Cancer Stem Cells: Formidable Allies of Cancer

Abstract

Cancer stem cells (CSC) represent the subpopulation of cells within a tumour showing two fundamental properties of stem cells -self-renewal (the ability to make more of their own kind) and differentiation (the ability to generate diverse cell types present within a tissue). The CSC hypothesis posits that CSCs play an important role in tumour initiation, maintenance and progression. Furthermore, owing to their intrinsic drug resistance, they remain refractory to currently used therapy, thereby contributing to tumour relapse. Thus, targeting or taming CSCs can lead to more effective cancer treatment in the coming decades. In this review, we will discuss about the origin of CSC hypothesis, evidence showing their existence, clinical relevance and translational significance.

Glioblastoma Microenvironment and Cellular Interactions

“…However, there were distinguished subsets of heterogeneous tumor cells [ 163 , 164 , 165 ], with different cells proportions, histological appearances, procreation rates, expressions of surface markers, metastatic potentials, and responses to chemotherapy. This tumor heterogeneity was also tried to be explained through co-existence of several tumor stem cells that differentiate and create the types of cells that make up the tumor [ 166 , 167 , 168 ].…”

“…According to Feinberg’s theory, the origin of cancer stem cells may be the adult stem cells, with a lifespan that allows them to acquire epigenetic alterations [ 173 ]. The cell division of these tumor-initiating cells is asymmetric: each stem cell forms two daughter cells: one, undifferentiated, maintains the stem cell pool, and the other, a progenitor cell, differentiates and generates a wide range of tumoral cells [ 168 ]. Defects in asymmetric cell division of neuronal stem cells contribute to neoplastic transformation [ 174 ] and GSCs generation.…”

Dichotomy of Notch signalling in regulating tumour immune surveillance

“…Existence of cancer stem cells and their role in tumour initiation and progression is now being supported by various groups . CSCs are a subpopulation of cancer cells, which have the capability to self‐renew as well as to maintain the heterogeneity of tumour mass.…”