摘要
The origins of the complex process of intratumoral heterogeneity have been highly debated and different cellular mechanisms have been hypothesized to account for the diversity within a tumor. The clonal evolution and cancer stem cell(CSC) models have been proposed as drivers of this heterogeneity. However, the concept of cancer stem cell plasticity and bidirectional conversion between stem and non-stem cells has added additional complexity to these highly studied paradigms and may help explain the tumor heterogeneity observed in solid tumors. The process of cancer stem cell plasticity in which cancer cel s harbor the dynamic ability of shifting from a non-CSC state to a CSC state and vice versa may be modulated by specific microenvironmental signals and cellular interactions arising in the tumor niche. In addition to promoting CSC plasticity, these interactions may contribute to the cellular transformation of tumor cells and affect response to chemotherapeutic and radiation treatments by providing CSCs protection from these agents. Herein, we review the literature in support of this dynamic CSC state, discuss the effectors of plasticity, and examine their role in the development and treatment of cancer.
The origins of the complex process of intratumoralheterogeneity have been highly debated and differentcellular mechanisms have been hypothesized to accountfor the diversity within a tumor. The clonal evolution andcancer stem cell (CSC) models have been proposed asdrivers of this heterogeneity. However, the concept ofcancer stem cell plasticity and bidirectional conversionbetween stem and non-stem cells has added additionalcomplexity to these highly studied paradigms and may helpexplain the tumor heterogeneity observed in solid tumors.The process of cancer stem cell plasticity in which cancercells harbor the dynamic ability of shifting from a non-CSCstate to a CSC state and vice versa may be modulated byspecific microenvironmental signals and cellular interactionsarising in the tumor niche. In addition to promoting CSCplasticity, these interactions may contribute to the cellulartransformation of tumor cells and affect response tochemotherapeutic and radiation treatments by providingCSCs protection from these agents. Herein, we review theliterature in support of this dynamic CSC state, discussthe effectors of plasticity, and examine their role in thedevelopment and treatment of cancer.