a 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.Sep 4, 2009
What is clonal selection in cancer formation?
Table 1
| Burnet's Clonal Selection Theory | Tumor Evolution Theory |
|---|---|
| Focuses on the functions of lymphocytes, specifically their response to antigens that attack the body | Focuses on the significance of natural selection in the development of cancers |
What is clonal evolution in CLL?
CLL treatment has consistently been shown to fuel clonal evolution, resulting in fitter subclones with higher growth rates at the time of relapse. The resultant evolutionary pattern can be seen as a function of the pre-existing subclonal landscape at the time of treatment, and the nature of that CLL treatment.
What does clonal mean?
Clonality implies the state of a cell or a substance being derived from one source or the other. Thus there are terms like polyclonal—derived from many clones; oligoclonal—derived from a few clones; and monoclonal—derived from one clone. These terms are most commonly used in context of antibodies or immunocytes.
What is clonal expansion?
Definition. The proliferation of B-lymphocytes and T-lymphocytes activated by clonal selection in order to produce a clone of identical cells. This enables the body to have sufficient numbers of antigen-specific lymphocytes to mount an effective immune response.
Why are cancer cells clonal?
In most cases, transformation and metastases are probably clonal2 because they are derived from single cells; therefore, the identification of the mutations present in all of the cells of a tumour can help to reconstruct the genotype of the founder cell.
Is CLL clonal?
We found that clonal evolution occurs in all CLL patients, irrespective of the clinical outcome, but is faster during disease progression. In particular, changes in the frequency of nucleotide variants (NVs) in specific CLL-related genes may represent an indicator of poor clinical outcome.
How does leukemia evolve?
Childhood leukemia is a developmental disease thought to evolve in two distinct developmental stages (Hong et al., 2008). An initiating somatic genetic event occurs in fetal hematopoietic progenitors in utero, causing an expansion of a pre-leukemic clone.
What is meant by clonal expansion?
Definition. The proliferation of B-lymphocytes and T-lymphocytes activated by clonal selection in order to produce a clone of identical cells. This enables the body to have sufficient numbers of antigen-specific lymphocytes to mount an effective immune response.
What is clonal expansion so important?
Clonal expansion not only serves to amplify the number of specific lymphocytes to mount a robust protective response to the pathogen at hand but also results in selection and differentiation of the responding lymphocytes to generate a multitude of cell fates.