Related Experiment Video
Updated: Jun 22, 2026
11:43
Advanced Animal Model of Colorectal Metastasis in Liver: Imaging Techniques and Properties of Metastatic Clones
Published on: November 30, 2016
Many colorectal cancers are "flat" clonal expansions.
Kimberly D Siegmund1, Paul Marjoram, Simon Tavaré
1Department of Preventive Medicine, University of Southern California Keck School of Medicine, Los Angeles, CA 90033, USA.
Cell Cycle (Georgetown, Tex.)
|June 27, 2009
Summary
Colorectal cancer cell populations grow through clonal expansion, with methylation patterns revealing tumor age and development. Frequent cancer stem cells (CSCs) contribute to tumor diversity and ancestry.
Area of Science:
- Genetics
- Oncology
- Molecular Biology
Background:
- Population genetics uses genetic variation to study population history.
- Human genome variation reflects historical events like the
- out of Africa
- migration.
- Colorectal cancer (CRC) progression involves complex cell population dynamics.
Purpose of the Study:
- To apply population genetic principles to understand colorectal cancer cell population growth.
- To infer tumor development and clonal expansion history using molecular variation.
- To investigate the role of cancer stem cells (CSCs) in CRC.
Main Methods:
- Analysis of polymorphic passenger methylation patterns within individual colorectal tumors.
- Comparison of molecular diversity across different tumor regions (e.g., sides, invasion depth).
- Assessment of epiallele diversity in cancer gland fragments.
Main Results:
- Average molecular diversity varied between cancers, suggesting differences in clonal expansion age.
- Methylation pattern diversity was uniform within individual tumors, supporting a
- flat
- clonal expansion model.
- High epiallele diversity indicated frequent, long-lived cancer stem cell lineages.
Conclusions:
- Many colorectal cancers represent old, uniform clonal expansions.
- Colorectal cancer cell populations harbor frequent, long-lived cancer stem cell lineages.
- Passenger methylation patterns can serve as a record of somatic cell ancestry in cancer.
Related Concept Videos
02:21Cancers Originate from Somatic Mutations in a Single Cell
Cancer arises from mutations in the critical genes that allow healthy cells to escape cell cycle regulation and acquire the ability to proliferate indefinitely. Though originating from a single mutation event in one of the originator cells, cancer progresses when the mutant cell lines continue to gain more and more mutations, and finally, become malignant. For example, chronic myelogenous leukemia (CML) develops initially as a non-lethal increase in white blood cells, which progressively...
02:21Cancers Originate from Somatic Mutations in a Single Cell
Cancer arises from mutations in the critical genes that allow healthy cells to escape cell cycle regulation and acquire the ability to proliferate indefinitely. Though originating from a single mutation event in one of the originator cells, cancer progresses when the mutant cell lines continue to gain more and more mutations, and finally, become malignant. For example, chronic myelogenous leukemia (CML) develops initially as a non-lethal increase in white blood cells, which progressively...
02:30Metastasis
Metastasis is the spread of cancer cells from the original site to distant locations in the body. Cancer cells can spread via blood vessels (hematogenous) as well as lymph vessels in the body.
Epithelial-to-Mesenchymal Transition
The epithelial-to-mesenchymal transition or EMT is a developmental process commonly observed in wound healing, embryogenesis, and cancer metastasis. EMT is induced by transforming growth factor-beta (TGF-β) or receptor tyrosine kinase (RTK) ligands, which further...
Epithelial-to-Mesenchymal Transition
The epithelial-to-mesenchymal transition or EMT is a developmental process commonly observed in wound healing, embryogenesis, and cancer metastasis. EMT is induced by transforming growth factor-beta (TGF-β) or receptor tyrosine kinase (RTK) ligands, which further...
02:07Tumor Progression
Tumor progression is a phenomenon where the pre-formed tumor acquires successive mutations to become clinically more aggressive and malignant. In the 1950s, Foulds first described the stepwise progression of cancer cells through successive stages.
Colon cancer is one of the best-documented examples of tumor progression. Early mutation in the APC gene in colon cells causes a small growth on the colon wall called a polyp. With time, this polyp grows into a benign, pre-cancerous tumor. Further...
Colon cancer is one of the best-documented examples of tumor progression. Early mutation in the APC gene in colon cells causes a small growth on the colon wall called a polyp. With time, this polyp grows into a benign, pre-cancerous tumor. Further...
02:40Cancer Stem Cells and Tumor Maintenance
Early diagnosis and treatment can often cure cancer. However, even with treatment, residual cells called cancer stem cells (CSC) might remain, often causing tumor recurrence. These cancer stem cells possess the potential for self-renewal and multi-lineage differentiation and are often responsible for the therapeutic resistance displayed in most cancers.
Cancer stem cells are thought to originate from tissue-specific normal stem cells or progenitor cells. The normal stem cells usually reside in...
Cancer stem cells are thought to originate from tissue-specific normal stem cells or progenitor cells. The normal stem cells usually reside in...