Fluorescent In Situ Hybridization (FISH) to Identify Genetic Changes in Fine Needle Biopsy of Lung...
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Transcript of Fluorescent In Situ Hybridization (FISH) to Identify Genetic Changes in Fine Needle Biopsy of Lung...
Fluorescent In Situ Hybridization (FISH) to Identify Genetic Changes in Fine
Needle Biopsy of Lung Lesions
Prepared by Jin JenNCI
Why the Need?
• Spiral CT screening is highly sensitive for detecting lung cancers in patients at high risk.
• Spiral CT plus fine needle biopsy increases the diagnostic rate of accurate diagnoses but a portion of the cases are undetermined.
• Molecular markers might be used to assist clinical diagnosis by detecting the presence of specific chromosomal amplifications.
How it is Possible?
• Tumors are highly genetically unstable.
• Tumor related changes often are reflected at the chromosome level and are, by definition, specific to tumors.
• Genetic analyses can be done in very small tissues and are not subject to the method of detection.
Minimal Chromosome Probes That Can Detect Most Lung Cancers (n = 84)
ChromosomeAmplifications
# Detectable by Based on Any Alteration (n =84) Percentage
1q, 3q, 5p, 8q 83 98.8%
1q, 5q, 8q 80 95.2%
1q, 3q, 8q 78 92.3%
1q, 3q, 5p 77 91.7%
3q, 5p, 8q 75 89.3%
Method to Identify Genetic Changes in FNAs by FISH
Identify and prepare BAC probes unique to specific chromosomal regions
Protease digestion of biopsy samples and isolate nuclei
Hybridization with fluorescently labeled BAC probes
Visualize under fluorescent microscope for Ch. copy number changes
Correlate copy number changes with cytological/pathological findings and clinical outcome
Detecting Lung Cancer in FNA-obtained Spiral CT Identified Lung Lesions
• Probes Labeling: 1q and 5q (green)
8q and 3q (red)
nuclei (blue)
Samples: 20 paraffin embedded FNA samples 20 formalin fixed biopsies.
• All samples have pathology and clinical information.– 20 malignant– 10 benign specific– 10 benign non-specific
Sample 503 (Normal Lung)
Green: 5pRed: 8q
Normal samples often show 2 signals/cells representing their diploid status.
Sample 577 (Normal Lung)
Green: 5p, 2 signals/cellRed: 8q, 2 signals/cell
Cornell Sample: JJ001
Green: 1q, 5 signalsRed: 3q, 4 signals
Green: 5p, 9 signals
Sample: JJ003
Green: 1q, 6 signalsRed: 3q, 4 signals
A case is considered neoplastic or tumor when 5 or more signals were observed in a cell by one or more probes.
Sample: JJ005
Green: 1q, 8 signalsRed: 3q, 12 signals
Sample JJ006
Green: 1q, 4 signalsRed: 3q, 5 signals
Green: 5p, 4 signalsRed: 8q, 5 signals
Sample: JJ010
Red: 8q, 6 signalsGreen: 5p, 5 signals
Sample: JJ011
Green: 1q, 2 signalsRed: 3p, 6 signals
Sample: JJ012
Green: 1q, 2 signalsRed: 3p, 2 signals
Green: 5p, 2 signalsRed: 8q, 2 signals
Sample: JJ014
Green: 1q, >7 signalsRed: 3p, 2 signals
Sample: JJ017
Green: 5p, 10 signalsRed: 8q, 7 signals
Sample: JJ018
Green: 5p, 3 signalsRed: 8q, 6 signals
Green: 5p, 6 signalsRed: 8q, 9 signals