E. Hiyama et al., TELOMERASE ACTIVITY IN NEUROBLASTOMA - IS IT A PROGNOSTIC INDICATOR OF CLINICAL BEHAVIOR, European journal of cancer, 33(12), 1997, pp. 1932-1936
Neuroblastomas show remarkable biological heterogeneity, resulting in
favourable prognosis or unfavourable prognosis due to aggressive growt
h despite multimodal therapy. Recently, we proposed that aggressive tu
mours express telomerase at a high level while the favourable tumours
lack or have low telomerase expression. To evaluate the correlation be
tween telomerase activity and other biological characteristics reporte
d as prognostic markers (MYCN gene amplification, loss of heterogeneit
y (LOH) in the short arm of chromosome 1, trk-A expression, Ha-ras p21
expression, and DNA ploidy), we investigated these biological feature
s in 105 untreated neuroblastomas. In these cases, 23 showed high telo
merase activity, 78 showed low activity, and telomerase activity was u
ndetectable in 4 cases. Most tumours with genetic alterations (MYCN am
plification or 1p32 LOH) showed high telomerase activity. Most tumours
with low or undetectable activity were aneuploid, and showed trk-A an
d Ha-ras expression. Three of the four tumours with undetectable telom
erase activity regressed. In 2 of the tumours with low telomerase acti
vity, the residual tumours maturated and showed repression of telomera
se activity. Thus, the level of telomerase activity correlated with ot
her genetic alterations and/or gene expression and may be a useful pro
gnostic indicator in neuroblastoma. (C) 1997 Elsevier Science Ltd.