Stem Cell/Wnt

Stem cells are required for continuous tissue maintenance within diverse organs, stem cell activity is often externally dictated by the microenvironment (the niche) so that stem cell output is precisely shaped to meet homeostatic needs or regenerative demands. Several key signaling pathways have been shown to play essential roles in this regulatory capacity. Specifically, the JAK/STAT, Hedgehog, Wnt, Notch, Smad, PI3K/phosphatase and tensin homolog, and NK-κB signaling pathways have all been shown experimentally to mediate various stem cell properties, such as self-renewal, cell fate decisions, survival, proliferation, and differentiation.

Recent studies mainly focus on cancer stem cell, induced pluripotent stem cell, neural stem cell and maintenance of embryonic stem cell pluripotency. Cancer stem cells (CSCs) have been believed to be responsible for tumor initiation, growth, and recurrence. Numerous agents have been developed to specifically target CSCs by suppressing the expression of pluripotency maintaining factors Nanog, Oct-4, Sox-2, and c-Myc and transcription of GLI. Induced pluripotent stem cells (iPSCs) have the capacity to differentiate into various types of cells, and a self-renewing resource, and scientists can experiment with an unlimited number of pluripotent cells to perfect the process of targeted differentiation, transplantation, and more, for personalized medicine. Novel pathological mechanisms have been elucidated, new drugs originating from iPSC screens are in the pipeline and the first clinical trial using human iPSC-derived products has been initiated.

References:

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[2] Matsui WH. Medicine (Baltimore). 2016 Sep;95(1 Suppl 1):S8-S19.

[3] Koury J, et al. Stem Cells Int. 2017;2017:2925869.

[4] Garg A, et al. Cells. 2017 Feb 2;6(1). doi: 10.3390/cells6010004.