[Azidothymidine, blocking telomerase functioning, shortens telomeric repeats in transformed human cells]

The long-term action of azidothymidine, reverse transcriptase inhibitor, on cultivated U-937 (human promyelocyte leukemia) and MeWo (human melanoma) cells led to the concentration-dependent decrease in the length of telomeric chromosomal repeats. Telomere shortening was accompanied by temporary retardation of cell proliferation. Combined with the data obtained previously, these results suggest that azidothymidine inhibits telomerase functioning in cultivated cells.