Significant expression of thyroid transcription factor-1 in pulmonary squamous cell carcinoma detected by SPT24 monoclonal antibody and CSA-II system.

Abstract

In contrast to the usefulness of thyroid transcription factor-1 (TTF-1) in distinguishing primary adenocarcinoma of the lung from metastatic lesions, TTF-1 expression in pulmonary squamous cell carcinoma is reported to be at low level and not a suitable immunohistochemical marker. We hypothesized that the highly sensitive detection system, CSA-II, can visualize even faint expression of TTF-1 in pulmonary squamous cell carcinoma. In this study, 2 commercially available clones of TTF-1 monoclonal antibody, 8G7G3/1 and SPT24, were used for staining 38 cases of pulmonary squamous cell carcinoma, in combination with the CSA-II and the conventional detection system, EnVision. The combined use of the 8G7G3/1 clone with EnVision and CSA-II showed a positive reaction in only 1 and 4 cases, respectively. The use of SPT24 clone showed positive staining in 5 cases with EnVision and in 20 of 38 cases (52.6%) with the CSA-II. Interestingly, positive staining by the SPT24-CSA-II technique of samples from tissue blocks preserved for <2 years was 73.6% compared with only 31.5% in those preserved for >2 years. In addition, a 6-month preservation of the cut sections resulted in stain fading and decreased positivity (50%), compared with freshly cut sections. We conclude that the use of the SPT24 monoclonal antibody with the CSA-II system can detect even weak expression of TTF-1 in pulmonary squamous cell carcinoma. This staining technique can potentially allow the discrimination of primary squamous cell carcinoma of the lung from metastatic lesions, especially in freshly prepared paraffin sections.

• Authors: Kenji Kashima, Hisashi Hashimoto, Haruto Nishida, Motoki Arakane, Naomi Yada, Tsutomu Daa, Shigeo Yokoyama
• Journal: Applied immunohistochemistry & molecular morphology : AIMM (Appl Immunohistochem Mol Morphol) Vol. 22 Issue 2 Pg. 119-24 ( 2014) ISSN: 1533-4058 [Electronic] United States
• PMID: 23531851 (Publication Type: Evaluation Study, Journal Article)

Chemical References

• Antibodies, Monoclonal
• Biomarkers, Tumor
• NKX2-1 protein, human
• Nuclear Proteins
• Reagent Kits, Diagnostic
• Thyroid Nuclear Factor 1
• Transcription Factors

Topics

• Antibodies, Monoclonal (metabolism)
• Biomarkers, Tumor (immunology, metabolism)
• Carcinoma, Squamous Cell (diagnosis, immunology)
• Diagnosis, Differential
• Humans
• Immunohistochemistry (methods)
• Lung Neoplasms (diagnosis, immunology)
• Neoplasm Metastasis
• Nuclear Proteins (immunology, metabolism)
• Reagent Kits, Diagnostic
• Thyroid Nuclear Factor 1
• Transcription Factors (immunology, metabolism)