Human telomerase is a ribonucleoprotein DNA polymerase which maintains the
telomeric region of human chromosomes and has been detected in all types of
human cancer tested. We used the telomeric repeat amplification protocol (
TRAP) assay to examine 71 non-small cell lung carcinomas (NSCLC) and their
adjacent normal tissue. Telomerase activity was detected in 61 (86%) of the
71 NSCLC examined but not in any of the matched normal lung tissues. A sig
nificant correlation was found between the presence of telomerase activity
and current smoking status at the time of diagnosis (p=0.0076). In addition
, a trend was found between telomerase activity and smoking exposure (p=0.0
6). Our findings demonstrate that telomerase activity is a common phenomeno
n in NSCLC cases but not in the normal lung. However, certain cases in form
er smokers may follow a telomerase independent pathway.