Cancer Cytogenetics - GO THROUGH END AGAIN Flashcards
which techniques are used for both constitutional and cancer cytogenetics?
- karyotype
- FISH
- chromosome microarray analysis (CMA)
CMA compared to karyotyping and fish
- used less frequently to analyze cancer specimens
numerical abnormalities
- chromosomal abnormalities that change the number of chromosomes
structural abnormalities
- chromosomal abnormalities that change the structure of the chromosome
chromosome abnormalities cause disease by
- altering concentration of particular gene products
- altering gene product
ways to alter concentration of particular gene products
- duplication or amplification
- deletion or gene interruption
what kind of genes are typically duplicated or amplified in cancer
- oncogenes
what kind of genes are typically deleted or disrupted in cancer?
- tumor suppressor genes
how does cancer alter the gene product?
- produces a few fusion gene with altered expression
- new fusion protein with altered function
CML accounts for what percent of leukemia
15-20%
CML occurs most frequently in what age group
40-50
importance of CML
- first cancer to be associated with a specific recurrent chromosome abnormality
chromosome problems in CML
- Ph chromosome secondary to a (9;22) translocation
the Philadelphia chromosome contains a
- fusion gene composed of BCR serine/threonine on 22 and ABL1 tyrosine kinase on 9
the new fusion BCR/ABL1 tyrosine kinase produced by the fusion gene
- permanently turned-on
- activates a number of signaling pathways
permanent activation of BCR/ABL1 fusion kinase leads to
- malignant transformation
- by interfering with basic cellular processes
what process is used to identify that BCR/ABL1 fusion gene
- FISH
what do you see on FISH in BCR/ABL1 fusion
- yellow fusion signal on part of 9 and part of 22