Lateral Meristems.- External Control of the Plant Stem Cells.- Signaling and Genetic Regulation of the Plant Stem Cells.- Meristems and Primary and Secondary Growth in a Plant.- Propagation of Plant Stem Cells in Culture.- Cultured Plant Stem Cells as a Source of Plant Natural Products.- Mitochondria, a Vital Organelle in Stem Cell Maintenance.- Molecular Similarities Between Plant and Animal Stem Cells.