What is the cancer stem cell model?
The cancer stem cell model, also known as the Hierarchical Model proposes that tumors are hierarchically organized (CSCs lying at the apex (Fig. 3).)
What is the clonal evolution model of cancer?
The clonal evolution model holds that genetic and epigenetic changes occur over time in individual cancer cells, and that if such changes confer a selective advantage they will allow individual clones of cancer cells to out-compete other clones.
How do stem cells relate to evolution?
All organisms depend on stem cells for their survival. As a result, stem cells may be a prerequisite for the evolution of specific characteristics in organisms that include regeneration, multicellularity and coloniality. Stem cells have attracted the attention of biologists and medical scientists for a long time.
How do cancer cells undergo evolution?
Cancer development within an individual is also an evolutionary process, which in many respects mirrors species evolution. Species evolve by mutation and selection acting on individuals in a population; tumors evolve by mutation and selection acting on cells in a tissue.
What is the origin of cancer stem cells?
Cancer stem cells might be derived from tissue-specific stem cells and bone marrow stem cells. They might also be derived from somatic cells that undergo transdifferentiation processes. Furthermore, cancer stem cells might be initiated as a result of cell fusion or horizontal gene-transfer processes.
What is are the characteristics of cancer stem cells?
Cancer stem cells (CSCs) have the ability to self-renew and differentiate to give rise to heterogeneous phenotype of the tumor cells. It is believed that these cells are involved in metastasis, recurrence and therapy resistance in various cancers.
Which of the following statements best describes the clonal evolution of tumors?
Which statement best describes the clonal evolution of tumors? Tumor cells acquire more somatic mutations that allow them to become increasingly more aggressive in their proliferative properties.
What is the role of treatment in cancer clonal evolution?
In this context, clonal evolution plays an important role determining tumor responses to treatment. Recent treatment approaches involve the specific targeting of molecular defects in cells that are responsible for driving uncontrolled cell growth.
How is stem cell differentiation?
Stem cell differentiation involves the changing of a cell to a more specialized cell type, involving a switch from proliferation to specialization. This involves a succession of alterations in cell morphology, membrane potential, metabolic activity and responsiveness to certain signals.
Why stem cells are important in the development of multicellular organisms?
Stem cells function as a source of new cells to grow or replace specialised tissues. To perform this function, these cells must divide to renew themselves, while some of their descendants eventually differentiate to build up new tissues.
How has cancer treatment evolved as scientists have learned more about cancer?
As scientists have learned more about the basic mechanics of cancer cells – particularly the molecular changes that allow normal cells to become cancerous and to grow and spread in the body – they’ve found new ways of intervening in the cancer process.
What do cancer cells have to learn how do you grow without?
Professor Robert Weinberg explains that cancer cells have to learn how to grow in the absence of growth stimulatory signals that normal cells require from their environment.
What is the history of stem cell research?
The modern era of stem cell research began in 1961 with the pioneering studies of Till and McCulloch who developed a clonal in vivo repopulation assay and used it to show that a single hematopoietic cell had multilineage differentiation potential while still retaining the property of self-renewal.
Is the cancer stem cell model mutually exclusive?
Although often considered as mutually exclusive models to describe tum … Evolution of the cancer stem cell model Cell Stem Cell. 2014 Mar 6;14(3):275-91.doi: 10.1016/j.stem.2014.02.006.
Do cancer stem cells drive tumor growth?
However, it is becoming increasingly clear that cancer cells display features of normal tissue organization, where cancer stem cells (CSCs) can drive tumor growth. Although often considered as mutually exclusive models to describe tum … Genetic analyses have shaped much of our understanding of cancer.
Is there a dynamic model of tumor development?
Thus, a dynamic model emerges where early in tumor progression the tumor is a close caricature of the developmental hierarchy of the tissue from which it arose, with a minority T-IC and a high proportion of more differentiated non-T-IC ( Figure 2 ).