Analysis of differentially expressed genes in neuroendocrine carcinomas of the lung.
BACKGROUND
Large cell neuroendocrine carcinoma (LCNEC) and small cell lung carcinoma (SCLC) show considerable differences in their histology but share neuroendocrine (NE) characteristics and also genetic and/or expression patterns.


METHODS
We used the subtractive expression method to identify differences in gene expression that would allow discrimination between these two types of NE lung carcinoma.


RESULTS
Eight cDNA fragments were transcribed at a higher level in LCNEC compared with SCLC, and these corresponded to five mitochondrial genes, two ribosomal genes, and one fetal regulation factor, neuronatin (NNAT). Immunohistochemically, NNAT protein was detected in 43% (6/14) of LCNECs but in only 8% (1/13) of SCLCs (p < 0.05). Positive staining for NNAT was observed in areas that did not show the NE morphology, such as palisading and rosettes.


CONCLUSIONS
The present results suggest that NNAT has the potential to be used as a differential maker between LCNEC and SCLC.
Okubo
Chigusa
C
Department of Pathology, Institute of Basic Medical Sciences, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Ibaraki, Japan.
Minami
Yuko
Y
Tanaka
Ryota
R
Uchihara
Teruhito
T
Anami
Yoichi
Y
Furuya
Shuichiroh
S
Morishita
Yukio
Y
Iijima
Tatsuo
T
Noguchi
Masayuki
M
D000818:Animals; D014408:Biomarkers, Tumor / Q000032:analysis; D019002:CD56 Antigen / Q000032:analysis; D018287:Carcinoma, Large Cell / Q000175:diagnosis / Q000235:genetics*; D018278:Carcinoma, Neuroendocrine / Q000175:diagnosis / Q000235:genetics*; D018288:Carcinoma, Small Cell / Q000175:diagnosis / Q000235:genetics*; D053379:Chromogranin A / Q000032:analysis; D003937:Diagnosis, Differential; D005260:Female; D020869:Gene Expression Profiling; D006801:Humans; D008175:Lung Neoplasms / Q000175:diagnosis / Q000235:genetics*; D008297:Male; D008565:Membrane Proteins / Q000032:analysis; D051379:Mice; D016513:Mice, SCID; D009419:Nerve Tissue Proteins / Q000032:analysis; D020411:Oligonucleotide Array Sequence Analysis; D012333:RNA, Messenger / Q000235:genetics; D016708:Synaptophysin / Q000032:analysis
D014408:Biomarkers, Tumor; D019002:CD56 Antigen; D053379:Chromogranin A; D008565:Membrane Proteins; C490237:NNAT protein, human; D009419:Nerve Tissue Proteins; D012333:RNA, Messenger; D016708:Synaptophysin