Concise Review: Recent Advances on the Significance of Stem Cells in Tissue Regeneration and Cancer Therapies

Abstract

In this study, we report on recent advances on the functions of embryonic, fetal, and adult stem cell progenitors for tissue regeneration and cancer therapies. We describe new procedures for derivation and maturation of these stem cells into the tissue-specific cell progenitors. The localization of the adult stem cells and their niches, as well as their implication in the tissue repair after injuries and during cancer progression, are also described. The emphasis is on the interactions among certain developmental signaling factors, such as hormones, epidermal growth factor, hedgehog, Wnt/␤-catenin, and Notch. These factors and their pathways are involved in the stringent regulation of the self-renewal and/or differentiation of adult stem cells. Novel strategies for the treatment of both diverse degenerating disorders, by cell replacement, and some metastatic cancer types, by molecular targeting multiple tumorigenic signaling elements in cancer progenitor cells, are also illustrated. STEM CELLS 2006;24:2319 -2345

Accumulation of Hedgehog-Responsive Progenitors Parallels Alcoholic Liver Disease Severity in Mice and Humans

“…14 -16 This insight has potential relevance for liver repair because Hh signaling orchestrates embryogenesis, as well as the remodeling of many adult tissues after injury. [17][18][19][20][21][22][23][24] We reported that bile duct injury is accompanied by strong induction of Hh signaling in portal tract stromal cells and bile ductular cells in both rodents and humans. 16,25 However, it is not clear whether parenchymal liver damage, such as that induced by chronic alcohol consumption, leads to similar activation of Hh signaling.…”

Pluripotent plasticity of stem cells and liver repopulation

“…They are involved in the stringent regulation of the self-renewal and/or differentiation of adult stem cells. 89,91 Of particular importance is the Wnt/b-catenin pathway because of its involvement in liver growth, regeneration, and cancer as well as its role in epithelial-mesenchymal transitions. [92][93][94][95] High levels of bcatenin protein expression is present in liver at embryonic day 10 (E10) through E14 of liver development.…”

Stem cells: The therapeutic role in the treatment of diabetes mellitus

“…Although the modification of differentiation protocol allowed the generation of insulin-producing cells from mouse and human Es cells, further improvements are necessary to generate functional pancreatic islet like clusters. Although Es cells could be used as an available source to obtain large amounts of transplantable cells as regenerative medicine as in the case of T1dms, the major obstacle to the successful and safe clinical use of differentiated cells is the possibility of immune rejection and teratomas or teratocarcinoma formation in the recipients (mimeault and Batra 2006;. more recently, kroon et al showed that pancreatic endoderm derived from human embryonic stem (doss mX) cells efficiently generates glucose-responsive endocrine cells after implantation into mice.…”

“…Although ES cells could be used as an available source to obtain large amounts of transplantable cells as regenerative medicine as in the case of T1DMs, the major obstacle to the successful and safe clinical use of differentiated cells is the possibility of immune rejection and teratomas or teratocarcinoma formation in the recipients (Mimeault and Batra 2006;.…”