Telomere length, telomerase activity, and expressions of human telomerase mRNA component (hTERC) and human telomerase reverse transcriptase (hTERT) mRNA in pulmonary neuroendocrine tumors

Jpn J Clin Oncol. 2007 Jan;37(1):16-22. doi: 10.1093/jjco/hyl118. Epub 2006 Oct 23.


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.

MeSH terms

  • Carcinoma, Neuroendocrine / enzymology*
  • Carcinoma, Neuroendocrine / genetics*
  • Carcinoma, Neuroendocrine / pathology
  • Humans
  • In Situ Hybridization
  • Lung Neoplasms / enzymology*
  • Lung Neoplasms / genetics*
  • Lung Neoplasms / pathology
  • RNA / biosynthesis*
  • RNA, Messenger / biosynthesis
  • Reverse Transcriptase Polymerase Chain Reaction
  • Telomerase / biosynthesis
  • Telomerase / metabolism*
  • Telomere / ultrastructure*


  • RNA, Messenger
  • telomerase RNA
  • RNA
  • TERT protein, human
  • Telomerase