الفهرس 
Chapter 1: Lymphoproliferative disordersOnly 14 pages are availabe for public view
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Abstract
Genomic stability and integrity must be maintained for an organism to function and propagate successfully. Telomeres are one of several key elements required for genomic stability as they function to prevent chromosome fusions. Telomerase is the cellular ribonucleoprotein that is used by eukaryotic systems to counteract the ”end-replication problem”. Several telomerase related genes have been cloned and characterized, including those encoding the two major components of human telomerase: a RNA template, the human telomerase RNA component (hTR), and the human telomerase reverse transcriptase (hTERT). Introduction of the hTERT gene into human somatic cells produces telomerase activity and extends their replicative capacity. Whereas telomerase activity is detected in 85% of cancer cells, it is not or little in the majority of normal somatic tissues. High telomerase levels in most human cancers provide these cells unlimited replicative capacity and prevent lethal chromosomal instability. Regarding lymphoproliferative disorders, several studies on B-CLL demonstrated shortened telomeres and normal to relatively low levels of telomerase activity in early stage of CLL. Telomerase could be not only a powerful marker for cancer diagnosis and prognosis, but also a rational target for anticancer therapeutics. Specific inhibitors of telomerase should in theory target not only cancer cells but also germinal cells and certain stem cells. One concern for the application of such inhibitors is that these inhibitors will not be effective immediately, since cancer cells would continue dividing until their telomeres shorten enough to trigger senescence or apoptosis.