Chapter 13: Cancer stem cells

Question 1

Name at least 4 pathways that have been documented shared between stem cells, cancer and cancer stem cells

Answer 1

Hedgehog
WNT
NOTCH
HOX
SOX
MAMOG
TGF-beta
BM1

Question 2

Does the expression and activation of the embryonic stem cells pathways imply a hierarchical organisation of cancer?

Answer 2

No- it most likely reflects the parsimonious use of molecular programs useful for cell renewal, dormancy, migration and metastasis.

Question 3

How do we define cancer stem cells?

Answer 3

1. By their ability to generate tumours on serial transplantation
2. By their ability to recapitulate the genetic and phenotypic heterogeneity of the original tumour
3. Have a potent tumour initiation ability

Question 4

Name some different stem cell markers?

Answer 4

CD133
CD 24
CD 44

Question 5

Which tumours have SCS been confirmed?

Answer 5

AML- human
SCC - human
Canine BCL and TCL

Question 6

Stem cell lineage markers:

Answer 6

Epithelial CD44+/CD24- and lineage negative
Neuronal CD133+/
Melanoma - no specific marker identified, almost all seem to be CSCs in a melanoma

Question 7

What is the main difference between the SCS and EMT model?

Answer 7

SCS defined as a irreversible hierarchial hypothesis, where stem-like cells proliferate to terminally differentiated post-mitotic progeny. In the EMT theory there is reversibility, cells with one phenotype may take on another under the appropriate microenvironmental stimulis

Question 8

Define EMT?

Answer 8

Transdifferentiation from one morphology and function to another