Telomere length, telomerase activity, and expressions of human telomerase mRNA component (hTERC) and human telomerase reverse transcriptase (hTERT) mRNA in pulmonary neuroendocrine tumors.
BACKGROUND
Telomeres are important for chromosome structure and function, protecting them against degradation. However, few studies have examined telomeres in pulmonary neuroendocrine (NE) tumors.


METHODS
We investigated deparaffinized sections obtained from 70 primary NE lung tumors [34 typical carcinoids (TCs), 10 atypical carcinoids (ACs), 16 large cell neuroendocrine carcinoma (LCNECs) and 10 small cell lung carcinomas (SCLCs)].


RESULTS
Positive expressions of human telomerase mRNA component (hTERC) and human telomerase reverse transcriptase (hTERT) mRNA were recognized, respectively, in 58% and 74% of TCs, and in 100% and 100% of ACs, LCNECs and SCLCs. Alteration of telomere length was greater in both LCNECs and SCLCs than in TCs. Telomerase activity was detected in LCNECs, but not in TCs. By the reverse-transcriptase polymerase chain reaction (RT-PCR), hTERC mRNA was detected in 100% of LCNECs and TCs examined, while hTERT mRNA was detected in 67% of LCNECs, but not at all in TCs.


CONCLUSIONS
These results suggest that alterations in telomere length, telomerase activity, and the expression of hTERT mRNA may (i) play roles in pathogenesis in pulmonary neuroendocrine tumors, and (ii) be a useful tool for differential diagnosis between TCs and LCNECs.
Nishio
Yuko
Y
Department of Pathology and Laboratory Medicine, National Defense Medical College, Tokorozawa, Saitama, Japan.
Nakanishi
Kuniaki
K
Ozeki
Yuichi
Y
Jiang
Shi-Xu
SX
Kameya
Toru
T
Hebisawa
Akira
A
Mukai
Makio
M
Travis
William D
WD
Franks
Teri J
TJ
Kawai
Toshiaki
T
D018278:Carcinoma, Neuroendocrine / Q000201:enzymology* / Q000235:genetics* / Q000473:pathology; D006801:Humans; D017403:In Situ Hybridization; D008175:Lung Neoplasms / Q000201:enzymology* / Q000235:genetics* / Q000473:pathology; D012313:RNA / Q000096:biosynthesis*; D012333:RNA, Messenger / Q000096:biosynthesis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D019098:Telomerase / Q000096:biosynthesis / Q000378:metabolism*; D016615:Telomere / Q000648:ultrastructure*
D012333:RNA, Messenger; C422952:telomerase RNA; D012313:RNA; C509186:TERT protein, human; D019098:Telomerase