Cancer stem cells: Recent advances, signaling and molecular markers

Cancer stem cells (CSCs) are tumor cells with stem-like features that possess the ability to self-renew, but can also give rise to more differentiated progeny. CSC can be identified based on increased in vitro spheroid- or colony formation, enhanced in vivo tumor initiating potential, or expression of cell surface markers. Since CSCs are thought to be required for the maintenance of a tumor cell population, these cells could possibly serve as a therapeutic target. Therapeutics based on CSC markers, epithelial mesenchymal transition, developmental pathways, or tumor micro-environment could potentially be used to target CSC which may lead to a reduction of tumor growth, metastatic events and chemoresistance in various cancers.