Thyroid hormone promotes differentiation of colon cancer stem cells

Colon cancer and colon cancer stem cells. (Left) Representative immunoistochemical image of D3 expression in colon cancer. (Right) Colon cancer stem cells (CSCs) arise from a subpopulation of intestinal stem cells with the ability of self-renewal, but also able to generate a wide variety of more “differentiated” cancer cells, thereby populating the majority of the tumor and providing the basis of tumor heterogeneity. The figure shows different options of anti-cancer treatments. At the top, the conventional therapy kills the bulk of cancer cells, but is not able to eliminate the critical CSCs, which are more resistant to chemotherapy and radiation. Surviving CSCs give rise to new tumors and metastases, causing often relapse after the treatment. At the bottom, a therapy specifically targeting CSCs offers the possibility of eradicating CSCs and impeding regeneration and cancer relapse. Finally, at the middle of the figure, TH treatment differentiates CSCs and makes them more susceptible to conventional therapies, resulting in regression of cancer. By inducing CSCs differentiation, TH may be a powerful druggable agent for cancer treatment.723