[Telomerase in lung cancer. Testing the activity of the "immortaligy enzyme" bronchial biopsies increases the diagnostic yield in cases of suspected peripheral bronchogenic carcinomas].
The proliferative capability is time-limited in normal somatic cells by the shortening of their chromosomal ends, the telomeres (Hayflick limit). An important feature of malignant cells is their immortality. The probably most common mechanism of tumour cells to achieve unlimited replicability is the activation of the enzyme telomerase. The reverse transcriptase can compensate the loss of telomeres. Using a PCR-based TRAP assay we found telomerase activity in tumour biopsies, exsudates and bronchial washings in various thoracic malignancies. In 38 of 47 patients with suspected peripheral lung cancer eventually surgery or invasive procedures proved a malignancy. In fluoroscopically guided bronchial brushings from 25 of these 38 patients (66%) the TRAP assay revealed telomerase activity. There was a single false positive case (tuberculosis) and with a single exception, the simultaneously taken brushes of the contralateral lobes were all telomerase negative. In 23 patients (61%) tumour cells were found in the cytological examination. In 33 patients at least one marker was positive. Thus the combination of cytology and telomerase test in bronchial brush biopsies attained a diagnostic yield of 87%.
Freitag
L
L
Lungenklinik Hemer Institut für experimentelle Pneumologie. lutzfrei@home.centernet.de
Litterst
P
P
Obertrifter
B
B
Velehorschi
V
V
Kemmer
H P
HP
Linder
A
A
Brightman
I
I
D001706:Biopsy / Q000379:methods; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry*; D002283:Carcinoma, Bronchogenic / Q000201:enzymology / Q000473:pathology* / Q000556:secondary / Q000601:surgery; D005189:False Positive Reactions; D006801:Humans; D008175:Lung Neoplasms / Q000201:enzymology / Q000473:pathology* / Q000601:surgery; D015203:Reproducibility of Results; D020133:Reverse Transcriptase Polymerase Chain Reaction; D019098:Telomerase / Q000032:analysis* / Q000235:genetics; D013899:Thoracic Neoplasms / Q000473:pathology* / Q000556:secondary / Q000601:surgery
D019098:Telomerase