Immunohistochemical staining with deltaNp63 is useful for distinguishing the squamous cell component of adenosquamous cell carcinoma of the lung.
BACKGROUND
DeltaNp63 is an isoform of the p53 homolog p63, which lacks an amino-terminal transactivation domain. The aim of this study was to detect the deltaNp63 expression in the squamous carcinoma component of adenosquamous carcinoma and evaluate its usefulness as a specific squamous carcinoma marker.


METHODS
Immunohistochemistry was used to analyze the protein expression of deltaNp63 and high molecular weight cytokeratin in paraffin-embedded tumor samples from 17 patients with well-characterized adenosquamous carcinoma.


RESULTS
Of 17 cases, 13 (76.5%) and 14 (82.4%) cases showed positive staining for deltaNp63 and HMWCK in the tumor cells, respectively. It was easy to discriminate the squamous carcinoma and adenocarcinoma components in all tumors. Interestingly, positive expression of deltaNp63 was detected in one case with a negative expression of HMWCK.


CONCLUSIONS
These findings indicated that the deltaNp63 status was useful for distinguishing squamous carcinoma from adenocarcinoma in formalin-postfixed adenosquamous carcinoma specimens.
Second Department of Surgery, School of Medicine, University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahatanishi-ku, Kitakyushu 807-8555, Japan. hidetaka@med.uoeh-u.ac.jp
Hidetaka
H
Uramoto
Sohsuke
S
Yamada
Takeshi
T
Hanagiri
D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000378:metabolism*; D018196:Carcinoma, Adenosquamous / Q000175:diagnosis / Q000378:metabolism*; D002289:Carcinoma, Non-Small-Cell Lung / Q000175:diagnosis / Q000378:metabolism*; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis / Q000378:metabolism*; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D007633:Keratins / Q000378:metabolism; D008175:Lung Neoplasms / Q000175:diagnosis / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D012189:Retrospective Studies; D015996:Survival Rate; D015534:Trans-Activators / Q000378:metabolism*; D014157:Transcription Factors; D016896:Treatment Outcome; D025521:Tumor Suppressor Proteins / Q000378:metabolism*
D014408:Biomarkers, Tumor; C115051:TP63 protein, human; D015534:Trans-Activators; D014157:Transcription Factors; D025521:Tumor Suppressor Proteins; D007633:Keratins