Objectives: To analyse the length of telomere restriction fragments (TRF) in different type of human astrocytomas as well as normal brain tissues and to evaluate the correlation of telomere status and tumor progression.
Methods: DNAs extracted from normal and tumor samples were studied with Southern blot analysis, using (TTAGGG)4 probe specific for human telomeric sequences.
Results: The lower portion of TRFs of astrocytoma type I, II and III was shortened gradually in comparison with that of normal brain tissues: both uper and lower portions of TRFs in 12 cases of glioblastoma multiformes studied were lost distinctively. However, no obvious length difference of TRFs could be detected between primary and recurrent glioblastomas.
Conclusions: Telomere reduction is one of the important genetic events during transformation of astrocytomas. Telomere repair mechanism may be initiated in glioblastoma cells which may, therefore, maintain a relative stabitity of TRFs and permit a constitutive proliferation of those malignant cells.