TTF-1 + CK5

Product Description

Thyroid transcription factor-1 (TTF-1) is a member of the NKX2 family of homeodomain transcription factors. It is expressed in epithelial cells of the thyroid gland and lung. TTF-1 has been shown to be a sensitive (65-81%) and specific marker (94%) in the majority of primary lung adenocarcinomas. Studies have shown that TTF-1, used in combination with Napsin A, provided 93% sensitivity and 100% specificity for lung adenocarcinoma, if CK5 and Desmoglein 3 were both negative in the same case.

CK5 is a type II intermediate filament protein that is expressed in active basal layers of most stratified squamous epithelia. In a published study, rabbit monoclonal CK5 antibody was compared to mouse monoclonal CK5/6. CK5 was 84% sensitive and 100% specific for lung squamous cell carcinoma (SqCC) when compared to CK5/6 (80% sensitivity and 97% specificity). CK6 mRNA has been detected in lung adenocarcinomas; thus CK5 alone, may be a more specific marker than CK5/6. Studies have shown that CK5, used in combination with Desmoglein 3, provided 93.7% sensitivity with 100% specificity for lung SqCC.

TTF-1 (lung adenocarcinoma) is stained with DAB chromogen, and CK5 rabbit monoclonal (lung SqCC) is stained with a Fast Red chromogen. In most lung cancers tested, only a single antibody stain will be observed. Co-expressions of both antibodies may be an indication of adenosquamous cell carcinomas. When used in combination with Desmoglein 3 and Napsin A, a 93% staining sensitivity and 100% specificity was achieved for lung adenocarcinoma, and a 93.7% sensitivity and 100% specificity was achieved for lung SqCC; therefore, the antibody combination of TTF-1 + CK5 is a first class screener for discriminating between lung adenocarcinoma (TTF-1) vs. lung SqCC (CK5).

Specifications

Regulatory Notice: Biocare’s IVD-labeled products comply with US-FDA and European IVDD regulation. Other regions may have additional requirements for such labeling, please contact your local distributor.

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2. Tacha D, Yu C, Haas T. TTF-1, Napsin A, p63, TRIM29, Desmoglein-3 and CK5: An Evaluation of Sensitivity and Specificity and Correlation of Tumor Grade for Lung Squamous Cell Carcinoma vs. Lung Adenocarcinoma. Modern Pathology; Volume 24, Supplement 1, Feb 2011, Abstract 1808 page 425A.
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