Cancer Stem Cells: Foe or Reprogrammable Cells for Efficient Cancer Therapy?

Abstract

Embryonic development and carcinogenesis share many molecular pathways and regulatory molecules. While the induction of a pluripotent state involves a significant oncogenic risk, as in induced pluripotent stem cells (iPSCs), the embryonic environment in vivo has been shown to suppress tumor development. In this review, we discuss the subtle equilibrium between the nanotopography (niche) of the hosting tissue resident stem cells and their biological dynamics, including the transformation in cancer stem cells. We review consistent findings indicating the potential for modulating the biology of human cancer stem cells by the aid of naturally occurring or synthetic molecules, including developmental stage zebrafish embryo extracts, hyaluronan, butyric acid (BA) and retinoic acid (RA), hyaluronan mixed esters of BA and RA, melatonin, vitamin D3, and endorphin peptides. Within this context, we dissect the multifaceted mechanisms orchestrated by endorphinergic systems, including paracrine cellto-cell communication, as well as the establishment of autocrine and intracrine (intracellular) peptide actions driving transcriptional responses and self-sustaining loops that behave as long-lived signals imparting features characteristic of differentiation, growth regulation and cell memory.Based upon the remarkable action of electromagnetic fields and mechanical vibration on (stem) cell signaling, differentiation, and senescence, we also consider the potential for using these physical energies as a tool to afford a fine tuning of cancer stem cell fate.On the whole, we forecast future deployment of the physical and/or chemical approaches described herein aiming at reprogramming, rather than destroying cancer stem cells, eventually placing cancer therapy within the context of Regenerative Medicine.