Telomerase is a ribonucleoprotein reverse transcriptase that synthesizes telomeric DNA onto chromosome ends, and is not detected in most normal cells. It has been clarified that some @entity957 may arise through the @entity4648 and @entity1141 sequence accompanied by accumulation of genetic mutations in metaplastic cells. Recently a highly sensitive polymerase chain reaction (PCR)-based telomerase assay (TRAP assay) was developed for the detection of telomerase activity. Telomerase activity has been found in most @entity5 , including @entity2 . The objective of this study was to determine whether telomerase RNA might increase in @entity1613 of the bronchi. Bronchial-brushing extracts were analyzed for telomerase activity (F-TRAP) and in situ telomerase activity using a fluorescence-based TRAP assay (in situ TRAP) and compared to cytological features. The fluorescence-based semi-quantitative TRAP assay detected telomerase activity in 8 out of 12 @entity2 cases (66.7%). In @entity957 , 6 out of 9 cases (66.7%) showed telomerase activity. On the other hand, in normal and @entity1613 of the bronchi, telomerase activity was not detected using either the F-TRAP method or in situ TRAP method. We concluded that @entity6349 cells might not contain immortalized cells, and that the increase of telomerase activity is a relatively late event during the bronchial @entity105 . It is difficult to distinguish between @entity1141 and in situ @entity189 of the bronchus morphologically, but the measurement of telomerase activity is clinically valuable for the determination of treatment.

Telomerase activity during XXXX in the bronchus.

@entity5 :: ('MESH:D009369', 'Disease') :: ['malignant neoplasms'] @entity957 :: ('MESH:D002294', 'Disease') :: ['squamous cell carcinoma', 'bronchial squamous cell carcinomas'] @entity2 :: ('MESH:D008175', 'Disease') :: ['lung cancer'] @entity189 :: ('MESH:D002277', 'Disease') :: ['carcinoma'] @entity4648 :: ('MESH:D008679', 'Disease') :: ['metaplasia'] @entity1613 :: ('MESH:D011230', 'Disease') :: ['precancerous lesions'] @entity105 :: ('MESH:D063646', 'Disease') :: ['carcinogenesis'] @entity6349 :: ('MESH:D004416', 'Disease') :: ['dysplastic'] @entity1141 :: ('MESH:C535662', 'Disease') :: ['dysplasia']
@entity105 :: (MESH:D063646,Disease) :: ['carcinogenesis']
