The alternative lengthening of telomeres pathway may operate in non-neoplastic human cells

    loading  Checking for direct PDF access through Ovid


The alternative lengthening of telomeres (ALT) mechanism represents an alternative to the enzyme telomerase in the maintenance of mammalian telomeres in 25–60% of sarcomas and a minority of carcinomas (about 5–15%). ALT-positive cells are distinguished by long and heterogeneous telomere length distributions by terminal restriction fragment (TRF) Southern blotting. Another diagnostic marker of ALT is discrete nuclear co-localized signals of telomeric DNA and the promyelocytic leukaemia protein (PML), referred to asALT-associatedPMLbodies (APBs). Recently, we detected smaller sized co-localized PML and telomere DNA (APB-like) bodies in endothelial cells adjacent to astrocytoma tumour cellsin situ. In this study, we examined a wide variety of non-neoplastic tissues, and report that co-localized signals of PML and telomere DNA are present in endothelial, stromal, and some epithelial cells. Co-localized signals of PML and telomere DNA showed an increased frequency in non-neoplastic cells with DNA damage. These results suggest that a mechanism similar to that in ALT-positive tumours also operates in non-neoplastic cells, which may be activated by DNA damage. Copyright © 2012 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

    loading  Loading Related Articles